JP2016005076A - Lighting system, image sensor unit, image reading device, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the size of a configuration that emits light emitted from a light source from a light emission surface of a light guide body to irradiate a lighting target body with the light.SOLUTION: There is provided an image sensor unit 10 that irradiates a document P with linear light, and includes: a light source 20 that emits light; a transmission surface 27 that is formed in a rod shape and transmits a part of the light entered therein from the light source 20 to the outside; a light guide body 25 that has a light emission surface 29 that emits light entered from the outside and reflected on the transmission surface 27 to the document P at a position facing the transmission surface 27; and a reflection member 40 that is formed in a flexible sheet shape and reflects the light transmitted through the transmission surface 27 to the transmission surface 27 at a position facing the transmission surface 27.

Description

  The present invention relates to an illumination device, an image sensor unit, an image reading device, and an image forming device.

  2. Description of the Related Art An illumination device that irradiates an object to be illuminated with line-shaped light is known. The line illumination device disclosed in Patent Document 1 receives light emitted from a light emitting element from a light receiving end surface of a light guide, diffuses it on a reflection / diffusion surface, and irradiates a document through an output surface. It is configured. In addition, the line-shaped illumination device disclosed in Patent Document 1 efficiently guides light from a light-emitting element to a light guide or irradiates a document without leaking light from the light guide. It has a light guide cover that is formed by injection molding using polycarbonate resin to cover the body.

International Publication No. 2008/013234

  However, since the light guide cover described above is an injection-molded product formed by injection molding and is formed in a size that covers the entire light guide, the line illumination including the light guide cover is included. There exists a problem that an apparatus will enlarge.

  The present invention has been made in view of the above-described problems, and it is an object of the present invention to reduce the size of a configuration in which light emitted from a light source is emitted from an emission surface of a light guide to irradiate an object to be illuminated. And

The illuminating device of the present invention is an illuminating device that irradiates a body to be illuminated with light in a line shape. The illuminating device emits light, and is formed in a rod shape. And a light guide having a second surface that emits light reflected from the outside toward the first surface toward the illuminated body at a position facing the first surface; A reflective member that is formed in a flexible sheet shape and reflects light transmitted through the first surface toward the first surface at a position facing the first surface.
The image sensor unit according to the present invention includes the illumination device, a light collector that forms an image of light reflected from the illumination object by the illumination device, and an electrical signal that is formed by the light collector. And an image sensor that converts the image sensor.
The image reading apparatus of the present invention includes: the image sensor unit; and an image reading unit that reads light from the illuminated body while relatively moving the image sensor unit and the illuminated body. Features.
The image forming apparatus of the present invention includes an image reading unit that reads light from the illuminated body while relatively moving the image sensor unit, the image sensor unit, and the illuminated body, and an image on a recording medium. And an image forming unit that forms the image.

  ADVANTAGE OF THE INVENTION According to this invention, the structure which radiate | emits the light emitted from the light source from the output surface of a light guide, and irradiates a to-be-illuminated body can be reduced in size.

FIG. 1 is a cross-sectional view showing the configuration of the image sensor unit 10. FIG. 2 is a perspective view showing an appearance of MFP 100. FIG. 3 is a schematic diagram illustrating the structure of the image forming unit 113. FIG. 4 is an exploded perspective view of the image sensor unit 10. FIG. 5 is a perspective view showing a configuration around the light guide 25. FIG. 6A is a diagram illustrating a configuration of the reflecting member 40 according to the first embodiment. FIG. 6B is a diagram illustrating a configuration of the reflecting member 40 according to the first embodiment. FIG. 7 is a diagram illustrating a first internal configuration of the reflection unit 41. FIG. 8 is a diagram illustrating a second internal configuration of the reflection unit 41. FIG. 9A is a diagram illustrating a configuration of the reflecting member 70 according to the second embodiment. FIG. 9B is a diagram illustrating a configuration of the reflecting member 70 according to the second embodiment. FIG. 10 is a diagram illustrating a third internal configuration of the reflection unit 71. FIG. 11 is a diagram illustrating a configuration of the reflecting member 80 according to the third embodiment. FIG. 12 is a diagram illustrating a configuration of the reflecting member 90 according to the fourth embodiment.

Hereinafter, embodiments to which the present invention can be applied will be described in detail with reference to the drawings.
The present embodiment is an illumination device, an image sensor unit to which the illumination device is applied, and an image reading device and an image forming device to which the image sensor unit is applied. In an image reading apparatus and an image forming apparatus, an image sensor unit irradiates light on a document P as an illuminated body, and the image sensor unit converts light from the document P into an electrical signal to read an image. The object to be illuminated is not limited to the original P, and can be applied to a reading object such as a banknote. Further, the present invention can be applied to transmission reading in which an image is read by converting transmitted light transmitted through the original P into an electrical signal.
In the following description, three-dimensional directions are indicated by X, Y, and Z arrows. The X direction is the main scanning direction, the Y direction is the sub scanning direction perpendicular to the main scanning direction, and the Z direction is the vertical direction (up and down direction).

<First Embodiment>
First, the structure of a multi-function printer (MFP) that is an example of an image reading apparatus or an image forming apparatus according to the present embodiment will be described with reference to FIG. FIG. 2 is a perspective view showing an appearance of MFP 100. As shown in FIG. 2, the MFP 100 forms (prints) an image of the original P on an image reading unit 102 as an image reading unit that reads reflected light from the original P and a sheet 101 (recording paper) as a recording medium. And an image forming unit 113 as image forming means.

