JP2006091264A - LENS DRIVE DEVICE, IMAGING DEVICE, AND OPTICAL DEVICE - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the size of an imaging apparatus for a small electronic device having an autofocus function at low cost.
SOLUTION: A ring member 24 is rotatably attached to an upper cover 20, and is normally locked by a tongue piece 24b and a pin 20b and is urged in the direction of arrow A by a spring 26 to be initial. Held in position. When the lens holder 14 is moved away from the CCD sensor, the lens holder 14 and the ring member 24 come into contact with each other, and the movement of the lens holder 14 is prevented. By this contact, the ring member 24 starts to rotate in the direction opposite to the arrow A against the spring 26, and the tongue piece 24 b passes over the photo interrupter 28. The photo interrupter 28 detects the passing tongue piece 24b and changes the output. By monitoring this change in output, it is detected that the lens holder 14 has moved to the front end position.
[Selection] Figure 3

Description

  The present invention relates to a lens driving device that moves a lens in a direction along an optical axis, and an imaging device and an optical device using the lens driving device.

  Small electronic devices such as mobile phones and PDAs (Personal Digital Assistants) that incorporate an imaging device that captures a subject and acquires digital image data have become widespread. Since these small electronic devices that are carried around on a daily basis are equipped with an imaging device, imaging can be easily performed at any time without having to carry a digital still camera or a digital video camera. In addition, these small electronic devices generally have a data communication function using infrared rays or the like in advance, and the captured image data is immediately transferred to other mobile phones or personal computers on the spot. There is also an advantage that it can be sent.

  On the other hand, an imaging device built in a small electronic device is considerably smaller than an ordinary digital still camera, and thus the size of components such as a lens and a CCD sensor is greatly limited. For this reason, the function for imaging and the image quality of the obtained image data are insufficient, and the current situation is that an imaging device incorporated in a small electronic device has not yet been used as a substitute device for a digital still camera.

  In order to overcome this situation, in recent years, high image quality has been rapidly promoted by the development of a small CCD sensor with a high pixel and a small lens with a high contrast. In addition, in order to enhance the imaging function, a small electronic device having an autofocus function that is normally installed in a digital still camera or the like has been announced.

  The autofocus function is realized by moving a lens in a direction along the optical axis (hereinafter referred to as an optical axis direction) within the imaging apparatus by a driving unit such as a motor or a piezoelectric element. The digital still camera's autofocus method can measure the distance to the subject using infrared rays, etc., and can move the lens to a position corresponding to that distance, or perform multiple imaging while moving the lens by a predetermined length. A contrast detection method is known in which a lens is moved to a position with the highest contrast.

  Further, inside the imaging apparatus, a photo interrupter or the like that detects that the lens has moved to the front end position (position where the lens and the CCD sensor are most separated) or the rear end position (position where the lens and the CCD sensor are closest) Detection means are provided. When performing autofocus processing, the lens is first moved to a position detected by the detection means, and autofocus processing is performed with this position as the initial position.

  In an imaging device built in a small electronic device, as well as improving image quality and enhancement of the imaging function, naturally downsizing is also an important issue. However, the detection means provided inside the imaging device is downsized. There was a problem of becoming an obstacle. In view of cost, it is common to use off-the-shelf products that can be obtained at low cost, and the development of small detection means in accordance with the downsizing of the imaging device will greatly increase the cost. Will lead to.

  The present invention has been made in view of the above problems, and is an imaging device for a small electronic device having an autofocus function, and a lens driving device that can be downsized at low cost, and this lens driving An object of the present invention is to provide an imaging apparatus and an optical apparatus using the apparatus.

  In order to solve the above problems, a lens driving device, an imaging device, and an optical device according to the present invention are incorporated coaxially inside a cylindrical stator that generates a magnetic field according to a flowed current, A cylindrical rotor that rotates by a magnetic field generated by the stator, and a cylindrical lens holder that is coaxially incorporated inside the rotor and holds the lens so that the rotation axis of the rotor and the optical axis coincide with each other. A cover that has an opening for exposing the lens and that covers the opening surface of the stator, and an elastic body that is rotatably provided in the opening of the cover and has one end fixed to the cover The ring member that is urged in a predetermined direction by the engagement with the cover and held in a predetermined position by the engagement with the cover, and the rotational movement of the rotor is directly applied in the optical axis direction. The rotation means comprises: conversion means for converting into motion and transmitting to the lens holder; and rotation restricting means formed such that a part of the ring member and a part of the lens holder are fitted together. And a moving mechanism for moving the lens holder in a state in which rotation is restricted in the optical axis direction, and the lens holder that rotates together with the rotor against the rotation restricting means when contacting the ring member Then, the ring member fitted by the rotation restricting means is rotated in a direction opposite to the urging force of the elastic body, and this rotation is detected by a rotation detecting means provided on the outer surface side of the cover. .

