Imaging apparatus

Abstract

To provide a heat radiation configuration that sufficiently cools heat from an image pick-up device, and does not inhibit drive control of a movable part.SOLUTION: An imaging apparatus comprises an image pick-up device. A heat radiation member has at least a plurality of first cylindrical members arranged so that the central axes are orthogonal to a first direction, and a plurality of second cylindrical members arranged so that the central axes are orthogonal to a second direction. A first surface on which the plurality of first cylindrical members rotate and move in the first direction, and a second surface on which the plurality of second cylindrical members rotate and move in the second direction, are arranged stacked in an optical axis direction.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to an imaging device equipped with a heat dissipation structure. [Background technology]

[0002] 2. Description of the Related Art Imaging devices such as digital still cameras and video cameras are equipped with imaging elements such as CMOS sensors and CCD sensors for capturing subject images, as well as electronic elements such as CPUs and ICs mounted on circuit boards, which generate heat.

[0003] If the temperature of the imaging element or electronic elements rises excessively, their performance may deteriorate or they may malfunction, making it impossible to take good images.

[0004] Patent Document 1 discloses a device that efficiently dissipates heat by bringing a heat dissipation member provided inside the device into contact with a plurality of spheres.

[0005] Moreover, Patent Document 2 discloses a device that efficiently dissipates heat while deforming a number of fixed cylindrical members. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2009-272789 [Patent Document 2] Patent Publication No. 2009-284414 Summary of the Invention [Problem to be solved by the invention]

[0007] 2. Description of the Related Art In recent years, imaging devices that perform blur correction by moving an imaging element in a direction perpendicular to the optical axis direction to improve image quality have become widespread.

[0008] Even in such image capture devices that perform shake correction, sufficient heat dissipation is required because heat generated in the image capture element when the shake correction mechanism is operating, when continuous shooting is performed, or when video is captured affects image quality.

[0009] However, the device disclosed in Patent Document 1 has a problem in that the contact area is smaller than that of a line contact or surface contact configuration because the contact portions are point contact, resulting in lower heat dissipation efficiency.

[0010] Furthermore, the device disclosed in Patent Document 2 is configured to significantly deform the elastic member in order to increase the contact area with the movable and fixed parts, and there is a problem in that when the movable part moves, a large driving resistance is generated due to the deformation force of the elastic member.

[0011] The present invention has been made in consideration of the above problems, and an object of an embodiment of the present invention is to provide a heat dissipation configuration that sufficiently cools heat from the imaging element while not impeding drive control of the movable part. [Means for solving the problem]

[0012] An imaging device according to one aspect of the present invention includes an imaging element, a movable portion on which the imaging element is mounted and which is movable in a first direction perpendicular to an optical axis and a second direction perpendicular to the first direction and the optical axis, a holding portion which holds the movable portion, and a heat dissipation member sandwiched between the movable portion and the holding portion in the optical axis direction, the heat dissipation member has at least a plurality of first cylindrical members arranged such that their central axes are perpendicular to the first direction, and a plurality of second cylindrical members arranged such that their central axes are perpendicular to the second direction, The present invention is characterized in that a first surface along which the plurality of first cylindrical members rotate in the first direction and a second surface along which the plurality of second cylindrical members rotate in the second direction are stacked and arranged in the optical axis direction. Effect of the Invention

[0013] According to one embodiment of the present invention, it is possible to provide a heat dissipation structure that can sufficiently cool heat from an imaging element without impeding drive control of a movable part. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a block diagram showing a configuration of a digital camera according to a first embodiment. [Diagram 2] FIG. 1 is an exploded perspective view of a digital camera according to a first embodiment. [Diagram 3] FIG. 2 is an exploded perspective view of the main part of the digital camera according to the first embodiment. [Figure 4] FIG. 2 is a cross-sectional view of the main part of the digital camera according to the first embodiment. [Diagram 5] FIG. 2 is a perspective view of a heat dissipation member of the digital camera according to the first embodiment. [Figure 6] FIG. 2 is a front view of the main part of the digital camera according to the first embodiment. [Figure 7] FIG. 11 is a cross-sectional view of a main part of a digital camera according to a first modified example. [Figure 8] FIG. 13 is a perspective view of a heat dissipation member of a digital camera according to a first modified example. [Figure 9] FIG. 2 is a diagram showing the relationship between the ball 119, the first cylindrical member 201, and the flat plate 203. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, embodiments of the present invention will be described with reference to the drawings. EXAMPLES

[0016] (Block diagram of digital camera 100) FIG. 1 shows the configuration of a digital camera (hereinafter simply called a camera) 100 as an image capturing apparatus according to a first embodiment of the present invention.

[0017] A detachable (replaceable) lens unit 500 including a lens 501 is attached to the camera 100. For simplification, only one lens 501 is shown in the figure, but in reality, a plurality of lenses are provided.

[0018] In the camera 100, the shutter 108 is a focal plane shutter that controls the exposure time of an image sensor 115, which will be described later, and its operation is controlled by a camera system control unit 150, which will be described later.