The image reading unit 102 has a so-called image scanner function, and is configured as follows, for example. The image reading unit 102 includes a housing 103, a platen glass 104 made of a glass transparent plate serving as a document placement unit, and a platen provided so as to be openable and closable with respect to the housing 103 so as to cover the document P. And a cover 105.
Inside the housing 103 are an image sensor unit 10 having a lighting device, a holding member 106, an image sensor unit slide shaft 107, an image sensor unit drive motor 108, a wire 109, a signal processing unit 110, a recovery unit 111, a paper feed A tray 112 and the like are stored.

  The image sensor unit 10 is, for example, a contact image sensor (CIS) unit. The holding member 106 holds the image sensor unit 10 so as to surround it. The image sensor unit slide shaft 107 guides the holding member 106 along the platen glass 104 in the sub-scanning direction. The image sensor unit drive motor 108 is a moving unit that relatively moves the image sensor unit 10 and the document P, and specifically moves a wire 109 attached to the holding member 106. The collection unit 111 is provided so as to be openable and closable with respect to the housing 103 and collects the printed sheet 101. The sheet feed tray 112 stores sheets 101 having a predetermined size.

  In the image reading unit 102 configured as described above, the image sensor unit drive motor 108 moves the image sensor unit 10 in the sub-scanning direction along the image sensor unit slide shaft 107. At this time, the image sensor unit 10 performs an image reading operation by optically reading the document P placed on the platen glass 104 and converting it into an electrical signal.

FIG. 3 is a schematic view showing the structure of the image forming unit 113.
The image forming unit 113 has a so-called printer function, and is configured as follows, for example. The image forming unit 113 is accommodated in the housing 103 and includes a conveyance roller 114 and a recording head 115 as shown in FIG. The recording head 115 includes, for example, ink tanks 116 (116c, 116m, 116y, and 116k) that include cyan C, magenta M, yellow Y, and black K inks, and ejection heads 117 ( 117c, 117m, 117y, 117k). The image forming unit 113 includes a recording head slide shaft 118, a recording head drive motor 119, and a belt 120 attached to the recording head 115.

In the image forming unit 113 configured as described above, the sheet 101 supplied from the paper feed tray 112 is transported to the recording position by the transport roller 114. The recording head 115 performs printing on the sheet 101 based on an electric signal while moving in the printing direction along the recording head slide shaft 118 by mechanically moving the belt 120 by the recording head driving motor 119. After the above-described operation is repeated until the end of printing, the printed sheet 101 is discharged to the collection unit 111 by the conveyance roller 114.
Although an image forming apparatus using an inkjet method has been described as the image forming unit 113, any method such as an electrophotographic method, a thermal transfer method, or a dot impact method may be used.

Next, the image sensor unit 10 of this embodiment will be described with reference to FIGS. 1 and 4. FIG. 1 is a cross-sectional view of the image sensor unit 10 cut along the sub-scanning direction. FIG. 4 is an exploded perspective view of the image sensor unit 10.
The image sensor unit 10 has an outline of a substantially rectangular parallelepiped whose longitudinal direction is the main scanning direction.
The image sensor unit 10 includes a cover glass 11, a frame 12, a light source 20, a light guide 25, a reflecting member 40, a circuit board 30, an image sensor 32, a light collecting body 35, and the like. Among the constituent members described above, the light source 20, the light guide 25, and the reflecting member 40 function as a lighting device. Of the above-described constituent members, the cover glass 11, the frame 12, the light guide 25, the reflecting member 40, the image sensor 32, and the light collector 35 have lengths corresponding to the dimensions in the main scanning direction of the document P to be read. It is formed.

  The cover glass 11 prevents dust from entering the frame 12. The cover glass 11 is a substantially flat plate whose longitudinal direction is the main scanning direction. The cover glass 11 is fixed to the frame 12 using, for example, a double-sided tape so as to cover the upper end of the frame 12. Although the cover glass 11 can be omitted, it is desirable to install the cover glass 11 in order to prevent dust from entering the frame 12. Moreover, the cover glass 11 is not restricted to glass, For example, the member which gave the hard coat as needed to the surface of transparent resin materials, such as an acryl and a polycarbonate, can be applied.

The frame 12 is a housing formed in a substantially rectangular parallelepiped with the longitudinal direction as the main scanning direction. The frame 12 positions and accommodates each component member inside. Specifically, as shown in FIG. 1, the frame 12 is formed with a light guide housing portion 13, a reflecting member housing portion 15, a light collector housing portion 16, and a substrate housing portion 17 along the main scanning direction. . As shown in FIG. 4, the frame 12 has a light source accommodating portion 18 formed on one side in the main scanning direction.
The light guide accommodating portion 13 accommodates the light guide 25 and has a snap-fit holding portion 14 in part. The reflection member accommodating portion 15 is formed in communication with the light guide accommodating portion 13 and accommodates the reflection member 40. The light collector housing portion 16 is formed adjacent to the light guide housing portion 13 and houses the light collector 35. The board accommodating portion 17 is formed in a concave shape on the lower side of the frame 12 and accommodates the circuit board 30. The light source accommodation unit 18 accommodates the light source 20. The frame 12 is formed of, for example, a resin material having a light shielding property colored in black. For example, polycarbonate can be used as the resin material.

The light source 20 emits light to irradiate the original P with light through the light guide 25.
FIG. 5 is a perspective view showing a configuration around the light guide 25. As shown in FIG. 5, an LED package 21 is used for the light source 20 of the present embodiment. The LED package 21 is a so-called top view type surface mount type in which an LED chip 22 is mounted on the front surface and electrodes are formed on the back surface. Since the surface mount type LED package is widely used, the cost can be reduced by applying it to the lighting device and the image sensor unit 10.