  The rotation restricting means is constituted by a straight key groove in the optical axis direction formed on a side surface of the lens holder and a key member fitted in the straight key groove provided in the ring member. preferable.

  Further, it is preferable that a reflection type optical sensor is used as the rotation detecting means, and the tongue piece protruding from the ring member is passed over the optical sensor and the rotation of the ring member is detected accordingly.

  In the lens driving device, the imaging device, and the optical device according to the present invention, when a ring member that is held in a predetermined position by the biasing of the elastic body is rotatably provided in the opening of the cover, the ring member is in contact with the ring member The lens holder that rotates with the rotor against the rotation restricting means rotates the ring member fitted by the rotation detecting means in the direction opposite to the biasing of the elastic body, and this rotation is provided on the outer surface side of the cover. By detecting with the detecting means, it is confirmed that the lens holder has moved to the moving end. Since the rotation detecting means is provided on the outer surface side of the housing, it is possible to reduce the size of the apparatus, and it is possible to easily use an off-the-shelf product for the rotation detecting means, which does not increase the cost. .

  1 and 2 are external perspective views of a front side and a back side of a camera-equipped mobile phone including an imaging apparatus to which the present invention is applied. The main body 102 of the camera-equipped mobile phone 100 includes an upper casing 111 and a lower casing 12, and a hinge section 113 that rotatably connects the casings 111 and 112.

  As shown in FIG. 2, the upper casing 111 is provided with an imaging device 10 to which the present invention is applied. The camera-equipped mobile phone 100 acquires image data from the imaging device 10. The hinge portion 13 is provided with a click mechanism (not shown) that locks the upper housing 111 and the lower housing 112 at a predetermined angle when the mobile phone 100 with a camera is used. The main body 102 is capable of unfolding and folding the upper housing 111 and the lower housing 112 by rotating around the hinge 113, and the upper housing when the camera-equipped mobile phone 100 is not used. 111 and the lower housing 112 are folded in parallel.

  Each of the casings 111 and 112 is formed in a substantially rectangular thin plate shape. The imaging device 10 is exposed from the back surface 111a of the upper housing 111, the LCD panel 126 and the reception speaker 127 are disposed on the front surface 111b, and the antenna 128 is disposed on the top surface 111c. An operation unit 131 and a transmission microphone 132 are provided on the front surface 112a of the lower housing 112, a socket 134 for connecting a cable with an external device such as a personal computer, and a card slot 136 in which a memory card is loaded. Are arranged.

  The antenna 128 receives a radio signal from another mobile phone or an Internet server and uses a radio signal transmitted from the camera-equipped mobile phone 100 to the outside when using a telephone call, an e-mail service, an Internet connection service, or the like. Send. The receiving speaker 127 outputs the voice or ringing tone of the communication partner. On the LCD panel 126, various information such as a menu screen and a telephone number of the called party, a through image obtained by the imaging device 10, an image recorded on a memory card, and the like are displayed. Further, the transmission microphone 132 converts the voice of the speaker into an electrical voice signal.

  The operation unit 131 includes a selection key 131a, a shutter button 131b, a dial key 131c, and the like. The selection key 131a is used for selecting / setting various menus. The camera-equipped cellular phone 100 can select an image pickup mode from various modes and pick up an image of a subject. Selection of these modes is performed by operating a selection key 131a. The selection key 131a is also used for a subject imaging operation by the imaging apparatus 10. The shutter button 131b is used for a release operation when the imaging device 10 performs imaging. The dial key 131c is operated when inputting a telephone number, e-mail text, or the like.

