JP2014095928A - Imaging apparatus and camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce size of a portion for driving a lens.SOLUTION: A lens barrel 102 comprises a step 151 and a step 152. A lens 23 is held in a part of the step 151, and a lens 21 and a lens 22 are held in a part of the step 152. A screw 111 is provided on the part of the step 152 and engaged with a screw 122 provided on a lens carrier 121. A coil 123 is wound around the lens carrier 121, and a magnet 124 is disposed in a position opposite to the coil 123. A voice coil motor is composed of the coil 123 and the magnet 124. The lens carrier 121 is configured to move with respect to a case 101. This invention can be applied to an actuator of an imaging apparatus.

Description

  The present invention relates to an image pickup apparatus, and more particularly to an image pickup apparatus that can realize downsizing of a portion having a function of driving a lens.

  FIG. 1 is a diagram illustrating a configuration of an example of a conventional imaging apparatus. The imaging apparatus 10 illustrated in FIG. 1 includes a case 11, a lens barrel 12, and an imaging element 13. The imaging device 10 is manufactured by incorporating the lens barrel 12 and the imaging element 13 into the case 11.

  A lens 21, a lens 22, and a lens 23 are incorporated inside the lens barrel 12, and the lens barrel 12 is configured to hold these lenses 21 to 23. A screw 24 is provided on the outer side surface of the lens barrel 12. The screw 24 and a screw (not shown) carved in a lens carrier 31 provided inside the case 11 are configured to be screwed together. The reason why the lens barrel 12 is screwed into the lens carrier 31 is to adjust the distance from the image pickup device 13 at the time of manufacture. After the focus is adjusted, the lens barrel 12 is fixed to the lens carrier 31 by bonding the lens barrel 12 and the lens carrier 31.

  Coils 32-1 and 32-2 are provided on the side surface of the lens carrier 31. For convenience of explanation, the coil 32-1 and the coil 32-2 are illustrated separately, but are provided as one coil 32 on the side surface of the lens carrier 31. A magnet 33-1 is provided inside the case 11 at a position facing the coil 32-1. Similarly, a magnet 33-2 is provided inside the case 11 at a position facing the coil 32-2. The magnet 33-1 and the magnet 33-2 are each provided with a yoke, which is not shown in FIG. The coil 32, the magnet 33, and the yoke constitute a voice coil motor.

  When a current is passed through the coil 32, a force is generated in the vertical direction in the figure. With this generated force, the lens carrier 31 moves upward or downward. As the lens carrier 31 moves, the lens barrel 12 fixed to the lens carrier 31 also moves. Therefore, the distance between the lenses 21 to 23 held by the lens barrel 12 and the image sensor 13 changes. With such a mechanism, auto focus (AF) is realized. (For example, see Patent Document 1)

JP 2007-17791 A

  In recent years, with the miniaturization of digital cameras and the spread of mobile phones having the functions of digital cameras, it is also desired to reduce the size of AF driving devices. Although it is possible to reduce the size of an AF driving device by reducing the size of an optical system such as a lens, an unfavorable state such as a reduction in the amount of light and a decrease in image quality is likely to occur. Therefore, it is not preferable to reduce the size of the driving device for AF by reducing the size of the lens or the like. However, as described above, further downsizing of the driving device (an imaging device including the driving device) is desired.

  With the configuration shown in FIG. 1, it is difficult to achieve further downsizing. Further, for example, if the lenses 21 to 23 are made smaller and the lens barrel 12 is made smaller with the configuration shown in FIG. 1, the image pickup apparatus can be reduced in size, but the image quality as described above is deteriorated. It is difficult to avoid this.

  Patent Document 1 describes an imaging apparatus that can reduce the size of the imaging apparatus when adopting a format in which a sector that blocks incident light on the lens is disposed on the subject side of the lens. The imaging apparatus described in Patent Document 1 includes a lens group including a plurality of lenses having different diameters, and a sector that blocks incident light to the lens group is disposed on the subject side of the lens group. The lens group is accommodated in a lens barrel, and the outer peripheral side wall of the lens barrel includes a step portion including a plurality of portions having different diameters respectively corresponding to the diameter of the lens accommodated therein, and around the step portion. Side wall recesses are formed. Sector driving means for driving the sector is arranged in the side wall recess.

  It is desired to further reduce the size of the imaging apparatus described in Patent Document 1. In addition, the imaging device described in Patent Document 1 has a structure in which, for example, the lens barrel does not have a screw mechanism, and cannot be adjusted with respect to the imaging element at the time of manufacture.

  In addition to the driving method described with reference to FIG. 1, a method of driving a lens has also been proposed. For example, a driving method using a piezoelectric element or a driving method using a shape memory alloy has been proposed, It is desirable to be able to apply these driving methods and to realize miniaturization of a portion related to driving.

  The present invention has been made in view of such a situation, and makes it possible to reduce the size of a portion that drives a lens.

  An imaging device according to one aspect of the present invention includes a first member that holds a lens, a second member to which the first member is fixed, and the second member that is perpendicular to the imaging surface of the imaging element. Drive means for driving in the direction, the first member has a different aperture, a portion having a small aperture is provided with a portion that engages with the second member, and the difference between the different apertures The drive means is provided in the resulting space.

  The first member may hold a plurality of lenses having different diameters and have a shape corresponding to the diameter of the lens.

  The drive means is a voice coil motor including a coil, a magnet, and a yoke, and the voice coil motor is provided in the space, and a side surface of the second member of the voice coil motor is provided on the side. The coil can be provided.

  The driving means includes a piezoelectric element, a shaft connected to the piezoelectric element, and a hook penetrating the shaft and connected to the second member, and the space includes the piezoelectric element and the shaft. The hook can be provided.