Specifically, the LED package 21 has an LED chip 22 as a light emitting unit disposed on the surface of a housing 23 formed in a substantially rectangular parallelepiped. Here, a plurality of (for example, three) LED chips 22 (22a, 22b, 22c) are sealed with a transparent resin. As the LED chips 22a, 22b, and 22c, LED chips having emission wavelengths such as red, green, and blue can be applied. Further, when the image reading apparatus is a paper sheet identification apparatus for determining the authenticity of bills or the like, it can be applied including LED chips having emission wavelengths such as infrared rays and ultraviolet rays.
The LED package 21 is accommodated in the light source accommodating portion 18 so that the LED chip 22 faces an incident surface 26 described later of the light guide 25.

The light guide 25 linearizes the light emitted from the light source 20 and guides it to the document P. The light guide 25 is formed of a transparent material such as glass or a resin material, and is formed in a rod shape that is long in the main scanning direction. As the transparent resin material, for example, an acrylic resin material can be applied.
In the light guide 25, an incident surface 26 on which light from the light source 20 is incident is formed on one end surface of both end surfaces in the main scanning direction. The incident surface 26 is disposed orthogonal to the main scanning direction. The light guide 25 is formed with a transmission surface 27 as a first surface that transmits or reflects a part of the light incident from the incident surface 26 in the main scanning direction.
Further, the light guide 25 is formed with an emission surface 29 as a second surface for emitting light incident on the light guide 25 toward the document P in the main scanning direction so as to face the document P. The emission surface 29 is formed at a position facing the transmission surface 27.
The surfaces formed in the main scanning direction other than the transmission surface 27 and the emission surface 29 each function as a reflection surface that reflects incident light.

  The reflection member 40 reflects light that has passed through the transmission surface 27 out of light incident on the light guide 25 toward the transmission surface 27. The reflection member 40 is made of a material that can reflect light having an emission wavelength emitted from the light source 20. Therefore, the light that has passed through the transmission surface 27 is reflected by the reflection member 40, enters the light guide 25 again through the transmission surface 27, and then exits from the exit surface 29 toward the document P. The

The reflecting member 40 is accommodated in the reflecting member accommodating portion 15 of the frame 12 so as to face the transmitting surface 27 and to be arranged in parallel with the transmitting surface 27. Here, the reflection member 40 is flexible and formed into a thin sheet shape. Specifically, the reflecting member 40 has a sheet shape of 50 μm to 744 μm. Therefore, since the reflecting member 40 is thin, the illumination device and the image sensor unit 10 can be reduced in size as compared with the case where a light guide cover formed of a conventional injection molded product is used.
A specific configuration of the reflecting member 40 will be described later.

  The circuit board 30 is a board on which a drive circuit for causing the LED chip 22 to emit light, an image sensor 32, and the like are mounted, and is formed in a flat plate shape whose longitudinal direction is the main scanning direction. The circuit board 30 is housed in the board housing portion 17 of the frame 12. As the circuit board 30, for example, a glass epoxy board can be applied.

  The image sensor 32 receives the light reflected from the original P and imaged by the condenser 35 and converts it into an electrical signal. The image sensor 32 is disposed on an extension line of the optical axis of the condenser 35. In the image sensor 32, a predetermined number of image sensor ICs 33 composed of a plurality of light receiving elements (photoelectric conversion elements) corresponding to the reading resolution of the image sensor unit 10 are linearly formed on the mounting surface of the circuit board 30 in the main scanning direction. Implemented in an array. The image sensor 32 only needs to be able to convert the light reflected from the document P into an electrical signal, and various known image sensor ICs can be used.

  The condenser 35 is an optical member that forms an image of the light reflected from the document P on the image sensor 32, and is formed with the longitudinal direction as the main scanning direction. The light collecting body 35 is housed in the light collecting body housing portion 16 of the frame 12. For example, a rod lens array in which a plurality of erecting equal-magnification imaging elements (rod lenses) are linearly arranged in the main scanning direction is used as the condenser 35. The condensing body 35 only needs to be able to image the reflected light on the image sensor 32, and is not limited to the rod lens array, and may use any known optical member having various condensing functions such as a microlens array.

  As shown in FIG. 1, in the image sensor unit 10 configured as described above, the light source 20 disposed in the frame 12 emits light to indicate the lower surface of the document P from the light guide 25 by an arrow L. Irradiate with light. Accordingly, the original P is irradiated with light in a line shape over the reading line S (main scanning direction). The light is reflected by the original P, so that the light is imaged on the image sensor 32 via the condenser 35. The image sensor 32 can read the image on the lower surface of the document P by converting the imaged light into an electrical signal.

  When the image sensor 32 reads the light for one scanning line, the reading operation for one scanning line in the main scanning direction of the document P is completed. After the reading operation for one scanning line is completed, the reading operation for the next one scanning line is performed in the same manner as the above-described operation with the relative movement of the image sensor unit 10 in the sub-scanning direction. As described above, the image sensor unit 10 repeats the reading operation for each scanning line while moving in the sub-scanning direction, whereby the entire surface of the document P is sequentially scanned, and the image is read by the reflected light.

As described above, since the reflecting member 40 of the present embodiment is thin, the configuration of the illumination device and the image sensor unit 10 can be reduced in size. Hereinafter, the configuration of the reflecting member 40 will be specifically described.
6A is a diagram showing a configuration of the reflecting member 40 as viewed from the direction of arrow A shown in FIG.
6B is a diagram illustrating the configuration of the light guide 25 and the reflection member 40 as viewed from the direction of the arrow B illustrated in FIG.

  The reflecting member 40 of this embodiment is used when light incident from the incident surface 26 of the light guide 25 is diffused on the light guide 25 side. Specifically, as shown in FIG. 6B, the light guide 25 is used when the transmission surface 27 has a plurality of prisms 28 as diffusion portions. The prism 28 transmits the light incident from the incident surface 26 to the outside while diffusing it. The prisms 28 are formed along the sub-scanning direction, and are densely formed so that the intervals between the prisms 28 become shorter as the distance from the incident surface 26 increases.