  FIG. 3 is an external perspective view schematically showing the configuration of the imaging apparatus 10. The imaging device 10 includes an imaging lens 12 that forms a subject image, a lens holder 14 that holds the imaging lens 12, a cylindrical stator 16 that moves the lens holder 14 that holds the imaging lens 12 in the optical axis direction, In addition, the upper cover 20 and the lower cover 22 provided so as to close the opening surface of the stator 16 include a cover 18 that sandwiches and fixes each part. An opening for exposing the imaging lens 12 is provided on the upper surface of the upper cover 20, and a ring member 24 is rotatably attached to the opening.

  The ring member 24 is urged in the direction of arrow A by a spring (elastic body) 26 hung on a pin 20a protruding from the upper surface of the upper cover 20 and a locking claw 24a protruding from the side surface of the ring member 24. Yes. The spring 26 is not limited to this, and may be rubber or the like as long as it can bias the ring member 24.

  A tongue piece 24b further protrudes from the side surface of the ring member 24. The tongue piece 24b and a pin 20b protruding from the upper surface of the upper cover 20 are in the direction of arrow A (corresponding to a predetermined direction in the claims). And is held at the initial position shown in FIG. 3 (corresponding to a predetermined position in the claims). A reflection type photo interrupter (rotation detecting means) 28 is provided at a position that is concentric with the tongue piece 24b and rotated in a direction opposite to the arrow A from the position where the ring member 24 is locked. ing.

  FIG. 4 is a cross-sectional view seen from the direction of arrow B (see FIG. 3) for schematically explaining the configuration of the imaging device 10. Inside the stator 16, a rotor 30 including a magnet 32 and a rotating body 34, a lens holder 14, and an imaging lens 12 are provided in order from the side closer to the inner surface of the stator 16. The lens holder 14 and the rotor 30 are formed in a cylindrical shape and are arranged coaxially with the stator 16. A low-pass filter 36 held by the lower cover 22 and a CCD sensor (solid-state imaging device) 38 are provided below the imaging lens 12. Of the above-mentioned configuration, the one not including the low-pass filter 36 and the CCD sensor 38 corresponds to the lens driving device described in the claims.

  The imaging lens 12 includes three lenses, a first lens 60, a second lens 62, and a third lens 64, in order from the side close to the upper cover 20. The subject light that has passed through the first lens 60, the second lens 62, and the third lens 64 is received by the CCD sensor 38 via the low-pass filter 36.

  The low-pass filter 36 averages an unnecessary minute spatial frequency component included in the subject light. By using the low-pass filter 36, problems such as pseudo colors and moire can be reduced.

  The CCD sensor 38 photoelectrically converts the subject light that has passed through the low-pass filter 36 to create image data corresponding to the subject light, and outputs this to the camera-equipped mobile phone 100.

  The stator 16 and the rotor 30 constitute a hollow claw pole type stepping motor. When a pulse current is applied to the stator 16, the rotor 30 rotates by a rotation angle corresponding to the number of pulses.

  FIG. 5 is an explanatory diagram schematically showing the configuration of the stator 16 and the magnet 32. The stator 16 is composed of two layers of coil parts, an upper coil part 16a and a lower coil part 16b. Since the upper coil portion 16a and the lower coil portion 16b have the same configuration, only the configuration of the upper coil portion 16a will be described below.

  The upper coil portion 16a is formed by being surrounded by a cylindrical shape with an upper coil cover 50 and a lower coil cover 52, and a coil 54 made of a conductive wire wound inside is surrounded by the covers 50 and 52. Has been. The upper coil cover 50 and the lower coil cover 52 are formed of a magnetic material such as iron, and teeth 50a and 52a are provided on the inner side of the cylindrical shape so as to engage with each other alternately. A gap is provided between the teeth 50a and the teeth 52a.

  A pulse current is alternately supplied to the coil 54 of the upper coil portion 16a and the coil 54 of the lower coil portion 16b. When a pulse current is applied, concentric magnetic field lines centered on the current are generated in the coil 54 (so-called right-handed screw law). The generated lines of magnetic force try to pass through the inside of the upper coil cover 50 or the lower coil cover 52, which is a magnetic material, and are temporarily released into the air when reaching the teeth 50a or 52a. The released magnetic field lines cross the gap and enter the upper coil cover 50 or the lower coil cover 52 again. As a result, the side where the magnetic lines of force of the teeth 50a and 52a arranged so as to mesh with each other become the N pole, and the side where the magnetic lines of force again enter becomes the S pole, and the N pole and S pole along the cylindrical inner periphery of the stator 16 Magnetic fields are alternately formed.

