WO2011052790A1 - Luminescent pointing device and electronic device comprising same - Google Patents

Abstract

Disclosed is a luminescent pointing device (30) that employs a light-guiding optical member, wherein the impact of stray light on image data captured by an image capture element is alleviated. The luminescent pointing device (30), which uses a cover part (24) as the light-guiding optical member, comprises a stray light preventing prism (19A), upon the rear surface of the cover part (24), which changes the path of light that is emitted by a light source (16), and that is incident to the image capture element (15) without traversing an image forming element (14).

Description

Optical pointing device and electronic device including the same

The present invention relates to an optical pointing device and an electronic device including the same, and more specifically, an optical pointing device as an input device that can be mounted on a portable information terminal (electronic device) such as a mobile phone or a PDA (Personal Digital Assistants). It relates to the device.

In a small electronic device represented by a portable information terminal such as a mobile phone or a PDA, a keypad is generally adopted as a user interface for inputting information. The keypad is usually composed of a plurality of buttons for inputting numbers and characters and direction buttons (cross keys). In recent years, with the display of graphics and the like being possible on the display unit of portable information terminals, a GUI (Graphical User Interface) that uses the display unit in two dimensions is mainly used as a method for displaying information to the user. It is becoming.

As described above, since the portable information terminal is highly functional and has a display function equivalent to that of a computer, the input means of the conventional portable information terminal that uses menu keys and other function keys as direction keys are expressed in GUI. It is not suitable for selecting an icon or the like and is inconvenient. For this reason, a portable information terminal is required to have a pointing device that enables intuitive operation, such as a mouse such as a ball mouse or an optical mouse used in a computer, a touch pad, or a tablet. ing.

However, since the portable information terminal is assumed to be carried, there is a problem in adopting a separate pointing device separated from the main body as the pointing device of the portable information terminal. In addition, since a track ball type (Track Ball-Type) pointing device physically occupies a certain three-dimensional space, there is a problem that it is difficult to adopt for a thin and small portable information terminal.

Therefore, as a pointing device that can be mounted on a portable information terminal, a subject (for example, a fingertip) that contacts the pointing device is observed with an image sensor, and a change in the pattern of the subject (for example, a fingerprint) on the contact surface is extracted. Has proposed an optical pointing device that detects the movement of a subject. That is, an image of a subject formed by light reflected by the subject is continuously captured by an image sensor such as an image sensor, and a change amount of the captured image data with respect to the image data captured immediately before is extracted. There has been proposed an optical pointing device that calculates the movement of a subject based on the amount and outputs it as an electrical signal. By using this optical pointing device, the cursor or the like shown on the display can be moved in accordance with the movement of the subject.

For example, Patent Document 1 discloses a reflecting mirror that reflects light emitted from a light source and reflected by a subject in a horizontal direction (when the apparatus is placed horizontally), and vertically facing a horizontal ray path. An optical pointing device including an installed condensing lens and an image sensor (imaging device) is described (see abstract of Patent Document 1).

In the optical pointing device of Patent Document 1, light emitted from a light source is shielded by a block-shaped light shielding wall provided with a reflecting mirror so that it does not directly enter the image sensor. That is, in the optical pointing device of Patent Document 1 that guides light to the image sensor with a reflecting mirror, the light emitted from the light source becomes stray light (light that does not pass through a prescribed light path) without being reflected by the subject. Therefore, it is possible to easily prevent light from being received.

On the other hand, in recent years, with the miniaturization of devices found in mobile phones and the high integration found in devices having a plurality of functions, there has been a demand for smaller and thinner input devices. Therefore, an optical pointing device that has been reduced in size and thickness has been proposed (Patent Documents 2 and 3).

For example, in an ultra-thin optical joystick that is an optical pointing device disclosed in Patent Document 3, a subject on a contact surface is irradiated by a light source such as an LED, and light scattered from the subject is reflected by a condenser lens. Focus on the image sensor, continuously capture the subject image with an image sensor such as an image sensor, extract the amount of change in the captured image data from the image data captured immediately before, and move the subject based on the amount of change And the movement of the subject is output as an electrical signal. By using this optical pointing device, the cursor or the like shown on the display can be moved in accordance with the movement of the subject.

The optical system in the ultra-thin optical joystick 100α disclosed in the above-mentioned Patent Document 3 includes a light source unit 110α including an LED 111α and a reflection mirror 112α as shown in FIG. 25 in order to reduce the size and thickness of the device. A first waveguide 120α having a first reflecting surface 121α and a first plano-convex lens portion 122α, a second waveguide 130α having a second reflecting surface 131α and a second plano-convex lens portion 132α, and an image sensor 140α. A cover glass 102α with which a subject 101α such as a finger contacts, and a blocking unit 150α that blocks surrounding noise light provided in a space located between the first plano-convex lens unit 122α and the second plano-convex lens unit 132α It is made up of.

In the ultra-thin optical joystick disclosed in Patent Document 3, since the first waveguide 120α and the second waveguide 130α include the reflection surface and the lens portion, the height of the optical joystick is about 2 mm or less. Can be reduced to. For this reason, an ultra-thin optical joystick is provided.

Also in Patent Document 4, as in Patent Document 3, a bending optical element such as a prism is disposed immediately below the contact surface, and an optical pointing device that forms an image on an imaging element by bending reflected light from a subject in a horizontal direction. An optical joystick has been proposed. Thereby, it is possible to realize an optical pointing device having a short length in the vertical direction while taking a long optical path, thereby realizing a reduction in thickness of the optical pointing device.

As this type of optical pointing device, for example, Patent Document 4 discloses a reflecting mirror that reflects light emitted from a light source and reflected by a subject in a horizontal direction (when the device is placed horizontally), and a horizontal mirror. An optical joystick having a condensing lens and an image sensor (imaging device) that are vertically disposed opposite to each other on the light path is disclosed. Thereby, it is possible to realize an optical pointing device having a short length in the vertical direction while taking a long optical path, thereby realizing a reduction in thickness of the optical pointing device.

Japanese Patent Gazette “Special Table 2008-507787 (published March 13, 2008)” Japanese Patent Publication “Japanese Patent Laid-Open No. 2008-226224 (published on September 25, 2008)” Japanese Patent Gazette “Special Table 2008-510248 Publication (April 3, 2008)” Japanese Patent Publication “JP 2009-176271 A (published on August 6, 2009)”

However, the optical pointing device described in Patent Documents 2 to 3 is reduced in size and thickness so that the optical system and the like are reduced and the capacity is reduced. Since no light shielding wall or the like can be provided, stray light cannot be shielded. When stray light is received by the image sensor, the light (scattered light) reflected by the subject cannot be sufficiently recognized by the effect of stray light when the image sensor receives light reflected from the subject. The performance of the pointing device is reduced. Therefore, a countermeasure for preventing stray light from being received by the image sensor is demanded.

By the way, in an optical pointing device that uses a light source, a waveguide, and the like to emit light from the light source, bend the reflected light from the subject in the horizontal direction, and form an image on the image sensor through the waveguide. It is necessary to prevent stray light from a light source or the like from entering the image sensor.

In this regard, in the optical joystick 200α disclosed in Patent Document 4, as shown in FIG. 26, the light from the light source 205α is collected by the prism 201α and the collecting light in the cover member 204α constituting the prisms 201α and 202α and the condenser lens 203α. The stray light that diffuses upward when passing through the optical lens 203α and the prism 202α is shielded by the sheet-like miscellaneous light shielding wall 211α provided on the upper side of the cover member 204α, and the stray light that diffuses downward is covered by the cover member 204α. It is shielded by a sheet-like miscellaneous light shielding wall 212α provided on the side.

However, in a conventional optical pointing device, when a light guide type optical member in which optical elements such as a prism and a condenser lens are integrated as an optical member and the inside of the member is guided by reflection is used, Reflected light that becomes stray light or direct light from the light source is not emitted to the outside of the light guide type optical member. Therefore, even if the upper surface or the lower surface of the light guide type optical member is shielded by a wall, there is no use. As a result, there is a problem that stray light cannot be prevented from entering the image sensor.

By the way, in an optical pointing device that emits light from a light source and bends reflected light from a subject in the horizontal direction to form an image on an image sensor, stray light from a light source or the like is prevented from entering the image sensor. There is a need.

In this regard, in the optical joystick 100β disclosed in Patent Document 4, as shown in FIG. 39, in the optical member 104β constituting the prisms 101β and 102β and the condensing lens 103β, the light from the light source 105β is collected into the prism 101β. When passing through the optical lens 103β and the prism 102β, the stray light diffused laterally is blocked by the block-shaped holder 107β. Further, the stray light diffusing upward is shielded by the sheet-like miscellaneous light shielding wall 111β provided on the upper side of the optical member 104β, and the stray light diffusing downward is provided on the lower side of the optical member 104β. It is shielded by the shielding wall 112β.

However, in the conventional optical pointing device, providing a shielding wall as disclosed in Patent Document 4 is an obstacle to further reducing the thickness and size. As a result, there is a problem that stray light cannot be prevented from entering the image sensor.

When stray light is received by the image sensor, when the image sensor receives light reflected from the subject (scattered light), the light (scattered light) cannot be sufficiently recognized due to the influence of stray light, The performance of the optical pointing device is degraded. Therefore, a countermeasure for preventing stray light from being received by the image sensor is demanded.

The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide an optical pointing device in which the influence of stray light on image data captured by an image sensor is reduced even in a thin optical pointing device, And providing an electronic apparatus including the same.

A further object of the present invention is to provide stray light easily when using a light guide type optical member that is integrally formed including an optical path changing means and an imaging reflection portion and guides the inside by reflection. It is an object of the present invention to provide an optical pointing device with high detection accuracy of an object and an electronic apparatus including the same.

Another object of the present invention is to provide an optical pointing device capable of reducing the influence of stray light on image data captured by an image sensor without providing a new shielding wall, and an electronic apparatus including the same. is there.

In order to solve the above problems, an optical pointing device of the present invention includes a light source that irradiates light to a subject, a light guide type optical member that reflects reflected light from the subject and guides the inside, and the light guide. An optical pointing device including an imaging element that receives light guided by the optical optical member, wherein the optical guiding member includes an imaging reflection unit that guides the guided light to the imaging element. And stray light that changes the path of light that is emitted from the light source and is incident on the image sensor without passing through the imaging reflector on the back surface of the light guide optical member on which the light source and the image sensor are provided. It is characterized by having a prevention part.

According to the above configuration, the light guide type optical member is provided with a countermeasure (stray light countermeasure) against light that is directly incident on the image sensor without reflection of light emitted from the light source by the subject. That is, a stray light prevention unit that prevents light emitted from the light source from entering the imaging element without being reflected by the subject is formed on the back surface of the light guide type optical member. Accordingly, when light that has not been reflected by the subject that causes stray light among the light emitted from the light source reaches the stray light prevention unit, the path changes when the light is emitted from the stray light prevention unit. Therefore, the light emitted from the light source can be prevented from becoming stray light without being reflected by the subject.

Further, according to the above configuration, since the stray light preventing portion is formed on the back surface of the light guide type optical member, stray light can be prevented even in a thin optical pointing device.

Therefore, even in a thin optical pointing device, it is possible to provide an optical pointing device that can reduce the influence of stray light on the image data captured by the imaging device.

Note that the stray light prevention unit is preferably provided so as to avoid the path of the signal light for detecting the subject. Thereby, it is possible to prevent stray light from entering the imaging element without reducing the detection sensitivity of the signal light.

In order to solve the above problems, an optical pointing device of the present invention includes a light source that irradiates light to a subject, a light guide type optical member that reflects and guides reflected light from the subject, and An optical pointing device including an imaging device that receives light guided by a light guide type optical member, wherein the light guide type optical member has a contact surface that contacts the subject and light that is guided An imaging reflection part that guides the image to the imaging element and an optical path changing unit that changes the direction of the reflected light from the subject and guides it to the imaging reflection part. The optical type optical member is disposed on the lower side of the light source side than the imaging reflection portion, and the light guide type optical member is further coupled with reflected light from the subject or direct light from the light source. Directly incident on the image sensor without going through the image reflector Is characterized in that notches for preventing Rukoto is formed on at least part of the light source side of the straight upper surface of the image sensor.

According to the above invention, the optical pointing device includes a light source that irradiates light to a subject, a light guide type optical member that reflects and reflects light reflected from the subject inside, and the light guide type optical member. An image sensor that receives the guided light. The light guide type optical member includes a contact surface that contacts the subject, an imaging reflection unit that guides the guided light to the image sensor, and a direction of reflected light from the subject to change the connection. Optical path conversion means for guiding to the image reflecting portion is integrally formed. Therefore, by adopting such a light guide type optical member, even if the optical path length of the optical system is increased and aberrations are suppressed, the length of the light guide type optical member in the vertical direction is compared with the optical path length. Therefore, the size can be reduced. In addition, the number of components can be reduced by integrally forming the contact surface, the optical path changing means, and the imaging reflection part.

However, in the light guide type optical member in which the contact surface, the optical path changing means and the imaging reflection part are integrally formed, stray light such as reflected light from the subject or direct light from the light source does not pass through the imaging reflection part. The stray light may be directly incident on the image sensor, and such stray light is transmitted from the contact surface to the image sensor through the optical path conversion unit and the imaging reflection unit. It is a scattered light component from the incident subject, and Noise is an unnecessary light component that enters the image sensor through the other optical path).

Therefore, in the present invention, the light guide type optical member has a cutout portion for preventing the reflected light from the subject or the direct light from the light source from directly entering the imaging element without passing through the imaging reflection portion. It is formed on at least part of the light source side on the top surface of the image sensor. For this reason, by forming a notch on at least a part on the light source side on the top surface of the image sensor, stray light composed of reflected light from the subject or direct light from the light source that does not pass through the imaging reflection unit, When the light is emitted from the inside of the light guide type optical member, it is reflected by the notch, the incident angle changes, and it can be prevented from being emitted from the inside of the light guide type optical member. As a result, it is possible to prevent stray light, which is reflected light from the subject not passing through the imaging reflection unit or direct light from the light source, from directly entering the image sensor.

Further, in the present invention, in order to prevent stray light, only a notch portion is formed in the light guide type optical member. Therefore, it is possible to suppress stray light incident on the image sensor with a simple configuration without using a special light shielding wall or light shielding member.

Therefore, when using a light guide type optical member in which an optical path changing unit and an imaging reflection unit are integrated, it is possible to easily reduce the influence of stray light and provide an optical pointing device with high object detection accuracy. it can.

In order to solve the above problems, the optical pointing device of the present invention includes a light source that irradiates light on a contact surface of a subject, and an imaging element that forms an image of scattered light from the subject on an imaging device. In the optical pointing device, in the outer peripheral area of the imaging element and within the range where the direct light from the light source, scattered light from the subject or other disturbance light reaches, the light reflected by the outer peripheral area or the outer peripheral area A structure is provided in which an optical path of light transmitted through the light source is changed to prevent the light from entering the imaging element as noise light.

According to the above invention, the optical pointing device includes the light source that irradiates light on the contact surface of the subject and the imaging element that forms an image of the scattered light from the subject on the imaging element. Therefore, by adopting such an optical pointing device, the optical path length of the optical system can be made longer, the length in the vertical direction can be made smaller than the optical path length, and miniaturization can be achieved.

However, in such an optical pointing device, direct light from the light source, scattered light from the subject, or other disturbance light may be directly incident on the image sensor without passing through the imaging element. Etc. reduce the S / N (Signal / Noise) of the image sensor.

On the other hand, in the present invention, in the outer peripheral region of the imaging element and within the range where direct light from the light source, scattered light from the subject, or other disturbance light reaches, the light reflected by the outer peripheral region or There is provided a structure that changes the optical path of the light transmitted through the outer peripheral region and prevents the light from entering the imaging element as noise light. This structure is made of a scattering surface such as a prism.

For this reason, light or the like from the light source that is not reflected by the subject that causes stray light or the like is reflected by the structure in a specific direction and is prevented from entering the imaging element as noise light. As a result, it is possible to prevent the light emitted from the light source from becoming stray light without being reflected by the subject.

Further, the structure is not a new shielding wall because it suppresses incident light as noise light to the imaging element by changing the optical path of light reflected by the outer peripheral region or transmitted through the outer peripheral region.

Therefore, it is possible to provide an optical pointing device that can reduce the influence of stray light on the image data captured by the image sensor without providing a new shielding wall.

As described above, in the optical pointing device and the electronic apparatus according to the present invention, the light guide type optical member includes a contact surface that contacts the subject and a light guide light that is guided to the imaging reflection unit to the imaging element. The light guide in which the image reflection unit and the optical path conversion unit that converts the direction of the reflected light from the subject and guides it to the imaging reflection unit are formed integrally, and further, the light source and the image sensor are provided. The back surface of the mold optical member is provided with a stray light prevention unit that changes the path of light that is emitted from the light source and enters the image sensor without passing through the imaging reflection unit. Therefore, even in a thin optical pointing device, it is possible to provide an optical pointing device and an electronic device that can reduce the influence of stray light on image data captured by the image sensor.

In the optical pointing device of the present invention, as described above, the light guide type optical member includes a contact surface with which the subject comes in contact, an imaging reflection unit that guides the guided light to the imaging device, and the subject. And an optical path changing unit that changes the direction of the reflected light and guides the reflected light to the imaging reflection unit, and the imaging element is closer to the light source than the imaging reflection unit in the light guide type optical member. In addition to being disposed on the lower side, reflected light from the subject or direct light from the light source is directly incident on the imaging element without passing through the imaging reflection unit. A notch for preventing the light is formed on at least a part of the light source side on the top surface of the image sensor.

Further, as described above, the electronic apparatus of the present invention includes the optical pointing device described above.

Therefore, in the case of using a light guide type optical member in which the optical path conversion means and the imaging reflection unit are integrated, the influence of stray light is easily reduced, and an optical pointing device with high object detection accuracy and the same are provided. This provides the effect of providing electronic equipment.

In addition, as described above, the optical pointing device of the present invention is an outer peripheral region of the imaging element, in a range where direct light from the light source, scattered light from the subject, or other disturbance light reaches. The structure which suppresses entering into the said image pick-up element as noise light by changing the optical path of the light reflected in (4) or the light which permeate | transmitted this outer peripheral area | region is provided.

Further, as described above, the electronic apparatus of the present invention includes the optical pointing device described above.

Therefore, it is possible to provide an optical pointing device that can reduce the influence of stray light on the image data captured by the image sensor without providing a new shielding wall, and an electronic device including the same.

It is sectional drawing which shows schematic structure of the optical pointing device in the 1st Embodiment of this invention. It is a perspective view which shows the structure of the back surface of the cover part in the optical pointing device of FIG. It is a figure which compares the stray light prevention effect of an optical pointing device, (a) is sectional drawing of the optical pointing device which does not have a stray light prevention structure, (b) is sectional drawing of the optical pointing device which has a stray light prevention structure is there. It is a figure which shows the transmittance | permeability and the reflectance with respect to the wavelength of the light in the reflecting film with which the optical pointing device of FIG. 1 is provided. It is a perspective view explaining the assembly method of the optical pointing device of FIG. It is sectional drawing which shows schematic structure of the optical pointing device in the 2nd Embodiment of this invention. It is a figure which shows the shape of the diffraction element and the groove pattern of a diffraction element in the optical pointing device of FIG. It is a figure which shows the shape of the diffraction element in the optical pointing device of FIG. It is sectional drawing which shows schematic structure of the optical pointing device in the 3rd Embodiment of this invention. It is a figure which shows the electronic device in the 4th Embodiment of this invention, and is a schematic diagram which shows the external appearance of the mobile telephone carrying the optical pointing device of this invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates an embodiment of an optical pointing device according to the present invention, and is a cross-sectional view illustrating a configuration of an optical pointing device. It is a perspective view which shows the structure of the cover part of the said optical pointing device. (A) is a top view which shows the structure of the cover part of the said optical pointing device, (b) is sectional drawing which shows the structure of the cover part of the said optical pointing device. It is sectional drawing which shows the optical path until the irradiation light with the spreading | diffusion irradiated from the light source in the said optical pointing device is reflected by a to-be-photographed object, and injects into an image pick-up element. (A) (b) is sectional drawing which shows the optical path in case the stray light from the to-be-photographed object in the said optical pointing device is directly input into an image pick-up element. It is sectional drawing which shows the optical path in case the stray light from the light source in the said optical pointing device is directly input into an image pick-up element. It is sectional drawing which shows the condition where the stray light from the light source in the said optical pointing device changes an optical path just before an image pick-up element by a notch part. It is sectional drawing which shows the cover part which formed the light shielding film in the said notch part. (A) is a distribution diagram showing the illuminance distribution in the image sensor when the cover portion has no notch, and (b) is a distribution showing the illuminance distribution in the image sensor when only the notch portion is present in the cover portion. (C) is a distribution diagram showing the illuminance distribution in the image pickup device when a notch is formed in the cover and a light shielding film is applied, and (d) is a distribution diagram (a) and (b). , (C) is a graph collectively shown as one. FIG. 5 is a cross-sectional view showing another embodiment of the optical pointing device according to the present invention and showing the configuration of the optical pointing device. (A) is a cross-sectional view showing the shape of a reflective diffraction element as a diffraction element provided in the optical pointing device, and (b) to (e) are plan views showing groove patterns of the diffraction element. It is sectional drawing which shows the shape of a reflection type Fresnel lens as said diffraction element. FIG. 14 is a cross-sectional view showing still another embodiment of the optical pointing device according to the present invention and showing the configuration of the optical pointing device. (A) shows one Embodiment of the electronic device provided with the optical pointing device in this invention, and is a front view which shows the external appearance of the mobile telephone as an electronic device carrying an optical pointing device, (b) Is a rear view, and (c) is a side view. It is sectional drawing which shows the structure of the conventional optical pointing device. It is an assembly disassembled perspective view which shows the structure of the other conventional optical pointing device. (A) shows one Embodiment of the optical pointing device in this invention, Comprising: It is sectional drawing which shows the structure of an optical pointing device, (b) is a perspective view which shows the structure of the cover part of the said optical pointing device. FIG. It is a bottom view which shows the optical path from a light source when a structure does not exist in the outer periphery of the image formation element in the said optical pointing device. It is a bottom view which shows the optical path from a light source in case the structure exists in the outer periphery of the image formation element in the said optical pointing device. (A) is a plan view showing a configuration of another structure in the optical pointing device, and (b) is a cross-sectional view taken along line A-A ′ of (a). (A) is a plan view showing a configuration of still another structure in the optical pointing device, and (b) is a cross-sectional view taken along line B-B ′ of (a). (A) is a plan view showing a configuration of still another structure in the optical pointing device, and (b) is a cross-sectional view taken along the line C-C ′ of (a). It is a bottom view which shows the optical path from a light source in case the structure does not exist in the side surface side flange of the cover part in the said optical pointing device. It is a bottom view which shows the optical path from a light source in case the structure exists in the side surface side flange of the cover part in the said optical pointing device. It is a bottom view which shows the optical path from a light source in case the structure exists in the front-and-rear side flange of the cover part in the said optical pointing device. FIG. 5 is a cross-sectional view showing another embodiment of the optical pointing device according to the present invention, showing the configuration of the optical pointing device including a lens and the optical path from the light source. It is a top view which shows the structure of the optical pointing device provided with the said lens, and the optical path from a light source. (A) shows one Embodiment of the electronic device provided with the optical pointing device in this invention, Comprising: It is a front view which shows the external appearance of the mobile telephone as an electronic device carrying an optical pointing device, (b) ) Is a rear view thereof, and (c) is a side view thereof. It is an assembly exploded perspective view which shows the structure of the conventional optical pointing device.