The reflection member 40 includes a reflection portion 41 and a mounting portion 44, and a boundary between the reflection portion 41 and the mounting portion 44 is bent at a right angle by a bent portion 45.
The reflection unit 41 reflects the light transmitted through the transmission surface 27 out of the light incident on the light guide 25 toward the emission surface 29. The reflecting portion 41 is arranged in parallel to the transmission surface 27 of the light guide 25 via the gap G, and a flat surface 42 facing the transmission surface 27 is formed. In addition, a connector 43 is coupled to the opposite side of the reflecting portion 41 from the mounting portion 44 in the main scanning direction. For example, a cable for supplying power to the LED chip 22 of the LED package 21 is connected to the connector 43. The other end of this cable is connected to the circuit board 30, for example.
The mounting portion 44 is disposed in parallel to the incident surface 26 of the light guide 25, and the LED package 21 described above is mounted thereon. Therefore, the LED chip 22 of the LED package 21 faces the incident surface 26 of the light guide 25.

  Further, the reflecting member 40 has a conducting portion 46 that conducts from the connector 43 to the electrode formed on the back side of the LED package 21 inside the reflecting portion 41 and the mounting portion 44 (see FIGS. 5 and 6A). ). Therefore, the electric power supplied from the cable through the connector 43 is fed through the conductive portion 46 and the electrode of the LED chip 22 so that the LED chip 22 emits light.

(First internal configuration)
Next, the first internal configuration of the reflector 41 will be specifically described. The first internal configuration is a configuration in which light transmitted through the transmission surface 27 among light incident on the light guide 25 is reflected by the metal sheet. In the first internal configuration, the reflective portion 41 has a thickness of 69 μm to 744 μm, preferably 120 μm to 210 μm.
FIG. 7 is a cross-sectional view showing the internal configuration of the reflecting section 41 cut along line II in FIG. 6A. The arrow U side shown in FIG. 7 is the side on which the light guide 25 is disposed, and the arrow L side is the opposite side. In FIG. 7, a part of the conduction part 46 is omitted.
The reflecting portion 41 is configured by laminating a base film 51 as a base material, a conductive portion 46 that is a metal wiring such as a copper foil, and a solder resist 56 from the U side. In the base film 51, a metal sheet 52 is sandwiched between a permeable protective sheet 53 from the U side and a protective film 54 from the L side, and an insulating adhesive 55 is formed on the protective film 54 side. The conduction part 46 is laminated via the insulating adhesive 55. The solder resist 56 is laminated so as to cover the conductive portion 46.

For the metal sheet 52, a metal such as aluminum, an aluminum alloy (for example, A8021), or copper can be used. Specifically, it is preferable to use BESPA manufactured by Sumi Light Aluminum Foil Co., Ltd. The thickness of the metal sheet 52 is preferably 25 μm or more in order to maintain an appropriate rigidity of the reflecting portion 41. On the other hand, if the thickness is too thick, the workability deteriorates, so that it is preferably 200 μm or less, or 400 μm or less.
The transmissive protective sheet 53 is a protective layer that protects the metal sheet 52, and is capable of transmitting light having the emission wavelength of the LED chip 22. For example, a cycloolefin polymer resin can be used to transmit light having emission wavelengths of ultraviolet, visible, and infrared. As the permeable protective sheet 53, it is preferable to use a ZEONOR film manufactured by Nippon Zeon Co., Ltd. The thickness of the permeable protective sheet 53 is preferably 20 μm or more because durability is lowered if it is too thin. On the other hand, if it is too thick, the light transmittance is lowered, and therefore it is preferably 200 μm or less. Accordingly, the light transmitted through the transmission surface 27 is transmitted through the transparent protective sheet 53 and reflected by the metal sheet 52.

Polyamideimide resin can be used for the protective film 54. The thickness of the protective film 54 is defined by the surface roughness RMax of the metal sheet 52, and may be thick enough to cover the unevenness, and is preferably about 1 μm to 4 μm.
As the insulating adhesive 55, a thermosetting adhesive can be used. Specifically, it is preferable to use adhesive type # 8200 and # 9300 manufactured by Toray Industries, Inc. In addition, the thickness of the insulating adhesive 55 is preferably about 10 μm to 20 μm in order to favorably adhere the conductive portion 46 that becomes the circuit wiring.
A copper foil can be used for the conductive portion 46. The thickness of the conduction part 46 is preferably 3 μm or more, or 9 μm or more in consideration of the current capacity to conduct. On the other hand, if the thickness is too thick, the workability deteriorates, and therefore it is preferably 35 μm or less, or 70 μm or less.
For the solder resist 56, epoxy resin, silicon resin, or the like can be used. Specifically, it is preferable to use a white solder resist PSR9000FLX series manufactured by Taiyo Ink and an SWR-SA series manufactured by Asahi Rubber. Further, the thickness of the solder resist 56 (T1 shown in FIG. 7) is defined by the thickness of the conductive portion 46, and the thickness of the conductive portion 46 is about +10 μm, or the surface of the solder resist 56 is smoothed to increase the light reflection efficiency. Therefore, the thickness of the conductive portion 46 is preferably about +20 μm. On the other hand, if the thickness is too large, the workability deteriorates and causes deterioration such as cracking. Therefore, the thickness of the conductive portion 46 is preferably not more than 50 μm.