[0019] The image sensor 115 is configured with a CCD sensor or a CMOS sensor, and performs photoelectric conversion (captures) of a subject image (optical image) formed by light passing through the lens 501, and outputs an image signal (analog signal).

[0020] The A / D converter 151 converts the analog imaging signal output from the image sensor 115 into a digital imaging signal.

[0021] The digital imaging signal is written into a memory 153 via an image processing unit 152 and a memory control unit 154 (described later) or via the memory control unit 154 alone.

[0022] The image processing unit 152 performs image processing such as pixel interpolation, resizing, and color conversion on the digital imaging signal from the A / D converter 151 or memory control unit 154 to generate image data.

[0023] Furthermore, the image processing unit 152 also performs auto white balance processing based on the results of calculations using the image data.

[0024] The camera system control unit 150 is configured by a computer including a processor such as a CPU and other circuits, and controls the entire camera 100 and imaging lens 500 by executing a program recorded in a non-volatile memory 155 .

[0025] For example, the camera system control unit 150 controls the image sensor 115 and the shutter 108 in response to an image capture instruction from a user, and also performs autofocus control and aperture control based on image data generated by an image processing unit 152 .

[0026] The memory 153 temporarily records the digital imaging signal output from the A / D converter 151 and the image data generated by the image processing unit 152 .

[0027] The memory control unit 154 controls the exchange of data between the A / D converter 151 , the image processing unit 152 , and the memory 153 .

[0028] The non-volatile memory 155 is an electrically erasable and recordable read-only memory, and stores constants and programs for the operation of the camera system control unit 150 .

[0029] The system memory 156 is a readable and writable memory in which constants and variables for the operation of the camera system control unit 150, as well as programs read from the non-volatile memory 155, etc. are stored.

[0030] The system timer 157 measures the time of no operation until the camera 100 is put into an auto power off state to save power in order to prevent battery consumption when the camera 100 is not being operated by the user, and the exposure time of the image sensor 115 by the shutter 108.

[0031] The power supply unit 160 is configured from a primary battery, a secondary battery, or an AC adapter.

[0032] The power supply control unit 161 determines whether a battery is attached to the power supply unit 160, the type of the attached battery, and detects the remaining battery charge, and further supplies the required voltage to the supply destination at the required timing.

[0033] The camera communication terminal 170 is electrically connected to a lens communication terminal 506 provided in the lens unit 500 , and enables communication between the camera system control unit 150 and a lens control unit 505 in the lens unit 500 .

[0034] The recording medium I / F 171 is an interface with a recording medium 600 that is detachably attached to the camera 100 .

[0035] The recording medium 600 is a memory card, a flash memory, a hard disk, or the like, and records image data (still images and moving images) generated by the image processing unit 152.

[0036] The shake detection unit 172 is configured with a gyro sensor or the like, and outputs a signal corresponding to the shake of the camera 100 caused by hand shake or the like (hereinafter referred to as camera shake).

[0037] The above-mentioned A / D converter 151, image processing unit 152, camera system control unit 150, memory 153, and memory control unit 154 are mounted on the main board 107 as a plurality of electronic elements such as a CPU, IC, and memory chip.

[0038] The non-volatile memory 155, system memory 156, system timer 157, and power supply control unit 161 described above are mounted on the main board 107 as a plurality of electronic elements such as a CPU, ICs, and memory chips.

[0039] In addition, a recording medium I / F 171 and a shake detection unit 172 are also mounted on the main board 107.

[0040] The above-mentioned memory 153 also serves as a memory for displaying images (video memory).

[0041] The digital imaging signal and image data written to the memory 153 are displayed as a live view image or an image for image capture confirmation on a rear display unit 175 provided on the rear of the camera 100 or on an EVF display unit 176 arranged in the viewfinder via a memory control unit 154.

[0042] The rear display unit 175 and the EVF display unit 176 are configured with display elements such as a liquid crystal panel or an organic EL panel.

[0043] The operation unit 180 is an input unit that accepts operations by a user, and outputs a signal corresponding to the operation accepted here to the camera system control unit 150.

[0044] The operation unit 180 includes various operation members such as a mode changeover switch 181, a first shutter switch 183 and a second shutter switch 184 linked to a shutter button 182, a touch panel 185, a power switch 186, and the like.

[0045] A mode changeover switch 181 is operated to switch between imaging modes such as still image capture and video capture.

[0046] The shutter button 182 is operated by the user to give instructions for preparation for imaging and instructions for imaging.

[0047] The first shutter switch 183 is turned on when the shutter button 182 is pressed halfway down, and outputs a SW1 signal to the camera system control unit 150.

[0048] The second shutter switch 184 is turned ON when the shutter button 182 is fully pressed, and outputs a SW2 signal to the camera system control unit 150.

[0049] The camera system control unit 150 executes image capture preparation operations (autofocus, autoexposure, autowhite balance, etc.) in response to the SW1 signal, and executes image capture processing for a still image to be recorded in response to the SW2 signal.

[0050] The operation unit 180 also includes a touch panel 185 provided on the rear display unit 175. A power switch 186 is operated to switch the power of the camera 100 ON / OFF.