  The driving means includes a wire made of a shape memory alloy, a hook to which the wire is hooked, and an electrode connected to the wire, and the wire, the hook, and the electrode are provided in the space Can be made.

  In the imaging device of one aspect of the present invention, a screw for screwing with a member for driving the lens is provided at a portion of the aperture corresponding to the lens having the smallest aperture of the member for holding the lens, and the different apertures The drive means is provided in the space created to have the.

  According to one aspect of the present invention, it is possible to reduce the size of a portion that drives a lens.

It is a figure which shows the structure of an example of the conventional imaging device. It is a figure which shows the structure of one Embodiment of the imaging device to which this invention is applied. It is a figure for demonstrating the structure of an imaging device. It is a figure for demonstrating the magnitude | size of an imaging device. It is a figure which shows the structure of an example of the conventional imaging device for a comparison. It is a figure which shows the structure of other embodiment of the imaging device to which this invention is applied. It is a figure which shows the structure of an example of the conventional imaging device for a comparison. It is a figure which shows the structure of other embodiment of the imaging device to which this invention is applied.

  Embodiments of the present invention will be described below with reference to the drawings.

  The present invention can be applied to an imaging apparatus. Specifically, the imaging device is a device included in a digital still camera, a mobile phone having a digital still camera function, or the like. In such an image pickup apparatus, auto focus (AF: Auto-Focus) is realized by driving the lens (for example, moving in the perspective direction with respect to the image pickup element).

  An imaging apparatus including a driving device for realizing autofocus is configured as shown in FIG. 1, for example. Referring back to FIG. 1, the imaging device 10 includes a case 11 that houses a lens carrier 31. The lens carrier 31 is configured to be movable with respect to the case 11 in a vertical direction in the figure (a perspective direction with respect to the image sensor 13). Further, inside the lens carrier 31, a lens barrel 12 in which a plurality of lenses 21 to 23 are stored is mounted in a fixed state.

  The present embodiment described below mainly relates to a lens barrel and a lens carrier of the above-described imaging apparatus. An imaging device to which a lens barrel and a lens carrier to which the present embodiment described below is applied can be reduced in size compared to a conventional imaging device. Therefore, it is possible to reduce the size of a device including such a downsized imaging device, for example, a digital still camera or a mobile phone. In addition, it is possible to increase the space allocated to parts other than the imaging device, and it is possible to improve other functions.

  An imaging apparatus that can expect such an effect will be described below. As a method for realizing autofocus, a method using a voice coil motor (the method described with reference to FIG. 1), a method using a piezoelectric element, and a method using a wire made of a shape memory alloy have been proposed. Yes. Therefore, in the present embodiment described below, a mode in each method will be described. That is, as the first embodiment, when autofocusing is realized using a voice coil motor, as the second embodiment, when autofocusing is realized using a piezoelectric element, as the third embodiment, A case where autofocus is realized using a wire made of a shape memory alloy will be described as an example.

  In the following description, a member that holds a lens is referred to as a lens barrel, a member to which the lens barrel is fixed is referred to as a lens carrier, and a portion that drives the lens carrier is appropriately referred to as a driving device. Although the lens barrel has a cylindrical shape, it has a diameter that matches the diameter of the lens, so that the upper diameter (outer diameter) and the lower diameter (outer diameter) are different. A portion (screw) to be screwed with the lens carrier is provided in the lens barrel having a smaller diameter. Furthermore, since the caliber is different, a space is generated due to the difference in caliber. Driving means is provided in the generated space. As described above, this driving means differs for each of the first to third embodiments, and will be described below.

[About the first embodiment]
The first embodiment will be described below. FIG. 2 is a diagram illustrating a configuration example of the imaging apparatus 100 according to the first embodiment, and is a diagram illustrating a cross section of the imaging apparatus 100. The imaging apparatus 100 illustrated in FIG. 2 includes a case 101, a lens barrel 102, and an imaging element 103. The imaging device 100 shown in FIG. 2 is illustrated for each part as shown in FIG.

  Referring to FIG. 3, a lens 21, a lens 22, and a lens 23 are incorporated inside the lens barrel 102, and the lenses 21 to 23 are held. A screw 111 is provided on the outer side surface of the lens barrel 102.

  A lens carrier 121 is provided inside the case 101. A screw 122 is provided on the inner side (inner diameter) of the lens carrier 121. A coil 123 is provided on the outer (outer shape) side surface of the lens carrier 121. The coil 123 is configured to go around the side surface of the lens carrier 121. A magnet 124-1 and a magnet 124-2 are provided at predetermined positions on the inner side (inner diameter) of the case 101 at a position facing the coil 123, respectively. The magnets 124-1 and 124-2 are provided at opposing positions.

  The magnet 124-1 and the magnet 124-2 are each provided with a yoke. In FIGS. 2 and 3, the magnet and the yoke are shown together as a magnet 124-1 or a magnet 124-2. . Hereinafter, when it is not necessary to individually distinguish the magnets 124-1 and 124-2, they are simply referred to as magnets 124.

  The screw 111 of the lens barrel 102 and the screw 122 provided in the lens carrier 121 are configured to be screwed together. The reason why the lens barrel 102 is screwed into the lens carrier 121 is to adjust the distance from the image sensor 103 during manufacturing (to adjust the focus). After the focus is adjusted, the lens barrel 102 and the lens carrier 121 are bonded together, so that the lens barrel 102 is fixed to the lens carrier 121.