According to the reflection part 41 of the first internal configuration, light incident from the incident surface 26 of the light guide 25 is transmitted while being diffused by the prism 28 formed on the transmission surface 27, and the reflection part 41 of the reflection member 40. Irradiated towards. The light irradiated on the reflection part 41 passes through the transmissive protective sheet 53, is reflected by the metal sheet 52, and enters the light guide 25 again through the transmission surface 27 of the light guide 25. The light incident on the light guide 25 again is emitted from the emission surface 29 of the light guide 25 and is applied to the document P. At this time, the prisms 28 are formed more densely with distance from the incident surface 26. Therefore, the light is diffused by the prism 28 at positions where it is difficult for light to reach, so that the light guide 25 can emit light substantially uniformly along the main scanning direction of the emission surface 29.
Aluminum and aluminum alloys can reflect light having emission wavelengths of ultraviolet, visible, and near infrared. Therefore, by using aluminum or an aluminum alloy for the metal sheet 52, even if the LED chip 22 emits light having an emission wavelength of ultraviolet, visible, or near infrared, the light irradiated toward the reflecting portion 41 is emitted. It can be reflected by the metal sheet 52.

Moreover, although the mounting part 44 does not need to reflect light, it is necessary to mount the LED package 21. FIG. Therefore, the mounting portion 44 can be configured by omitting the transmissive protective sheet 53 and the metal sheet 52 from the internal configuration of the reflecting portion 41. Specifically, it is preferable to omit the transparent protective sheet 53 and the metal sheet 52 and mount the LED package 21 on the protective film 54.
Further, when the mounting portion 44 is omitted from the reflecting member 40, the insulating portion 55, the conductive portion 46, and the solder resist 56 can be omitted from the reflecting portion 41.

(Second internal configuration)
Next, the second internal configuration of the reflection unit 41 will be specifically described. The second internal configuration is a configuration in which the light transmitted through the transmission surface 27 among the light incident on the light guide 25 is reflected by the reflective layer 62. In the second internal configuration, the thickness of the reflecting portion 41 is 73 μm to 545.5 μm, preferably 140 μm to 235 μm.
FIG. 8 is a cross-sectional view showing the internal configuration of the reflecting section 41 cut along line II in FIG. 6A. The arrow U side shown in FIG. 8 is the side where the light guide 25 is disposed, and the arrow L side is the opposite side. In FIG. 8, a part of the conduction part 46 is omitted.
The reflection part 41 is configured by laminating a coverlay film 60, a conduction part 46 that is a metal wiring such as a copper foil, and a base film 64 as a base material from the U side.
In the coverlay film 60, a polyimide film 61 and a reflective layer 62 are laminated and bonded to a base film 64 via an insulating adhesive 63. On the other hand, the base film 64 sandwiches the metal sheet 65 from above and below with the protective film 66, and an insulating adhesive 67 is formed. The conduction part 46 is laminated via an insulating adhesive 67.

For the polyimide film 61, it is preferable to use Apical NPI manufactured by Kaneka Corporation. The thickness of the polyimide film 61 is preferably about 8 μm to 12.5 μm in order to form the reflective layer 62 smoothly.
For the reflective layer 62, a white diffusion paint or a white pigment can be used. Here, the reflective layer 62 is formed with a flat surface 42 and reflects the light transmitted through the transmission surface 27. Specifically, by including barium sulfate (BaSO 4) in the white diffusing paint, it is possible to reflect light having any emission wavelength of ultraviolet, visible and infrared. Further, by including magnesium fluoride-aluminum (MgF-Al) in the white diffusing paint, it is possible to reflect light having any emission wavelength of ultraviolet, visible and infrared. Further, by including titanium oxide (TiO) in the white pigment, light having visible and infrared emission wavelengths can be reflected. The thickness of the reflective layer 62 may be any thickness that does not reduce the light reflection efficiency, and is preferably about 20 μm to 30 μm.
As the insulating adhesive 63, it is preferable to use a CM type manufactured by Arisawa Manufacturing Co., Ltd. The thickness of the insulating adhesive 63 is defined by the thickness of the conductive portion 46, and is preferably about the thickness of the conductive portion 46 + 5 μm.
In addition, the conduction | electrical_connection part 46 can be comprised similarly to a 1st internal structure.

For the metal sheet 65, a metal such as aluminum, an aluminum alloy (for example, A8021), or copper can be used. Specifically, it is preferable to use BESPA manufactured by Sumi Light Aluminum Foil Co., Ltd. The thickness of the metal sheet 65 is preferably 25 μm or more in order to maintain an appropriate rigidity of the reflecting portion 41. On the other hand, if the thickness is too thick, the workability deteriorates, so that it is preferably 200 μm or less, or 400 μm or less.
Polyamideimide resin can be used for the protective film 66. The thickness of the protective film 66 is defined by the surface roughness RMax of the metal sheet 52, and is preferably about 1 μm to 4 μm to cover the unevenness.
As the insulating adhesive 67, a thermosetting adhesive can be used. Specifically, it is preferable to use adhesive type # 8200 and # 9300 manufactured by Toray Industries, Inc. The thickness of the insulating adhesive 67 is preferably about 10 μm to 20 μm in order to favorably bond the conductive portion 46 serving as circuit wiring.

  According to the reflection part 41 of the second internal configuration, the light incident from the incident surface 26 of the light guide 25 is transmitted while being diffused by the prism 28 formed on the transmission surface 27, and the reflection part 41 of the reflection member 40. Irradiated towards. The light irradiated to the reflection part 41 is reflected by the reflection layer 62 and enters the light guide 25 again through the transmission surface 27 of the light guide 25. The light incident on the light guide 25 again is emitted from the emission surface 29 of the light guide 25 and is applied to the document P.