[0051] In the lens unit 500 , a lens communication terminal 506 is a camera communication terminal that enables the lens unit 500 to communicate with the digital camera 100 .

[0052] In the lens unit 500 , a lens control unit 505 that receives a control instruction from the camera system control unit 150 via communication controls the position (aperture value) of an aperture 503 and the focus of a lens 501 via an aperture driving unit 504 and a lens driving unit 502 .

[0053] (Exploded view of imaging device 100) 2 shows an exploded view of camera 100 seen obliquely from the rear side. Camera 100 has a front base 102, a rear cover 101, a top cover 103, a bottom cover 104, and a side cover 105 as exterior members.

[0054] The front base 102 is made of magnesium die-cast or resin, and has a mount 102a fixed thereto to which the lens unit 500 is attached, as well as a grip portion that allows the user to hold the camera 100.

[0055] The rear cover 101 is provided with a plurality of operating members that can be operated by the user, and a rear display unit 175 that can be opened and closed.

[0056] Also attached to the rear cover 101 are an EVF display unit 176 and a viewfinder unit 109 to which a user viewing the EVF display unit 176 brings his / her eye 700 as shown in FIG.

[0057] The top cover 103 is provided with a plurality of operating members (such as a mode changeover switch 181, a shutter button 182, and a power switch 186) that can be operated by the user.

[0058] The bottom cover 104 has an opening for exposing a battery lid that covers the opening of the battery chamber and a tripod mount that is fixed to the bottom surface of the front base 102 .

[0059] A terminal cover 105a is attached to the side cover 105 to protect an external communication terminal 107c, which will be described later.

[0060] Inside these exterior members, an imaging unit 106 having an image sensor 115 and an image blur correction mechanism, a main board 107, a shutter 108, and a chassis 110 are arranged.

[0061] The imaging section 106 has a movable section 114 that can move an imaging element 115 in two directions (yaw direction and pitch direction) that are perpendicular to an imaging optical axis (the optical axis of the lens unit 500) and perpendicular to each other.

[0062] The imaging section 106 has a fixed section (holding section) 113, which will be described later, that holds the movable section 114 so as to be movable in the above two directions.

[0063] The main board 107 is made up of a multi-layer board, and various electronic components including the above-mentioned electronic elements are mounted on both sides of the main board.

[0064] The main board 107 is fixed to the front base 102 and a metal chassis 110 with screws.

[0065] Furthermore, on the main board 107, a recording medium connector 107b for accommodating an external recording medium and an external communication terminal 107c for connecting a cable for connecting to an external device are mounted.

[0066] Among the components of the camera 100, the image sensor 115 consumes a large amount of power, generates a large amount of heat, and is prone to temperature rise.

[0067] The imaging time of the camera 100 is limited by the guaranteed operating temperature of the image sensor 115, excluding the remaining battery power.

[0068] To maximize the imaging time, it is necessary to cool the imaging element 115 so that its temperature does not exceed the guaranteed operating temperature.

[0069] The imaging unit 106 including the imaging element 115 is fixed to the front base 102 with screws, and heat from the imaging unit 106 is transferred to the front base 102 .

[0070] (Exploded view of the imaging unit 106) 3(a) and (b) show exploded views of the imaging unit 106 as viewed obliquely from the front and rear, respectively.

[0071] The imaging section 106 has a movable section 114 and a fixed section 113. The movable section 114 is composed of an imaging element 115 and a sensor holder 117 that holds the imaging element.

[0072] The imaging element 115 is configured such that a sensor chip having a plurality of pixels is fixed to an imaging substrate 115a by adhesive, and electrodes of the sensor chip and an imaging circuit on the imaging substrate 115a are electrically connected by wire bonding.

[0073] The imaging element 115 is fixed to a sensor holder 117 by adhesive.

[0074] On the rear surface (rear surface) of the imaging board 115a opposite to the surface on which the sensor chip is attached, sensor electronic elements 115b such as a capacitor, resistor, regulator, and the like that constitute an imaging circuit are mounted.

[0075] Three heat dissipation members 200, which will be described later, are disposed between the movable portion 114 and the fixed portion 113.

[0076] The sensor holder 117 is held by a fixing portion 113 so as to be movable in two directions (horizontal and vertical directions) that are perpendicular to the imaging optical axis and perpendicular to each other.

[0077] Three coils 116 are fixed to the sensor holder 117 .

[0078] The fixed portion 113 holds three magnets 118 so as to face the three coils 116. The movable portion 114 is attracted in the imaging optical axis direction (rearward) by the magnetic force of the magnets 118.

[0079] Between movable portion 114 and fixed portion 113, balls (not shown) are arranged, which are held by ball holding portions 117a provided at a plurality of positions on sensor holder 117.

[0080] As a result, the movable portion 114 is positioned relative to the fixed portion 113 in the imaging optical axis direction via the ball.

[0081] In the imaging section 106 configured in this manner, by controlling the energization of the three coils 116, it is possible to move the imaging element 115 in the two directions described above.