Each embodiment of the present invention will be described by taking an optical pointing device using an LED as a light source module as an example. The optical pointing device of the present invention detects the movement of a subject by irradiating a subject such as a fingertip with light and receiving light reflected from the subject. Hereinafter, the configuration of the optical pointing device of each embodiment will be specifically described. Moreover, about the member which shows the same function and effect | action, the same code | symbol is attached | subjected and description is abbreviate | omitted.

[First Embodiment]
A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic sectional view of an optical pointing device 30 according to the first embodiment. As shown in FIG. 1, the optical pointing device 30 includes a substrate portion 26 and a cover portion (light guide type optical member) 24. The substrate unit 26 includes a circuit board 21, a light source 16, an image sensor 15, and a transparent resin 20. The cover unit 24 includes a contact surface 11, a bending element 12 (an optical path conversion unit, a prism) that forms the inclined surface 13, an imaging element (imaging reflection unit) 14, and reflection surfaces 17 and 18 (an optical path conversion unit). The subject 10 in contact with the contact surface 11 of the cover unit 24 is a subject such as a fingertip, and is an object for which the optical pointing device 30 detects the movement of the fingerprint of the finger. Here, in order to make it easy to understand the state of the subject 10 with respect to the optical pointing device 30, the subject 10 is described as being small relative to the optical pointing device 30.

Here, the thickness direction (vertical direction in FIG. 1) of the optical pointing device 30 is defined as the Z axis, and the width direction (horizontal direction in FIG. 1) of the optical pointing device 30 is defined as the Y axis. The direction from the lower part to the upper part of the optical pointing device 30 is the positive direction of the Z axis, and the direction from the light source 16 to the image sensor 15 is the positive direction of the Y axis. The positive direction of the Z axis is also called the vertical direction, and the positive direction of the Y axis is also called the horizontal direction. Although not shown, the depth direction of the optical pointing device 30 is the X axis, and the direction from the back side to the near side of the optical pointing device 30 shown in FIG. 1 is the positive direction of the X axis.

First, the configuration of the substrate unit 26 will be described. In the present embodiment, the light source 16 and the image sensor 15 are mounted on one circuit board 21. The light source 16 and the image sensor 15 are electrically connected to the circuit board 21 by wire bonding or flip chip mounting. A circuit is formed on the circuit board 21. The circuit controls the light emission timing of the light source 16 or receives an electrical signal output from the image sensor 15 to detect the movement of the subject. The circuit board 21 has a planar shape made of the same material, and is made of, for example, a printed board or a lead frame.

The light source 16 emits light toward the contact surface 11 of the cover portion 24. The light M emitted from the light source 16 is refracted by the bending element 12 of the cover portion 24 through the transparent resin 20, the traveling direction is changed, and reaches the contact surface 11. That is, the light M enters the contact surface from an oblique direction (at a certain incident angle with respect to the contact surface). As will be described later, since the cover portion 24 is made of a material having a refractive index larger than that of air, the light M that has reached the contact surface 11 partly touches the contact surface 11 when the subject 10 does not exist on the contact surface 11. The light is transmitted and the remaining part is reflected by the contact surface 11. At this time, when the incident angle of the light M with respect to the contact surface 11 satisfies the condition of total reflection, the light M does not pass through the contact surface 11 but is reflected by the contact surface 11 and travels into the cover portion 24. On the other hand, when the subject 10 is on the contact surface 11, the light M is reflected by the surface of the subject 10 in contact with the contact surface 11 and is incident on the cover unit 24. The light source 16 is realized by a light source such as an LED, for example, and is preferably realized by an infrared light emitting diode with high brightness.

The image sensor 15 receives the light L reflected from the subject 10 irradiated by the light source 16, forms an image on the contact surface 11 based on the received light, and converts the image into image data. Specifically, the image sensor 15 is an image sensor such as a CMOS or a CCD. The image sensor 15 includes a DSP (Digital Signal Processor: calculation unit) (not shown), and captures received light as image data in the DSP. The image sensor 15 continues to capture images on the contact surface 11 at regular intervals in accordance with instructions from the circuit board 21.

When the subject 10 in contact with the contact surface 11 moves, the image captured by the image sensor 15 is different from the image captured immediately before. In the DSP, the image sensor 15 compares the values of the same portion of the captured image data with the immediately preceding image data, and calculates the movement amount and movement direction of the subject 10. That is, when the subject 10 on the contact surface 11 moves, the captured image data is image data indicating a value deviated from the image data captured immediately before by a predetermined amount. In the DSP, the image sensor 15 calculates the movement amount and movement direction of the subject 10 based on the predetermined amount. The image sensor 15 outputs the calculated movement amount and movement direction to the circuit board 21 as electric signals. The DSP may be included in the circuit board 21 instead of in the image sensor 15. In that case, the image sensor 15 transmits the captured image data to the circuit board 21 in order.

Summarizing the processing of the image sensor 15, the image sensor 15 captures an image of the contact surface 11 when the subject 10 is not present on the contact surface 11. Next, when the subject 10 comes into contact with the contact surface 11, the image sensor 15 captures an image of the surface of the subject 10 in contact with the contact surface 11. For example, when the subject 10 is a fingertip, the image sensor 15 captures an image of a fingertip fingerprint. Here, since the image data captured by the image sensor 15 is different from the image data when the subject 10 is not on the contact surface 11, the DSP of the image sensor 15 has the subject 10 on the contact surface 11. A signal indicating that is touching is transmitted to the circuit board 21. Then, when the subject 10 moves, the movement amount and movement direction of the subject 10 are calculated compared with the image data captured immediately before by the DSP, and a signal indicating the calculated movement amount and movement direction is transmitted to the circuit board 21. .

The light source 16 and the imaging element 15 are sealed with a transparent resin 20 made of a translucent resin. The shape of the transparent resin 20 is a substantially rectangular parallelepiped. The bottom surface of the transparent resin 20 is in close contact with and in contact with the upper surface of the circuit board 21, and concave portions that are in close contact with the light source 16 and the image sensor 15 are formed. As the translucent resin, for example, a thermosetting resin such as a silicone resin or an epoxy resin, or a thermoplastic resin such as acrylic or polycarbonate is used.

Thus, since the light source 16 and the image sensor 15 mounted on the circuit board 21 are respectively sealed with the transparent resin 20, the circuit board 21, the light source 16, the image sensor 15, and the transparent resin 20 are integrated. A substrate portion 26 is formed. Therefore, the number of parts of the optical pointing device 30 can be reduced, and the number of assembly processes can also be reduced. Accordingly, the manufacturing cost of the optical pointing device 30 can be reduced, and the optical pointing device 30 with high subject detection accuracy can be realized. Next, the structure of the cover part 24 is demonstrated. The cover part 24 protects each part and each element constituting the optical pointing device 30 such as the light source 16 and the imaging element 15. The cover part 24 is located on the upper side of the substrate part 26 and is in close contact with the side surface and the upper surface of the substrate part 26. The surface of the cover 24 that is on the negative side of the Z-axis and that is not exposed to the outside when mounted on the substrate 26 and formed as the optical pointing device 30 is referred to as the back of the cover 24. . That is, some of the contact surfaces (contact surfaces 24A, 24B, 24C) on the back surface of the cover portion 24 are in close contact with and in contact with the side surface and the upper surface of the substrate portion 26. The bottom surface (contact surface 24 </ b> C) of the cover portion 24 forms the same plane as the bottom surface of the substrate portion 26. The upper surface of the cover part 24 is parallel to the bottom surface (contact surface 24C) of the cover part 24 and the bottom surface of the substrate part 26, and both side surfaces of the cover part 24 are the upper surface of the cover part 24 and the cover part. It is formed by a surface having an angle with respect to the bottom surface (contact surface 24 </ b> C) of 24 and the bottom surface of the substrate portion 26. That is, as shown in FIG. 1, the optical pointing device 30 has a trapezoidal shape in the cross-sectional view. However, the shape is not limited to this, and the side surface may be perpendicular to the bottom surface.

A flange 25 is provided in the vicinity of the bottom of the side surface of the cover, and the optical pointing device of the present invention is mounted on the device and is pushed from the contact surface 11 of the cover 24 to the negative side of the Z axis by a subject such as a finger. In this case, the force generated in the positive direction of the Z-axis by a leaf spring-shaped contact switch provided on the bottom surface of the substrate portion 26 (not shown) is regulated at a certain position to ensure a certain stroke amount necessary as a pushbutton switch. Used for.

The contact surface 11 is a surface where the subject 10 is in contact with the optical pointing device 30. The contact surface 11 is an upper surface of the cover portion 24 and is located above the light source 16.

The bending element (prism) 12 is located above the light source 16 and below the contact surface 11, and forms a concave portion on the back surface of the cover portion 24 that is located on the back surface of the cover portion 24 and not in contact with the substrate portion 26. To do. The bending element 12 is formed with an inclined surface 13, and a narrow angle formed by the inclined surface 13 and the upper surface of the cover portion 24 is defined as an inclination angle θ. The bending element 12 refracts the light M emitted from the light source 16 on the inclined surface 13 and converts the path of the light M so as to go to the subject 10. Further, the bending element 12 totally reflects the light L reflected from the subject 10 by the inclined surface 13, and converts the path of the light L in the positive direction of the Y axis inside the cover portion 24. . The light L reflected from the subject 10 that has been totally reflected by the inclined surface 13 is directed to a reflection surface 17 described later. Thus, the inclined surface 13 of the bending element 12 transmits the light M and totally reflects the light L. Therefore, a material having a refractive index higher than the refractive index of the space above the light source 16 and between the cover portion 24 and the substrate portion 26 is used for the cover portion 24. For example, the cover 24 may be made of an air layer using a visible light absorption type polycarbonate resin or acrylic resin having a refractive index of about 1.5. That is, an aluminum reflective film or the like is not deposited on the inclined surface 13 of the bending element 12 in order to totally reflect the light L.

The imaging element (lens) 14 reflects the reflected light L from the subject 10 and forms an image of the subject 10 on the imaging element 15. The imaging element 14 is located above the image sensor 15 and on the positive side of the Y axis with respect to the image sensor 15, and is located on the back surface of the cover portion 24 that is not in contact with the substrate portion 26. A recess is formed. The imaging element 14 is formed with a toroidal surface having different curvatures in two orthogonal directions. The imaging element 14 reflects the light L reflected by the toroidal surface so as to form an image on the imaging element 15. In order to efficiently reflect the light L at the imaging element 14, a reflective film of metal (for example, aluminum, nickel, gold, silver, dielectric dichroic film, etc.) is deposited on the toroidal surface of the imaging element 14. . In the above description, the imaging element 14 is formed with a toroidal surface, but instead, for example, a reflector such as a spherical surface or an aspherical surface that can form an image on the imaging element 15. It is possible to use.

A stray light prevention prism for preventing stray light (stray light prevention) having a fine prism structure in the positive direction of the Y-axis from the end of the total reflection surface of the bending element (prism) 12 on the bottom surface (contact surface 24C) side of the cover portion 24. Part) 19A is formed. FIG. 2 is a perspective view from the bottom surface (contact surface 24C) side of the cover part 24. Similarly, the aperture 19B having a fine prism structure on both sides in the X-axis direction of the imaging element (lens) 14 is also shown. Is formed. These effects will be described with reference to FIG. FIG. 3 is a cross-sectional view of an optical pointing device schematically showing the effect of the stray light prevention structure.

FIG. 3A shows the optical pointing device 300 when the stray light preventing prism 19A is not provided in the optical pointing device 30 of FIG. 1, and FIG. 3B shows the optical pointing device 30 of FIG. The aperture 19B is also a structure for guiding stray light / disturbance light from outside the effective diameter in the X-axis direction of the imaging element 14 in a certain direction without entering the imaging element 15 using the same fine structure. Since the operation and effect are the same as the stray light prevention prism 19A, only the stray light prevention prism 19A will be described here. On the other hand, the light from the light source 16 is emitted with a certain spread from the light emitting point of the light source. Of the emitted light, the light M is scattered and reflected by the subject 10, becomes reflected light L, and enters the image sensor 15. However, light N1 and light N2 other than M are incident on the image sensor 15 as stray light without passing through the optical path of the imaging element 14 as shown in FIG. 3A where the stray light prevention prism is not formed. To do. In this case, the signal component obtained by subjecting the image picked up on the image pickup device 15 by the light passing through the optical path L to the image processing by the circuit board 21 can obtain signal information regarding the amount and direction of movement of the subject 10. On the other hand, a similar image by light passing through the optical path N1 and the optical path N2 can only obtain an image that does not move even if the subject 10 moves, so that not only signal information can be obtained but also a moving image. Since the images that do not move overlap and hide the movement of the images, accurate signal information cannot be obtained. (Hereinafter, light passing through the optical path L from which signal information can be obtained is referred to as signal light, and light other than signal light is referred to as noise light. In addition, noise light generated by a light source inside the optical pointing device is incident as stray light or from outside the optical pointing device. On the other hand, in FIG. 3B provided with the stray light preventing prism 19A, the stray light N1 and N2 generated in FIG. Since it changes to N2 ′ and is reflected outside the cover portion 24 and absorbed by the circuit board 21 or the like, it does not become noise light. The stray light prevention prism 19A and the aperture 19B are effective in addition to the light at the angles N1 and N2 of the light source 16 shown in FIG. 3, and not only the stray light from the light source 16 provided in the optical pointing device 30. It is also effective for disturbance light from outside the device.

The fine prism structure of the stray light preventing prism 19A and the aperture 19B may be appropriately set so that one side is about 30 to 100 μm and the forming angle is not in the undercut direction of the molding die. Although not shown in the drawing, a prism (aluminum, nickel, gold, silver, dielectric dichroic film, etc.) deposited film is provided on the stray light preventing prism 19A and the aperture 19B to give reflection characteristics. The stray light coming from an angle other than the total reflection angle is reflected in the opposite direction to the image sensor 15, or a light-shielding film (for example, paint or ink mixed with carbon black is formed by inkjet or printing) is used in place. By absorbing stray light, it is possible to enhance the stray light countermeasure effect. It is also possible to hybridize the fine prism structure for stray light countermeasures with the vapor deposition film or the light shielding film. For example, when there is a total reflection surface in the immediate vicinity of a place where it is desired to take countermeasures against stray light, stray light from a small portion that is not covered becomes a problem even if most of the surface is covered with a vapor deposition film or a light shielding film. This is because the formation accuracy of the film is as low as 0.5 mm to 1 m, and it is necessary to enlarge the mask so that the film is not attached to the total reflection surface. Since the value is one digit or more (about 10 μm), it is sufficiently possible to form a fine prism structure in a portion where this film cannot be formed.

Further, even if the concave / convex dimple structure other than the prism is used as the stray light prevention structure, the incident light is scattered on the spot, but the strong light does not reach the image pickup device 15, so that the stray light prevention action is achieved. Is enough.

The reflecting surface 17 reflects the light L so that the light L totally reflected by the inclined surface 13 is incident on the imaging element 14 and the light L reflected from the imaging element 14 is incident on the imaging element 15. It is. The reflection surface 17 is located above the image sensor 15 and on the upper surface of the cover portion 24. The reflection surface 17 is formed by depositing a reflection film on the upper surface of the cover portion 24. Since the reflective film forming the reflective surface 17 is exposed to the outside and can be seen well by the user, it is desirable to make the film as inconspicuous as possible in appearance. For example, when the wavelength of light emitted from the light source 16 is an infrared wavelength outside the visible wavelength (for example, 800 nm or more), the reflective film forming the reflective surface 17 is an infrared reflective film having the characteristics shown in FIG. If it is. FIG. 4A is a diagram showing the transmittance and reflectance at each wavelength, where the horizontal axis represents wavelength (nm) and the vertical axis represents transmittance and reflectance (%). The dotted line in the figure indicates the transmittance, and the solid line indicates the reflectance (the same applies to FIGS. 4B and 4C). As a specific example of the reflecting film, the reflecting film forming the reflecting surface 17 reflects infrared light having a wavelength band of 800 nm or more irradiated from the light source 16 and transmits light having a visible wavelength band of 800 nm or less. That's fine. As described above, the reflected light L from the subject 10 is efficiently reflected by appropriately setting the wavelength of the light emitted from the light source 16 and the reflectance and transmittance characteristics of the reflecting film forming the reflecting surface 17. And the reflective surface 17 which is not conspicuous in appearance can be formed.

Further, when the wavelength of light emitted from the light source 16 is an infrared wavelength outside the visible wavelength (for example, 800 nm or more), the cover portion 24 is preferably formed of a material having the characteristics shown in FIG. . Specifically, the material of the cover portion 24 may be a visible light absorption type polycarbonate resin or acrylic resin that transmits only infrared light. By forming the cover part 24 with such a material, visible light components can be blocked by the cover part 24 from unnecessary light entering from the outside of the cover part 24. As described above, by forming the reflection surface 17 that reflects infrared light, the infrared light component of the unnecessary light can be blocked by the reflection surface 17. By blocking unnecessary light incident on the optical pointing device 30, malfunction due to the unnecessary light can be prevented.

Furthermore, when coloring the surface of the cover unit 24, which is the surface of the optical pointing device 30, for example, a predetermined as shown in FIG. 4C is formed on the upper surface of the cover unit 24 and the upper surface of the reflection surface 17. What is necessary is just to coat with the material which reflects only the wavelength band of color (green in the example of illustration), and permeate | transmits the other wavelength. By coating the upper surface of the cover portion 24 and the upper surface of the reflecting surface 17 with a material having such characteristics, a desired color is applied to the surface of the optical pointing device 30 without impairing the optical characteristics of the optical pointing device 30. Can be attached.

The reflection surface 18 reflects the light L reflected from the imaging element 14 and reflected by the reflection surface 17 toward the reflection surface 17 again. The reflection surface 18 is located above the image sensor 15 and on the positive side of the Y axis from the image sensor 15, and is located on the back surface of the cover portion 24. The reflection surface 18 is formed by depositing a reflection film on the back surface of the cover portion 24. The reflective film forming the reflective surface 18 is preferably one that efficiently reflects light. For example, the reflecting surface 18 is formed by vapor-depositing a metal such as aluminum, nickel, gold, silver, or a dielectric dichroic film.

As described above, in the optical pointing device 30 of the present embodiment, the cover portion 24 is assembled above the substrate portion 26 with the transparent resin 20 side surface and the upper surface sealing the imaging element 15 in the substrate portion 26 as a reference. Yes. In the cover portion 24, contact surfaces 24 A and 24 B serving as a reference for making a decision on the transparent resin 20 of the substrate portion 26 are integrated with the contact surface 11, the bending element 12, the imaging element 14, and the flange 25. Is formed. Therefore, the contact surfaces 24A and 24B, the contact surfaces 11, the bending element 12, the imaging element 14, and the flange 25 are arranged with high mold tolerance.

Therefore, by bringing the contact surfaces 24A and 24B of the cover portion 24 into contact with the side surfaces and the upper surface of the transparent resin 20 of the substrate portion 26, the positional relationship with the cover portion 24 can be arranged with high accuracy. Therefore, since each unit and each element constituting the optical pointing device 30 can be arranged with high accuracy, the optical pointing device 30 with high detection accuracy of the subject 10 can be realized.