As described above, light having at least one of the emission wavelengths of ultraviolet, visible, and infrared can be reflected by the chemical component contained in the reflective layer 62. Therefore, the light irradiated toward the reflection part 41 can be reflected by the reflection layer 62 by changing the chemical component included in the reflection layer 62 according to the light of the emission wavelength emitted by the LED chip 22.
Further, in order to mount the LED package 21 on the mounting portion 44, it is preferable to remove the coverlay film 60 and mount the LED package 21.
In the second internal configuration, when the rigidity can be maintained by the U-side protective film 66, the reflecting portion 41 can omit the metal sheet 65 and the L-side protective film 66.
Further, when the mounting portion 44 is omitted from the reflecting member 40, the insulating adhesive 63, the conductive portion 46 and the base film 64 can be omitted from the reflecting portion 41.
The reflective layer 62 may be a retroreflecting material that refracts light using glass beads or the like.

As described above, according to the present embodiment, since the reflecting member 40 has a flexible sheet shape, the illumination device and the image sensor unit are compared with a light guide cover formed by injection molding as in the related art. 10 cross-sectional shapes can be reduced in size.
In addition, since the reflecting member 40 includes the conductive portion 46, it is not necessary to separately provide components such as a substrate in order to form the conductive portion 46, so that the number of components of the lighting device and the image sensor unit 10 can be reduced. Can do.

  Further, the reflective member 40 is bent via the curved portion 45 so that the LED package 21 is mounted on the mounting portion 44 and the LED chip 22 faces the incident surface 26 of the light guide 25. At this time, since the LED chip 22 is supplied with power through the conductive portion 46, it is not necessary to form the conductive portion 46 on the circuit board 30, and thus the circuit board 30 can be reduced in size.

<Second Embodiment>
In the first embodiment, the reflective member 40 used for the light guide 25 in which the prism 28 is formed on the transmission surface 27 has been described. In the present embodiment, a reflection member 70 used for the light guide 25 in which the prism 28 is not formed on the transmission surface 27 will be described.
FIG. 9A is a diagram showing a configuration of the reflecting member 70 as seen from the direction of arrow A shown in FIG.
FIG. 9B is a diagram illustrating the configuration of the light guide 25 and the reflecting member 70 as viewed from the direction of the arrow B illustrated in FIG. 5.

The reflecting member 70 of this embodiment is used when light incident from the incident surface 26 of the light guide 25 is diffused on the reflecting member 70 side. In addition, the same structure as 1st Embodiment among the reflective members 70 attaches | subjects the same code | symbol, and abbreviate | omits the description suitably.
The reflecting member 70 includes a reflecting portion 71 and a mounting portion 44, and the boundary between the reflecting portion 71 and the mounting portion 44 is bent at a right angle by a bent portion 45.
The reflection unit 71 reflects the light transmitted through the transmission surface 27 out of the light incident on the light guide 25 toward the emission surface 29. The reflection portion 71 is arranged in parallel to the transmission surface 27 of the light guide 25, and an uneven portion 72 that faces the transmission surface 27 is formed. The convex portion 73 of the concavo-convex portion 72 has the thickness of the conductive portion 75 by laminating a reflective layer 76 described later on a plurality of conductive portions 75 formed separately from the conductive portion 46 that supplies power to the LED chip 22. Formed due to The conduction part 75 of the present embodiment is a so-called dummy conduction part that does not have a function of transmitting a signal or the like. Each convex portion 73 is formed along the sub-scanning direction, like the conductive portion 75. Each convex portion 73 is in contact with the transmission surface 27 of the light guide 25. On the other hand, the concave portion 74 is formed between the convex portions 73 and does not contact the transmission surface 27 of the light guide 25. Since the convex portion 73 is in contact with the transmission surface 27 of the light guide body 25, the effect of reflecting the light transmitted through the transmission surface 27 out of the concave portion 74 toward the emission surface 29. Is expensive. Therefore, the uneven portion 72 is formed densely so that the interval becomes shorter as the distance from the incident surface 26 increases.
The convex portion 73 is not limited to being formed along the sub-scanning direction, and may be formed inclined with respect to the sub-scanning direction or may be formed in a dot shape.

(Third internal configuration)
Next, the third internal configuration of the reflection unit 71 will be specifically described. The third internal configuration is a configuration in which the light transmitted through the transmission surface 27 among the light incident on the light guide 25 is reflected by the reflective layer 76. In the third internal configuration, the thickness of the reflecting portion 71 is 50 μm to 508 μm, preferably 90 μm to 175 μm.
FIG. 10 is a cross-sectional view showing the internal configuration of the reflecting section 71 cut along the line II-II in FIG. 9A. The arrow U side shown in FIG. 10 is the side where the light guide 25 is disposed, and the arrow L side is the opposite side.
The reflection portion 71 is configured by laminating a reflection layer 76, a conduction portion 75 that is a metal wiring such as a copper foil, and a base film 64 as a base material from the U side.
The reflective layer 76 is laminated so as to cover the conductive portion 75. The reflection layer 76 reflects the light transmitted through the transmission surface 27 while diffusing the uneven portion 72. For the reflective layer 76, a white diffusion paint or a solder resist containing a white pigment can be used. Specifically, by including barium sulfate (BaSO 4) in the white diffusing paint, it is possible to reflect light having any emission wavelength of ultraviolet, visible and infrared. Further, by including magnesium fluoride-aluminum (MgF-Al) in the white diffusing paint, it is possible to reflect light having any emission wavelength of ultraviolet, visible and infrared. Further, by including titanium oxide (TiO) in the white pigment, light having visible and infrared emission wavelengths can be reflected. The thickness of the reflective layer 76 (T2 shown in FIG. 10) is preferably about the thickness of the conductive portion 75 plus about 10 μm so that the concave portion 74 and the convex portion 73 in the concave and convex portion 72 have different heights.
On the other hand, the base film 64 and the conductive portion 75 have the same configuration as the second internal configuration.