  In this way, when the lens barrel 102 is inserted into the case 101 and fixed to the lens carrier 121, the image sensor 103 is inserted into the case 101 and fixed to the case 101. In this manner, the lens barrel 102 and the image sensor 103 are sequentially attached to the case 101, whereby the image pickup apparatus 100 having the configuration shown in FIG. 2 is manufactured.

  In the imaging apparatus 100 having such a configuration, when a current is passed through the coil 123 provided in the lens carrier 121, a force is generated in the upward or downward direction in the figure depending on the direction of current flow in relation to the magnet 124. To do. With this generated force, the lens carrier 121 moves upward or downward. As the lens carrier 121 moves, the lens barrel 102 fixed to the lens carrier 121 also moves. Therefore, the distance between the lenses 21 to 23 held by the lens barrel 102 and the image sensor 103 changes. With such a mechanism, auto focus (AF) is realized.

The structure of the lens barrel 102 will be further described. Referring to FIG. 3, the lens barrel 102 has a stepped configuration, and the configuration shown in FIG. 3 has a two-step configuration. The stage 151 includes the lens 23, and the stage 152 includes the lens 21 and the lens 22. As shown in FIG. 3, the sizes of the lenses 21 to 23 satisfy the following relationship.
Lens 21 <Lens 22 <Lens 23

  Therefore, the step 151 including the lens 23 has a larger diameter (diameter) than the step 152 including the lens 21 and the lens 22. The aperture of the stage 151 is a slightly larger aperture than the aperture of the lens 23. Further, the diameter of the step 152 is slightly larger than the diameter of the lens 22 and smaller than the diameter of the lens 23.

  The stage 152 is provided with a screw 111. The screw 111 provided on the step 152 and the screw 122 provided on the lens carrier 121 are screwed together. The diameter of the lens carrier 121 is set to a diameter at which the screw 111 and the screw 122 are screwed together. Therefore, the diameter of the lens carrier 121 is set to be slightly larger than the diameter of the step 152.

  Further, the height of the step 152 is shorter than the height of the lens carrier 121. The height means a vertical direction (a perspective direction with respect to the image sensor) in FIG. When the lens barrel 102 is fixed to the lens carrier 121, the height of the lens carrier 121 is determined such that the step 151 of the lens barrel 102 does not come into contact with one end of the lens carrier 121.

  Here, the conventional imaging device 10 and the imaging device 100 in the first embodiment will be compared. The upper diagram of FIG. 4 shows the configuration of the conventional imaging apparatus 10 shown in FIG. 1, and the lower diagram of FIG. 4 shows the configuration of the imaging device 100 according to the first embodiment of the present invention shown in FIG. .

  Both the imaging device 10 and the imaging device 100 include lenses 21 to 23. Therefore, there is no difference between the imaging device 10 and the imaging device 100 in the optical system, and an image with the same image quality can be taken. In addition, the image pickup device 13 of the image pickup device 10 and the image pickup device 103 of the image pickup device 100 are both image pickup devices having the same number of pixels. Therefore, an image with the same image quality can be captured also in this respect.

  However, it can be seen that the imaging device 100 is smaller than the imaging device 10. This is because the lens barrel 102 of the imaging apparatus 100 is provided with a step, and the step 152 in which the small lens is accommodated is configured to have a smaller aperture than the step 151 in which the large lens is accommodated. This is because downsizing can be realized. Further, the difference between the stage 151 and the stage 152, specifically, the lens carrier 121, the screw 122, the coil 123, and the magnet 124 are accommodated in the difference between the aperture of the stage 151 and the aperture of the stage 152. This is because the downsizing of the imaging device 100 is realized.

  That is, the lens barrel 102 is shaped so that the aperture gradually decreases in accordance with the size of the lens to be stored, and the screw 111 is provided on the smaller aperture, and that portion is screwed into the lens carrier 121. In addition, it is possible to reduce the size of the imaging apparatus 100 by providing a driving device including the coil 123 and the magnet 124 on the side having a smaller diameter.

  In addition, “the lens barrel 102 is described as having a shape in which the aperture gradually decreases in accordance with the size of the lens to be stored”, but this “gradual decrease in aperture” is the following shape. Is included. That is, for example, as illustrated in FIG. 3, it includes a step shape such as a step 151 and a step 152. Although not shown, the number of stages is not two. For example, when three lenses are included, such as lenses 21 to 23 as shown in FIG. 3, three stages are provided corresponding to the number of lenses. Such a configuration is also included.

  In addition, although not illustrated, for example, a conical configuration (a part of a conical shape) in which the diameter gradually decreases continuously in a direction away from the imaging element 103 side instead of a step is also included. Further, for example, the side where the screw is provided (corresponding to the step 152 in FIG. 3) is cylindrical, and the side where the screw is not provided (corresponding to the step 151 in FIG. 3) is a part of the conical shape. Also included are combinations of shapes. Furthermore, shapes conceived from such shapes are also included.

  4, the lens carrier 31 is located outside the lens barrel 12, and the coil 32 and the magnet 33 are located outside the lens carrier 31. That is, in such a configuration, the aperture of the lens carrier 31 is larger than the aperture of the lens barrel 12, and the coil 32 and the magnet 33 are further located outside the lens carrier 31 having such a large aperture. The imaging device 10 itself becomes large.

  However, since the imaging apparatus 100 to which the first embodiment of the present invention shown in the lower diagram of FIG. 4 is applied has the above-described configuration, it is outside the lens barrel 102. The lens carrier 121 is located on the inner side of the largest diameter (outer diameter) portion. Further, a coil 123 and a magnet 124 are located outside the lens carrier 121 at a portion inside the outer diameter of the lens barrel 102. Accordingly, all or part of the lens carrier 121, the coil 123, and the magnet 124 are not located outside the outer diameter of the lens barrel 102, so that the imaging device 100 itself is downsized.