Here, the path through which the light emitted from the light source 16 reflects the subject 10 and enters the image sensor 15 will be described again. First, the light M emitted from the light source 16 is refracted and transmitted by the inclined surface 13 of the bending element 12 and reaches the contact surface 11. When the subject 10 is on the contact surface 11, the light M emitted from the light source 16 is scattered and reflected on the surface of the subject 10 in contact with the contact surface 11. The light L reflected by the surface of the subject 10 is totally reflected by the inclined surface 13 of the bending element 12, and the path changes in the positive direction of the Y axis. The light L totally reflected by the inclined surface 13 is reflected by the reflecting surface 17 and reaches the imaging element 14. Then, the light L is reflected back by the imaging element 14, is reflected one after another by the reflecting surface 17, the reflecting surface 18, and the reflecting surface 17 and enters the imaging device 15.

By adopting such an optical system, even if the optical path length of the optical system is increased and aberrations are suppressed, the length of the cover 24 in the Y-axis direction can be made smaller and smaller than the optical path length. It is possible to reduce the size.

As described above, in this embodiment, the contact surface 11, the bending element 12, the imaging element 14, the stray light prevention prism 19A, and the aperture 19B are integrally formed with the cover portion 24. Therefore, the number of parts of the optical pointing device 30 can be reduced, and the number of assembly processes can also be reduced. In addition, by forming a mold for forming the cover portion 24 with high accuracy, the inclined surface 13 and the imaging element 14, the stray light prevention prism 19A and the aperture 19B of the bending element 12 can be manufactured with high accuracy, and The positional relationship among the contact surface 11, the bending element 12, the imaging element 14, the stray light prevention prism 19A and the aperture 19B can also be arranged with mold accuracy. Accordingly, the manufacturing cost of the optical pointing device 30 can be reduced, and the optical pointing device 30 with high subject detection accuracy can be realized.

Further, when assembling the contact surface 11, the bending element 12, and the imaging element 14 as separate parts, shapes such as an abutting surface for assembly and a fitting shape are required. Since it cannot be formed, a separate aperture such as a light-shielding sheet and stray light prevention means are required, so a contact surface for assembling them and a shape such as a fitting shape are also required, and a margin for adjusting the relative positional relationship between them. It is necessary to ensure. When integrated, the above shape is not necessary, and if there is a minimum required optical surface, it is not necessary to secure an adjustment margin, and the contact surface 11, the bending element 12 and the imaging element 14, the stray light prevention prism 19A, and the aperture The thickness of the cover part 24 including 19B can be reduced. Therefore, the thickness of the optical pointing device 30 can be reduced.

In the present embodiment, the cover portion 24 is assembled above the substrate portion 26 with the transparent resin 20 side surface and the upper surface of the substrate portion 26 as a reference. This will be described with reference to FIG. FIG. 5 is a schematic diagram for explaining how to assemble the optical pointing device according to the first embodiment of the present invention. The cover portion 24 includes contact surfaces 24A, 24B, and 24C that serve as a reference for making a decision on the transparent resin 20 of the substrate portion 26. The contact surface 11, the bending element 12, the imaging element 14, and the stray light prevention prism 19A. The aperture 19B and the flange 25 are integrally formed. Therefore, the contact surfaces 24A, 24B, and 24C, the contact surfaces 11, the bending element 12, the imaging element 14, the stray light prevention prism 19A, the aperture 19B, and the flange 25 are arranged with high precision with mold tolerances. . The cover portion 24 is arranged as shown by an arrow P in FIG. 5, and the contact surfaces 24A, 24B, and 24C of the cover portion 24 are brought into contact with the side surface and the upper surface (surface) of the transparent resin 20 of the substrate portion 26. The positional relationship with the cover part 24 can be arranged with high accuracy. Therefore, since each part and each element constituting the optical pointing device 30 can be arranged with high accuracy, the optical pointing device 30 with high detection accuracy of the subject 10 can be realized.

Further, a light shielding resin may be resin-sealed on the side surface of the transparent resin 20 and the upper surface excluding the lens portion. Further, a light shielding resin may be resin-sealed on the side surface of the transparent resin 20 and on the upper surface of the transparent resin 20 excluding a portion where the reflected light L from the subject is transmitted. As the light-shielding resin, for example, a thermosetting resin such as a silicone resin or an epoxy resin, or a thermoplastic resin such as acrylic or polycarbonate is used, similarly to the light-transmitting resin. However, unlike the light-transmitting resin, the light-blocking resin includes carbon black. In this way, by sealing the light-shielding resin around the transparent resin 20, the light emitted from the light source 16 is reflected directly or at a place other than the subject 10 and enters the image sensor 15. Can be prevented. It is possible to prevent so-called stray light that is not reflected light L from the subject 10 from entering the image sensor 15. Therefore, malfunction of the optical pointing device 30 due to stray light can be prevented, and the subject 10 can be detected with high accuracy.

As described above, in the optical pointing device 30 of the present embodiment, the light emitted from the light source 16 does not pass through the imaging element 14 on the back surface (the surface facing the light source 16 and the image sensor 15) of the cover portion 24. A stray light prevention prism 19A that changes the path of light incident on the image sensor 15 is provided. In other words, the cover 24 is provided with a countermeasure (stray light countermeasure) against the light emitted from the light source 16 and directly incident on the imaging element 15 without being reflected by the subject 10. Thus, when light that has not been reflected by the subject 10 that causes stray light among the light emitted from the light source 16 reaches the stray light prevention prism 19A, the path is changed when the light is emitted from the stray light prevention prism 19A. Therefore, the light emitted from the light source 16 can be prevented from becoming stray light without being reflected by the subject 10.

Further, since the stray light preventing prism 19A is formed on the back surface of the cover portion 24, stray light can be prevented even in the thin optical pointing device 30.

Therefore, even in a thin optical pointing device, it is possible to provide an optical pointing device 30 that can reduce the influence of stray light on the image data captured by the image sensor 15.

Moreover, in the optical pointing device 30, the contact surface 11, the bending element 12, the imaging element 14, the stray light prevention prism 19A, and the aperture 19B are integrally formed with the cover portion 24. That is, an optical system that is an essential component of the optical pointing device 30 is integrally formed. As a result, even if the optical path length of the optical system is increased and aberrations are suppressed, the length of the cover portion 24 in the vertical direction can be reduced as compared with the optical path length. Therefore, the optical pointing device 30 can be further reduced in size and thickness. Further, by integrally molding, the cover portion 24 can be assembled with high accuracy and the number of parts can be reduced.

[Second Embodiment]
A second embodiment of the present invention will be described with reference to FIG. FIG. 6 is a schematic sectional view of an optical pointing device 30a according to the second embodiment. In the second embodiment, a diffractive element 12 ′ is arranged instead of the bending element 12 that totally reflects the reflected light L in the horizontal direction in the first embodiment. Hereinafter, differences from the first embodiment due to the arrangement of the diffraction element 12 ′ in the second embodiment will be described. In the second embodiment, the description of the same configuration as in the first embodiment is omitted.

As shown in FIG. 6, in the substrate portion 26, the transparent resin 20 that seals the light source 16 is such that the negative side surface of the Y axis is not flush with the side surface of the circuit board 21, and the negative side surface of the Y axis is It is located on the positive side of the Y axis from the side surface of the circuit board 21. The light M emitted from the light source 16 is transmitted and refracted on the back surface of the cover portion 24 via the lens portion 27 of the transparent resin 20 and reaches the contact surface 11.

The cover 24 includes the contact surface 11, the diffraction element 12 ', the imaging element 14, the stray light prevention prism 19A, the aperture 19B, and the reflection surfaces 17 and 18. The cover portion 24 is located above the substrate portion 26 and is in close contact with the X-axis positive side surface, the Y-axis positive side surface, and the upper surface of the transparent resin 20 that seals the imaging device 15 and the light source 16. It touches.

The diffractive element 12 ′ is located above the light source 16 and below the contact surface 11, and at a portion that does not contact the substrate portion 26 on the back surface (contact surface 24 </ b> C) of the cover portion 24. The diffractive element 12 ′ reflects the light L reflected from the subject 10, and converts the path of the light L in the positive direction of the Y axis inside the cover portion 24. The light L reflected from the subject 10 and reflected by the diffraction element 12 ′ travels toward the reflecting surface 17.

A specific shape of the diffraction element 12 'will be described with reference to FIG. FIG. 7A is a schematic configuration diagram showing a cross-sectional shape of the diffraction element 12 ′. The diffractive element 12 'is a reflective diffractive element that uses + 1st order reflected diffracted light. As for the shape of the diffractive element 12 ′, for example, it is desirable that the cross-sectional shape as shown in FIG. By using the blazed diffractive element 12 'shown in FIG. 7A, the light utilization efficiency can be improved, and the 0th order light, the −1st order light and the higher order diffracted light that become stray light can be suppressed. Therefore, in the optical pointing device 30a, it is possible to prevent the imaging performance of the optical system from deteriorating.

In order to improve the reflectance, a reflective film al (for example, aluminum, silver, gold, dielectric dichroic film, etc.) is vapor-deposited on the outer surface (surface on the negative side of the Z axis) of the diffraction element 12 ′. It is desirable. Here, as shown in FIG. 7A, the blazed groove depth (length in the Z direction) of the diffractive element 12 'is t. The groove depth t is desirably a depth that maximizes the + 1st order diffraction efficiency. For example, when the refractive index n of the cover 24 and the wavelength of light emitted from the light source 16 are λ, it is desirable to set t = λ / (2n).

The blazed groove pattern of the diffractive element 12 'has a straight regular pitch as shown in FIG. 7B, and is desirably as fine as possible in order to maximize the diffraction angle. However, in terms of manufacturing, it is most advantageous in terms of cost to form and mold the groove by cutting using a cutting tool for the mold. Therefore, in consideration of the range in which the grooves can be accurately manufactured by cutting, it is desirable to design the groove pitch of the diffraction element 12 'between 0.8 and 3.0 μm.

Further, in order to improve the imaging performance for capturing the image of the subject 10 projected onto the image sensor 15, the groove pattern of the diffraction element 12 ′ is curved as shown in FIG. Distortion can be corrected. Further, as shown in FIG. 7D, the groove pitch of the diffractive element 12 ′ is not an equal pitch but a pattern in which the pitch gradually changes, and the diffractive element 12 ′ is designed to have a lens effect in a certain direction. You may do it. In this case, it is possible to correct aberration that occurs due to the difference in focal length between the X-axis direction and the Y-axis direction on the image sensor 15.

Further, as shown in FIG. 5E, both the image distortion and astigmatism (astigmatism) can be corrected by making the groove pattern of the diffractive element 12 'a curved and unequal pitch pattern. .

As another specific example of the diffractive element 12 ', a reflective Fresnel lens may be used for the diffractive element 12'. A specific shape of the Fresnel lens is shown in FIG. FIG. 8 is a schematic configuration diagram showing a cross-sectional shape of a diffraction element 12 ′ that is a Fresnel lens, as in FIG. 7A. As shown in the figure, the cross-sectional shape of the Fresnel lens is a blaze shape. In order to improve the reflectance, it is desirable that a reflective film al (for example, aluminum, silver, gold, dielectric dichroic film, etc.) is deposited on the outer surface of the diffraction element 12 '. When a Fresnel lens is used for the diffractive element 12 ′, the thickness of the cover portion 24 can be made uniform compared to the case where a prism or a bulk lens is formed on a part of the cover portion 24. Therefore, it is possible to reduce the thickness of the optical pointing device 30a while increasing the strength of the cover portion 24.

Further, if a hologram lens is used for the diffraction element 12 ′, aberrations that cannot be corrected by a normal lens can be corrected, so that the imaging performance is improved, and the image of the subject 10 is projected clearly on the imaging element 15. Can do.

As described above, when the diffractive element 12 ′ is used to reflect the light L reflected from the subject 10 in the horizontal direction, compared with the case where the bending element (prism) 12 is formed in the cover part 24, The thickness can be made uniform. Therefore, it is possible to reduce the thickness while increasing the strength of the cover portion 24. In addition, the light irradiated from the light source 16 can be irradiated to the contact surface 11 with uniform light intensity.

Further, in the conventional optical pointing device that bends the reflected light L from the subject 10 in the horizontal direction (for example, the configuration of Patent Document 1 above), the size of the bending element 12, particularly the length in the Z-axis direction, is the same as that of the optical pointing device. It greatly affects the thickness. That is, in order to design the optical pointing device thin, it is important to reduce the length of the bending element 12 in the Z-axis direction. However, the size of the bending element 12 cannot be designed freely, and the size of the bending element 12 depends on the size of the contact surface 11. And in order to detect the pattern on the contact surface 11, the contact surface 11 must have a certain amount of area. Therefore, if the area of the contact surface 11 is to be secured, the bending element 12 inevitably increases, and the thickness of the optical pointing device 30 (size in the Z-axis direction) cannot be reduced.

In the second embodiment, the optical pointing device 30a is made thinner than the first embodiment by using a diffractive element 12 'that can be smaller in length in the Z-axis direction than the bending element 12 instead of the bending element 12. Can be achieved.

In the second embodiment, similarly to the method shown in the first embodiment, a cover is provided above the substrate portion 26 with reference to the side surface and the upper surface of the transparent resin 20 that seals the imaging element 15 in the substrate portion 26. The part 24 is assembled. That is, a part of the contact surface (contact surfaces 24A, 24B, 24C) on the back surface of the cover portion 24, the side surface on the positive side of the X axis in the transparent resin 20 that seals the image sensor 15 and the light source 16, and the Y axis The cover portion 24 is assembled above the substrate portion 26 with reference to the positive side surface and the upper surface. Therefore, the positional relationship between the substrate part 26 and the cover part 24 can be arranged with high accuracy. Therefore, since each part and each element constituting the optical pointing device 30a can be arranged with high accuracy, the optical pointing device 30a with high detection accuracy of the subject 10 can be realized.

[Third Embodiment]
A third embodiment of the present invention will be described with reference to FIG. FIG. 9 is a schematic sectional view of an optical pointing device 30b according to the third embodiment. In the third embodiment, in addition to the first and second embodiments, a diffractive element 12 ′ is arranged instead of the bending element 12 that totally reflects the reflected light L of the optical pointing device in the horizontal direction. Hereinafter, differences from the first embodiment due to the arrangement of the diffraction element 12 ′ in the third embodiment will be described. In the third embodiment, the same configuration as that of the first embodiment will be described for the sake of explanation. However, the changed portion and the effect are the same as those of the second embodiment, and the same effect is obtained. The description of the same parts as those in the first embodiment is omitted.

As shown in the drawing, in the optical pointing device 30b, light shielding films 28A and 28B for shielding light from outside the device are formed on the contact surface 11 of the cover portion 24. The window area indicated by P in the figure is a portion where the light shielding film is not formed, the subject 10 is in contact with the contact surface 11 of the cover 24, and the light from the light source 16 is shielded by the light shielding films 28A and 28B. This is an area where the subject 10 can be reached without being done.

In the light coming from the outside of the pointing device 30b of the present embodiment, the light from other than the object surface on the cover contact surface that can obtain good characteristics in the imaging element 14 is multiple-reflected inside the cover unit 24, and the image sensor 15, the signal light passing through the optical system including the imaging element 14 of the cover 24 becomes disturbance light and the contrast of the image captured by the imaging element 15 is lowered. Of course, even when the subject 10 is a finger even when the light comes from outside the apparatus, the light transmitted through the finger enters the cover portion 24 from the contact surface and passes through the optical system including the imaging element 14. However, since the amount of disturbance light is larger, the contrast of the image is lowered as a result.

However, according to the above configuration, since the influence of the disturbance light can be suppressed and only the signal light can be enhanced, the contrast of an image photographed by the imaging element is improved.

The light shielding films 28A and 28B may be reflective films that specifically reflect disturbance light (for example, aluminum, silver, gold, dielectric dichroic film, etc.), and absorption films that absorb disturbance light in situ (for example, , Paint or ink mixed with carbon black). In the case of a vapor deposition film, vapor deposition may be performed by masking the window area, and in the case of an absorption film, it may be formed by ink jet or pad printing.

The area where the light-shielding film is formed is only required to be formed in the positive direction of the Z axis with respect to the flange 25 protruding from the device housing, since the flange 25 is disposed inside the device housing. Further, the casing of the device has a thickness, and disturbance light is shielded by the thickness. Therefore, the light shielding film 28B is not always necessary, and measures such as forming only the light shielding film 28A may be appropriately taken.

[Fourth Embodiment]
Finally, an electronic device equipped with an optical pointing device will be described with reference to FIG. FIG. 10 is a diagram illustrating an appearance of the mobile phone 100 on which the optical pointing device 107 is mounted. 10A is a front view of the mobile phone 100, FIG. 10B is a rear view of the mobile phone 100, and FIG. 10C is a side view of the mobile phone 100. Although FIG. 10 shows an example in which the electronic device is a mobile phone, the present invention is not limited to this. The electronic device may be, for example, a PC (particularly a mobile PC), a PDA, a game machine, a remote controller such as a television, or the like.

As shown in FIG. 10, the mobile phone 100 includes a monitor-side casing 101 and an operation-side casing 102. The monitor-side casing 101 includes a monitor unit 105 and a speaker unit 106, and the operation-side casing 102 includes a microphone unit 103, a numeric keypad 104, and an optical pointing device 107. Any of the optical pointing devices 30, 30a, 30b, and 30c described in the first to fourth embodiments can be applied to the optical pointing device 107 mounted on the mobile phone 100.

In the present embodiment, the optical pointing device 107 is arranged on the upper part of the numeric keypad 104 as shown in FIG. 10A. However, the arrangement method and the direction of the optical pointing device 107 are not limited thereto. It is not done.

The speaker unit 106 outputs audio information to the outside, and the microphone unit 103 inputs audio information to the mobile phone 100. The monitor unit 105 outputs video information. In the present embodiment, the monitor unit 105 displays input information from the optical pointing device 107.

Note that, as shown in FIGS. 10A to 10C, the cellular phone 100 according to the present embodiment includes an upper casing (monitor-side casing 101) and a lower casing (operation-side casing 102). As an example, a so-called foldable mobile phone 100 is connected to each other via a hinge. Since the folding type is the mainstream of the cellular phone 100, the folding type cellular phone is given as an example in the present embodiment, and the cellular phone 100 on which the optical pointing device 107 can be mounted is foldable. It is not limited.

In recent years, a folding mobile phone 100 having a thickness of 10 mm or less in a folded state has also appeared. If the portability of the mobile phone 100 is taken into consideration, its thickness is an extremely important factor. In the operation-side casing 102 shown in FIG. 10, components that determine the thickness of the operation-side casing 102 except for an internal circuit board (not shown) are a microphone unit 103, a numeric keypad 104, and an optical pointing device 107. Among these, the thickness of the optical pointing device 107 is the largest, and the thinning of the optical pointing device 107 directly leads to the thinning of the mobile phone 100. Therefore, the optical pointing device of the present invention that can be thinned as described above is a preferred invention for an electronic device that needs to be thinned, such as the cellular phone 100.

In the above-described embodiments, the optical pointing device including the light source 16 has been described. However, instead of the light source 16, even in the case of external light such as sunlight, an optical pointing device that operates without degrading performance can be obtained by the configuration of the present invention.

Further, in each of the above-described embodiments, the optical pointing device using the cover portion 24 (light guide type optical member) has been described. However, the same effect can be obtained by providing the stray light preventing unit of the present invention in a conventional optical pointing device (for example, the configuration of Patent Documents 2 and 3) that does not use the cover unit 24.

The present invention can also be expressed as follows.

An optical pointing device according to the present invention comprises an imaging means for forming an image of scattered light from a subject, and receiving the scattered light from the subject and continuously taking images of the surface of the subject at regular intervals. An image sensor that captures an image as image data, and a calculation unit that calculates the moving direction and amount of movement of the subject by comparing the image data captured by the image sensor with the image data captured by the image sensor immediately before, An optical pointing device comprising a cover member that covers the imaging means, the imaging device, and the calculation unit, wherein the cover member has at least a contact surface that contacts the subject, and the imaging means; , An optical path deflecting unit that deflects the direction of scattered light from the subject incident from the contact surface and guides it to the imaging unit, a stray light preventing unit that prevents stray light, and the imaging unit Apertures to be granted, may be integrally formed.

According to the above configuration, since the cover portion, the optical path deflecting unit, the imaging unit, the stray light preventing unit, and the aperture are integrally formed, the number of components constituting the optical pointing device can be reduced. it can. Therefore, the number of assembling steps can be reduced in the manufacturing process of the optical pointing device. Therefore, it is possible to suppress an assembly error that occurs when assembling each component. In addition, by creating a mold for molding the cover part with high precision, the shape of the optical path deflecting means, imaging means, stray light preventing means and the aperture itself can be manufactured with high precision, and the contact surface can be bent. The positional relationship between the element and the imaging element and the positional relationship between the imaging means and the aperture can be arranged with high accuracy without variation. Accordingly, the manufacturing cost of the optical pointing device can be reduced, the detection accuracy of the subject is high, and the S / N (Signal / Noise: Signal here means from the contact surface to the optical path deflecting means and the imaging means. This is an effect that it is possible to realize an optical pointing device having a high ratio of scattered light components from the subject incident on the image sensor through the noise, and Noise being an unnecessary light component incident on the image sensor through other optical paths. Play.

Therefore, according to the above configuration, it is possible to reduce the manufacturing cost of the optical pointing device and to realize an optical pointing device with high subject detection accuracy.

Further, the stray light preventing means and the aperture of the optical pointing device according to the present invention may have a fine structure.

According to the above configuration, the stray light preventing means and the aperture can be integrally formed with a mold or the like together with the optical path deflecting means and the imaging means. The stray light preventing means and the aperture can be formed integrally with the cover member by the technique of insert molding, but separate parts are required, and the position of these parts also shifts during insert molding. However, if it has a fine structure, high-precision arrangement is possible without the need for separate parts.