  According to the reflection part 71 having the third internal configuration, the light incident from the incident surface 26 of the light guide 25 is transmitted through the transmission surface 27 and irradiated toward the reflection part 71. The light irradiated to the reflection part 71 is diffused by the uneven part 72 and reflected by the reflection layer 76, and then enters the light guide 25 again through the transmission surface 27 of the light guide 25. The light incident on the light guide 25 again is emitted from the emission surface 29 of the light guide 25 and is applied to the document P.

In addition, as described above, the chemical component contained in the reflective layer 76 can reflect light having at least one of the emission wavelengths of ultraviolet, visible, and infrared. Therefore, the light irradiated toward the reflection part 71 can be reflected by the reflection layer 76 by changing the chemical component included in the reflection layer 76 according to the light having the emission wavelength emitted by the LED chip 22.
Further, in order to mount the LED package 21 on the mounting portion 44, it is preferable to mount the LED package 21 by removing a part of the reflective layer 76.
In the third internal configuration, when the rigidity can be maintained by the U-side protective film 66, or when the mounting portion 44 is omitted from the reflecting member 70, the metal sheet 65 and the L-side protective film 66 are omitted. be able to.

According to the present embodiment, as in the first embodiment, since the reflecting member 70 is in the form of a flexible sheet, it is lighter than a light guide cover formed by conventional injection molding. The apparatus and the image sensor unit 10 can be reduced in size.
In addition, since the uneven portion 72 due to the conductive portion 75 can be formed in the reflective layer 76 of the reflective member 70, the light irradiated to the reflective portion 71 is reflected by the reflective layer 76 while being diffused by the uneven portion 72. The Therefore, since it is not necessary to form the prism 28 in the light guide 25, the manufacturing cost of the light guide 25 can be reduced. At this time, the convex portions 73 are formed densely as the distance from the incident surface 26 increases. Accordingly, the light is diffused by the convex portion 73 as the position where the light is difficult to reach, so that the light guide 25 can emit light substantially uniformly along the main scanning direction of the emission surface 29.
Further, since the convex portion 73 of the reflection member 70 is in contact with the transmission surface 27 of the light guide 25, the reflection member 70 can be easily positioned by being sandwiched between the frame 12 and the light guide 25. it can.
The reflective layer 76 may be a retroreflecting material that refracts light using glass beads or the like.

<Third Embodiment>
In the second embodiment, the case where the uneven portion 72 is formed on the reflective layer 76 by laminating the reflective layer 76 on the dummy conductive portion 75 has been described. In this embodiment, the case where the uneven part 72 is formed in the reflective layer 76 by laminating the reflective layer 76 on the conducting part 46 that conducts the LED chip 22 will be described.
FIG. 11 is a diagram showing the configuration of the reflecting member 80 as seen from the direction of the arrow A shown in FIG. Note that, in the reflecting member 80, the same configurations as those of the second embodiment are denoted by the same reference numerals, and the description thereof is omitted as appropriate.

  As shown in FIG. 11, the conduction part 46 a of the conduction part 46 that conducts the LED chip 22 is formed in a meander shape over the entire surface of the reflection part 81. Further, the conductive portion 46a is formed so that the meander-shaped folded width (see W shown in FIG. 11) becomes shorter as the distance from the LED package 21 increases. Therefore, by forming the reflective layer 76 so as to cover the conductive portion 46a, the uneven portion 72 is formed in the reflective layer 76.

  According to the present embodiment, the concavo-convex portion 72 can be formed in the reflective layer 76 of the reflective portion 81 using the conductive portion 46a that conducts the LED chip 22, and thus the conductive portion 46a can be used effectively. . In addition, it is preferable that the conduction | electrical_connection part 46a formed in a meander shape is a conduction | electrical_connection part electrically connected by the electrode which forms ground among the electrodes of the LED package 21. FIG.

<Fourth Embodiment>
In the first to third embodiments, the case where the reflecting portions 41, 71, 81 of the reflecting members 40, 70, 80 are disposed facing only the transmission surface 27 has been described. In the present embodiment, a case where the reflection member 90 covers the reflection surface of the light guide 25 together with the transmission surface 27 will be described.
FIG. 12 is a view showing a reflecting member 90 according to the fourth embodiment.

In the reflecting member 90 of the present embodiment, a plurality of reflecting portions 91 face the transmitting surface 27 of the light guide 25 and a plurality of reflecting portions 91 are bent along the main scanning direction to be reflected on the reflecting surfaces 93, 94, 95 of the light guide 25. Arranged in contact. That is, as shown in FIG. 12, the reflection portion 91 of the light guide 25 is disposed so as to cover the reflection surfaces 93, 94, 95 and the transmission surface 27 of the light guide 25. Here, the reflecting portion 91 is positioned by being sandwiched between the frame 12 and the light guide 25.
In addition, a light shielding portion 92 is formed on the reflecting member 90 continuously to the reflecting portion 91. As shown in FIG. 12, the light shielding portion 92 covers a part of the emission surface 29 of the light guide body 25, and thereby can direct the light emission direction in a desired direction with high accuracy.

  According to the present embodiment, the light incident from the incident surface 26 of the light guide 25 can be reflected by the reflecting portion 91 that is in contact with the reflection surfaces 93, 94, 95 of the light guide 25, so that the frame 12 Inhaled light can be reduced. In addition, the structure of the reflection part 91 which touches the reflective surfaces 93, 94, and 95 of the light guide 25 reflects light without diffusing like the first internal structure and the second internal structure described above. It is preferable.