  In other words, the diameter of the lens barrel 102 on the imaging element 103 side is large, and the diameter on the opposite side is small. Thus, since the apertures of the lens barrel 102 are different, a space is created at the difference. By providing drive means (in this case, a coil 123, a magnet 124, and a yoke) for moving the lens carrier 121 in the vertical direction with respect to the imaging surface of the imaging element 103 in this space, the imaging apparatus 100 can be downsized. Is realized.

  Thus, by applying the present invention, it is possible to reduce the size of the imaging device. Further, even if the size is reduced, the image quality of the captured image does not deteriorate.

  The lens barrel 102 is screwed into the lens carrier 121 to perform focusing at the time of manufacture. This focusing can be performed by the same method as that of the conventional imaging device 10.

[Second Embodiment]
A second embodiment will be described below. The second embodiment is a case where autofocus is realized using a piezoelectric element. A piezoelectric element is a passive element using a piezoelectric effect that converts a force applied to a piezoelectric body into a voltage, or converts a voltage into a force, and is sometimes referred to as a piezoelectric element. In order to describe an imaging apparatus when performing autofocus using such a piezoelectric element, first, for comparison, the configuration of a conventional imaging apparatus is shown in FIG. 5A is a diagram when the imaging device 200 is viewed from the upper side, and FIG. 5B is a diagram (cross-sectional view) when the imaging device 200 is viewed from the side.

  The imaging apparatus 200 includes a case 201, a lens barrel 202, and an imaging element 203. The lens 21, the lens 22, and the lens 23 are incorporated inside the lens barrel 202, and the lens barrel 202 is configured to hold the lenses 21 to 23. A screw 211 is provided on the outer side surface of the lens barrel 202.

  A lens carrier 221 is provided inside the case 201. A screw 222 is provided on the inner side (inner diameter) of the lens carrier 221. A slide hook 223 is provided at a predetermined position on the outer (outer shape) side surface of the lens carrier 221. Of the both ends of the slide hook 223, one end is connected to the lens carrier 221, the other end is circular, and a circular hole is opened at the center. The shaft 224 is configured to pass through this hole.

  A piezoelectric element 225 is attached to the shaft 224, and the piezoelectric element 225 is fixed to the case 201. When a current is passed through the piezoelectric element 225, a force is generated and the slide hook 223 slides. When the slide hook 223 slides, the lens carrier 221 moves in the vertical direction with respect to the case 201 (in the perspective direction with respect to the image sensor 203), thereby realizing autofocus.

  In the conventional imaging apparatus 200 shown in FIG. 5, the lens carrier 221 is positioned outside the lens barrel 202, and the slide hook 223, the shaft 224, and the piezoelectric element 225 are positioned outside the lens carrier 221. That is, in the case of such a configuration, the aperture of the lens carrier 221 is larger than the aperture of the lens barrel 202, and the slide hook 223, the shaft 224, and the piezoelectric element 225 are further provided outside the lens carrier 221 having such a large aperture. Since it is located, the imaging device 200 itself becomes large.

  Therefore, the imaging apparatus according to the second embodiment to which the present invention is applied has a configuration as shown in FIG. 6 and realizes downsizing of the imaging apparatus. 6A is a diagram when the imaging device 250 is viewed from above, and FIG. 6B is a diagram (a cross-sectional view) when the imaging device 250 is viewed from the side.

  The imaging apparatus 250 shown in FIG. 6 has basically the same configuration as the conventional imaging apparatus 200 shown in FIG. The imaging apparatus 250 includes a case 251, a lens barrel 252, and an imaging element 253. The lens 21, the lens 22, and the lens 23 are incorporated inside the lens barrel 252, and the lens barrel 252 is configured to hold the lenses 21 to 23. A screw 261 is provided on the outer side surface of the lens barrel 252.

  A lens carrier 271 is provided inside the case 251. A screw 272 is provided on the inner side (inner diameter) of the lens carrier 271. A slide hook 273 is provided at a predetermined position on the outer (outer shape) side surface of the lens carrier 271. Of the both ends of the slide hook 273, one end is connected to the lens carrier 271 (integrated configuration), the other end is circular, and a circular hole is opened at the center. A shaft 274 is configured to pass through this hole.

  A piezoelectric element 275 is attached to the shaft 274, and the piezoelectric element 275 is fixed to the case 251. When a current is passed through the piezoelectric element 275, a force is generated, and the slide hook 273 slides. When the slide hook 273 slides, the lens carrier 271 moves in the vertical direction with respect to the case 251 (in the perspective direction with respect to the image sensor 253), thereby realizing autofocus.

The structure of the lens barrel 252 will be further described. Referring to FIG. 6B, the lens barrel 252 has a stepped configuration, and the configuration shown in FIG. 6 has a two-step configuration. The step 281 includes the lens 23, and the step 282 includes the lens 21 and the lens 22. As shown in FIG. 6, the sizes of the lenses 21 to 23 satisfy the following relationship.
Lens 21 <Lens 22 <Lens 23

  Therefore, the step 281 including the lens 23 has a larger diameter (diameter) than the step 282 including the lens 21 and the lens 22. The diameter of the step 281 is a slightly larger diameter than the diameter of the lens 23. Further, the diameter of the step 282 is slightly larger than the diameter of the lens 22 and smaller than the diameter of the lens 23.

  A screw 261 is provided on the step 282. The screw 261 provided on the step 282 and the screw 272 provided on the lens carrier 271 are screwed together. The diameter of the lens carrier 271 is set to a diameter at which the screw 261 and the screw 272 are screwed together. Therefore, the aperture of the lens carrier 271 is set to be slightly larger than the aperture of the step 282.