[0082] In response to camera shake detected through shake detection unit 172, camera system control unit 150 controls (hereinafter referred to as drive control) energization of coil 116 so as to move movable unit 114 in a direction that reduces (corrects) image blur caused by the camera shake.

[0083] The imaging unit 106 and the main board 107 are electrically connected using an FPC.

[0084] The imaging signal FPC 111 shown in FIG. 2 has wiring for transmitting the imaging signal output from the imaging element 115 and the control signals required to drive the imaging element 115, and these signals are sent to the camera system control unit 150 on the main board 107.

[0085] 2 has wiring for supplying power for driving the imaging element 115 from the power control unit 161 to the imaging element 115.

[0086] (Configuration of heat dissipation member 200) Next, a configuration for efficient heat dissipation by the above-mentioned heat dissipation member 200 will be described with reference to FIGS.

[0087] Fig. 4(a) is a cross-sectional view of the main part of the digital camera, Fig. 4(b) is a perspective view of the cross-section of the main part, and Fig. 5 is a perspective view of the heat dissipation member 200. The cross section of Fig. 4 is the AA cross section of Fig. 5.

[0088] The heat dissipation member 200 is disposed so as to be sandwiched between the fixed portion 113 and the sensor holder 117 , and is composed of a first cylindrical member 201 , a second cylindrical member 202 , and a flat plate 203 .

[0089] The first cylindrical member 201 is composed of a first cylindrical portion 201a and a thermally conductive sheet 201b.

[0090] The first cylindrical portion 201a is a metal shaft, around which a heat-conductive sheet 201b, which is a sheet member having good thermal conductivity such as a graphite sheet, is wound.

[0091] The heat conductive sheet 201b is wound around the first cylindrical portion 201a in a spiral shape, and is attached so that an end portion thereof will not create a step during rotation, as described below, and will not interfere with the rotation of the first cylindrical member 201.

[0092] A plurality of thermally conductive sheets 201b may be wound around the substrate.

[0093] The second cylindrical member 202 is composed of a second cylindrical portion 202a and a heat conductive sheet 202b.

[0094] Its configuration is the same as the first cylindrical member 201, and similarly, a plurality of sheets may be wound in layers, but the length of the cylinder may be different depending on the arrangement space.

[0095] The flat plate 203 is disposed so as to be sandwiched between the first cylindrical member 201 and the second cylindrical member 202 .

[0096] The flat plate is a metal plate such as aluminum, or a member having a graphite sheet (not shown) attached to part of its surface to enhance thermal conductivity.

[0097] Through this flat plate, first cylindrical member 201 and second cylindrical member 202 are thermally connected. The surface of flat plate 203 facing sensor holder 117 and the surface of flat plate 203 facing fixed part 113 are planes parallel to the direction in which movable part 114 moves.

[0098] Heat generated from the CMOS 115 is first transmitted to the sensor holder 117 , and then transmitted to the flat plate 203 via the thermally conductive sheet 201 b of the first cylindrical member 201 that is in contact with the sensor holder 117 .

[0099] Then, the heat is dissipated from the flat plate 203 to the fixed portion 113 through the thermally conductive sheet 202 b of the second cylindrical member 202 .

[0100] The arrows in Figure 4(b) show the heat dissipation paths. Compared to the prior art, the area available for heat dissipation has increased significantly because the contact has changed from point contact to line contact.

[0101] In order to dissipate heat more efficiently in this heat dissipation path, it is preferable that the total distance of the path is short, the diameter of the cylindrical portion is small, and it is desirable that the diameters of first cylindrical portion 201a and second cylindrical portion 202a are the same.

[0102] In practice, in consideration of the ease of attaching the thermally conductive sheet 201b to the cylindrical portions, the first cylindrical portion 201a and the second cylindrical portion 202a have the same diameter of about 0.3 to 3.0 mm in this embodiment. In addition, since the rotation angle of the image pickup element in this embodiment is 10 degrees or less, the cylindrical member will not unintentionally fall off the flat plate 203 if the size is about that of the digital camera 100.

[0103] In order to dissipate heat efficiently, it is desirable that the contact area between the first cylindrical member 201 and the flat plate 203 is equal to the contact area between the second cylindrical member 202 and the flat plate 203 .

[0104] On the other hand, since heat dissipation member 200 is arranged on the outer periphery of sensor holder 117, it is easier to arrange heat dissipation member 200 in the device if it has an elongated shape as shown in FIG.

[0105] Therefore, in this embodiment, the length of the first cylindrical members 201 is longer than the second cylindrical members 202 , and the number of the first cylindrical members 201 is smaller than that of the second cylindrical members 202 .

[0106] If the first cylindrical member 201 and the second cylindrical member 202 were made the same length and in number, the heat dissipation member 200 would have a shape close to a square, and placing the heat dissipation member 200 on the outer periphery of the sensor holder 117 would result in the digital camera 100 becoming larger, which is not preferable.

[0107] Heat dissipation member 200 is held so as to be sandwiched between fixed portion 113 and sensor holder 117, and the holding force is due to the pulling force of coil 116 described above.