  As mentioned above, although this invention was demonstrated using embodiment mentioned above, this invention is not limited only to embodiment mentioned above, It changes within the range of this invention, or each embodiment is combined suitably. can do. In the above-described embodiment, the reflection members 40, 70, 80, and 90 have the mounting portion 44 via the curved portion 45 on only one side in the main scanning direction of the reflection portions 41, 71, 81, and 91. Although described, it is not limited to this case. For example, the reflection member 40, 70, 80, 90 may add the mounting part 44 via the curved part 45 on the other side in the longitudinal direction of the light guide 25. In this case, the LED package 21 is mounted on the added mounting portion 44 and is made to face the other end surface (incident surface) of the light guide 25 in the main scanning direction, so that the LED package is exposed from both end surfaces of the light guide 25. 21 light can be incident.

Further, in the above-described embodiment, the case where the LED package 21 is mounted on the mounting portion 44 has been described. However, the present invention is not limited to this case. 30 may be connected. In this case, the mounting portion 44 can be omitted from the reflecting members 40, 70, 80, 90.
In the above-described embodiment, the case where the image sensor unit driving motor 108 moves the image sensor unit 10 in the sub-scanning direction has been described. However, the document P is transported by a transport roller or the like without moving the image sensor unit 10. It may be.

  DESCRIPTION OF SYMBOLS 10: Image sensor unit 20: Light source 25: Light guide 26: Incident surface 27: Transmission surface (1st surface) 28: Diffusion part 29: Output surface 35: Condensing body 38: Image sensor 40: Reflective member 42: Flat Surface 46: Conductive part 52: Metal sheet 53: Permeable protective sheet (protective layer) 62: Reflective layer 65: Metal sheet 70: Reflective member 72: Concavity and convexity 73: Convex part 75: Conductive part 76: Reflective layer 80: Reflection Member 81: Reflection unit 90: Reflection member 91: Reflection unit 100: MFP (image reading apparatus, image forming apparatus) 102: Image reading unit 113: Image forming unit

Lighting apparatus of the present invention is an illumination device for irradiating a linear light to the illuminated body, a light source that Hassu light entrance surface through which light enters the light source is emitted to the inside, the inside from the incident surface A first surface that transmits a part of the incident light to the outside, and light reflected from the outside toward the first surface is emitted toward the object to be illuminated at a position facing the first surface. comprising a light guide rod-shaped having a second surface, and a reflecting member for light transmitted through the first surface at a position facing the front Symbol first surface is reflected toward the first surface, the said reflective member Is formed in a flexible sheet shape having a conducting portion, and the light source emits light by power feeding through the conducting portion .
The image sensor unit according to the present invention includes the illumination device, a light collector that forms an image of light reflected from the illumination object by the illumination device, and an electrical signal that is formed by the light collector. And an image sensor that converts the image sensor.
The image reading apparatus of the present invention includes: the image sensor unit; and an image reading unit that reads light from the illuminated body while relatively moving the image sensor unit and the illuminated body. Features.
The image forming apparatus of the present invention includes an image reading unit that reads light from the illuminated body while relatively moving the image sensor unit, the image sensor unit, and the illuminated body, and an image on a recording medium. And an image forming unit that forms the image.

Claims (16)

An illumination device for irradiating an object to be illuminated with line-shaped light,
A light source that emits light;
A first surface that is formed in a rod shape and transmits a part of light incident inside from the light source to the outside, and light reflected from the outside toward the first surface at a position facing the first surface. A light guide having a second surface that emits toward the illuminated body;
And a reflecting member that is formed in a flexible sheet shape and reflects light transmitted through the first surface at a position facing the first surface toward the first surface. apparatus.   The lighting device according to claim 1, wherein the reflection member has a conduction portion. The light guide has an incident surface on which light emitted from the light source is incident,
The reflective member is mounted with the light source, and the light source is arranged facing the incident surface by being partially bent,
The lighting device according to claim 2, wherein the light source emits light by power feeding through the conducting portion. The reflective member has a metal sheet,
4. The lighting device according to claim 1, wherein the metal sheet reflects light transmitted through the first surface toward the first surface. 5.   The lighting device according to claim 4, wherein the metal sheet is aluminum or an aluminum alloy.   The lighting device according to claim 4, wherein the reflection member has a protective layer that faces the first surface and transmits light having a light emission wavelength that is reflected by the metal sheet.   4. The reflection member according to claim 1, further comprising a reflection layer that faces the first surface and reflects light transmitted through the first surface toward the first surface. 5. The lighting device according to item. The reflective layer is formed with a flat surface facing the first surface,
The lighting device according to claim 7, wherein the first surface includes a diffusion unit that diffuses light when passing through the first surface. The reflection layer is formed on the conductive portion, so that a concavo-convex portion is formed on the surface facing the first surface,
The illumination device according to claim 7, wherein the uneven portion diffuses light transmitted through the first surface and reflects the light toward the first surface.   The lighting device according to claim 9, wherein the reflective member is arranged such that a convex portion of the concave and convex portions of the reflective layer is in contact with the first surface.   The lighting device according to claim 7, wherein the reflective layer is formed of a retroreflecting material.   The lighting device according to claim 7, wherein the reflective layer contains barium sulfate.   The lighting device according to claim 7, wherein the reflective layer includes titanium oxide. The lighting device according to any one of claims 1 to 13,
A condenser for imaging the light reflected by illuminating the object to be illuminated by the illumination device;
An image sensor unit comprising: an image sensor that converts light imaged by the light collector into an electrical signal. An image sensor unit according to claim 14,
An image reading apparatus comprising: an image reading unit that reads light from the illuminated body while relatively moving the image sensor unit and the illuminated body. An image sensor unit according to claim 14,
An image reading unit that reads light from the object to be illuminated while relatively moving the image sensor unit and the object to be illuminated;
An image forming apparatus comprising: an image forming unit that forms an image on a recording medium.

Images