  Further, the height of the step 282 is shorter than the height of the lens carrier 271. The height means a vertical direction (a perspective direction with respect to the image sensor 253) in FIG. When the lens barrel 252 is fixed to the lens carrier 271, the height of the lens carrier 271 is determined such that the step 281 of the lens barrel 252 does not contact one end of the lens carrier 271.

  Here, the conventional imaging device 200 and the imaging device 250 in the second embodiment are compared. Both the imaging device 200 and the imaging device 250 include lenses 21 to 23. Therefore, there is no difference between the imaging device 200 and the imaging device 250 in the optical system, and an image with the same image quality can be taken. In addition, the image pickup device 203 of the image pickup device 200 and the image pickup device 253 of the image pickup device 250 are both image pickup devices having the same number of pixels. Therefore, an image with the same image quality can be captured also in this respect.

  However, it can be seen that the imaging device 250 is smaller than the imaging device 200. This is because the lens barrel 252 of the imaging device 250 is provided with a step, and the step 282 in which the small lens is accommodated is configured to have a smaller aperture than the step 281 in which the large lens is accommodated. This is because downsizing can be realized. Further, the difference between the step 281 and the step 282, specifically, the lens carrier 271, the slide hook 273, and a part or all of the shaft 274 are accommodated in the difference between the aperture of the step 281 and the aperture of the step 282. This is because downsizing of the imaging device 250 is realized by being configured.

  That is, the lens barrel 252 is shaped so that the aperture gradually decreases in accordance with the size of the lens to be stored, and a screw 261 is provided on the smaller aperture, and that portion is screwed into the lens carrier 271. By adopting a configuration and further including a drive device including the slide hook 273, the shaft 274, and the piezoelectric element 275 on the side having a smaller diameter, the imaging device 250 can be reduced in size.

  In addition, “the lens barrel 252 is described as a shape in which the aperture gradually decreases in accordance with the size of the lens to be stored”, but this “gradual decrease in aperture” refers to the following shape: Is included. That is, for example, as shown in FIG. 6, it includes a step shape such as a step 281 and a step 282. Although not shown, the number of stages is not two. For example, when three lenses are included, such as lenses 21 to 23 as shown in FIG. 6, three stages are provided corresponding to the number of lenses. Such a configuration is also included.

  In addition, although not shown in the drawings, a configuration of, for example, a conical shape (a part of a conical shape) in which the diameter gradually decreases continuously in a direction away from the imaging element 253 side instead of a step is also included. Further, for example, the side where the screw is provided (corresponding to the step 282 in FIG. 6) is cylindrical, and the side where the screw is not provided (corresponding to the step 281 in FIG. 6) is a part of the conical shape. Also included are combinations of shapes. Furthermore, shapes conceived from such shapes are also included.

  The conventional imaging device 200 shown in FIG. 5 has a structure that makes the imaging device 200 itself large as described above. However, since the imaging apparatus 250 to which the second embodiment of the present invention shown in FIG. 6 is applied has the above-described configuration, it is the outermost part of the lens barrel 252, but the most of the lens barrel 252. The lens carrier 271 is located in a portion inside the portion having a large aperture.

  Further, a part or all of the drive device including the slide hook 273, the shaft 274, and the piezoelectric element 275 located outside the lens carrier 271 are located inside the largest diameter portion (maximum outer diameter) of the lens barrel 252. Is located in the part. Therefore, the lens carrier 271, the slide hook 273, the shaft 274, and the piezoelectric element 275 are not all or partly located outside the maximum outer diameter of the lens barrel 252, so that the imaging device 250 itself is downsized. .

  In other words, the diameter of the lens barrel 252 on the image sensor 253 side is large, and the diameter on the opposite side is small. Since the apertures of the lens barrel 252 are thus different, a space is created at the difference. By providing driving means (in this case, the slide hook 273, the shaft 274, and the piezoelectric element 275) for moving the lens carrier 271 in the vertical direction with respect to the imaging surface of the imaging element 253 in this space, the imaging apparatus 250 is provided. Downsizing is realized.

  Thus, by applying the present invention, it is possible to reduce the size of the imaging device.

  The lens barrel 252 is screwed into the lens carrier 271 so that focusing is performed at the time of manufacture. This focusing can be performed by the same method as that of the conventional imaging apparatus 200.

  In the imaging apparatus 250 illustrated in FIG. 6, one set of the slide hook 273 and the shaft 274 is illustrated, but two to four sets may be provided. A pair of the slide hook and the shaft other than the pair of the slide hook 273 and the shaft 274 is provided to support the lens carrier 271 and a piezoelectric element is not attached. Even if the imaging device 250 includes a plurality of sets of slide hooks and shafts, the configuration of the imaging device 250 is not increased by the slide hooks and shafts, and downsizing can be realized.

[About the third embodiment]
A third embodiment will be described below. The third embodiment is a case where autofocus is realized using a wire of shape memory alloy. The shape memory alloy has a characteristic that its length becomes longer or shorter when a current is passed. In order to describe an imaging apparatus when performing autofocus using such a shape memory alloy wire, first, for comparison, the configuration of a conventional imaging apparatus is shown in FIG. FIG. 7A is a diagram when the imaging device 300 is viewed from above, and FIG. 7B is a diagram (cross-sectional view) when the imaging device 300 is viewed from the side.

  The imaging apparatus 300 includes a case 301, a lens barrel 302, and an imaging element 303. Inside the lens barrel 302, a lens 21, a lens 22, and a lens 23 are incorporated, and the lenses 21 to 23 are held. A screw 311 is provided on the outer side surface of the lens barrel 302.