Also, the stray light preventing means and the aperture fine structure of the optical pointing device according to the present invention may be a prism structure.

As the fine structure of the stray light prevention means and aperture, a fine uneven dimple structure is also effective, but in the dimple structure, the stray light component may be scattered there and reflected again on another surface of the cover part and incident on the image sensor. Is not small. However, according to the above configuration, since the planar portion of the prism reflects stray light in a specific direction, it is less likely to be reflected again on another surface of the cover portion and enter the imaging device. Will improve.

Further, the stray light preventing means and the aperture of the optical pointing device according to the present invention may be provided with a reflection performance by a deposited film in which a metal or a dielectric is deposited.

The incident angle of the stray light incident on the stray light prevention means and the aperture is not constant, and it is incident from various directions, but when the reflection performance is not given, there is a certain condition that meets the total reflection condition coming from the stray light prevention means and the aperture structure Although only stray light with a range of angles can be reflected in a specific direction, the reflection range by the deposited film can be increased to widen the range of angles that can be reflected, thereby improving stray light prevention performance.

Further, the imaging means of the optical pointing device according to the present invention may be configured by any one of a spherical surface, an aspherical surface, and a toroidal surface.

Based on optical aberrations such as spherical aberration and coma generated from the optical system configuration of the optical pointing device, and the amount of distortion of the image projected on the image sensor, the curvature of the imaging means is spherical, aspherical, or toroidal. By appropriately setting the surface, the optical characteristics of the optical system of the optical pointing device can be further improved.

Further, the imaging means of the optical pointing device according to the present invention may be provided with a reflection performance by a deposited film obtained by depositing a metal, a dielectric or the like.

With the above-described configuration, the light pointing device can be reduced in size in the plane direction, in which scattered light from the subject is reflected by the imaging means and returned to the subject direction.

Further, the optical path deflecting means of the optical pointing device according to the present invention is constituted by any of a total reflection surface, a deposition film reflection surface on which a metal or a dielectric is deposited, a reflection diffraction grating surface or a reflection hologram surface. May be.

When the optical path deflecting means is a total reflection surface, the light projected on the image sensor is the highest in light use efficiency with respect to a vapor deposition reflection surface, a reflection type diffraction grating surface and a reflection type hologram surface, which will be described later. Since it becomes brighter, the S / N ratio is improved. Further, when the optical path deflecting means is a vapor deposition reflecting surface, the light use efficiency is lowered, but the light incident on the optical path deflecting means can be reliably reflected.

The surface of the cover where the contact surface is located may contact the subject. When the subject contacts a location other than the contact surface, the reflected light is reflected when the reflected light is reflected at the location where the subject is in contact. Is reflected on the surface of the object, not reflected on the surface of the cover, and thus the reflected light path is shifted. Therefore, by arranging the vapor deposition reflective film at this location, it is possible to suppress the occurrence of deviation of the path of the reflected light, the imaging performance of the imaging element is improved, and the imaging element captures the image of the subject. A clear image can be taken.

Further, when the optical path deflecting means is a reflection type diffraction element and a reflection type hologram surface, the light use efficiency is lowered as in the case of the vapor deposition film reflection surface, but the optical path deflection is performed in the direction opposite to the contact surface of the cover part. When forming the means, the cover portion including the function of the optical path deflecting means can be formed without forming a concave portion therefor. Therefore, the thickness of the entire cover portion can be made uniform from the cover portion including the bending element of the concave portion, and the cover portion can be thinned while increasing the strength of the cover portion. In addition, when the deflecting means is a reflection hologram surface, it can also have a role of correcting aberrations that cannot be corrected by the imaging means, so that the imaging element that reflects the reflected light of the bending element can be used. The imaging performance is improved, and the image pickup device can pick up a subject image clearly.

The performance of the optical pointing device can be improved by appropriately using each of these reflecting surfaces.

The optical pointing device according to the present invention may further include a light source covered with the cover member, and the scattered light from the subject may be generated based on light emitted from the light source.

According to the above configuration, the scattered light is generated based on light emitted from the light source and reflected by the subject. Therefore, the angle at which the light emitted from the light source irradiates the subject can be aligned to some extent. Therefore, even when the illuminance of the light source is lowered, a sufficient amount of light for detecting the subject can be maintained. Therefore, since the amount of current supplied to the light source can be reduced, the amount of current consumed by the optical pointing device can be suppressed.

Further, a light shielding performance for shielding light from the outside of the apparatus may be imparted to a region other than the contact surface of the cover member located on the object plane in the imaging means of the optical pointing device according to the present invention.

In the light coming from the outside of the optical pointing device according to the present invention, the light from other than the object surface on the cover contact surface that provides good characteristics in the imaging means becomes disturbance light for the optical pointing device.

According to the above configuration, since the influence of the disturbance light can be suppressed, the contrast of an image photographed by the image sensor is improved.

In the optical pointing device according to the present invention, each of the transparent resins in which the light source and the imaging element are resin-sealed has a substantially rectangular parallelepiped shape, and one side surface of the transparent resin in which the light source is resin-sealed is One side surface of the other transparent resin disposed on the same plane as the one side surface of the substrate and resin-sealed with the imaging element is disposed on the same plane as the other side surface of the substrate, The cover portion is disposed on the upper side of the substrate with reference to the front surface, both side surfaces of the substrate, and one side surface of the transparent resin in which the light source and the imaging element in the same plane are sealed with resin. Also good.

According to the above configuration, the upper surface of each of the transparent resins, both side surfaces of the substrate, and one side surface of the transparent resin that is disposed on the same plane as the light source and the imaging element. The cover portion is disposed on the upper side of the substrate with reference to. Therefore, the positional relationship among the contact surface, the light source, the imaging element, the bending element, and the imaging element can be arranged with high accuracy. Therefore, an optical pointing device with high subject detection accuracy can be realized.

Also, an electronic apparatus according to the present invention includes the above optical pointing device.

According to the above configuration, the electronic apparatus includes the optical pointing device that can be easily thinned. When the optical pointing device is mounted, the thickness of the optical pointing device greatly affects the thickness of the electronic device. Therefore, even if the optical pointing device is provided, the electronic device can be thinned.

[Fifth Embodiment]
A fifth embodiment of the present invention will be described with reference to FIGS. FIG. 11 is a schematic cross-sectional structure diagram showing an optical pointing device 30α in the fifth embodiment.

As shown in FIG. 11, the optical pointing device 30α of the present embodiment includes a substrate portion 26α and a cover portion 24α as a light guide type optical member. The board portion 26α includes a circuit board 21α, a light source 16α, an image sensor 15α, and a transparent resin 20α. The cover portion 24α includes a contact surface 11α, an optical path changing means for forming the inclined surface 13α, a bending element 12α as a prism, an imaging element 14α as an imaging reflecting portion, and reflecting surfaces 17α and 18α. The subject 10α in contact with the contact surface 11α of the cover 24α is a subject such as a fingertip, and is an object for which the optical pointing device 30α detects the movement of the finger fingerprint. Here, in order to make it easy to understand the state of the subject 10α with respect to the optical pointing device 30α, the subject 10α is shown small for convenience with respect to the optical pointing device 30α.

Here, the thickness direction (vertical direction in FIG. 11) of the optical pointing device 30α is defined as the Z axis, and the width direction (horizontal direction in FIG. 11) of the optical pointing device 30α is defined as the Y axis. The direction from the lower part to the upper part of the optical pointing device 30α is the positive direction of the Z axis, and the direction from the light source 16α to the image sensor 15α is the positive direction of the Y axis. The positive direction of the Z axis is also called the vertical direction, and the positive direction of the Y axis is also called the horizontal direction. Although not shown, the depth direction of the optical pointing device 30α is defined as the X axis, and the direction from the back side to the near side of the optical pointing device 30α illustrated in FIG. 11 is defined as the positive direction of the X axis.

First, the configuration of the substrate part 26α will be described.

In the board portion 26α of the present embodiment, the light source 16α and the image sensor 15α are mounted on one circuit board 21α. The light source 16α and the image sensor 15α are electrically connected to the circuit board 21α by wire bonding or flip chip mounting. A circuit is formed on the circuit board 21α. The circuit controls the light emission timing of the light source 16α or detects the movement of the subject 10α in response to an electric signal output from the image sensor 15α. The circuit board 21α has a planar shape made of the same material, and is made of, for example, a printed board or a lead frame.

The light source 16α emits light toward the contact surface 11α of the cover portion 24α. The irradiation light Mα emitted from the light source 16α is refracted by the bending element 12α of the cover portion 24α through the transparent resin 20α, the traveling direction is changed, and reaches the contact surface 11α. That is, the irradiation light Mα is incident on the contact surface 11α from an oblique direction, that is, at a certain incident angle with respect to the contact surface.

As will be described later, the cover 24α is made of a material having a refractive index larger than that of air. Therefore, when the subject 10α is not on the contact surface 11α, the irradiation light Mα that reaches the contact surface 11α is partially a contact surface. 11α is transmitted, and the remaining part is reflected by the contact surface 11α. At this time, when the incident angle of the irradiation light Mα with respect to the contact surface 11α satisfies the condition of total reflection, the irradiation light Mα does not pass through the contact surface 11α but is reflected by the contact surface 11α and goes into the cover portion 24α.

On the other hand, when the subject 10α is on the contact surface 11α, the irradiation light Mα is reflected by the surface of the subject 10α in contact with the contact surface 11α and is incident on the cover portion 24α. The light source 16α is realized by a light source such as an LED (Light Emitting Diode), and is preferably realized by an infrared light emitting diode with high luminance.

The image sensor 15α receives reflected light Lα reflected by the subject 10α irradiated by the light source 16α, forms an image on the contact surface 11α based on the received light, and converts it into image data. Specifically, the image pickup device 15α includes an image sensor such as a CMOS (Complementary Metal Oxide Semiconductor) or a CCD (Charge Coupled Device). The image sensor 15α includes a DSP (Digital Signal Processor: calculation unit) (not shown), and takes the received irradiation light Mα as image data into the DSP. The image pickup device 15α continues to take images on the contact surface 11α at regular intervals in accordance with instructions from the circuit board 21α.

When the subject 10α in contact with the contact surface 11α moves, the image captured by the image sensor 15α is different from the image captured immediately before. In the DSP, the image sensor 15α compares the values of the same portion of the captured image data with the immediately preceding image data, and calculates the movement amount and movement direction of the subject 10α. That is, when the subject 10α on the contact surface 11α moves, the captured image data is image data indicating a value deviated by a predetermined amount with respect to the image data captured immediately before. In the DSP, the image sensor 15α calculates the moving amount and moving direction of the subject 10α based on the predetermined amount. The imaging element 15α outputs the calculated movement amount and movement direction to the circuit board 21α as electric signals. The DSP may be included in the circuit board 21α, not in the image sensor 15α. In that case, the imaging device 15α transmits the captured image data to the circuit board 21α in order.

Summarizing the processing of the image sensor 15α, the image sensor 15α captures an image of the contact surface 11α when there is no subject 10α on the contact surface 11α. Next, when the subject 10α comes into contact with the contact surface 11α, the imaging element 15α captures an image of the surface of the subject 10α that is in contact with the contact surface 11α. For example, when the subject 10α is a fingertip, the imaging element 15α captures an image of a fingertip fingerprint. Here, since the image data captured by the image sensor 15α is different from the image data when the subject 10α is not on the contact surface 11α, the DSP of the image sensor 15α has the subject 10α on the contact surface 11α. Is sent to the circuit board 21α. Then, when the subject 10α moves, the movement amount and movement direction of the subject 10α are calculated compared with the image data captured immediately before by the DSP, and a signal indicating the calculated movement amount and movement direction is transmitted to the circuit board 21α. .

The surroundings of the light source 16α and the image sensor 15α are sealed with a transparent resin 20α that is a translucent resin. The shape of the transparent resin 20α is a substantially rectangular parallelepiped. The bottom surface of the transparent resin 20α is in close contact with and in contact with the upper surface of the circuit board 21α, and concave portions that are in close contact with the light source 16α and the imaging element 15α are formed. As the translucent resin constituting the transparent resin 20α, for example, a thermosetting resin such as a silicone resin or an epoxy resin, or a thermoplastic resin such as acrylic or polycarbonate is used.

Thus, since the light source 16α and the image sensor 15α mounted on the circuit board 21α are respectively sealed with the transparent resin 20α, the circuit board 21α, the light source 16α, the image sensor 15α, and the transparent resin 20α are integrated. A substrate portion 26α is formed. Therefore, the number of parts of the optical pointing device 30α can be reduced, and the number of assembly steps can also be reduced. Therefore, the manufacturing cost of the optical pointing device 30α can be reduced, and the optical pointing device 30α with high detection accuracy of the subject 10α can be realized.

Next, the configuration of the cover part 24α will be described.

The cover part 24α protects each part and each element constituting the optical pointing device 30α such as the light source 16α and the imaging element 15α. The cover portion 24α is positioned above the substrate portion 26α and is in close contact with and in contact with the side surface and the upper surface of the substrate portion 26α. That is, some of the contact surfaces 24aα and 24bα on the back surface of the cover portion 24α are in close contact with and in contact with the side surface and the upper surface of the substrate portion 26α. In the present embodiment, the surface portion on the negative side of the Z axis in the cover portion 24α that is not exposed to the outside when mounted on the substrate portion 26α and formed as the optical pointing device 30α. This is referred to as the back surface of the cover portion 24α.

Further, the bottom surface 24cα of the cover portion 24α forms the same plane as the bottom surface 26aα of the substrate portion 26α. Further, the upper surface of the cover portion 24α, the contact surface 24bα of the cover portion 24α, the bottom surface 26aα of the substrate portion 26α and the bottom surface 24cα of the cover portion 24α are parallel to each other, and both side surfaces of the cover portion 24α are covered. The upper surface of the portion 24α, the contact surface 24bα of the cover portion 24α, the bottom surface 26aα of the substrate portion 26α, and the surface having an angle with respect to the bottom surface 24cα of the cover portion 24α are formed. That is, as shown in FIG. 11, in the cross-sectional view of the optical pointing device 30α, the cover portion 24α has a trapezoidal shape. However, the cover portion 24α is not limited to this shape, and the side surface may be perpendicular to the bottom surface 24cα.

A flange 25α is provided in the vicinity of the bottom of the side surface of the cover portion 24α, and the optical pointing device 30α of the present embodiment is mounted on the electronic device, and the contact surface 11α to Z of the cover portion 24α is moved by the subject 10α such as a finger. A pushbutton switch that restricts the force generated in the positive direction side of the Z-axis at a certain position by a leaf spring-shaped contact switch (not shown) provided on the bottom surface 26aα of the base plate portion 26α when pressed to the negative direction side of the shaft. Used to ensure a certain amount of stroke required.

The contact surface 11α in the cover portion 24α is a surface where the subject 10α is in contact with the optical pointing device 30α. The contact surface 11α is located above the light source 16α on the upper surface of the cover portion 24α.

The bending element 12α is a prism, and is located above the light source 16α and below the contact surface 11α, and is located on the back surface of the cover portion 24α and not on the substrate portion 26α. Are formed. The bending element 12α has an inclined surface 13α, and a narrow angle formed by the inclined surface 13α and the upper surface of the cover portion 24α is defined as an inclination angle θα. The bending element 12α refracts the irradiation light Mα emitted from the light source 16α by the inclined surface 13α and converts the path of the irradiation light Mα so as to go to the subject 10α. Further, the bending element 12α totally reflects the reflected light Lα reflected from the subject 10α by the inclined surface 13α, and converts the path of the reflected light Lα in the positive direction of the Y axis inside the cover portion 24α. The reflected light Lα reflected from the subject 10α that has been totally reflected by the inclined surface 13α is directed to a reflection surface 17α that will be described later. Thus, the inclined surface 13α of the bending element 12α transmits the irradiation light Mα and totally reflects the reflected light Lα. Therefore, a material having a refractive index larger than the refractive index of the space between the cover portion 24α and the substrate portion 26α above the light source 16α is used for the cover portion 24α. For example, a visible light absorption type polycarbonate resin or acrylic resin having a refractive index of about 1.5 is used for the cover portion 24α, and the space may be an air layer. That is, an aluminum reflective film or the like is not deposited on the inclined surface 13α of the bending element 12α in order to totally reflect the reflected light Lα.

The imaging element 14α reflects the reflected light Lα from the subject 10α and forms an image of the subject 10α on the imaging element 15α. The imaging element 14α is located above the image sensor 15α and on the positive side of the Y axis with respect to the image sensor 15α, and is located on a portion of the back surface of the cover part 24α that is not in contact with the substrate part 26α. A recess on the back surface is formed. For example, a toroidal surface having different curvatures in two orthogonal directions is formed on the imaging element 14α. The imaging element 14α reflects the reflected light Lα on the toroidal surface so as to form an image on the imaging element 15α. In order to efficiently reflect the reflected light Lα at the imaging element 14α, for example, a metal reflective film such as aluminum, nickel, gold, silver, or a dielectric dichroic film is deposited on the toroidal surface of the imaging element 14α. .

In the above description, the imaging element 14α is formed with, for example, a toroidal surface. However, the present invention is not limited to this. For example, the imaging element 14α is a reflector such as a spherical surface or an aspherical surface, and is connected to the imaging device 15α. Anything that can be imaged can be used.

The reflection surface 17α causes the reflected light Lα totally reflected by the inclined surface 13α to be incident on the imaging element 14α, and the reflected light Lα reflected from the imaging element 14α is incident on the imaging element 15α. Is reflected. The reflective surface 17α is located above the image sensor 15α and on the upper surface of the cover portion 24α. The reflective surface 17α is formed by depositing a reflective film on the upper surface of the cover portion 24α. Since the reflective film forming the reflective surface 17α is exposed to the outside and can be clearly seen by the user, it is desirable that the reflective film be as inconspicuous as possible in appearance. For example, when the wavelength of light emitted from the light source 16α is an infrared wavelength outside the visible wavelength (for example, 800 nm or more), the reflective film forming the reflecting surface 17α is red in the wavelength band of 800 nm or more emitted from the light source 16α. Any device that reflects external light and transmits light having a visible wavelength band of 800 nm or less may be used. Thus, the reflected light Lα from the subject 10α is efficiently reflected by appropriately setting the wavelength of the light emitted from the light source 16α and the reflectance and transmittance characteristics of the reflecting film forming the reflecting surface 17α. In addition, it is possible to form the reflecting surface 17α that is inconspicuous in appearance.

Further, when the wavelength of light emitted from the light source 16α is an infrared wavelength outside the visible wavelength (for example, 800 nm or more), the material of the cover portion 24α is a visible light absorbing polycarbonate resin or acrylic resin that transmits only infrared light. You can do it. By forming the cover portion 24α with such a material, it is possible to block the visible light component of the unnecessary light entering from the outside of the cover portion 24α with the cover portion 24α. As described above, by forming the reflection surface 17α that reflects infrared light, the infrared light component of the unnecessary light can be blocked by the reflection surface 17α. By blocking unnecessary light incident on the optical pointing device 30α, malfunction due to the unnecessary light can be prevented.

Further, when coloring the surface of the cover unit 24α, which is the surface of the optical pointing device 30α, for example, only the wavelength band of a predetermined color such as green is formed on the upper surface of the cover unit 24α and the upper surface of the reflection surface 17α. May be coated with a material having a characteristic of reflecting other wavelengths and transmitting other wavelengths. By coating the upper surface of the cover portion 24α and the upper surface of the reflection surface 17α with a material having such characteristics, a desired color can be formed on the surface of the optical pointing device 30α without impairing the optical characteristics of the optical pointing device 30α. Can be attached.

The reflection surface 18α reflects the light Lα reflected from the imaging element 14α and reflected by the reflection surface 17α toward the reflection surface 17α again. The reflective surface 18α is located above the image sensor 15α and on the positive side of the Y axis from the image sensor 15α, and is located on the back surface of the cover portion 24α. The reflective surface 18α is formed by depositing a reflective film on the back surface of the cover portion 24α. The reflective film that forms the reflective surface 18α is preferably one that reflects light efficiently. For example, the reflective surface 18α is formed by vapor-depositing a metal such as aluminum, nickel, gold, silver, or a dielectric dichroic film.

Thus, in the optical pointing device 30α of the present embodiment, the cover portion 24α is assembled above the substrate portion 26α with reference to the side surface and the upper surface of the transparent resin 20α of the substrate portion 26α. In the cover portion 24α, contact surfaces 24aα and 24bα serving as a reference for making a decision on the transparent resin 20α of the substrate portion 26α are integrated with the contact surface 11α, the bending element 12α, the imaging element 14α, and the flange 25α. Is formed. Therefore, the contact surfaces 24aα and 24bα, the contact surfaces 11α, the bending element 12α, the imaging element 14α, and the flange 25α are arranged with high precision with mold tolerances. Therefore, the positional relationship with the cover portion 24α can be arranged with high accuracy by bringing the contact surfaces 24aα and 24bα of the cover portion 24α into contact with the side surfaces and the upper surface of the transparent resin 20α of the substrate portion 26α. Therefore, since each unit and each element constituting the optical pointing device 30α can be arranged with high accuracy, the optical pointing device 30α with high detection accuracy of the subject 10α can be realized.

In the optical pointing device 30α configured as described above, a path in which light emitted from the light source 16α is reflected by the subject 10α and enters the image sensor 15α will be described with reference to FIG.