  For example, the magnet 32 passes through the inside of a ring-shaped head in which N poles and S poles are alternately formed along the inner circumference, so that the N poles and S poles are alternately arranged along the cylindrical outer circumference. It is a permanent magnet with a magnetic pole, and rotates due to repulsive force and attractive force with the magnetic field formed by the stator 16.

  Further, the magnet 32 is formed into 48 poles, and 48 teeth 50a and 52a of the upper coil portion 16a and the lower coil portion 16b are provided, respectively. Further, the positions of the teeth 50a and 52a of the upper coil portion 16a and the positions of the teeth 50a and 52a of the lower coil portion 16b are shifted by half a tooth.

  FIG. 6 is an explanatory diagram showing a procedure for rotating the magnet 32 in the forward direction. Note that the rotation direction of the magnet 32 and the direction of the pulse current flowing through the stator 16 are both forward in the clockwise direction and reverse in the counterclockwise direction (see FIG. 5).

  When rotating the magnet 32 in the forward direction, first, as shown in FIG. 6A, a forward pulse current is applied to the upper coil portion 16a. The upper coil portion 16 a to which the forward pulse current is applied has the teeth 50 a as N poles and the teeth 52 a as S poles, and attracts each of the magnetic poles forming a pair of magnets 32.

  Next, as shown in FIG. 6B, a forward pulse current is applied to the lower coil portion 16b. Since the positions of the teeth 50a and 52a of the upper coil portion 16a and the positions of the teeth 50a and 52a of the lower coil portion 16b are shifted by half of the teeth, the teeth 50a and 52a of the lower coil portion 16b having a magnetic pole are shifted. As attracted to each, the magnet 32 rotates in the forward direction by half a tooth. Similarly, a reverse pulse current is applied to the upper coil portion 16a, a reverse pulse current is applied to the lower coil portion 16b, and the process returns to the procedure of FIG. Rotate forward.

  On the other hand, when rotating the magnet 32 in the reverse direction, as shown in FIG. 7, a forward pulse current is applied to the upper coil portion 16a, and a reverse pulse current is applied to the lower coil portion 16b. The magnet 32 rotates in the reverse direction by repeating energization in the order of energizing the pulse current in the reverse direction to 16a and energizing the lower coil portion 16b in the forward direction.

  As described above, by alternately energizing the upper coil portion 16a and the lower coil portion 16b, the half coil is rotated by one pulse, and each of the upper coil portion 16a and the lower coil portion 16b has 48 pulses, for a total of 96 pulses. By doing so, the magnet 32 rotates once.

  As shown in FIG. 4, the rotating body 34 is bonded to the inside of the magnet 32 and rotates as the magnet 32 rotates. A spiral groove 34 a is formed on the inner surface of the rotating body 34, and the spiral groove 34 a meshes with a spiral mountain 14 a formed on the outer surface of the lens holder 14. That is, the spiral groove 34a and the spiral mountain 14a constitute a so-called helicoid that converts the rotational force of the rotating body 34 into a linear motion in the direction of the optical axis, and is an example of the conversion means described in the claims.

  Further, a rectilinear key groove 14 c formed in the optical axis direction is provided on the side surface of the lens holder 14. The ring member 24 attached to the upper cover 20 is formed with a cylindrical portion 24c that protrudes inward in the vicinity of the inner periphery, and a key member 24d that fits the straight key groove 14c is provided in the cylindrical portion 24c. . The rectilinear keyway 14c and the key member 24d are so-called rectilinear keys, and show an example of the rotation restricting means described in the claims. It should be noted that the relationship between the groove and the key may be reversed, and the groove may be provided in the ring member 24 and the key may be provided in the lens holder 14.

  The spiral groove 34a of the rotator 34 is formed two more times than the spiral crest 14a of the lens holder 14, and the linear movement in the optical axis direction is performed in a state where the rotation is restricted by the straight key groove 14c and the key member 24d. By transmitting the converted force to the lens holder 14, the lens holder 14 moves in the optical axis direction. In the present embodiment, when the rotor 30 rotates in the forward direction, the lens holder 14 moves in a direction away from the CCD sensor 38 (hereinafter referred to as the front direction), and when the rotor 30 rotates in the reverse direction. It is assumed that the lens holder 14 and the CCD sensor 38 move in a direction (hereinafter referred to as a rear surface direction). However, the relationship between the rotation direction of the rotor 30 and the movement direction of the lens holder 14 may be reversed.