  A lens carrier 321 is provided inside the case 301. A screw 322 is provided on the inner side (inner diameter) of the lens carrier 321. A hook 323-1 and a hook 323-2 are provided at predetermined positions on the outer (outer shape) side surface of the lens carrier 321. The hooks 323-1 and 323-2 are provided at positions facing each other with the lens carrier 321 interposed therebetween. The hook 323-1 and the hook 323-2 (hereinafter referred to simply as a hook 323 when there is no need to distinguish them individually) are also described as a wire 332 made of a shape memory alloy. Is locked.

  The wire 332 is also connected to the electrode 331-1 and the electrode 331-2. When current flows from the electrode 331-1 and the electrode 331-2 to the wire 332 and the temperature of the wire 332 increases, the length of the wire 332 made of the shape memory alloy decreases. When the length of the wire 332 is shortened, the hook 323 on which the wire 332 is hooked rises with respect to the case 301.

  Since the hook 323 is integrated with the lens carrier 321, when the hook 323 is raised with respect to the case 301, the lens carrier 321 is also raised with respect to the case 301. In this way, the lens carrier 321 is driven. Conversely, when the current flowing through the wire 332 is stopped, the temperature of the wire 332 decreases and the length of the wire 332 increases. When the length of the wire 332 is increased (returns to the original), the hook 323 is lowered and the lens carrier 321 is also lowered.

  A lens barrel 302 that holds a lens is fitted in the lens carrier 321. Therefore, by driving the lens carrier 321 in this way, the position of the held lens changes and the focal length is adjusted. That is, autofocus is realized.

  In the conventional imaging apparatus 300 shown in FIG. 7, a lens carrier 321 is located outside the lens barrel 302, and a hook 323, a wire 332, and an electrode 331 are located outside the lens carrier 321. That is, in such a configuration, the aperture of the lens carrier 321 is larger than the aperture of the lens barrel 302, and the hook 323, the wire 332, and the electrode 331 are further located outside the lens carrier 321 having such a large aperture. Therefore, the imaging device 300 itself becomes large.

  Therefore, the imaging apparatus according to the third embodiment to which the present invention is applied has a configuration as shown in FIG. 8 so that downsizing can be realized. 8A is a diagram when the imaging device 350 is viewed from above, and FIG. 8B is a diagram (a cross-sectional view) when the imaging device 350 is viewed from the side.

  The imaging device 350 shown in FIG. 8 has basically the same configuration as the conventional imaging device 300 shown in FIG. The imaging device 350 includes a case 351, a lens barrel 352, and an imaging element 353. Inside the lens barrel 352, a lens 21, a lens 22, and a lens 23 are incorporated, and the lenses 21 to 23 are held. A screw 361 is provided on the outer side surface of the lens barrel 352.

  A lens carrier 371 is provided inside the case 351. A screw 372 is provided on the inner side (inner diameter) of the lens carrier 371. A hook 373-1 and a hook 373-2 are provided at predetermined positions on the outer (outer shape) side surface of the lens carrier 371. The hook 373-1 and the hook 373-2 are provided at positions facing each other across the lens carrier 371. A wire 382 made of a shape memory alloy is hooked on the hooks 373-1 and 373-2.

  The wire 382 is also connected to the electrode 381-1 and the electrode 381-2. When current flows from the electrode 381-1 and the electrode 381-2 to the wire 382 and the temperature of the wire 382 increases, the length of the wire 382 made of the shape memory alloy decreases. When the length of the wire 382 is shortened, the hook 373 on which the wire 382 is hooked rises with respect to the case 351.

  Since the hook 373 is configured integrally with the lens carrier 371, when the hook 373 rises with respect to the case 351, the lens carrier 371 also rises with respect to the case 351. In this way, the lens carrier 371 is driven. Conversely, when the current flowing through the wire 382 is stopped, the temperature of the wire 382 decreases and the length of the wire 382 increases. When the length of the wire 382 is increased (returns to the original), the hook 373 is lowered and the lens carrier 371 is also lowered.

  A lens barrel 352 that holds a lens is fitted in the lens carrier 371. Therefore, by driving the lens carrier 371 in this way, the position of the held lens changes and the focal length is adjusted. That is, autofocus is realized.

The structure of the lens barrel 352 will be further described. Referring to FIG. 8B, the lens barrel 352 has a stepped structure, and the structure shown in FIG. 8 has a two-stage structure. The step 391 includes the lens 23, and the step 392 includes the lens 21 and the lens 22. As shown in FIG. 8, the sizes of the lenses 21 to 23 satisfy the following relationship.
Lens 21 <Lens 22 <Lens 23

  Therefore, the step 391 including the lens 23 has a larger diameter (diameter) than the step 392 including the lens 21 and the lens 22. The diameter of the step 391 is slightly larger than the diameter of the lens 23. Further, the diameter of the step 392 is slightly larger than the diameter of the lens 22 and smaller than the diameter of the lens 23.

  A screw 361 is provided on the step 392. The screw 361 provided on the step 392 and the screw 372 provided on the lens carrier 371 are screwed together. The diameter of the lens carrier 371 is a diameter at which the screw 361 and the screw 372 are screwed together. Therefore, the diameter of the lens carrier 371 is set to be slightly larger than the diameter of the step 392.

  Furthermore, the height of the step 392 is shorter than the height of the lens carrier 371. The height means a vertical direction (a perspective direction with respect to the image sensor 353) in FIG. When the lens barrel 352 is fixed to the lens carrier 371, the height of the lens carrier 371 is determined such that the step 391 of the lens barrel 352 does not contact one end of the lens carrier 371.