As shown in FIG. 11, first, the irradiation light Mα emitted from the light source 16α is refracted and transmitted by the inclined surface 13α of the bending element 12α and reaches the contact surface 11α. When the subject 10α is on the contact surface 11α, the irradiation light Mα emitted from the light source 16α is scattered and reflected on the surface of the subject 10α that is in contact with the contact surface 11α. The reflected light Lα reflected by the surface of the subject 10α is totally reflected by the inclined surface 13α of the bending element 12α, and the path is changed in the positive direction of the Y axis. The reflected light Lα totally reflected by the inclined surface 13α is reflected by the reflecting surface 17α and reaches the imaging element 14α. Then, the reflected light Lα is reflected back by the imaging element 14α, reflected one after another by the reflecting surface 17α, the reflecting surface 18α, and the reflecting surface 17α, and finally enters the imaging element 15α.

By the way, in the optical pointing device 30α configured as described above, the bending element 12α and the imaging element 14α are integrated in the cover 24α, and the light source 16α and the imaging element 15α are close to each other. There is a possibility that the direct light from the light source 16α may directly enter the image sensor 15α without passing through the imaging element 14α. These incident lights are stray lights, and S / N (Signal / Noise: Signal here) of the image sensor 15α is scattered from a subject incident on the image sensor from the contact surface through the optical path changing means and the imaging reflection section. It is a light component, and “Noise” refers to an unnecessary light component that enters the image sensor through the other optical path) and therefore needs to be removed.

Therefore, in the present embodiment, in order to solve this problem, as shown in FIG. 12, the positive direction of the Y-axis from the end of the total reflection surface of the bending element 12α on the contact surface 24bα side of the cover portion 24α. In addition, a notch portion 19α for stray light countermeasures is formed. The cutout portion 19α will be described in detail below with reference to FIGS. 11, 12, and 13A and 13B. FIG. 12 is a perspective view from the bottom surface 24cα side of the cover portion 24α. 13A is a plan view showing the configuration of the cover portion 24α of the optical pointing device 30α, and FIG. 13B is a cross-sectional view showing the configuration of the cover portion 24α of the optical pointing device 30α.

As shown in FIG. 11, the cutout portion 19α is formed in the cover portion 24α on at least a part on the light source 16α side on the top surface of the image sensor 15α. In addition, the term “at least” indicates that the notch 19α may extend not only to a part on the light source 16α side on the top surface of the image sensor 15α but also to the light source 16α side from the top surface on the image sensor 15α. The main point.

As shown in FIG. 11, the cutout portion 19α is formed in the cover portion 24α from the lowest end of the inclined surface 13α of the bending element 12α to the height of the transparent resin 20α provided with the image sensor 15α. The inclined surface is extended by further forming a notch 19α on the inclined surface that rises to the right.

In FIG. 11, the right inclined surface of the notch 19α is formed on a part of the upper surface of the image sensor 15α. However, the notch 19α has a shape in which the cover 24α is notched so as to avoid the stray light from entering the image sensor 15α, in addition to the slope that rises to the right shoulder or the slope that descends to the right. If it is, it is enough.

Further, the width of the cutout portion 19α in the direction orthogonal to the light guide direction of the cover portion 24α is such that the inclined surface 13α of the bending element 12α made of a prism is shown in FIGS. 12 and 13A and 13B. And the width in the direction orthogonal to the light guide direction of the cover portion 24α in the image sensor 15α. Since the cutout portion 19α is formed in the cover portion 24α, the reflected light from the subject 10α or the light source 16α is prevented from directly entering the imaging device 15α without passing through the imaging device 14α. ing.

The principle that the notched portion 19α can prevent the reflected light from the subject 10α or the direct light from the light source 16α from directly entering the imaging device 15α without passing through the imaging device 14α is shown in FIGS. (A) (b), FIG.16 and FIG.17 demonstrates. FIG. 14 is a cross-sectional view showing the reflected light Lα that is reflected from the subject 10α and is incident on the image sensor 15α after the spread irradiation light Mα emitted from the light source 16α, and FIG. 15A shows a notch 19α. FIG. 15B is a cross-sectional view showing the optical path L1α of the reflected light Lα in the optical pointing device when there is no notch, and FIG. 15B shows the optical path L2α in the other reflected light Lα of the optical pointing device when there is no notch 19α. It is sectional drawing. FIG. 16 is a cross-sectional view showing optical paths M1α and M2α of the irradiation light Mα from the light source 16α to the subject 10α in the optical pointing device without the cutout portion 19α, and FIG. 17 shows the present embodiment. It is sectional drawing which shows the reflected light L (alpha) of the optical pointing device 30 (alpha) provided with the notch part 19 (alpha).

First, as shown in FIG. 14, the irradiation light Mα of the light source 16α is emitted with a certain spread from the light emitting point of the light source 16α. As shown in FIG. 11, a part of the irradiation light Mα is scattered and reflected by the subject 10α, becomes an optical path of the reflected light Lα, and enters the imaging device 15α through the imaging element 14α. However, when the notch 19α is not formed, the other part of the reflected light Lα has an optical path through the imaging element 14α as shown in FIGS. 15 (a) and 15 (b). The light does not pass and becomes stray light such as the optical path L1α and the optical path L2α, and enters the image sensor 15α.

In addition, as shown in FIG. 16, stray light such as an optical path M1α and an optical path M2α that are not directed to the subject 10α in the irradiation light Mα of the light source 16α may be directly incident on the image sensor 15α.

In the cover part 24α, the light guided inside is normally totally reflected inside and therefore does not come out from the cover part 24α. However, the light paths L1α and L2α that do not pass through the optical path through the imaging element 14α described above, etc. The stray light such as the optical path M1α and the optical path M2α due to the stray light or the direct light not directed to the subject 10α has an acute emission angle or an adhesive or transparent resin 20α and a cover having a refractive index that approximates the refractive index of the cover portion 24α. Since it is in contact with the portion 24α, the light is emitted to the outside of the cover portion 24α.

In these cases, the signal component obtained by image processing of the image picked up on the image pickup device 15α by the light passing through the imaging element 14α of the reflected light Lα by the circuit board 21α is the amount and direction of movement when the subject 10α is moved. In contrast, the same information by the light passing through the optical paths L1α and L2α or the optical paths M1α and M2α can be obtained only when the subject 10α moves. For this reason, not only the signal information cannot be obtained, but also the non-moving image overlaps the moving image, thereby hiding the movement of the image, so that accurate signal information cannot be obtained. In the following description, the reflected light Lα that passes through the imaging element 14α from which signal information is obtained is referred to as signal light, and the light other than the signal light is referred to as noise light.

On the other hand, when the cutout portion 19α is formed in the cover portion 24α, as shown in FIG. 17, for example, the optical paths M1α and M2α that are direct light from the light source 16α are reflected by the cutout portion 19α. Thus, the light does not directly enter the image sensor 15α. Therefore, it is possible to prevent direct light from the light source 16α and stray light such as the optical paths L1α and L2α from directly entering the image sensor 15α without passing through the imaging element 14α. Further, the notch 19α is also effective for disturbance light from the outside of the optical pointing device 30α.

In the optical pointing device 30α having the cover portion 24α in which the contact surface 11α, the bending element 12α, and the imaging element 14α are integrally formed, the cutout portion 19α is formed in the cover portion 24α. It is possible to prevent stray light such as reflected light from the subject 10α or direct light from the light source 16α from directly entering the image sensor 15α without passing through the imaging element 14α. Is reflected by the imaging element 14α and is incident from the back side of the image sensor 15α, whereas stray light such as reflected light from the subject 10α or direct light from the light source 16α is generated on the front side of the image sensor 15α. This is due to incidence from a certain light source 16α side. In other words, the incident direction of the signal light and the incident direction of the stray light with respect to the imaging element 15α are opposite to each other.

Further, in the present embodiment, the formation range of the cutout portion 19α is a range that does not inhibit the reflected light Lα that is effective as signal light in the reflected light Lα from the subject 10α.

Here, in the present embodiment, not only the notch portion 19α is formed in the cover portion 24α, but also a light shielding film 19aα can be further provided in the notch portion 19α as shown in FIG. 18, for example. By the light shielding film 19aα, the stray light component relating to the optical path L1α / L2α or the optical path M1α / M2α can be shielded, and the stray light countermeasure effect can be enhanced. The light shielding film 19aα can be formed by, for example, black paint or ink mixed with carbon black by inkjet, printing, or vapor deposition. Such a black film is preferable because it absorbs light.

Here, for example, when there is a total reflection surface in the immediate vicinity of a place where countermeasures against stray light are to be applied, stray light from a small portion that is not covered becomes a problem even if most of the surface is covered with the light shielding film 19aα. This is because the formation accuracy of the light shielding film 19aα is as low as 0.5 mm to 1 m, and it is necessary to enlarge the mask so that the light shielding film 19aα is not attached to the total reflection surface. Since the manufacturing accuracy is one digit or more (about 10 μm) from the above value, it is sufficiently possible to form the notch 19α in a portion where the light shielding film 19aα cannot be formed.

The effect of the notch 19α will be described with reference to FIGS. 19 (a), 19 (b), 19 (c) and 19 (d). FIG. 19A is a distribution diagram showing the illuminance distribution in the image sensor 15α when the cover 24α does not have the notch 19α, and FIG. 19B shows only the notch 19α in the cover 24α. FIG. 19C is a distribution diagram showing the illuminance distribution in the image sensor 15α when the image sensor 15α is used, and FIG. FIG. 19D is a graph in which (a), (b), and (c) of FIG. 19 are collectively represented as one. In addition, each graph of (a), (b), (c), and (d) in FIG. 19 is expressed by standardizing the peak value of the illuminance distribution when there is no notch 19α as 1.

When the cover portion 24α does not have the cutout portion 19α, strong stray light is seen at the left end as shown in FIGS. 19 (a) and 19 (d). On the other hand, when only the cutout portion 19α exists in the cover portion 24α, it can be seen that the stray light is reduced as a whole as shown in FIGS. The ratio of the stray light detected by the image sensor 15α when the case where there is no notch 19α at this time is 1 is 0.65 according to the calculation. Further, when the cutout portion 19α is formed in the cover portion 24α and the light shielding film 19aα is further applied, strong stray light at the left end is eliminated as shown in FIGS. 19 (c) and 19 (d). I understand. The ratio of the stray light detected by the image sensor 15α when the case where there is no notch 19α at this time is 1 is 0.17 according to the calculation.

As described above, in the present embodiment, by forming the notch portion 19α and the light shielding film 19aα in the cover portion 24α, it is possible to improve the imaging characteristics particularly in improving the contrast of the image and improve the characteristics of the optical pointing device 30α. It was also found that improvement in yield can be expected.

Note that the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention. For example, in the above embodiment, the surface of the transparent resin 20α is transparent, but it is also possible to prevent light shielding.

Specifically, for example, a light-shielding resin may be resin-sealed on the side surface of the transparent resin 20α and on the upper surface of the transparent resin 20α excluding a portion where the reflected light Lα from the subject 10α is transmitted. As the light-shielding resin, for example, a thermosetting resin such as a silicone resin or an epoxy resin, or a thermoplastic resin such as acrylic or polycarbonate can be used in the same manner as the light-transmitting resin. However, unlike the light-transmitting resin, the light-blocking resin includes carbon black. In this way, by sealing the light-shielding resin around the transparent resin 20α, the light emitted from the light source 16α is reflected directly or at a place other than the subject 10α and enters the image sensor 15α. Can be prevented. It is possible to prevent so-called stray light that is not reflected light Lα from the subject 10α from entering the image sensor 15α. Therefore, malfunction of the optical pointing device 30α due to stray light can be prevented, and the subject 10α can be detected with high accuracy.

As described above, the optical pointing device 30α of the present embodiment includes the light source 16α that irradiates the subject 10α with light and the cover as a light guide type optical member that reflects and guides the reflected light from the subject 10α. Part 24α and an image sensor 15α that receives the light guided by the cover part 24α. The cover 24α has a contact surface 11α that contacts the subject 10α, an imaging element 14α that serves as an imaging reflection unit that guides the guided light to the imaging device 15α, and the direction of reflected light from the subject 10α. A bending element 12α is integrally formed as an optical path changing means that converts the light into the imaging element 14α. Therefore, by adopting such a cover portion 24α, the length of the cover portion 24α in the vertical direction can be made smaller than the optical path length even if the optical path length of the optical system is increased and aberrations are suppressed. And miniaturization can be achieved. Further, by integrally forming the contact surface 11α, the bending element 12α, and the imaging element 14α, the number of parts can be reduced and the number of assembly steps can be reduced. In addition, by forming a mold for forming the cover portion 24α with high accuracy, the inclined surface 13α and the imaging element 14α of the bending element 12α can be manufactured with high accuracy, and the contact surface 11α, the bending element 12α, The positional relationship of the image element 14α can also be arranged with mold accuracy. Therefore, the manufacturing cost of the optical pointing device 30α can be reduced, and the optical pointing device 30α with high detection accuracy of the subject 10α can be realized.

Further, when the contact surface 11α, the bending element 12α, and the imaging element 14α are assembled as separate parts, shapes such as an abutting surface for assembly and a fitting shape are required. Furthermore, as a measure against stray light, the cutout portion 19α cannot be formed, so a separate member such as a light shielding sheet or stray light prevention means is required, and the shape of the contact surface, fitting shape, etc. for assembling them is also required. In addition, it is necessary to secure a margin for adjusting the relative positional relationship between them.

On the other hand, when integrated, the above-described fitting shape is not necessary, and if there is a minimum optical surface, it is not necessary to secure an adjustment margin, and the contact surface 11α, the bending element 12α, and the imaging element are not required. The thickness of the cover portion 24α including the child 14α can be reduced. Therefore, the thickness of the optical pointing device 30α can be reduced.

However, in the cover portion 24α in which the contact surface 11α, the bending element 12α, and the imaging element 14α are integrally formed, stray light such as reflected light from the subject 10α or direct light from the light source 16α does not pass through the imaging element 14α. May be directly incident on the image sensor 15α, and such stray light reduces the S / N of the image sensor 15α.

Therefore, in the present embodiment, the cover portion 24α has a cutout portion that prevents the reflected light from the subject 10α or the direct light from the light source 16α from directly entering the imaging device 15α without passing through the imaging device 14α. 19α is formed on at least a part on the light source 16α side on the top surface of the image sensor 15α. For this reason, the notched portion 19α is formed at least in part on the light source 16α side on the top surface of the image pickup device 15α, so that the reflected light from the subject 10α or the direct light from the light source 16α does not pass through the imaging device 14α. When the stray light consisting of is emitted from the inside of the cover part 24α, it is reflected by the notch part 19α, the incident angle changes, and it can be prevented from being emitted from the inside of the cover part 24α. As a result, it is possible to prevent stray light including reflected light from the subject 10α not passing through the imaging element 14α or direct light from the light source 16α from directly entering the imaging element 15α.

Further, in the present embodiment, in order to prevent stray light, only the cutout portion 19α is formed in the cover portion 24α. Therefore, stray light incident on the image sensor 15α can be suppressed with a simple configuration without using a special light shielding wall or light shielding member.

Therefore, when using the cover portion 24α in which the bending element 12α and the imaging element 14α are integrated, it is possible to easily reduce the influence of stray light and provide the optical pointing device 30α with high detection accuracy of the subject 10α. it can.

Further, in the optical pointing device 30α of the present embodiment, the reflected light from the subject 10α or the direct light from the light source 16α is directly incident on the imaging element 15α without passing through the imaging element 14α. It is preferable to provide a light-shielding film 19aα as a light-shielding member for preventing the above.

Thereby, stray light composed of reflected light from the subject 10α not passing through the imaging element 14α or direct light from the light source 16α is shielded by the light shielding film 19aα when emitted from the inside of the cover portion 24α. Accordingly, it is possible to reliably prevent stray light including reflected light from the subject 10α not passing through the imaging element 14α or direct light from the light source from directly entering the imaging element 15α.

Further, in the optical pointing device 30α of the present embodiment, it is preferable that the light shielding member is made of a black film.

As a result, since the black film has a property of absorbing light, stray light including reflected light from the subject 10α reflected by the cutout portion 19α or direct light from the light source is generated inside the cover portion 24α. It is possible to prevent the light from being reflected by the light source and reflected by the imaging reflection part and finally entering the image sensor. Therefore, it is possible to reliably reduce the influence of stray light and provide the optical pointing device 30α with high detection accuracy of the subject 10α.

Also, in the optical pointing device 30α of the present embodiment, the optical path changing means can be made of a prism that is a bending element 12α that refracts reflected light from the subject 10α.

Thereby, by using a general prism as the optical path changing means, the optical path changing means can be easily configured. In addition, since the prism totally reflects incident light, the light use efficiency is highest with respect to optical path deflecting means such as a reflective diffractive element, a reflective Fresnel lens, or a reflective hologram lens. As a result, the image projected onto the image sensor 15α becomes brighter, and the S / N ratio can be improved.

Further, in the optical pointing device 30α of the present embodiment, the imaging element 14α is configured by any one of a spherical surface, an aspherical surface, and a toroidal surface. Accordingly, the curvature of the imaging element 14α is changed to a spherical surface based on the optical aberration such as spherical aberration and coma generated from the configuration of the optical system of the optical pointing device 30α, and the distortion amount of the image projected on the imaging element 15α. The optical characteristics of the cover 24α of the optical pointing device 30α can be further improved by appropriately setting the aspherical surface or the toroidal surface.

[Sixth Embodiment]
A sixth embodiment of the present invention will be described with reference to FIGS. FIG. 20 is a schematic sectional view showing an optical pointing device 40α according to the sixth embodiment. In the sixth embodiment, a diffractive element 42α is arranged instead of the bending element 12α that totally reflects the reflected light Lα in the horizontal direction in the fifth embodiment. Hereinafter, differences from the fifth embodiment due to the arrangement of the diffraction element 42α in the sixth embodiment will be described. In the sixth embodiment, the description of the same configuration as that of the fifth embodiment is omitted.

As shown in FIG. 20, the optical pointing device 40α of the present embodiment includes a diffractive element 42α as an optical path deflecting unit instead of the bending element 12α of the fifth embodiment that totally reflects the reflected light Lα in the horizontal direction. It is arranged. Therefore, the inclined surface 13α of the bending element 12α does not exist in the cover portion 24α.

The cover portion 24α includes a contact surface 11α, a diffraction element 42α, an imaging element 14α, a notch portion 19α, and reflection surfaces 17α and 18α. The cover portion 24α is located on the upper side of the substrate portion 26α, on both side surfaces of the circuit board 21α, the negative side surface of the Y axis in the transparent resin 20α, and the positive side surface and the upper surface of the transparent resin 20α. It is in close contact.

The diffractive element 42α is located above the light source 16α and below the contact surface 11α, and at a portion of the contact surface 24bα on the back surface of the cover portion 24α that does not contact the substrate portion 26α. The diffractive element 42α reflects the reflected light Lα reflected from the subject 10α, and converts the path of the reflected light Lα in the positive direction of the Y axis inside the cover 24α. The reflected light Lα reflected from the subject 10α reflected by the diffraction element 42α travels toward the reflecting surface 17α.

A specific configuration of the diffraction element 42α will be described with reference to FIGS. FIG. 21A is a schematic configuration diagram showing a cross-sectional shape of the diffraction element 42α.

A diffraction element 42α shown in FIG. 21 (a) is a reflection type diffraction element using + 1st order reflected diffraction light. In the diffractive element 42α composed of the reflective diffractive element, as shown in FIG. 21A, in order to improve the reflectance, the outer surface of the diffractive element 42α (the surface on the negative side of the Z axis), for example, It is desirable to deposit a reflective film 42aα such as aluminum, silver, gold, or a dielectric dichroic film.

Further, the shape of the diffraction element 42α made of a reflection type diffraction element is desirably a blazed shape, for example, as shown in FIG. 21A so that + 1st order light is strongly generated. By using the blazed diffraction element 42α shown in FIG. 21A, the light utilization efficiency can be improved and the 0th-order light, the −1st-order light, and the higher-order diffracted light that become stray light can be suppressed. Therefore, in the optical pointing device 40α, it is possible to prevent the imaging performance of the optical system from deteriorating.

Here, as shown in FIG. 21A, assuming that the blazed groove depth (length in the Z direction) of the diffractive element 42α is tα, the groove depth tα has the maximum + 1st order diffraction efficiency. Depth is desirable. For example, when the refractive index nα of the cover 24α and the wavelength of light emitted from the light source 16α are λα, it is desirable that tα = λα / (2nα).

Further, the blazed groove pattern of the diffractive element 42α is a groove pattern with straight lines of equal pitch as shown in FIG. 21B, and it is desirable to make it as fine as possible in order to make the diffraction angle as large as possible. . However, in terms of manufacturing, it is most advantageous in terms of cost to form and mold the groove by cutting using a cutting tool for the mold. Therefore, in consideration of the range in which the grooves can be accurately manufactured by cutting, it is desirable to design the groove pitch of the diffraction element 42α between 0.8 and 3.0 μm.

Furthermore, in order to improve the imaging performance for capturing the image of the subject 10α projected onto the image sensor 15α, as shown in FIG. Distortion can be corrected. Further, as shown in FIG. 21 (d), the diffraction element 42α is designed so that the groove pitch of the diffraction element 42α is not an equal pitch but a pattern in which the pitch gradually changes, and has a lens effect in a certain direction. May be. In this case, on the image sensor 15α, it is possible to correct an aberration that occurs due to a difference in focal length between the X-axis direction and the Y-axis direction.