  Further, the moving distance of the lens holder 14 depends on the pitch between the spiral groove 34a and the spiral mountain 14a, and the rotator 34 makes a full stroke movement by rotating twice. Since the rotating body 34 makes one cycle by energizing the stator 16 with 96 pulses, it has a resolution of 192 pulses, and the moving distance of the lens holder 14 is controlled by the number of energized pulse currents. be able to.

  Further, a stepped portion 14 b having a different outer diameter is formed on the side surface of the lens holder 14. As the lens holder 14 moves in the front direction, the stepped portion 14b and the cylindrical portion 24c come into contact with each other, and the ring member 24 prevents the lens holder 14 from moving in the front direction. Therefore, the position where the stepped portion 14b and the cylindrical portion 24c contact each other is the front end position where the imaging lens 12 and the CCD sensor 38 are farthest from each other.

  As described above, the ring member 24 is pivotally attached to the upper cover 20, and is normally locked by the tongue piece 24b and the pin 20b, and in the direction of arrow A (reverse direction) by the spring 26. Energized and held in the initial position. If the lens holder 14 is further moved in the front direction while the stepped portion 14b and the cylindrical portion 24c are in contact with each other, friction is generated in each portion such as the spiral groove 34a and the spiral mountain 14a, against the straight key. The lens holder 14 starts to rotate with the rotor 30. The rotated lens holder 14 rotates the ring member 24 fitted by the straight advance key in a direction (forward direction) opposite to the bias of the spring 26. The lens holder 14 may start rotating together with the rotor 30 by contacting the end of the spiral crest 14a with a stopper (not shown) provided in the spiral groove 34a or the end of the spiral groove 34a.

  When the ring member 24 rotates in the forward direction, the tongue piece 24b passes over the photo interrupter 28 that is concentric. The photo interrupter 28 detects the passing tongue piece 24b and changes the output. Therefore, by monitoring the output of the photo interrupter 28, it can be determined whether or not the lens holder 14 is at the front end position.

  FIG. 8 is a block diagram showing the configuration of the camera-equipped mobile phone 100 necessary for explaining the present invention.

  The image data output from the CCD sensor 38 is input to the image processing circuit 174. The image processing circuit 174 is a so-called analog front end circuit, converts analog image data into digital image data, adjusts image quality such as brightness level correction and white balance correction to the image data, YC processing, A fixed length process and a compression process are performed.

  When a through image is displayed on the LCD panel 126 during shooting, the image data whose image quality has been adjusted is subjected to a simple level of simple YC processing and converted to simple YC image data composed of luminance data and color difference data. The simple YC image data is read to the display circuit 177 via the image memory 176, converted into a composite signal such as NTSC, and input to the LCD panel 126.

  When shooting is performed, the image processing circuit 174 performs full-scale YC processing on the image data that has undergone image quality adjustment, and generates YC image data. The YC image data is further subjected to fixed length processing and compression processing, and is converted into compressed image data such as JPEG format, for example. The compressed image data is stored in a RAM 170b, which will be described later, and then written to the memory card 200 via the card slot 136.

  The AF evaluation value calculation circuit 180 calculates an AF evaluation value from the contrast of image data for one screen generated by the image processing circuit 174. In general, the contrast of the image is highest when the subject image is in focus, and the AF evaluation value is also highest at this time. The AF evaluation value is input to the system controller 170 as an AF evaluation value signal.

  The system controller 170 controls the entire mobile phone 100 with a camera. The system controller 170 includes, for example, a microcomputer, and includes, in addition to the CPU, a ROM 170a that stores a control program and various setting data, and a RAM 170b that stores various data generated during control.

  The system controller 170 controls the movement of the lens holder 14 by supplying a pulse current to the stator 16 via the stator driver 160. Further, the output of the photo interrupter 28 is connected to the system controller 170. When moving the lens holder 14, the system controller 170 monitors the output of the photo interrupter 28 and determines whether or not the lens holder 14 is at the front end position.