  The length of the hook 373 provided in the lens carrier 371 is such that a part of the tip of the lens barrel 352 protrudes outside the largest diameter (maximum outer diameter) of the lens barrel 352, or preferably the lens barrel 352 The length is set to the extent that the tip is accommodated inside the aperture.

  Here, the conventional imaging apparatus 300 (FIG. 7) and the imaging apparatus 350 (FIG. 8) in the third embodiment will be compared. Both the imaging device 300 and the imaging device 350 include lenses 21 to 23. Therefore, there is no difference between the imaging apparatus 300 and the imaging apparatus 350 in the optical system, and an image with the same image quality can be captured. In addition, the image pickup device 303 of the image pickup apparatus 300 and the image pickup device 353 of the image pickup apparatus 350 are both image pickup elements having the same size. Therefore, there is no difference in the number of pixels, and an image with the same image quality can be captured in this respect.

  However, it can be seen that the imaging device 350 is smaller than the imaging device 300. This is because the lens barrel 352 of the imaging device 350 is provided with a step, and the step 392 in which the small lens is accommodated is configured to have a smaller aperture than the step 391 in which the large lens is accommodated. This is because downsizing can be realized. Further, the difference between the step 391 and the step 392, more specifically, the lens carrier 371, the hook 373, and a part or all of the electrode 381 are included in the difference between the outer diameter of the step 391 and the outer diameter of the step 392. This is because the imaging device 350 can be downsized.

  That is, the lens barrel 352 is shaped so that the aperture gradually decreases in accordance with the size of the lens to be stored, and a screw 361 is provided on the smaller aperture, and that portion is screwed into the lens carrier 371. Further, the imaging device 350 can be reduced in size by including a driving device including the hook 373, the electrode 381, and the wire 382 on the side having a smaller diameter.

  In addition, “the lens barrel 352 is described as a shape in which the aperture gradually decreases in accordance with the size of the lens to be stored”, but this “gradual decrease in aperture” refers to the following shape: Is included. That is, for example, as shown in FIG. 8, it includes a step shape such as a step 391 and a step 392. Although not shown, the number of stages is not two. For example, when three lenses are included, such as lenses 21 to 23 as shown in FIG. 8, three stages are provided corresponding to the number of lenses. Such a configuration is also included.

  In addition, although not illustrated, for example, a conical configuration (a part of a conical shape) in which the diameter gradually decreases continuously in a direction away from the imaging element 353 side instead of a step is also included. Further, for example, the side where the screw is provided (corresponding to the step 392 in FIG. 8) is cylindrical, and the side where the screw is not provided (corresponding to the step 391 in FIG. 8) is a part of the conical shape. Also included are combinations of shapes. Furthermore, shapes conceived from such shapes are also included.

  The conventional imaging apparatus 300 shown in FIG. 7 has a structure in which the imaging apparatus 300 itself becomes large as described above. However, since the imaging apparatus 350 to which the third embodiment of the present invention shown in FIG. 8 is applied has the above-described configuration, it is the outermost part of the lens barrel 352. The lens carrier 371 is positioned in a portion inside the portion having a large aperture (outer diameter).

  Further, a part or all of the driving device including the hook 373, the electrode 381, and the wire 382 located outside the lens carrier 371 is located on the inner side of the lens barrel 352 having the largest aperture. . Therefore, since the lens carrier 371, the hook 373, the electrode 381, and the wire 382 are not all or partly located outside the largest diameter of the lens barrel 352, the imaging device 350 itself is downsized.

  In other words, the diameter of the lens barrel 352 on the image sensor 353 side is large, and the diameter on the opposite side is small. Since the apertures of the lens barrel 352 are thus different, a space is created at the difference. By providing driving means (in this case, the hook 373, the electrode 381, and the wire 382) for moving the lens carrier 371 in the vertical direction with respect to the imaging surface of the imaging device 353 in this space, the imaging device 350 can be reduced in size. Is realized.

  Thus, by applying the present invention, it is possible to reduce the size of the imaging device. In addition, when downsizing, the image quality of the captured image does not deteriorate.

  The lens barrel 352 is screwed into the lens carrier 371 so that focusing is performed at the time of manufacture. This focusing can be performed by the same method as that of the conventional imaging apparatus 300.

  In the imaging apparatus 350 shown in FIG. 8, two hooks 373 and two electrodes 381 and a wire 382 that is connected to them and circulates around the lens carrier 371 are shown, but one hook 373 and two electrodes 382 are illustrated. It is also possible to configure the electrodes 381 and the wires 382 that are connected to them and go around the lens carrier 371. That is, for example, the ends of the wires 382 are connected to the electrodes 381-1 and 381-2, respectively, and the hook 373-1 (or the hook 373-2) is positioned at the center of the wire 382. It is also possible.

  Even when configured in this way, the configuration of the imaging device 350 does not increase, and the size can be reduced.

  In the first to third embodiments described above, an example in which the lens closer to the image sensor is larger and the arranged lens becomes smaller in the direction away from the image sensor is taken as an example. I explained. However, the present invention is not limited to such a lens arrangement. That is, for example, the present invention can also be applied to an embodiment in which the lens far from the image sensor is large and the arranged lens is small in the direction approaching the image sensor.

  In the case of such a lens arrangement, a screw and a driving device are provided on the lens barrel where the small lens is arranged. Further, even when such a lens arrangement is used, it goes without saying that the size of the imaging device can be reduced as in the above-described embodiment.

  In the above-described embodiment, the image pickup apparatus provided with the three lenses 21 to 23 has been described as an example. However, the present invention is applicable to an image pickup apparatus provided with the three lenses. It is not meant to be limited. That is, the present invention can be applied to an imaging apparatus including a plurality of lenses.