Further, as shown in FIG. 21E, both the distortion of the image and the astigmatism (astigmatism) can be corrected by making the groove pattern of the diffraction element 42α a curved and unequal pitch pattern. .

Next, as another specific example of the diffraction element 42α, a reflection type Fresnel lens may be used as the diffraction element 42α. A specific shape of the reflective Fresnel lens is shown in FIG. FIG. 22 is a schematic configuration diagram showing a cross-sectional shape of a reflective Fresnel lens.

As shown in FIG. 22, the cross-sectional shape of the reflective Fresnel lens is a blazed shape. When a reflective Fresnel lens is used as the diffractive element 42α, the thickness of the cover 24α can be made uniform as compared with the case where a prism or a bulk lens is formed on a part of the cover 24α. Therefore, it is possible to reduce the thickness of the optical pointing device 40α while increasing the strength of the cover portion 24α. Also in the reflection type Fresnel lens, in order to improve the reflectance, a reflection film 42aα such as aluminum, silver, gold, a dielectric dichroic film, etc. is formed on the outer surface (surface on the negative side of the Z axis) of the diffraction element 42α. It is desirable to vapor-deposit.

It is also possible to use a reflection hologram lens as the diffraction element 42α. If a reflection hologram lens is used as the diffractive element 42α, it is possible to correct aberrations that cannot be corrected by a normal lens, so that the imaging performance is improved and the image of the subject 10α can be clearly projected on the image pickup element 15α. it can.

As described above, when the diffractive element 42α is used to reflect the reflected light Lα reflected from the subject 10α in the horizontal direction, the cover portion 24α can be compared with the case where the bending element 12α made of a prism is formed on the cover portion 24α. The thickness can be made uniform. Therefore, it is possible to reduce the thickness while increasing the strength of the cover portion 24α. In addition, the light irradiated from the light source 16α can be irradiated to the contact surface 11α with a uniform light intensity.

Further, in the optical pointing device that bends the reflected light Lα from the subject 10α in the horizontal direction (for example, the configuration of Patent Documents 3 and 4 which are conventional techniques), the size of the bending element 12α, particularly the length in the Z-axis direction. Greatly affects the thickness of the optical pointing device. That is, in order to design the optical pointing device thin, it is important to reduce the length of the bending element 12α in the Z-axis direction. However, the size of the bending element 12α cannot be designed freely, and the size of the bending element 12α depends on the size of the contact surface 11α. In order to detect a pattern on the contact surface 11α, the contact surface 11α must have a certain area. As a result, if the area of the contact surface 11α is to be secured, the bending element 12α is inevitably increased, and the thickness (size in the Z-axis direction) of the optical pointing device cannot be reduced.

In the present embodiment, the optical pointing device 40α is made thinner than in the fifth embodiment by using the diffraction element 42α that can be smaller in length in the Z-axis direction than the bending element 12α. Can be planned.

Also in the present embodiment, similarly to the fifth embodiment, the contact surfaces 24aα and 24bα cover the substrate portion 26α above the substrate portion 26α on the basis of the positive side surface and the upper surface of the transparent resin 20α. The part 24α is assembled. Therefore, the positional relationship between the substrate portion 26α and the cover portion 24α can be arranged with high accuracy. Therefore, since each part and each element constituting the optical pointing device 40α can be arranged with high accuracy, the optical pointing device 40α with high detection accuracy of the subject 10α can be realized.

As described above, in the optical pointing device 40α according to the present embodiment, the optical path conversion means includes the diffraction element 42α as the optical path deflection means that deflects the direction of the reflected light from the subject 10α and guides it to the imaging element 14α. At the same time, the diffractive element 42α is configured by any one of a reflective diffractive element, a reflective Fresnel lens, and a reflective hologram lens.

As a result, the light path conversion means composed of the diffraction element 42α is less efficient in using light than the light path conversion means based on total reflection such as a prism. However, when the diffractive element 42α is formed on the side opposite to the contact surface 11α of the cover part 24α, the cover part 24α including the function of the diffractive element 42α can be formed without forming a concave portion therefor. . As a result, it is not necessary to form the concave portion as compared with the optical path changing means by total reflection such as a prism in which the concave portion is formed, so that the thickness of the cover portion 24α can be made thin and uniform.

Therefore, it is possible to reduce the thickness of the cover portion 24α, and thus to realize a thin optical pointing device 30α.

In addition, when the diffraction element 42α is a reflection hologram lens, it can have a role of correcting aberrations that cannot be corrected by the imaging element 14α. As a result, the imaging performance of the imaging element 14α is improved, and the image of the subject 10α can be clearly captured by the imaging element 15α. Therefore, the performance of the optical pointing device 40α can be improved.

[Seventh Embodiment]
A seventh embodiment of the present invention will be described with reference to FIG. FIG. 23 is a schematic cross-sectional structure diagram showing the configuration of the optical pointing device 50α in the seventh embodiment. In the seventh embodiment, the same configuration as that of the fifth embodiment will be described for the sake of explanation. However, the changed portion and the effect are the same as those of the sixth embodiment, and the same effect is obtained. The description of the same parts as those of the fifth embodiment is omitted.

In the seventh embodiment, in addition to the configurations of the fifth and sixth embodiments, shielding films 51aα and 51bα that shield light from the outside of the device are formed on the contact surface 11α of the cover portion 24α. Is different.

As shown in FIG. 23, the optical pointing device 50α of the present embodiment is a shield that blocks light from the outside of the device on the contact surface 11α of the cover portion 24α of the optical pointing device 30α shown in the fifth embodiment. Films 51aα and 51bα are formed. Note that the window area indicated by Pα in the figure is a portion where the shielding films 51aα and 51bα are not formed and the subject 10α is in contact with the contact surface 11α of the cover 24α, and the light from the light source 16α is the shielding film 51aα. An area that can reach the subject 10α without being blocked by 51bα.

In the optical pointing device 50α according to the present embodiment, the light from the outside of the optical pointing device 50α is emitted from a portion other than the object surface on the cover contact surface that provides good characteristics in the imaging element 14α. Since the image is internally reflected and incident on the image sensor 15α, the contrast of the image captured by the image sensor 15α becomes disturbance light with respect to the signal light passing through the optical system including the imaging element 14α of the cover 24α. Decreases. Of course, even when the subject 10α is a finger even when the light comes from outside the apparatus, the light transmitted through the finger enters the cover portion 24α from the contact surface and passes through the optical system including the imaging element 14α. However, since the amount of disturbance light is larger, the contrast of the image is lowered as a result.

However, according to the above configuration, since the influence of the disturbance light can be suppressed and only the signal light can be enhanced, the contrast of an image photographed by the imaging element is improved.

The shielding films 51aα and 51bα may be reflective films such as aluminum, silver, gold, and dielectric dichroic films that specifically reflect disturbance light, and may also absorb disturbance light in situ, such as carbon black. It may be an absorption film such as paint or black ink. In the case of a vapor deposition film, vapor deposition may be performed by masking the window area, and in the case of an absorption film, it may be formed by ink jet or pad printing.

The area where the shielding films 51aα and 51bα are formed is only required to be formed in the positive direction of the Z axis with respect to the flange 25α protruding from the housing of the device because the flange 25α is disposed inside the housing of the device to be mounted. . In addition, since the casing of the device has a thickness and disturbance light is shielded by the thickness, the shielding film 51bα is not always necessary, and measures such as forming only the shielding film 51aα may be appropriately performed.

In the present embodiment, FIG. 23 shows that the shielding films 51aα and 51bα are formed on the contact surface 11α of the cover portion 24α in the optical pointing device 30α shown in the fifth embodiment. However, the present invention is not necessarily limited to this, and the shielding films 51aα and 51bα can be formed on the optical pointing device 40α of the sixth embodiment, and the effect thereof is the same as that of the present embodiment.

Thus, in the optical pointing device 50α of the present embodiment, at least the shielding film 51aα that shields light from the outside is provided in the surface region other than the contact surface 11α with which the subject 10α contacts in the cover 24α. Yes.

That is, in the light coming from the outside of the optical pointing device 50α, the light from other than the subject 10α on the contact surface 11α that provides good characteristics in the imaging element 14α becomes disturbance light for the optical pointing device 50α.

However, in the present embodiment, the surface region other than the contact surface 11α is provided with the shielding film 51aα that blocks light from the outside, so that the influence of disturbance light can be suppressed. Therefore, it is possible to improve the contrast of an image photographed by the image sensor 15α.

[Eighth Embodiment]
Finally, an electronic device equipped with the optical pointing device 30α / 40α / 50α of the present embodiment will be described with reference to FIG. FIG. 24 is a diagram showing an appearance of a mobile phone 60α as an electronic device equipped with any one of the optical pointing devices 30α, 40α, and 50α. 24A is a front view of the mobile phone 60α, FIG. 24B is a rear view of the mobile phone 60α, and FIG. 24C is a side view of the mobile phone 60α. In FIGS. 24A, 24B and 24C, an example is shown in which the cellular phone 60α is used as the electronic device, but the present invention is not limited to this. The electronic device may be, for example, a PC (particularly a mobile PC), a PDA (Personal Digital Assistant: personal digital assistant), a game machine, a remote controller such as a television, or the like.

As shown in FIG. 24, the cellular phone 60α includes a monitor-side casing 61α and an operation-side casing 62α. The monitor-side casing 61α includes a monitor unit 65α and a speaker unit 66α, and the operation-side casing 62α includes a microphone unit 63α, a numeric keypad 64α, and, for example, an optical pointing device 30α. The optical pointing device 30α mounted on the mobile phone 60α is not necessarily limited to this, and any of the optical pointing devices 40α and 50α can be applied.

In the present embodiment, the optical pointing device 30α is arranged on the upper part of the numeric keypad 64α as shown in FIG. 24A. However, the arrangement method and the direction of the optical pointing device 30α will be described below. It is not limited.

The speaker unit 66α outputs audio information to the outside, and the microphone unit 63α inputs audio information to the mobile phone 60α. The monitor unit 65α outputs video information. In the present embodiment, the monitor unit 65α displays input information from the optical pointing device 30α.

Note that, as shown in FIGS. 24A to 24C, the cellular phone 60α of the present embodiment includes an upper casing (monitor side casing 61α) and a lower casing (operation side casing 62α). As an example, a so-called foldable mobile phone 60α is connected to each other via a hinge. Since the folding type is mainly used as the cellular phone 60α, a folding type cellular phone is given as an example in this embodiment, and the cellular phone 60α on which the optical pointing device 30α can be mounted is a folding type. It is not limited to.

In recent years, a folding mobile phone 60α having a thickness of 10 mm or less in a folded state has also appeared. If the portability of the mobile phone 60α is taken into consideration, its thickness is an extremely important factor. In the operation side casing 62α shown in FIGS. 24A, 24B, and 24C, the components that determine the thickness of the operation side casing 62α except for an internal circuit board (not shown) are a microphone unit 63α, a numeric keypad 64α, and an optical pointing device. 30α. Among these, the thickness of the optical pointing device 107α is the largest, and the thinning of the optical pointing device 30α directly leads to the thinning of the mobile phone 60α. Therefore, the optical pointing device of the present invention that can be thinned as described above is a preferred invention for an electronic device that needs to be thinned, such as the cellular phone 60α.

As described above, the cellular phone 60α as the electronic apparatus of the present embodiment includes the optical pointing devices 30α, 40α, and 50α. Therefore, when using the cover 24α in which the optical path changing unit and the imaging reflection unit are integrated, it is possible to provide the mobile phone 60α including the optical pointing devices 30α, 40α, and 50α that are less affected by stray light.

In each of the fifth to eighth embodiments, when a light guide type optical member in which an optical path changing unit and an imaging reflection unit are integrated is used, the influence of stray light can be easily reduced and the detection accuracy of a subject can be improved. A high optical pointing device and an electronic device including the same are provided. The cover 24α has a contact surface 11α with which the subject 10α comes into contact, an imaging element 14α that guides the guided light to the image sensor 15α, and a direction of reflected light from the subject 10α to change the direction of the reflected light to the imaging element 14α. A bending element 12α such as a guiding prism is integrally formed. The imaging element 15α is disposed on the lower side of the light source 16α with respect to the imaging element 14α in the cover portion 24α. The cover 24α further includes a notch 19α that prevents the reflected light from the subject 10α or the direct light from the light source 16α from directly entering the image sensor 15α without passing through the imaging element 14α. It is formed on at least part of the light source 16α side on the top surface.

[Ninth Embodiment]
A ninth embodiment of the present invention will be described with reference to FIGS. FIG. 27A is a schematic cross-sectional view showing an optical pointing device 30β in the ninth embodiment, and FIG. 27B is a perspective view showing a configuration of a cover portion of the optical pointing device.

The optical pointing device 30β of the present embodiment includes a substrate portion 26β and a cover portion 24β that is a light guide type optical member, as shown in FIG. The board portion 26β is composed of a circuit board 21β, a light source 16β, an image sensor 15β, and a transparent resin 20β. The cover portion 24β includes a contact surface 11β, an optical path changing means for forming the inclined surface 13β, a bending element 12β as a prism, an imaging reflecting mirror 14β as an imaging element, and reflecting surfaces 17β and 18β. The subject 10β that is in contact with the contact surface 11β of the cover 24β is a subject such as a fingertip, and is an object for which the optical pointing device 30β detects the movement of the finger fingerprint. Here, in order to make it easy to understand the state of the subject 10β with respect to the optical pointing device 30β, the subject 10β is described small for convenience with respect to the optical pointing device 30β.

Here, the thickness direction of the optical pointing device 30β (vertical direction in FIG. 27A) is taken as the Z axis, and the width direction of the optical pointing device 30β (lateral direction in FIG. 27A) is taken as the Y axis. . The direction from the lower part to the upper part of the optical pointing device 30β is defined as the positive direction of the Z axis, and the direction from the light source 16β toward the image sensor 15β is defined as the positive direction of the Y axis. The positive direction of the Z axis is also called the vertical direction, and the positive direction of the Y axis is also called the horizontal direction. Although not shown, the depth direction of the optical pointing device 30β is taken as the X axis, and the direction from the back side to the near side of the optical pointing device 30β shown in FIG. 27 is taken as the positive direction of the X axis.

First, the configuration of the substrate part 26β will be described.

In the board portion 26β of the present embodiment, the light source 16β and the image sensor 15β are mounted on one circuit board 21β. The light source 16β and the image sensor 15β are electrically connected to the circuit board 21β by wire bonding or flip chip mounting. A circuit is formed on the circuit board 21β. The circuit controls the light emission timing of the light source 16β or detects the movement of the subject 10β by receiving an electrical signal output from the image sensor 15β. The circuit board 21β has a planar shape made of the same material, and is made of, for example, a printed board or a lead frame.

The light source 16β emits light toward the contact surface 11β of the cover portion 24β. The irradiation light Mβ emitted from the light source 16β is refracted by the bending element 12β of the cover portion 24β through the transparent resin 20β, the traveling direction is changed, and reaches the contact surface 11β. That is, the irradiation light Mβ is incident on the contact surface 11β from an oblique direction, that is, at a certain incident angle with respect to the contact surface.

As will be described later, since the cover portion 24β is made of a material having a refractive index larger than that of air, a part of the irradiation light Mβ that has reached the contact surface 11β is a contact surface when there is no subject 10β on the contact surface 11β. 11β is transmitted, and the remaining part is reflected by the contact surface 11β. At this time, when the incident angle of the irradiation light Mβ with respect to the contact surface 11β satisfies the condition of total reflection, the irradiation light Mβ does not pass through the contact surface 11β but is reflected by the contact surface 11β and goes into the cover portion 24β.

On the other hand, when the subject 10β is on the contact surface 11β, the irradiation light Mβ is reflected by the surface of the subject 10β in contact with the contact surface 11β and is incident on the cover portion 24β. The light source 16β is realized by a light source such as an LED, for example, and is preferably realized by an infrared light emitting diode with high luminance.

The imaging element 15β receives the scattered reflected light Lβ reflected by the subject 10β irradiated by the light source 16β, forms an image on the contact surface 11β based on the received light, and converts it into image data. . Specifically, the image sensor 15β is composed of an image sensor such as a CMOS or a CCD. The image sensor 15β includes a DSP (not shown), and takes the received irradiation light Mβ into the DSP as image data. The imaging element 15β continues to capture images on the contact surface 11β at regular intervals in accordance with instructions from the circuit board 21β.

When the subject 10β in contact with the contact surface 11β moves, the image captured by the image sensor 15β is different from the image captured immediately before. In the DSP, the image sensor 15β compares the values of the same portion of the captured image data with the immediately preceding image data, and calculates the movement amount and movement direction of the subject 10β. That is, when the subject 10β moves on the contact surface 11β, the captured image data is image data indicating a value deviated from the image data captured immediately before by a predetermined amount. In the DSP, the imaging element 15β calculates the movement amount and movement direction of the subject 10β based on the predetermined amount. The imaging element 15β outputs the calculated movement amount and movement direction to the circuit board 21β as electric signals. Note that the DSP may be included in the circuit board 21β instead of in the image sensor 15β. In that case, the imaging element 15β transmits the captured image data to the circuit board 21β in order.

Summarizing the processing of the image sensor 15β, the image sensor 15β captures an image of the contact surface 11β when there is no subject 10β on the contact surface 11β. Next, when the subject 10β comes into contact with the contact surface 11β, the imaging element 15β captures an image of the surface of the subject 10β in contact with the contact surface 11β. For example, when the subject 10β is a fingertip, the imaging element 15β captures an image of a fingertip fingerprint. Here, since the image data captured by the image sensor 15β is different from the image data when the subject 10β is not present on the contact surface 11β, the DSP of the image sensor 15β is subject to the subject 10β on the contact surface 11β. Is transmitted to the circuit board 21β. When the subject 10β moves, the movement amount and movement direction of the subject 10β are calculated compared with the image data captured immediately before by the DSP, and a signal indicating the calculated movement amount and movement direction is transmitted to the circuit board 21β. .

The light source 16β and the image sensor 15β are sealed with a transparent resin 20β, which is a translucent resin. The shape of the transparent resin 20β is a substantially rectangular parallelepiped. The bottom surface of the transparent resin 20β is in close contact with and in contact with the upper surface of the circuit board 21β, and concave portions that are in close contact with the light source 16β and the imaging element 15β are formed. As the translucent resin constituting the transparent resin 20β, for example, a thermosetting resin such as a silicone resin or an epoxy resin, or a thermoplastic resin such as acrylic or polycarbonate is used.

Thus, since the light source 16β and the image sensor 15β mounted on the circuit board 21β are respectively sealed with the transparent resin 20β, the circuit board 21β, the light source 16β, the image sensor 15β, and the transparent resin 20β are integrated. A substrate portion 26β is formed. Therefore, the number of parts of the optical pointing device 30β can be reduced, and the number of assembly steps can also be reduced. Therefore, the manufacturing cost of the optical pointing device 30β can be reduced, and the optical pointing device 30β with high detection accuracy of the subject 10β can be realized.

Next, the configuration of the cover part 24β will be described.

The cover part 24β protects each part and each element constituting the optical pointing device 30β such as the light source 16β and the imaging element 15β. The cover portion 24β is positioned above the substrate portion 26β and is in close contact with and in contact with the side surface and the upper surface of the substrate portion 26β. That is, some of the contact surfaces 24aβ and 24bβ on the back surface of the cover portion 24β are in close contact with and in contact with the side surface and the upper surface of the substrate portion 26β. In the present embodiment, the surface of the cover portion 24β on the negative side of the Z-axis that is not exposed to the outside when mounted on the substrate portion 26β and formed as the optical pointing device 30β. This is referred to as the back surface of the cover portion 24β.

Also, the bottom surface 24cβ of the cover portion 24β forms the same plane as the bottom surface 26aβ of the substrate portion 26β. Further, the upper surface of the cover portion 24β, the contact surface 24bβ of the cover portion 24β, the bottom surface 26aβ of the substrate portion 26β and the bottom surface 24cβ of the cover portion 24β are parallel to each other, and both side surfaces of the cover portion 24β are covered. The upper surface of the portion 24β, the contact surface 24bβ of the cover portion 24β, the bottom surface 26aβ of the substrate portion 26β, and the surface having an angle with respect to the bottom surface 24cβ of the cover portion 24β are formed. That is, as shown in FIG. 27, in the cross-sectional view of the optical pointing device 30β, the cover portion 24β has a trapezoidal shape. However, the cover portion 24β is not limited to this shape, and the side surface may be perpendicular to the bottom surface 24cβ.

The front and rear side flanges 25β and the side surface side flanges 27β are provided in the front and rear sides of the cover portion 24β and near the bottoms of the side surfaces. The front and rear flanges 25β and the side flanges 27β are mounted on the electronic device with the optical pointing device 30β of the present embodiment, and are pushed from the contact surface 11β of the cover portion 24β toward the negative direction of the Z axis by the subject 10β such as a finger. In this case, the force generated in the positive direction of the Z-axis by a leaf spring contact switch (not shown) provided on the bottom surface 26aβ of the base plate portion 26β is regulated at a certain position, and a certain stroke amount required as a pushbutton switch Used to ensure.

The contact surface 11β in the cover part 24β is a surface where the subject 10β contacts the optical pointing device 30β. The contact surface 11β is located above the light source 16β on the upper surface of the cover portion 24β.