[0108] The distance between fixed portion 113 and movable portion 114 is determined by the ball (not shown) held by ball holding portion 117a as described above.

[0109] In order for the heat dissipation member 200 not to affect this distance, the rigidity of the first cylindrical portion 201a and the second cylindrical portion 202a must be less than that of the ball.

[0110] Specifically, it is preferable that the ball is made of ceramic or stainless steel, and the first cylindrical portion 201a and the second cylindrical portion 202a are made of aluminum or resin parts.

[0111] The position of this ball changes within the range of ball holding portion 117a when digital camera 100 is not turned on, but is positioned at the center of ball holding portion 117a by a ball position reset operation that is performed when the power is turned on or when returning from a standby state.

[0112] During the ball position reset operation, the heat transfer member 200 is also placed at the center position of the flat plate 203 .

[0113] (Relationship between the ball 119, the first cylindrical member 201 and the flat plate 203) 9(a) to (c) show the relationship between the ball 119, the first cylindrical member 201, and the flat plate 203. In FIG.

[0114] FIG. 9(a) shows the case where the imaging element is located in the center, FIG. 9(b) shows the case where the imaging element is located at the right end, and FIG. 9(c) shows the case where the imaging element is located at the top end.

[0115] In FIG. 9(a), ball 119 is located at the center of ball holder 117a, and moves to the right (FIG. 9(b)) and up (FIG. 9(c)) as the imaging element moves.

[0116] Like the ball 119, the first cylindrical member 201 and the flat plate 203 are located in the center of the ball holding portion 117a in FIG. 9(a) and move to the right (FIG. 9(b)) and up (FIG. 9(c)) as the imaging element moves.

[0117] As for the second cylindrical member 202 (not shown), like the first cylindrical member 201 described above, when the sensor holder 117 moves, it rolls in a direction in which the first cylindrical member 201 does not move, and remains in place when the first cylindrical member 201 moves.

[0118] During the operation of the image blur correction device, the driving range of the sensor holder 117 is controlled so that the first cylindrical member 201 and the second cylindrical member 202 (not shown) do not fall off the flat plate 203 .

[0119] When the device is turned off, it is preferable to have a fall-prevention shape as shown in the modified example.

[0120] In camera 100, sensor holder 117 moves in two directions, the left-right direction and the depth direction in FIG.

[0121] At that time, when the sensor is driven in the left-right direction, the first cylindrical member 201 moves while rotating in the left-right direction while being sandwiched between the sensor holder 117 and the flat plate 203 .

[0122] When driven in the depth direction, the second cylindrical member 202 moves while rotating in the depth direction while being sandwiched between the fixed portion 113 and the flat plate 203 .

[0123] The amount of movement due to the rolling of the first cylindrical member 201 and the second cylindrical member 202 is half the amount of drive of the sensor holder 117 in each direction.

[0124] The flat plate 203 is provided with a fall prevention convex shape 203a and a fall prevention wall shape 203b as shown in FIG.

[0125] The fall prevention convex shapes 203a are arranged on both ends of the flat plate 203 in the direction of rotational movement of the cylindrical member.

[0126] The distance between the fall prevention convex shape 203a and the fall prevention wall shape 203b in the axial direction of the cylindrical member is at least shorter than the axial length of the cylindrical member, and more preferably shorter than the diameter thereof.

[0127] In FIG. 5, two fall prevention convex shapes 203a are provided on one side, but one or three or more may be provided as long as the above conditions are met.

[0128] The fall prevention wall shapes 203b are disposed over the entire area of ​​both ends of the cylindrical member on the flat plate 203 in the direction of the rotation axis.

[0129] The fall prevention convex shape 203a functions as a stopper that prevents the first cylindrical member 201 and the second cylindrical member 202 from falling off the flat plate 203 when they are rotated.

[0130] In addition, the fall prevention wall shape 203b functions as a stopper that prevents the first cylindrical member 201 and the second cylindrical member 202 from falling off the flat plate 203 if they are shifted in the direction of the rotation axis during rotational movement due to the driving force of the movable part 114 or external disturbance.

[0131] The distance between the opposing fall prevention convex shapes 203a must be such that the first cylindrical member 201 and the second cylindrical member 202 do not come into contact with the stoppers during the driving of the movable part 114, thereby preventing the driving from being hindered.

[0132] For this reason, it must be wider than at least "(diameter of the cylindrical portion) x (number of cylinders) + (driving stroke of the movable portion 114) / 2".

[0133] In addition, in order to suppress vibration of the rotation axis of the cylindrical member on the flat plate 203, it is preferable that the distance between the opposing fall prevention wall shapes 203b is longer than the "axial length of the cylindrical member" and shorter than "(axial length of the cylindrical member) + (diameter of the cylindrical portion)".

[0134] The fall prevention convex shape 203a and the fall prevention wall shape 203b can exhibit the greatest fall prevention effect when their height from the flat plate 203 is greater than the radius of the cylindrical member.