  Next, the operation of the imaging device 10 and the camera-equipped mobile phone 100 configured as described above will be described with reference to the flowchart shown in FIG.

  When an imaging mode is selected by operating the selection key 131a, or when auto-focus is instructed to the system controller 170 by a half-pressing operation of the shutter button 131b, the system controller 170 first starts the stator via the stator driver 160. A pulse current is applied to 16 and the lens holder 14 is moved in the front direction.

  At the same time, the system controller 170 monitors the output of the photo interrupter 28, detects that the lens holder 14 has moved to the front end position, and then stops energization of the pulse current to the stator 16.

  When the system controller 170 stops the lens holder 14 at the front end position, the system controller 170 performs imaging once for calculating the AF evaluation value. The image data thus obtained is sent to the AF evaluation value calculation circuit 180 via the image processing circuit 174. The AF evaluation value calculation circuit 180 calculates an AF evaluation value from the image data and records it in the RAM 170b of the system controller 170.

  When the AF evaluation value at the front end position is recorded in the RAM 170b, the system controller 170 energizes the stator 16 with a predetermined number of pulse currents, and moves the lens holder 14 in the rear surface direction by a distance corresponding to the number of pulse currents. After the movement, imaging for calculating the AF evaluation value is performed again. Thereafter, this procedure is repeated until the rear end position. The rear end position may be detected by the number of pulses from the front end position, or may be detected by a separately provided sensor or switch.

  Thereby, a plurality of AF evaluation values with a predetermined interval can be obtained from the front end position to the rear end position. Since the position with the highest AF evaluation value can be regarded as the focus position, autofocus is completed by selecting the highest AF evaluation value from the obtained AF evaluation values and moving the lens holder 14 to that position. To do.

  As described above, in the imaging device 10 according to the present embodiment, the ring holder 24 rotates against the spring 26 when the lens holder 14 that has moved in the front surface direction and the ring member 24 come into contact with each other. By detecting with the interrupter 28, it is detected that the lens holder 14 is in the front end position. Since the photo interrupter 28 is attached to the outer surface side of the cover 18, the interior can be opened by the amount of the photo interrupter 28, and the structure of the lens holder 14, the rotor 30, and the like can be simplified. Therefore, the size of the apparatus can be reduced as compared with the conventional imaging apparatus in which the position of the lens holder 14 is detected by the detecting means provided inside.

  In the above embodiment, the reflection type photo interrupter 28 is used as the rotation detecting means. However, the present invention is not limited to this. For example, other types of optical sensors such as a transmission type photo interrupter may be used. Furthermore, a magnetic sensor such as a Hall element may be used, or a mechanical contact such as a microswitch may be used.

  Moreover, in the said embodiment, although the conversion means is comprised by the helicoid by the spiral groove 34a and the spiral mountain 14a, it is not restricted to this, For example, a cam groove is provided in the inner surface of the rotary body 34, and this cam groove is provided in this cam groove. The conversion means may be configured by a cam mechanism in which a cam pin to be fitted is provided on the outer surface of the lens holder 14.

  In this way, various known detection means can be applied, and no specially complicated mechanism is required, so that downsizing can be performed at low cost.

  In the above-described embodiment, the CCD sensor 38 is used as the solid-state imaging device. However, the present invention is not limited to this, and other types of solid-state imaging devices such as a CMOS image sensor may be used.

  Further, the pin 20a, the photo interrupter 28, and the like may be provided on the camera-equipped mobile phone 100 side to further reduce the size of the imaging device 10.

  Further, in the above embodiment, the contrast detection method is used as the autofocus method, but the present invention is not limited to this, and can be applied to other methods such as an active method.

  As described above, the example in which the present invention is applied to the digital camera built in the camera-equipped mobile phone has been described. However, the present invention is not limited to this, and the subject image is printed on the photographic film to record the image. The present invention can also be applied to a so-called silver lead camera. Furthermore, the present invention can be widely applied to optical devices other than cameras, such as a projection device such as a projector, and a pickup lens device used when reading data recorded on a CD-ROM, DVD, or the like. .