The bending element 12β is a prism, and is located above the light source 16β and below the contact surface 11β, and is located on the back surface of the cover portion 24β at a portion not in contact with the substrate portion 26β. Are formed. The bending element 12β has an inclined surface 13β, and a narrow angle formed by the inclined surface 13β and the upper surface of the cover portion 24β is defined as an inclination angle θβ. The bending element 12β refracts the irradiation light Mβ emitted from the light source 16β by the inclined surface 13β and converts the path of the irradiation light Mβ so as to go to the subject 10β. Further, the bending element 12β totally reflects the scattered reflected light Lβ reflected from the subject 10β by the inclined surface 13β, and converts the path of the scattered reflected light Lβ in the positive direction of the Y axis inside the cover portion 24β. is there. Scattered reflected light Lβ reflected from the subject 10β that has been totally reflected by the inclined surface 13β travels to a reflection surface 17β described later. Thus, the inclined surface 13β of the bending element 12β transmits the irradiation light Mβ and totally reflects the scattered reflected light Lβ. Therefore, a material having a refractive index larger than the refractive index of the space between the cover portion 24β and the substrate portion 26β above the light source 16β is used for the cover portion 24β. For example, a visible light absorption type polycarbonate resin or acrylic resin having a refractive index of about 1.5 is used for the cover portion 24β, and the space may be an air layer. That is, an aluminum reflective film or the like is not deposited on the inclined surface 13β of the bending element 12β in order to totally reflect the scattered reflected light Lβ.

Further, a notch portion 19β for preventing stray light is formed in the positive direction of the Y axis from the end of the total reflection surface of the bending element 12β on the contact surface 24bβ side of the cover portion 24β.

The imaging reflecting mirror 14β reflects the scattered reflected light Lβ from the subject 10β and forms an image of the subject 10β on the image sensor 15β. The imaging reflecting mirror 14β is located above the image sensor 15β and on the positive side of the Y axis with respect to the image sensor 15β, and is located on a portion of the back surface of the cover portion 24β that is not in contact with the substrate portion 26β. A recess is formed on the back surface. For example, a toroidal surface having different curvatures in two orthogonal directions is formed on the imaging reflecting mirror 14β. The imaging reflecting mirror 14β reflects the scattered reflected light Lβ on this toroidal surface so as to form an image on the image sensor 15β. In order to efficiently reflect the scattered reflected light Lβ in the imaging reflecting mirror 14β, a reflective film made of metal such as aluminum, nickel, gold, silver, dielectric dichroic film, etc. is formed on the toroidal surface of the imaging reflecting mirror 14β. Is vapor-deposited.

In the above description, the imaging reflector 14β is formed with, for example, a toroidal surface. However, the present invention is not limited to this. Any material that can form an image can be used.

The reflecting surface 17β causes the scattered reflected light Lβ totally reflected by the inclined surface 13β to be incident on the imaging reflecting mirror 14β and the scattered reflected light Lβ reflected from the imaging reflecting mirror 14β to be incident on the image sensor 15β. The reflected reflected light Lβ is reflected. The reflection surface 17β is located above the image sensor 15β and on the upper surface of the cover portion 24β. The reflective surface 17β is formed by depositing a reflective film on the upper surface of the cover portion 24β. Since the reflective film forming the reflective surface 17β is exposed to the outside and can be seen well by the user, it is desirable that the reflective film be as inconspicuous as possible. For example, when the wavelength of light emitted from the light source 16β is an infrared wavelength outside the visible wavelength (for example, 800 nm or more), the reflective film that forms the reflecting surface 17β is red in the wavelength band of 800 nm or more emitted from the light source 16β. Any device that reflects external light and transmits light having a visible wavelength band of 800 nm or less may be used. As described above, by appropriately setting the wavelength of the light emitted from the light source 16β and the reflectance and transmittance characteristics of the reflective film forming the reflective surface 17β, the scattered reflected light Lβ from the subject 10β is efficiently reflected. In addition, it is possible to form the reflecting surface 17β that is not conspicuous in appearance.

Further, when the wavelength of light emitted from the light source 16β is an infrared wavelength outside the visible wavelength (for example, 800 nm or more), the material of the cover portion 24β is a visible light absorption type polycarbonate resin or acrylic resin that transmits only infrared light. You can do it. By forming the cover part 24β with such a material, visible light components can be blocked by the cover part 24β from unnecessary light entering from the outside of the cover part 24β. As described above, by forming the reflection surface 17β that reflects infrared light, the infrared light component of the unnecessary light can be blocked by the reflection surface 17β. By blocking unnecessary light incident on the optical pointing device 30β, malfunction due to the unnecessary light can be prevented.

Furthermore, when coloring the surface of the cover part 24β, which is the surface of the optical pointing device 30β, for example, only the wavelength band of a predetermined color such as green is provided on the upper surface of the cover part 24β and the upper surface of the reflection surface 17β. May be coated with a material having a characteristic of reflecting other wavelengths and transmitting other wavelengths. By coating the upper surface of the cover portion 24β and the upper surface of the reflecting surface 17β with a material having such characteristics, a desired color can be formed on the surface of the optical pointing device 30β without impairing the optical characteristics of the optical pointing device 30β. Can be attached.

The reflecting surface 18β reflects the scattered reflected light Lβ reflected from the imaging reflecting mirror 14β and reflected by the reflecting surface 17β toward the reflecting surface 17β again. The reflective surface 18β is located above the image sensor 15β and on the positive side of the Y axis from the image sensor 15β, and is located on the back surface of the cover portion 24β. The reflective surface 18β is formed by depositing a reflective film on the back surface of the cover portion 24β. The reflective film that forms the reflective surface 18β is preferably one that reflects light efficiently. For example, the reflecting surface 18β is formed by depositing a metal such as aluminum, nickel, gold, silver, or a dielectric dichroic film.

As described above, in the optical pointing device 30β of the present embodiment, the cover portion 24β is assembled above the substrate portion 26β with reference to the side surface and the upper surface of the transparent resin 20β of the substrate portion 26β. The cover portion 24β has contact surfaces 24aβ and 24bβ serving as a reference for making a decision on the transparent resin 20β of the substrate portion 26β. The contact surface 11β, the bending element 12β, the imaging reflector 14β, and the front and rear flanges 25β and the side flange 27β are integrally formed. For this reason, the contact surfaces 24aβ and 24bβ, the contact surfaces 11β, the bending element 12β, the imaging reflecting mirror 14β, the front and rear side flanges 25β, and the side surface side flanges 27β are arranged with high mold tolerance. Therefore, the positional relationship with the cover portion 24β can be arranged with high accuracy by bringing the contact surfaces 24aβ and 24bβ of the cover portion 24β into contact with the side surfaces and the upper surface of the transparent resin 20β of the substrate portion 26β. Therefore, since each part and each element constituting the optical pointing device 30β can be arranged with high accuracy, the optical pointing device 30β with high detection accuracy of the subject 10β can be realized.

In the optical pointing device 30β having the above-described configuration, a path where the light emitted from the light source 16β is reflected by the subject 10β and enters the image sensor 15β will be described with reference to FIG.

As shown in FIG. 27A, first, the irradiation light Mβ irradiated from the light source 16β is refracted and transmitted by the inclined surface 13β of the bending element 12β and reaches the contact surface 11β. When the subject 10β is on the contact surface 11β, the irradiation light Mβ emitted from the light source 16β is scattered and reflected on the surface of the subject 10β that is in contact with the contact surface 11β. The scattered reflected light Lβ reflected by the surface of the subject 10β is totally reflected by the inclined surface 13β of the bending element 12β, and the path is changed in the positive direction of the Y axis. Scattered reflected light Lβ totally reflected by the inclined surface 13β is reflected by the reflecting surface 17β and reaches the imaging reflecting mirror 14β. Then, the scattered reflected light Lβ is reflected back by the imaging reflecting mirror 14β, reflected one after another by the reflecting surface 17β, the reflecting surface 18β, and the reflecting surface 17β, and finally enters the imaging element 15β.

As a result, signal information relating to the amount and direction of movement of the subject 10β when the subject 10β is moved can be obtained from the signal component obtained by image processing of the image picked up on the image sensor 15β by the scattered reflected light Lβ on the circuit board 21β. .

By the way, in the optical pointing device 30β having the above configuration, the bending element 12β and the imaging reflecting mirror 14β are integrated in the cover portion 24β, and the reflected light from the subject 10β is close to the light source 16β and the imaging device 15β. Alternatively, direct light from the light source 16β may directly enter the image sensor 15β without passing through the imaging mirror 14β.

As a result, as shown in FIG. 28, for example, a similar image by direct light from the light source 16β passing through the optical path M1β can be obtained only when the subject 10β moves, so that the signal information is obtained. Not only cannot be obtained, but the non-moving image overlaps the moving image, hiding the movement of the image, so that accurate signal information cannot be obtained. Here, in the following description, light passing through the optical path of the scattered reflected light Lβ from which signal information is obtained is referred to as signal light, and light other than the signal light is referred to as noise light. Further, noise light generated by the light source 16β inside the optical pointing device 30β is defined as stray light, and noise light generated by light incident from the outside of the optical pointing device is defined as disturbance light. It is to be noted that stray light is imaged reflection of direct light incident on the image sensor 15β directly from the light source 16β without passing through the subject 10β and the imaging reflector 14β and scattered light from the subject 10β based on the light from the light source 16β. Light directly incident on the image sensor 15β without passing through the mirror 14β.

That is, the S / N ratio of the image sensor 15β is expressed by Signal (signal light) / Noise (noise light), and it is necessary to remove noise light that lowers the S / N ratio.

Therefore, in the present embodiment, in order to solve this problem, in the outer peripheral region of the imaging reflecting mirror 14β, the direct light from the light source 16β, the scattered light from the subject 10β, or other disturbance light reach. The structure S1β is provided that suppresses the incident light as noise light to the imaging element 15β by changing the optical path of the light reflected by the outer peripheral region or the light transmitted through the outer peripheral region.

Specifically, for example, as shown in FIG. 27B, structures S1β are provided on the same plane as the imaging mirror 14β and on both sides in the lateral direction of the imaging mirror 14β. FIG. 27B is a perspective view of the cover portion 24β of FIG. 27A as viewed from the Z-axis direction negative toward the positive direction.

In the optical pointing device 30β provided with the structure S1β, as shown in FIG. 29, the optical path of the stray light M1β is changed to the stray light M1′β, and the light is changed to a light beam in a direction different from that of the image pickup device 15β. Further, even when the light is transmitted and refracted, the optical path is changed to stray light M1 ″ β, and the light beam is changed in a direction different from that of the image sensor 15β, so that it does not become stray light.

Here, the structure S1β is preferably formed of a scattering surface. By using a scattering surface as the structure S1β, light from the light source 16β that does not pass through the subject 10β that causes stray light is scattered on the scattering surface. Therefore, it is possible to reliably prevent the light emitted from the light source 16β from becoming stray light without being reflected by the subject 10β.

More specifically, the structure S1β is preferably made of a prism. Since this prism reflects incident light, it reflects stray light. Therefore, stray light can be reliably prevented from entering the imaging surface. Further, since the prism transmits and refracts the stray light, the stray light can be reliably prevented from entering the imaging surface.

In the structure S1β composed of the prism, the amount of stray light incident on the imaging surface when the apex angle of the prism is 90 °, the pitch is 44 μm, and the depth is 23 μm was examined. As a result, when the total light amount incident on the imaging surface is 100%, the stray light amount is 0.022% when the structure S1β is not provided, whereas when the structure S1β is provided. The stray light amount was 0.002%, and the stray light amount was reduced to 1/10.

Here, as a specific shape of the structure S1β made of a prism, for example, those shown in FIGS. 30 to 32 can be considered.

For example, as shown in FIGS. 30A and 30B, a structure S1 ₁ β having a prism cross-sectional shape of a right triangle can be formed. This structure S1 ₁ β is easy to cut, and in the optical pointing device 30β in which the contact surface 11β and the imaging reflecting mirror 14β are formed integrally with the cover 24β, cutting is performed simultaneously with the imaging reflecting mirror 14β. Since it can be processed, there is an advantage that the production efficiency is improved.

Further, as shown in FIGS. 31A and 31B, the prism cross-sectional shape may be a circular cross-sectional shape, that is, the structure S1 ₂ β in which the prism shape has an uneven spherical surface. Since this structure S1 ₂ β can be expected to have a scattering effect compared to the structure S1 ₁ β, stray light can be prevented from entering the imaging surface, and the intensity of stray light can be further reduced.

Further, as shown in FIGS. 32 (a) and 32 (b), the prism shape can be a structure S1 ₃ β having a square-convex uneven surface. Also in the structure S1 ₃ β, the optical pointing device 30β in which the cutting process is easy and the contact surface 11β and the imaging reflecting mirror 14β are integrally formed with the cover 24β is performed simultaneously with the imaging reflecting mirror 14β. Since it can be cut, the production efficiency is improved. Further, since the prism shapes are provided on both sides compared to the one-side prism shape, there is an advantage that stray light can be efficiently prevented.

On the other hand, as another example of the range in which the direct light from the light source 16β and the scattered light from the subject 10β reach the outer peripheral region of the imaging mirror 14β, for example, the one shown in FIG. FIG. 33 is a view showing stray light M2β and stray light M3β passing through the front and rear flanges 25β and the side flanges 27β in the cover portion 24β.

In this embodiment, in order to cope with this stray light M3β, as shown in FIG. 34, a structure S2β is provided on the side flange 27β. Similarly to the structure S1β, the structure S2β can also be a structure S2β made of a prism. As a result, the stray light M3β passing through the side flange 27β is changed into a stray light M3′β, and the light path is changed to a light beam in a direction different from that of the image pickup device 15β. Also, when the structure S2β is provided to transmit and refract the light, the stray light M3β is changed to a stray light M3 ″ β and changed to a light beam in a direction different from that of the image pickup device 15β, so that it does not become stray light.

Further, in order to cope with the stray light M2β, as shown in FIG. 35, it is possible to provide a structure S3β on the front and rear flange 25β. Similarly to the structure S1β, the structure S3β can also be a structure S3β made of a prism. As a result, the stray light M2β passing through the front and rear flanges 25β is changed to a stray light M2′β, and the light path is changed to a light beam in a direction different from that of the image pickup device 15β. In addition, when the structure S3β is provided to transmit and refract the light, the stray light M2β is changed to a stray light M2 ″ β and is changed to a light beam having a direction different from that of the imaging element 15β, so that the stray light is not generated.

As described above, the optical pointing device 30β of the present embodiment includes the light source 16β that irradiates light on the contact surface 11β of the subject 10β, and the imaging reflector 14β that forms an image of the scattered light from the subject 10β on the image sensor 15β. And. Therefore, by adopting such an optical pointing device 30β, the optical path length of the optical system can be made longer, the length in the vertical direction can be made smaller than the optical path length, and miniaturization can be achieved.

However, in such an optical pointing device 30β, the direct light from the light source 16β, the scattered reflected light Lβ from the subject 10β or other disturbance light directly enters the image sensor 15β without passing through the imaging reflector 14β. In some cases, such stray light or the like reduces the S / N (Signal / Noise) of the image sensor.

On the other hand, in the present embodiment, the outer peripheral area of the imaging reflecting mirror 14β, which is within the range where the direct light from the light source 16β, the scattered light from the subject 10β, or other disturbance light reaches, The structure S1β is provided that suppresses the incident light as noise light by changing the optical path of the reflected light or the light transmitted through the outer peripheral region. The structure S1β is made of a scattering surface such as a prism.

Therefore, the structure S1β suppresses light and the like from the light source 16β that is not reflected by the subject 10β that causes stray light and the like from being reflected in a specific direction and entering the imaging element 15β as noise light. . As a result, it is possible to prevent the light emitted from the light source 16β from becoming stray light without being reflected by the subject 10β.

Further, the structure S1β is not a new shielding wall because it suppresses incident light as noise light to the imaging element 15β by changing the optical path of the light reflected by the outer peripheral region or transmitted through the outer peripheral region. .

Therefore, it is possible to provide the optical pointing device 30β that can reduce the influence of stray light on the image data captured by the image sensor 15β without providing a new shielding wall.

Further, in the optical pointing device 30β of the present embodiment, the contact surface 11β, the imaging reflecting mirror 14β, and the structure S1β are integrally provided on the cover portion 24β that is a light guide member that propagates scattered light from the subject 10β. ing.

Thereby, since the structure S1β is integrally formed with the optical system of the optical member such as the contact surface 11β and the imaging reflecting mirror 14β, the optical member and the structure S1β can be assembled with high accuracy. The number of parts can be reduced.

Further, in the subject 10β of the present embodiment, the structures S1β are provided on both sides of the imaging reflector 14β in the lateral direction. As a result, the structure S1β can be formed simultaneously with the formation of the imaging reflector 14β, so that the manufacturing efficiency of the structure S1β is improved.

Further, in the optical pointing device 30β of the present embodiment, the cover portion 24β as a light guide member also serves as a cover member. As a result, it is possible to assemble the light guide member with higher accuracy than when the cover member and the light guide member are attached by separate members, and the number of components can be reduced.

[Tenth embodiment]
A tenth embodiment of the present invention will be described with reference to FIGS. FIG. 36 is a schematic cross-sectional view showing an optical pointing device 40β of the tenth embodiment. As shown in FIG. 36, in the present embodiment, a lens 42β as an imaging element is used in place of the imaging reflector 14β made of the reflecting mirror as the imaging element in the ninth embodiment. Is different.

In the optical pointing device 40β of the present embodiment, as shown in FIG. 36, the image of the subject 10β such as the fingertip is captured as scattered reflected light Lβ from the contact surface 11β which is the surface on the upper side in the vertical direction of the bending element 12β. It is. The scattered reflected light Lβ reflects the inclined surface 43β of the bending element 12β, forms an image by the lens 42β as an imaging element, reflects the inclined surface 44β, and is captured as image data by the imaging element 15β. Changes in the contact surface 11β are extracted from the image data obtained from the image sensor 15β by image processing, and the amount and direction of movement of the subject 10β can be obtained.

In this case, since the scattered reflected light Lβ has a role of transmitting the change of the contact surface 11β to the imaging element 15β, the scattered reflected light Lβ is signal light. Further, a light source 16β constituting a light source module for illuminating the subject 10β is disposed below the bending element 12β. Therefore, in the present embodiment, as shown in the figure, stray light M4β is cited as stray light for the signal light of the scattered reflected light Lβ.

Therefore, in the present embodiment, in order to prevent the stray light M4β from entering the image sensor 15β, the structures S4β are provided above and below in the vertical direction on the same plane as the lens 42β. By providing this structure S4β, as shown in FIG. 36, stray light M4β is reflected in a direction different from that of the image sensor 15β and changed to stray light M4′β. Therefore, the stray light M4β is incident on the image sensor 15β. Absent. Further, even when the structure S4β is provided in order to transmit and refract it, the stray light M4β changes its optical path to the stray light M4 ″ β and changes to a light beam in a direction different from that of the image sensor 15β, so that it does not become stray light.

Furthermore, in the present embodiment, the structure S4β and the lens 42β are on the same plane. Therefore, in order to reduce stray light, for example, when using an aperture as a well-known member, it is necessary to assemble the lens 42β and the aperture as separate members when using the aperture. On the other hand, in the present embodiment, the structure S4β is integrated with the lens 42β, so that the alignment is easy. For this reason, it can assemble with high precision compared with the case where an aperture is used.

In the above description, the structure S4β is provided vertically above and below the same plane as the lens 42β. However, the structure S4β is not necessarily limited to this, and for example, as shown in FIG. The structures S5β provided on both sides in the lateral direction can be used.

Thereby, since the stray light M5β from the light source 16β is changed in optical path to the stray light M5′β and does not enter the image pickup device 15β, it is possible to prevent the performance of the optical pointing device 40β from being deteriorated. Further, even when the structure S5β is provided to transmit and refract it, the stray light M5β is changed to a stray light M5 ″ β and changed to a light beam having a direction different from that of the imaging element 15β, so that it does not become stray light.

As described above, in the optical pointing device 40β of the present embodiment, the structures S4β and S5β are provided on both sides in the vertical direction or both sides in the lens 42β as the imaging element.

Thereby, since the structures S4β and S5β can be formed at the same time when the lens 42β as the imaging element is formed, the manufacturing efficiency of the structures S4β and S5β is improved.

[Eleventh embodiment]
Finally, an electronic apparatus equipped with the optical pointing device 30β / 40β of the present embodiment will be described with reference to FIGS. FIGS. 38A, 38B, and 38C are views showing the appearance of a cellular phone 60β as an electronic device on which any one of the optical pointing devices 30β and 40β is mounted. 38A is a front view of the mobile phone 60β, FIG. 38B is a rear view of the mobile phone 60β, and FIG. 38C is a side view of the mobile phone 60β. In FIGS. 38 (a), (b), and (c), an example is shown in which the cellular phone 60β is used as the electronic device, but the present invention is not limited to this. The electronic device may be, for example, a PC (particularly a mobile PC), a PDA, a game machine, a remote controller such as a television, or the like.

38 (a), (b), and (c), the mobile phone 60β includes a monitor-side casing 61β and an operation-side casing 62β. The monitor-side housing 61β includes a monitor unit 65β and a speaker unit 66β, and the operation-side housing 62β includes a microphone unit 63β, a numeric keypad 64β, and an optical pointing device 30β, for example. The optical pointing device 30β mounted on the mobile phone 60β is not necessarily limited to this, and can also be applied to the optical pointing device 40β.

In this embodiment, as shown in FIG. 38A, the optical pointing device 30β is arranged above the numeric keypad 64β. However, the arrangement method and the direction of the optical pointing device 30β are described here. It is not limited.

The speaker unit 66β outputs sound information to the outside, and the microphone unit 63β inputs sound information to the mobile phone 60β. The monitor unit 65β outputs video information. In the present embodiment, the monitor unit 65β displays input information from the optical pointing device 30β.