  Thus, in the case where the lens is configured by a plurality of lenses and the diameter increases (or decreases) as the distance from the image sensor increases, the lens barrel that holds the plurality of lenses does not have a simple cylindrical shape. In accordance with the diameter, a stepped shape or a shape including a shape in which at least part of the diameter gradually decreases is used. The lens carrier that holds the lens barrel is also shaped to match the lens barrel, so that a sufficient space can be secured on the object side with respect to the inner wall of the module, and the actuator can be configured in this portion. Therefore, it is possible to make the lens module small.

  Further, in the conventional imaging apparatus having a structure in which the lens barrel and the lens carrier are not provided with the screw portion, focus adjustment cannot be performed with respect to the imaging element. In the present invention, the lens barrel and the lens carrier are provided with screw portions. As described above, by providing the lens barrel and the lens carrier with the threaded portion, it becomes possible to adjust the focus with respect to the image pickup device at the time of manufacture.

  When the present invention is used, it is not necessary to take an autofocus stroke more than necessary, and the requirement of characteristics for the actuator can be reduced. Further, since the stroke, that is, the movable range is small, power consumption is small.

  The embodiment of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

  101 cases, 102 lens barrels, 103 image sensors, 111 screws, 121 lens carriers, 122 screws, 123 coils, 124 magnets, 151, 152 stages, 251 cases, 252 lens barrels, 253 image sensors, 261 screws, 271 lens carriers, 272 screw, 273 slide hook, 274 axis, 275 piezoelectric element, 281, 282 stage, 351 case, 352 lens barrel, 353 image sensor, 361 screw, 371 lens carrier, 372 screw, 373 hook, 381 electrode, 382 wire, 391 , 392 stages

The present invention relates to an image pickup apparatus and a camera , and more particularly to an image pickup apparatus and a camera that can realize downsizing of a portion having a function of driving a lens.

An imaging device according to an aspect of the present technology includes a first member including a holding unit that holds a lens, a second member configured to surround the first member, the first member, and the lens. An image sensor disposed on the opposite side of the first element, and a drive unit that is disposed in a region adjacent to the first member and moves the first member in a direction perpendicular to the image sensor. The member includes at least a first portion and a second portion, wherein the first portion has a first outer diameter, and the second portion is a second smaller than the first outer diameter. The first part and the second part have a first corner and a second corner, respectively, and the first corner and the second corner are respectively first And at least a part of the drive part is disposed in a region corresponding to the second part.

The first cutout portion may include a chamfered edge.
  The second cutout portion may include a cut edge.
  The second member may be configured to surround the second portion, and the second member may be configured to be longer than the second portion in the vertical direction.
  The entire drive unit may be disposed in a region corresponding to the second part.

The inner surface of the first member may include a plurality of holding portions configured to hold a plurality of lenses, respectively.
  A first lens is disposed on the first portion of the first member, a second lens is disposed on the second portion of the first member, and the diameter of the first lens is It can be made larger than the diameter of the second lens.
  The first lens may be arranged closer to the image sensor than the second lens.
  A third lens is further disposed between the first lens and the second lens, and the diameter of the third lens is larger than the diameter of the second lens, It can be made smaller than the diameter.

  The drive unit may be a voice coil motor including a coil, a magnet, and a yoke.
  The drive unit may include a piezoelectric element, a shaft connected to the piezoelectric element, and a hook that penetrates the shaft and is connected to the second member.
  The drive unit may include a wire made of a shape memory alloy, a hook on which the wire is hooked, and an electrode connected to the wire.

  The outer surface of the second portion includes a first screw portion, the inner surface of the second member includes a second screw portion, and the first screw portion and the second screw portion are mutually connected. They can be screwed together.
  The inner diameter of the second member can be smaller than the second outer diameter of the first member.
  A camera according to one aspect of the present technology includes the imaging device.

In the imaging device according to one aspect of the present technology, the first member including the holding unit that holds the lens, the second member configured to surround the first member, and the first member and the lens opposite to each other An image sensor arranged on the side and a drive unit arranged in a region adjacent to the first member and moving the first member in a direction perpendicular to the image sensor are provided. The first member includes at least a first portion and a second portion, the first portion has a first outer diameter, and the second portion is a second smaller than the first outer diameter. The first portion and the second portion have a first corner and a second corner, respectively, and the first corner and the second corner each have a first cutout portion. And at least a part of the driving part is arranged in a region corresponding to the second part.
The camera according to one aspect of the present technology includes the imaging device.

Claims (5)

A first member holding the lens;
A second member to which the first member is fixed;
Driving means for driving the second member in a direction perpendicular to the imaging surface of the imaging element;
The first member has a different diameter, and a portion having a small diameter is provided with a portion that is screwed with the second member,
An imaging apparatus in which the driving unit is provided in a space generated by the difference in the different apertures. The imaging device according to claim 1, wherein the first member holds a plurality of lenses having different diameters and has a diameter corresponding to the diameter of the lenses. The driving means is a voice coil motor including a coil, a magnet, and a yoke,
In the space, the voice coil motor is provided,
The imaging device according to claim 1, wherein the coil is provided on a side surface of the second member of the voice coil motor. The driving means includes a piezoelectric element, a shaft connected to the piezoelectric element, and a hook penetrating the shaft and connected to the second member;
The imaging device according to claim 1, wherein the piezoelectric element, the shaft, and the hook are provided in the space. The driving means includes a wire made of a shape memory alloy, a hook on which the wire is hooked, and an electrode connected to the wire,
The imaging device according to claim 1, wherein the wire, the hook, and the electrode are provided in the space.

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