[0135] In this embodiment, the fall prevention convex shape 203a and the fall prevention wall shape 203b are provided on the flat plate 203, but they may be provided on at least two of the following four faces. 1. The surface of the sensor holder 117 facing the first cylindrical member 201. 2. The surface of the flat plate 203 facing the first cylindrical member 201. 3. The surface of the fixed portion 113 facing the second cylindrical member 202. 4. The surface of the flat plate 203 facing the second cylindrical member 202.

[0136] (Variation in rolling resistance) The movable portion 114 is driven linearly and rotary, and from the viewpoint of drive control, it is preferable that the heat dissipation member 200 has as small a variation in rolling resistance as possible in either case.

[0137] An arrangement that reduces the variation will be described with reference to Fig. 6. Fig. 6 is a front view of fixing portion 113 and heat dissipation member 200.

[0138] In FIG. 6, the heat dissipation member 200 is disposed at a position that does not intersect with the XY axes that pass through the center of the imaging section of the CMOS 115, and the length of its long side is shorter than half the length of each side of the CMOS 115.

[0139] By adopting this arrangement and dimensions, even when the movable part 114 is rotationally driven, the distance from the center of rotation to the heat dissipation member 200 is large.

[0140] Therefore, the relative movement directions of the movable part and the fixed part are substantially the same at both ends of the heat dissipation member 200. Therefore, the rotation directions of the heat dissipation member 200 are the same at both ends, so that the heat dissipation member 200 can roll stably without being twisted.

[0141] The features of this embodiment are listed below.

[0142] A first feature of the present invention is that it has an imaging element, a movable part 114 on which the imaging element is mounted and which is movable in a first direction X perpendicular to the optical axis and in a second direction Y perpendicular to the first direction and the optical axis, and a holding part 113 which holds the movable part.

[0143] The heat dissipation member 200 is sandwiched in the optical axis direction Z between the movable portion and the holding portion (fixed portion).

[0144] The heat dissipation member has at least a plurality of first cylindrical members 201 arranged so that their central axes are perpendicular to the first direction, and a plurality of second cylindrical members 202 arranged so that their central axes are perpendicular to the second direction.

[0145] The first surface along which a plurality of first cylindrical members rotate in a first direction and the second surface along which a plurality of second cylindrical members rotate in the second direction are stacked and arranged in the optical axis direction.

[0146] A second feature is that it has a retraction portion 116 that generates a force that draws the movable portion 114 and the holding portion 113 closer to each other in the optical axis direction.

[0147] As a third feature, the first surface and the second surface are arranged in parallel and are perpendicular to the optical axis. One surface of the plane 203 is the first surface (XY plane), and the other surface of the plane 203 is the second surface (XY plane).

[0148] The fourth feature is that a flat plate 203 is disposed between the first surface and the second surface (FIG. 4).

[0149] A fifth feature is that the movement distance of the first cylindrical member 201 which rotates is the same as the movement distance of the second cylindrical member 202 which rotates.

[0150] A sixth feature is that the diameter of each of the multiple first cylindrical members 201 is the same length, the diameter of each of the multiple second cylindrical members 202 is the same length, and the diameter of the first cylindrical member 201 and the diameter of the second cylindrical member 202 are the same length.

[0151] As a seventh feature, a length of the first cylindrical member in a cylindrical axial direction is shorter than half a length of the imaging element in a direction perpendicular to the first direction X, and a length of the second cylindrical member in a cylindrical axial direction is shorter than half a length of the imaging element in a direction perpendicular to the second direction Y; the first cylindrical member 201 is disposed in a region that does not intersect with an axis of a first direction passing through the rotation center of the imaging element, The second cylindrical member 202 is characterized in that it is disposed in a region that does not always intersect with an axis in the second direction that passes through the center of rotation of the imaging element.

[0152] As an eighth feature, the surface of the first cylindrical member 201 and the surface of the second cylindrical member 202 are formed of a heat conductive material.

[0153] A ninth feature is that the first cylindrical member and the second cylindrical member are elastic members, and the tolerance of each of the first cylindrical member 201 and the second cylindrical member 202 is smaller than the amount of deformation of the first cylindrical member or the second cylindrical member caused by the retraction portion 116.

[0154] A tenth feature is that the flat plate 203 is made of metal, or the surface of the flat plate 203 is covered with a heat conductive sheet.

[0155] (Variation 1) As a first modification of this embodiment, a configuration for further improving the reliability of the rolling drive of the heat dissipation member 200 will be described with reference to Figs. 7 and 8. Fig. 7(a) is a cross-sectional view of a main part of this first modification, Fig. 7(b) is a perspective view of the cross-sectional view of the main part, and Fig. 8 is a perspective view of the main part of this first modification. The cross section in Fig. 7 is the cross section BB in Fig. 8.

[0156] When the power supply to the camera 100 is turned off, the current supply to the coil 116 is stopped, and the pulling force of the coil 116 is weakened.

[0157] In order to improve the repeatability of the positions of the first cylindrical member 201 and the second cylindrical member 202 and to facilitate control, it is preferable that the position of the heat dissipation member 200 can be determined to some extent even when the power is turned off.

[0158] For this purpose, the sensor holder 117 further has a movable plate fall-off prevention shape 117a.