Note that, as shown in FIGS. 38A, 38B, and 38C, the cellular phone 60β of the present embodiment includes an upper casing (monitor-side casing 61β) and a lower casing (operation-side casing). 62β) is connected via a hinge as a so-called foldable mobile phone 60β. Since the folding type is mainstream as the cellular phone 60β, a folding type cellular phone is given as an example in this embodiment, and the cellular phone 60β on which the optical pointing device 30β can be mounted is a folding type. It is not limited to.

In recent years, a folding mobile phone 60β having a thickness of 10 mm or less in a folded state has also appeared. If the portability of the mobile phone 60β is taken into consideration, its thickness is an extremely important factor. In the operation-side casing 62β shown in FIGS. 38A, 38B, and 38C, components that determine the thickness of the operation-side casing 62β except for an internal circuit board (not shown) are a microphone unit 63β, a numeric keypad 64β, and an optical pointing device. 30β. Among these, the thickness of the optical pointing device 30β is the largest, and the thinning of the optical pointing device 30β directly leads to the thinning of the mobile phone 60β. Therefore, the optical pointing device of the present invention that can be thinned as described above is a preferred invention for an electronic device that needs to be thinned, such as the cellular phone 60β.

As described above, the cellular phone 60β as the electronic apparatus of the present embodiment includes the optical pointing devices 30β and 40β. Therefore, when using the cover portion 24β in which the light guide member and the imaging reflecting mirror 14β or the lens 42β are integrated, the optical pointing devices 30β and 40β that are less affected by stray light on the image data captured by the image sensor 15β are provided. The mobile phone 60β provided can be provided.

In each of the ninth to eleventh embodiments, there is provided an optical pointing device that can reduce the influence of stray light on image data captured by an image sensor without providing a new shielding wall, and an electronic apparatus including the same. . The optical pointing device 30β includes a light source 16β that irradiates light on the contact surface 11β of the subject 10β, and an imaging reflecting mirror 14β that forms an image of the scattered light from the subject 10β on the image sensor 15β. The light reflected by the outer peripheral region or transmitted through the outer peripheral region is within the outer peripheral region of the imaging mirror 14β and reaches the direct light from the light source 16β, the scattered light from the subject 10β, or other disturbance light. A structure S1β that suppresses light from entering the imaging element 15β as noise light is provided.

In the optical pointing device according to the aspect of the invention, the light guide type optical member may change the direction of the reflected light from the subject by changing the direction of the reflected light from the subject, the contact surface with which the subject is in contact, and the imaging reflective portion. It is preferable that the optical path conversion part to guide is integrally formed.

According to the above configuration, the light guide type optical member has a contact surface with which the subject comes into contact, an imaging reflection unit that guides the guided light to the imaging reflection unit, and reflection from the subject reflected by the contact surface. An optical path conversion unit that converts the optical path of light and guides it to the imaging reflection unit, and these are integrally formed. That is, an optical system that is an essential component in the optical pointing device is integrally formed. As a result, even if the optical path length of the optical system is increased and aberrations are suppressed, the length of the light guide type optical member in the vertical direction can be made smaller than the optical path length. Therefore, further downsizing and thinning of the optical pointing device can be realized. Moreover, by integrally molding, the light guide type optical member can be assembled with high accuracy and the number of parts can be reduced.

In the optical pointing device of the present invention, the stray light prevention unit may be a prism that refracts the guided light.

According to the above configuration, since the stray light prevention unit is formed of a prism, the light source light that has not been reflected by the subject that causes stray light is reflected in a specific direction by the stray light prevention unit. Therefore, it is possible to reliably prevent the light emitted from the light source from becoming stray light without being reflected by the subject.

In the optical pointing device of the present invention, the stray light prevention unit may be composed of a refractive surface that scatters the guided light.

According to the above configuration, since the stray light prevention unit is formed of a refracting surface, the light source light that is not reflected by the subject that causes stray light is refracted by the stray light prevention unit. Therefore, it is possible to reliably prevent the light emitted from the light source from becoming stray light without being reflected by the subject.

In the optical pointing device of the present invention, the stray light prevention unit may be composed of a light shielding member that shields light that has been shielded.

According to the above configuration, since the stray light prevention unit is made of the light shielding member, the stray light prevention unit shields the light source light that has not been reflected by the subject causing the stray light. Therefore, it is possible to reliably prevent the light emitted from the light source from becoming stray light without being reflected by the subject.

The light shielding member is preferably made of a black film. Since the black film has a property of absorbing light, the stray light prevention unit absorbs light source light that has not been reflected by the subject that causes stray light. Therefore, it is possible to reliably reduce the influence of stray light and provide an optical pointing device with high subject detection accuracy.

In the optical pointing device of the present invention, it is preferable that the stray light prevention unit is formed integrally with the contact surface, the imaging reflection unit, and the optical path conversion unit.

According to the above configuration, the stray light prevention unit is integrally formed with the optical system of the light guide type optical member. Therefore, the light guide type optical member and the stray light prevention unit can be assembled with high accuracy, and the number of parts can be reduced.

In the optical pointing device of the present invention, it is preferable that a reflection film for reflecting the guided light is formed on the prism surface.

According to the above configuration, since the reflection film is formed on the surface of the prism, the range of angles that can be reflected by the stray light prevention unit can be expanded. Therefore, it is possible to reliably prevent the light emitted from the light source from becoming stray light without being reflected by the subject.

In the optical pointing device of the present invention, the imaging reflecting portion may be a spherical surface, an aspherical surface, or a toroidal surface in which the curvature of the surface in the light guide direction and the curvature of the surface orthogonal to the light guide direction are different from each other. Good.

According to the above configuration, the imaging reflecting part has a spherical surface, an aspherical surface, or a toroidal surface. Accordingly, the curvature of the imaging reflecting portion is made spherical, non-spherical based on optical aberrations such as spherical aberration and coma aberration generated from the configuration of the optical system of the optical pointing device, and the distortion amount of the image projected on the image sensor. By appropriately setting the spherical surface or the toroidal surface, the optical characteristics of the light guide type optical member of the optical pointing device can be further improved.

In the optical pointing device of the present invention, the optical path changing unit includes a prism that refracts reflected light from the subject, a reflective diffractive element that deflects reflected light from the subject, a reflective Fresnel lens, or a reflective hologram lens. You may be comprised from either.

According to the above configuration, since the optical path conversion unit is configured by the prism (total reflection surface), the optical path conversion unit can be configured easily. Further, since the prism totally reflects incident light, the light utilization efficiency is highest with respect to optical path deflecting means such as a reflection type diffraction element, a reflection type Fresnel lens, or a reflection type hologram lens, which will be described later. As a result, the image projected onto the image sensor becomes brighter, and the S / N ratio can be improved.

On the other hand, when the optical path conversion unit is composed of a reflection type diffractive element, a reflection type Fresnel lens, or a reflection type hologram lens (that is, the optical path that the optical path conversion unit deflects the direction of reflected light from the subject and guides it to the imaging means In the case of a deflection unit), the light use efficiency is lower than that of the optical path conversion unit by total reflection such as a prism. However, in particular, when the optical path deflecting unit is formed on the back surface of the light guiding type optical member, the light guiding type optical member including the function of the optical path deflecting unit can be formed without forming a concave portion therefor. Therefore, it is not necessary to form the concave portion as compared with the optical path changing portion by total reflection such as a prism in which the concave portion is formed, and therefore the thickness of the light guide type optical member can be made thin and uniform. Therefore, it is possible to reduce the thickness of the light guide optical member (that is, to reduce the thickness of the optical pointing device).

In addition, when the optical path conversion unit is a reflection hologram lens, it can have a role of correcting aberrations that cannot be corrected by the imaging reflection unit. Thereby, the imaging performance of the imaging reflection unit is improved, and the image of the subject can be clearly captured by the imaging element.

In the optical pointing device of the present invention, it is preferable that the light guide type optical member includes a light shielding film that shields light from the outside in a surface region other than the contact surface with which the subject contacts.

The light incident from the outside of the optical pointing device becomes disturbance light that is not necessary for the optical pointing device to detect the subject.

According to the above configuration, the light shielding film is formed on the surface of the light guide type optical member on the subject side so as to avoid the contact surface where the subject contacts. Thereby, the influence of disturbance light can be suppressed by the light shielding film. Therefore, the contrast of the image formed by the image sensor is improved.

In the optical pointing device of the present invention, the imaging element is provided on a substrate and is resin-sealed with a transparent resin, and the light guide optical member is in contact with the surface and side surfaces of the transparent resin. It is preferable.

According to the above configuration, the light guide type optical member is in contact with the transparent resin that seals the image pickup device provided on the substrate. Thereby, the light guide type optical member can be arranged with high accuracy while maintaining the parallelism between the light guide type optical member and the image sensor. That is, each part and each element constituting the optical pointing device can be accurately arranged. Therefore, an optical pointing device with high subject detection accuracy can be realized.

In order to solve the above-described problems, an electronic apparatus according to the present invention includes any one of the above optical pointing devices.

According to the above configuration, it is possible to provide an electronic apparatus including an optical pointing device in which the influence of stray light on the image data captured by the image sensor is reduced.

Further, in the optical pointing device of the present invention, the cutout portion prevents light reflected from the subject or direct light from the light source from directly entering the imaging element without passing through the imaging reflection portion. It is preferable that a member is provided.

Thereby, when the stray light composed of the reflected light from the subject not passing through the imaging reflecting portion or the direct light from the light source is emitted from the inside of the light guide type optical member, it is shielded by the light shielding member.

Therefore, it is possible to reliably prevent the stray light including the reflected light from the subject not passing through the imaging reflection unit or the direct light from the light source from directly entering the imaging element.

In the optical pointing device of the present invention, it is preferable that the light shielding member is made of a black film.

As a result, the black-based film has the property of absorbing light, so that stray light consisting of reflected light from the subject reflected by the notch or direct light from the light source is generated inside the light guide type optical member. It is possible to prevent the light from being reflected by the light source and reflected by the imaging reflection part and finally entering the image sensor. Therefore, it is possible to reliably reduce the influence of stray light and provide an optical pointing device with high subject detection accuracy.

Also, in the optical pointing device of the present invention, the optical path changing means can be composed of a prism that refracts reflected light from the subject.

Thereby, by using a general prism as the optical path changing means, the optical path changing means can be easily configured. Further, since the prism totally reflects incident light, the light utilization efficiency is highest with respect to optical path deflecting means such as a reflection type diffraction element, a reflection type Fresnel lens, or a reflection type hologram lens, which will be described later. As a result, the image projected onto the image sensor becomes brighter, and the S / N ratio can be improved.

Further, in the optical pointing device of the present invention, the optical path changing means comprises optical path deflecting means for deflecting the direction of reflected light from the subject and guiding it to the imaging reflecting section, and the optical path deflecting means comprises: It may be configured by any of a reflection type diffraction element, a reflection type Fresnel lens, and a reflection type hologram lens.

Thereby, the light path conversion means composed of the light path deflection means is less efficient in using light than the light path conversion means by total reflection such as a prism. However, when the optical path deflecting unit is formed on the side opposite to the contact surface of the light guiding type optical member, the light guiding type optical member including the function of the optical path deflecting unit is formed without forming a concave portion therefor. be able to. As a result, it is not necessary to form the concave portion as compared with the optical path changing means by total reflection such as a prism in which the concave portion is formed, so that the thickness of the light guide type optical member can be made thin and uniform.

Therefore, it is possible to reduce the thickness of the light guide type optical member, thereby realizing a thin optical pointing device.

In addition, when the optical path deflecting means is a reflection hologram lens, it can have a role of correcting aberrations that cannot be corrected by the imaging reflection section. As a result, the imaging performance of the imaging reflection unit is improved, and the image of the subject can be clearly captured by the imaging element.

Therefore, the performance of the optical pointing device can be improved.

Further, in the optical pointing device of the present invention, it is preferable that the imaging reflection unit is constituted by any one of a spherical surface, an aspherical surface, and a toroidal surface.

Accordingly, the curvature of the imaging reflecting portion is made spherical, non-spherical based on optical aberrations such as spherical aberration and coma aberration generated from the configuration of the optical system of the optical pointing device, and the distortion amount of the image projected on the image sensor. By appropriately setting the spherical surface or the toroidal surface, the optical characteristics of the light guide type optical member of the optical pointing device can be further improved.

In the optical pointing device of the present invention, it is preferable that a shielding film that shields light from the outside is provided in a surface region of the light guide type optical member other than the contact surface with which the subject contacts.

That is, in the light coming from the outside of the optical pointing device, the light from other than the subject on the contact surface that can obtain good characteristics in the imaging reflecting portion becomes disturbance light for the optical pointing device.

However, in the present invention, the surface region other than the contact surface is provided with a shielding film that shields light from the outside, so that the influence of disturbance light can be suppressed. Therefore, it is possible to improve the contrast of an image photographed by the image sensor.

Further, in order to solve the above problems, an electronic apparatus according to the present invention is characterized by including the above-described optical pointing device.

According to the above invention, it is possible to provide an electronic apparatus including an optical pointing device that is less affected by stray light when using a light guide type optical member in which an optical path changing unit and an imaging reflection unit are integrated.

In the optical pointing device of the present invention, it is preferable that the contact surface, the imaging element, and the structure are integrally provided on a light guide member that propagates scattered light from a subject.

Thereby, since the structure is integrally formed with the optical system of the optical member such as the contact surface and the imaging element, the optical member and the structure can be assembled with high accuracy and the number of parts can be reduced. be able to.

In the optical pointing device of the present invention, it is preferable that the structures are provided on both sides in the vertical direction or both sides in the horizontal direction of the imaging element.

Thereby, since the structure can be formed at the same time when the imaging element is formed, the manufacturing efficiency of the structure is improved.

In the optical pointing device of the present invention, it is preferable that the light guide member also serves as a cover member.

This makes it possible to assemble the light guide member with higher accuracy than when the cover member and the light guide member are attached as separate members, and reduce the number of parts.

In order to solve the above problems, an electronic apparatus according to the present invention is characterized by including the above-described optical pointing device.

According to the above invention, it is possible to provide an electronic apparatus including an optical pointing device in which the influence of stray light on image data captured by an image sensor is reduced.

The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

The present invention relates to an optical pointing device as an input device that can be mounted on a portable information terminal (electronic device) that is particularly required to be reduced in size and thickness, such as a mobile phone and a PDA (Personal Digital Assistant), and an electronic device including the same. Can be suitably used. Further, the present invention can be used for an input device such as a PC or a mobile phone, and can be preferably used particularly for a portable device that is required to be small and thin.

10 Subject 11 Contact surface 12 Diffraction element (optical path conversion unit, prism)
12 'Diffraction element (optical path changer, reflection type diffraction element)
13 Inclined surface 14 Imaging element (imaging reflection part)
15 Image sensor 16 Light source 17 Reflecting surface (optical path conversion unit)
18 Reflecting surface (light path conversion part)
19A Stray light prevention prism (stray light prevention part)
24 Cover (light guide type optical member)
28A / 28B Light shielding films 30, 30a, 30b, 107 Optical pointing device 100 Mobile phone (electronic equipment)
10α Subject 11α Contact surface 12α Bending element (optical path changing means, prism)
13α Inclined surface 14α Imaging element (imaging reflector)
15α Image sensor 16α Light source 17α / 18α Reflecting surface 19α Notch portion 19aα Light shielding film 20α Transparent resin 21α Circuit board 24α Cover portion (light guide type optical member)
24aα Y direction contact surface 24bα Z direction contact surface 24cα Bottom surface 25α Flange 26α Substrate portion 26aα Bottom surface 30α Optical pointing device 40α Optical pointing device 50α Optical pointing device 51aα Shielding film (shielding film)
51bα Shielding film 60α Mobile phone Lα Reflected light from subject L1α / L2α Stray light from subject Mα Irradiated light from light source M1α / M2α Stray light from light source Pα Window area θα Inclination angle 10β Subject 11β Contact surface 12β Bending element 13β Inclined surface 14β Imaging mirror (imaging element)
15β Image sensor 16β Light source 17β / 18β Reflective surface 19β Notch portion 20β Transparent resin 21β Circuit board 24β Cover portion 24aβ Y-direction contact surface 24bβ Z-direction contact surface 24cβ Bottom surface 25β Front and rear flanges 26β Substrate portion 26aβ Bottom surface 27β Side surface Side flange 30β Optical pointing device 40β Optical pointing device 42β Lens (imaging element)
43β Inclined surface 44β Inclined surface 60β Mobile phone Lβ Scattered reflected light Mβ Light irradiated from light source M1β to M5β Stray light from light source S1β to S5β Structure S1 ₁ β to S1 ₃ β Structure θβ Inclination angle

Claims (23)

A light source that irradiates light to a subject, a light guide type optical member that reflects light reflected from the subject and guides the inside, and an image sensor that receives light guided by the light guide type optical member An optical pointing device comprising:
The light guide type optical member has an imaging reflection part that guides the guided light to the image sensor,
Furthermore, a stray light prevention unit that changes the path of light that is emitted from the light source and enters the image sensor without passing through the imaging reflection unit is provided on the back surface of the light guide type optical member on which the light source and the image sensor are provided. An optical pointing device comprising: The light guide type optical member integrally includes the imaging reflection unit, a contact surface with which the subject contacts, and an optical path conversion unit that converts the direction of reflected light from the subject and guides it to the imaging reflection unit. The optical pointing device according to claim 1, wherein the optical pointing device is formed. 3. The optical pointing device according to claim 1, wherein the stray light prevention unit is a prism that refracts the guided light. 3. The optical pointing device according to claim 1 or 2, wherein the stray light prevention unit comprises a refractive surface that scatters the guided light. 3. The optical pointing device according to claim 1, wherein the stray light prevention unit is formed of a light shielding member that shields light that has been shielded. 3. The optical pointing device according to claim 2, wherein the stray light prevention unit is formed integrally with the contact surface, the imaging reflection unit, and the optical path conversion unit. 4. The optical pointing device according to claim 3, wherein a reflection film for reflecting the guided light is formed on the prism surface. 8. The imaging reflecting portion according to claim 1, wherein the imaging reflection portion has a spherical surface, an aspherical surface, or a toroidal surface in which a curvature of a surface in the light guide direction and a curvature of a surface orthogonal to the light guide direction are different from each other. The optical pointing device according to claim 1. The optical path conversion unit includes any of a prism that refracts reflected light from the subject, a reflective diffraction element that deflects reflected light from the subject, a reflective Fresnel lens, or a reflective hologram lens. The optical pointing device according to claim 2. 10. The light guide type optical member according to claim 1, further comprising a light shielding film that shields light from the outside in a surface region other than the contact surface with which the subject contacts. Optical pointing device. The imaging element is provided on a substrate and is resin-sealed with a transparent resin.
The optical pointing device according to any one of claims 1 to 10, wherein the light guide type optical member is in contact with a surface and a side surface of the transparent resin. A light source that irradiates light to a subject, a light guide type optical member that internally reflects and guides reflected light from the subject, and an imaging device that receives light guided by the light guide type optical member. An optical pointing device comprising:
The light guide type optical member includes a contact surface that contacts the subject, an imaging reflection unit that guides the guided light to the imaging element, and changes the direction of reflected light from the subject to form the image. The optical path changing means that leads to the reflecting part is formed integrally.
The imaging element is disposed below the light source side of the imaging reflection portion in the light guide type optical member,
The light guide type optical member further includes a notch for preventing the reflected light from the subject or the direct light from the light source from directly entering the image sensor without passing through the imaging reflection section. An optical pointing device characterized in that the optical pointing device is formed on at least a part of the light source side on the upper surface of the light source. The cutout portion is provided with a light shielding member that prevents light reflected from the subject or direct light from a light source from directly entering the imaging element without passing through the imaging reflection portion. The optical pointing device according to claim 12. 14. The optical pointing device according to claim 13, wherein the light shielding member is made of a black film. 15. The optical pointing device according to claim 12, 13 or 14, wherein the optical path changing means comprises a prism that refracts reflected light from the subject. The optical path conversion means comprises optical path deflection means that deflects the direction of reflected light from the subject and guides it to the imaging reflection section.
15. The optical pointing device according to claim 12, 13, or 14, wherein the optical path deflecting means is constituted by any one of a reflective diffractive element, a reflective Fresnel lens, and a reflective hologram lens. The optical pointing device according to any one of claims 12 to 16, wherein the imaging reflection unit is configured by any one of a spherical surface, an aspherical surface, and a toroidal surface. The light guide type optical member is provided with a shielding film for shielding light from the outside in a surface region other than the contact surface with which the subject contacts. The optical pointing device described. In an optical pointing device comprising: a light source that irradiates light on a contact surface of a subject; and an imaging element that forms an image of scattered light from the subject on an imaging device;
In the outer peripheral area of the imaging element and within the reach of direct light from the light source, scattered light from the subject or other disturbance light, the light reflected by the outer peripheral area or transmitted through the outer peripheral area An optical pointing device, characterized in that a structure that suppresses incident light as noise light to the image pickup device by changing an optical path is provided. 20. The optical pointing device according to claim 19, wherein the contact surface, the imaging element, and the structure are integrally provided on a light guide member that propagates scattered light from a subject. 21. The optical pointing device according to claim 19, wherein the structures are provided on both sides in the vertical direction or both sides in the horizontal direction of the imaging element. 21. The optical pointing device according to claim 20, wherein the light guide member also serves as a cover member. An electronic apparatus comprising the optical pointing device according to any one of claims 1 to 22.

Images