It is the perspective view which showed the external appearance of the front side of the mobile phone with a camera. It is the perspective view which showed the external appearance of the back side of the mobile phone with a camera. 1 is an external perspective view schematically illustrating a configuration of an imaging apparatus. It is sectional drawing which illustrates the structure of an imaging device roughly. It is a perspective view explaining the composition of a stator and a magnet roughly. It is explanatory drawing which shows the procedure at the time of rotating a magnet to a forward direction. It is explanatory drawing which shows the procedure at the time of rotating a magnet to a reverse direction. It is a block diagram which shows roughly the internal structure of the mobile phone with a camera. It is a flowchart which shows the procedure of the autofocus of the mobile phone with a camera.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Imaging device 14 Lens holder 14a Spiral mountain (conversion means)
14c Straight keyway (rotation restricting means)
16 Stator 18 Cover 24 Ring member 24b Tongue piece 24d Key member (rotation restricting means)
26 Spring (elastic body)
28 Photointerrupter (Rotation detection means)
30 rotor 34a spiral groove (conversion means)
38 CCD sensor (solid-state image sensor)

Claims (7)

A cylindrical stator that generates a magnetic field in accordance with the flowed current;
A cylindrical rotor that is coaxially incorporated inside the stator and is rotated by a magnetic field generated by the stator, and
A cylindrical lens holder that is coaxially incorporated inside the rotor and holds the lens so that the rotation axis of the rotor coincides with the optical axis;
A cover having an opening for exposing the lens and provided so as to close the opening surface of the stator;
A ring member that is rotatably provided in the opening of the cover and is biased in a predetermined direction by an elastic body fixed to the cover, and held in a predetermined position by being engaged with the cover. When,
Rotation formed by fitting a converting means for converting the rotational motion of the rotor into a linear motion in the direction of the optical axis and transmitting it to the lens holder, and a part of the ring member and a part of the lens holder fit together. A lens driving device comprising: a movement mechanism configured to move the lens holder in a state in which the rotation in the optical axis direction is restricted according to the rotation of the rotor;
In the lens holder that rotates together with the rotor against the rotation restricting means when contacting the ring member, the ring member fitted by the rotation restricting means is moved in a direction opposite to the biasing of the elastic body. A lens driving device characterized in that the rotation is detected by rotation detection means provided on the outer surface side of the cover.   The rotation restricting means is constituted by a linear key groove in an optical axis direction formed on a side surface of the lens holder, and a key member fitted in the linear key groove provided in the ring member. The lens driving device according to claim 1.   The rotation detecting means is a reflection type optical sensor, and detects the rotation of the ring member in response to a tongue protruding from the ring member passing over the optical sensor. The lens driving device according to claim 1 or 2. A cylindrical stator that generates a magnetic field in accordance with the flowed current;
A cylindrical rotor that is coaxially incorporated inside the stator and is rotated by a magnetic field generated by the stator, and
A cylindrical lens holder that is coaxially incorporated inside the rotor and holds the lens so that the rotation axis of the rotor coincides with the optical axis;
A cover having an opening for exposing the lens and provided so as to close the opening surface of the stator;
A ring member that is rotatably provided in the opening of the cover and is biased in a predetermined direction by an elastic body fixed to the cover, and held in a predetermined position by being engaged with the cover. When,
Rotation formed by fitting a converting means for converting the rotational motion of the rotor into a linear motion in the direction of the optical axis and transmitting it to the lens holder, and a part of the ring member and a part of the lens holder fit together. A moving mechanism configured to move the lens holder in a state in which the rotation in the optical axis direction is restricted according to the rotation of the rotor;
In an imaging apparatus comprising: a solid-state imaging device that photoelectrically converts subject light imaged by the lens and creates image data according to the subject light;
In the lens holder that rotates with the rotor against the rotation restricting means when coming into contact with the ring member, the ring member fitted by the rotation restricting means is placed in a direction opposite to the biasing of the elastic body. An imaging apparatus, wherein the imaging device is rotated, and the rotation is detected by a rotation detecting means provided on the outer surface side of the cover.   The rotation restricting means is constituted by a linear key groove in an optical axis direction formed on a side surface of the lens holder, and a key member fitted in the linear key groove provided in the ring member. The imaging device according to claim 4.   The rotation detecting means is a reflection type optical sensor, and detects the rotation of the ring member in response to a tongue protruding from the ring member passing over the optical sensor. The imaging device according to claim 4 or 5. An optical device comprising the lens driving device according to claim 1.

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