[0159] As a result, even if the heat dissipation member 200 moves significantly in the left-right direction in FIG. 7, the movable-side flat plate fall-out prevention shape 117a and the flat plate 203 come into contact, preventing the first cylindrical member 201 from jumping out of the projection surface of the sensor holder 117.

[0160] The fixed portion 113 has a shape 113a for preventing the fixed plate from falling off.

[0161] As a result, even if the heat dissipation member 200 moves significantly in the depth direction in FIG. 7, the fixed side flat plate fall-out prevention shape 113a and the flat plate 203 come into contact, preventing the second cylindrical member 202 from jumping out of the projection plane of the fixed portion 113.

[0162] If the position when the power is turned off can be specified to some extent by this configuration, the reproducibility of the initial position of the CMOS 115 can be improved by the above-mentioned initial drive operation.

[0163] Of the four surfaces, namely the opposing surface of fixed portion 113, the opposing surface of movable portion 114, and the front and back surfaces of flat plate 203, at least two surfaces have protrusions 117a provided outside the movable area of ​​first cylindrical member 201 or second cylindrical member 202.

[0164] The features of this embodiment are listed below.

[0165] The eleventh feature is as follows: Of the four surfaces, namely, the surface of holding part 113 facing movable part 114, the surface of the movable part facing the holding part, and the front and back surfaces of flat plate 203, at least two surfaces are provided with protrusions 117a outside the movable area of ​​first cylindrical member 201 or second cylindrical member 202.

[0166] Furthermore, the first cylindrical member 201 and the second cylindrical member 202 each have a plurality of cylinders, and when the cylinders come into contact with each other, frictional resistance is generated, resulting in deterioration of controllability.

[0167] To prevent this, the first modified example has a contact prevention convex shape 203c as shown in FIG.

[0168] The contact prevention convex shapes 203c are provided between all of the cylinders of the first cylindrical member 201, and are also provided between all of the cylinders of the second cylindrical member 202.

[0169] This makes it possible to prevent the controllability from deteriorating. The interval between the contact prevention convex shapes 203c needs to be at least wider than "(diameter of the cylindrical portion)+(driving stroke of the movable portion 114) / 2".

[0170] Alternatively, it is possible to define the distance between all the cylinders by attaching a shaft to each of the cylindrical portions 201a of the first cylindrical member 201 and fixing the shafts together (for example, like the wheels of a train).

[0171] In the case of a device in which the driving force generated by coil 116 is large, this configuration may be adopted since the occurrence of frictional resistance in the shaft portion and the increase in the weight of the moving portion can be ignored.

[0172] The thickness of the heat dissipation member 200 may vary to some extent due to tolerances.

[0173] In the present invention, in order for the first cylindrical member 201 and the second cylindrical member 202 to dissipate heat, a configuration in which there is constant contact between the fixed portion 113, the flat plate 203, and the sensor holder 117 is able to dissipate more heat.

[0174] In order to maintain constant contact even when component tolerances and drive flatness are taken into consideration, it is preferable to use a heat dissipation sheet 204 that is an elastic member.

[0175] It is preferable that the heat dissipation sheet 204 has low rigidity so that the amount of deformation of the heat dissipation sheet 204 caused by the pulling force of the coil 116 described above is greater than the amount of variation caused by tolerances.

[0176] The above-described embodiments and modifications are merely representative examples, and various modifications and changes are possible for each embodiment and modification when implementing the present invention.

[0177] While this embodiment describes a blur correction device, the present invention can also be applied to any device that drives an image sensor, such as a device equipped with a function for moving the image sensor to perform pixel-enhancing processing (pixel shift).

[0178] The characteristic features of the present invention are listed below.

[0179] (Configuration 1) an imaging device having an imaging element, a movable portion on which the imaging element is mounted and which is movable in a first direction perpendicular to an optical axis and a second direction perpendicular to the first direction and the optical axis, a holding portion which holds the movable portion, and a heat dissipation member sandwiched between the movable portion and the holding portion in the optical axis direction, the heat dissipation member has at least a plurality of first cylindrical members arranged such that their central axes are perpendicular to the first direction, and a plurality of second cylindrical members arranged such that their central axes are perpendicular to the second direction, An imaging device characterized in that a first surface along which the plurality of first cylindrical members rotate in the first direction and a second surface along which the plurality of second cylindrical members rotate in the second direction are stacked and arranged in an optical axis direction.

[0180] (Configuration 2) 2. The imaging device according to configuration 1, further comprising a retraction portion that generates a force that moves the movable portion and the holding portion closer to each other in the optical axis direction.

[0181] (Configuration 3) 3. The imaging device according to configuration 1 or 2, wherein the first surface and the second surface are arranged in parallel and perpendicular to an optical axis.

[0182] (Configuration 4) 4. The imaging device according to any one of configurations 1 to 3, wherein a flat plate is disposed between the first surface and the second surface.

[0183] (Configuration 5) 5. The imaging device according to any one of configurations 1 to 4, wherein a moving distance of the first cylindrical member which rotates is the same as a moving distance of the second cylindrical member which rotates.

[0184] (Configuration 6) The imaging device described in any one of configurations 1 to 5, characterized in that the diameter of each of the multiple first cylindrical members is the same length, the diameter of each of the multiple second cylindrical members is the same length, and the diameter of the first cylindrical member and the diameter of the second cylindrical member are the same length.

[0185] (Configuration 7) a length in a cylindrical axial direction of the first cylindrical member is shorter than half a length of the imaging element in a direction perpendicular to a first direction, and a length in a cylindrical axial direction of the second cylindrical member is shorter than half a length of the imaging element in a direction perpendicular to a second direction; the first cylindrical member is disposed in a region that does not intersect with an axis of a first direction passing through a rotation center of the imaging element, The imaging device according to any one of configurations 1 to 6, characterized in that the second cylindrical member is arranged in an area that does not always intersect with an axis of a second direction passing through the center of rotation of the imaging element.

[0186] (Configuration 8) 8. The imaging device according to any one of configurations 1 to 7, wherein a surface of the first cylindrical member and a surface of the second cylindrical member are formed of a thermally conductive material.

[0187] (Configuration 9) The imaging device described in any one of configurations 1 to 8, characterized in that the first cylindrical member and the second cylindrical member are elastic members, and the tolerance of each of the first cylindrical member and the second cylindrical member is smaller than the amount of deformation of the first cylindrical member or the second cylindrical member caused by the retraction portion.

[0188] (Configuration 10) 9. The imaging device according to any one of configurations 1 to 8, wherein the flat plate is made of metal, or a surface of the flat plate is covered with a heat conductive sheet.

[0189] (Configuration 11) The imaging device described in any one of configurations 1 to 10, characterized in that at least two of the four surfaces, namely, the opposing surface of the holding part facing the movable part, the opposing surface of the movable part facing the holding part, and the front and back surfaces of the flat plate, have protrusions provided outside the movable area of ​​the first cylindrical member or the second cylindrical member. [Explanation of symbols]

[0190] 100 Digital Camera 113 Fixed part 114 Moving parts 200 Heat dissipation material 201 First cylindrical member 202 Second cylindrical member 203 Flat plate

Claims

1. an imaging device having an imaging element, a movable portion on which the imaging element is mounted and which is movable in a first direction perpendicular to an optical axis and a second direction perpendicular to the first direction and the optical axis, a holding portion which holds the movable portion, and a heat dissipation member sandwiched between the movable portion and the holding portion in the optical axis direction, the heat dissipation member has at least a plurality of first cylindrical members arranged such that their central axes are perpendicular to the first direction, and a plurality of second cylindrical members arranged such that their central axes are perpendicular to the second direction, An imaging device characterized in that a first surface along which the plurality of first cylindrical members rotate in the first direction and a second surface along which the plurality of second cylindrical members rotate in the second direction are stacked and arranged in an optical axis direction.

2. 2. The imaging device according to claim 1, further comprising a retraction portion that generates a force that moves the movable portion and the holding portion closer to each other in the optical axis direction.

3. 2. The imaging device according to claim 1, wherein the first surface and the second surface are arranged in parallel and are perpendicular to an optical axis.

4. 2. The imaging device according to claim 1, further comprising a flat plate disposed between the first surface and the second surface.

5. 2. The imaging device according to claim 1, wherein a moving distance of the first cylindrical member which rotates is the same as a moving distance of the second cylindrical member which rotates.

6. 2. The imaging device according to claim 1, wherein the diameter of each of the plurality of first cylindrical members is the same length, the diameter of each of the plurality of second cylindrical members is the same length, and the diameter of the first cylindrical member and the diameter of the second cylindrical member are the same length.

7. a length in a cylindrical axial direction of the first cylindrical member is shorter than half a length of the imaging element in a direction perpendicular to a first direction, and a length in a cylindrical axial direction of the second cylindrical member is shorter than half a length of the imaging element in a direction perpendicular to a second direction; the first cylindrical member is disposed in a region that does not intersect with an axis of a first direction passing through a rotation center of the imaging element, 2. The imaging device according to claim 1, wherein the second cylindrical member is disposed in a region that does not intersect with an axis of the second direction that passes through a rotation center of the imaging element.

8. 2. The imaging device according to claim 1, wherein a surface of the first cylindrical member and a surface of the second cylindrical member are formed of a thermally conductive material.

9. 3. The imaging device according to claim 2, characterized in that the first cylindrical member and the second cylindrical member are elastic members, and the tolerances of the first cylindrical member and the second cylindrical member are smaller than the amount of deformation of the first cylindrical member or the second cylindrical member caused by the retraction portion.

10. 5. The imaging device according to claim 4, wherein the flat plate is made of metal, or the surface of the flat plate is covered with a heat conductive sheet.

11. The imaging device described in claim 4, characterized in that at least two of the four surfaces, including the opposing surface of the holding part facing the movable part, the opposing surface of the movable part facing the holding part, and the front and back surfaces of the flat plate, have protrusions provided outside the movable area of ​​the first cylindrical member or the second cylindrical member.

Images