Optical element driving device and optical instrument

Abstract

To provide a small-sized optical element driving device that reduces variations of the position of an optical element in an optical axis direction due to the shift of the optical element.SOLUTION: An optical element driving device 20 has: a stationary member 21 that is fixed to a body of an optical instrument 10a; a movable unit 20b that holds an optical element 11 and is movable in a first direction relative to the stationary member; and an actuator that drives the movable unit in the first direction relative to the stationary member. The movable unit has: a first movable member 31 that holds the optical element; a second movable member 32 that is connected to the first movable member and receives a driving force generated by the actuator; and adjustment mechanisms 41a-41c that adjust the position of the first movable member relative to the second movable member in a second direction orthogonal to the first direction.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an optical element driving device that moves an optical element for vibration isolation or the like. [Background technology]

[0002] In order to reduce image blur caused by vibrations such as camera shake and to assist in tracking a moving object during panning imaging, optical device drivers are installed in optical devices to move (shift) optical elements such as image sensors and lenses relative to the optical axis of the imaging optical system. In the optical device driver, an actuator such as a voice coil motor (VCM) drives a movable unit including an optical element relative to a fixed member fixed to the main body of the optical device.

[0003] In such an optical element driving device, it is desirable to be able to adjust the position of the optical element in the optical axis direction. Patent Document 1 discloses an optical element driving device equipped with an adjustment mechanism that adjusts the position of the imaging surface of the imaging element (flange back from the flange surface) by integrally moving a fixed member and a movable unit that holds the imaging element. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-144165 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in a configuration in which the fixed member and the movable unit are moved integrally, the optical element driving device including the adjustment mechanism becomes large.

[0006] Furthermore, if the imaging element is held by the movable unit so that the imaging surface is tilted relative to the plane perpendicular to the optical axis due to manufacturing errors, it is necessary to adjust the tilt of the fixed member and the movable unit using the adjustment mechanism so that the imaging surface is parallel to the plane perpendicular to the optical axis. However, if the movable unit is driven in a state in which the fixed member is tilted relative to the plane perpendicular to the optical axis due to tilt adjustment, fluctuations in the flange focal distance will increase.

[0007] The present invention provides a small optical element driving device that minimizes fluctuations in the position of an optical element in the optical axis direction due to shifting of the optical element, and an optical apparatus equipped with the same. [Means for solving the problem]

[0008] An optical element driving device according to one aspect of the present invention comprises a fixed member fixed to a body of an optical device, a movable unit that holds an optical element and is movable in a first direction relative to the fixed member, and an actuator that drives the movable unit in the first direction relative to the fixed member. The movable unit comprises a first movable member that holds the optical element, a second movable member that is connected to the first movable member and receives a driving force from the actuator, and an adjustment mechanism that adjusts the position of the first movable member in a second direction perpendicular to the first direction relative to the second movable member. Note that an optical device equipped with the optical element driving device also constitutes another aspect of the present invention. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a small optical element driving device in which movement of the optical element in the first direction causes little fluctuation in the position of the optical element in the second direction. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a block diagram showing the configuration of an imaging device including a sensor driving device according to a first embodiment. [Figure 2] FIG. 2 is a perspective view showing the front appearance of the imaging device according to the first embodiment. [Figure 3] FIG. 2 is a perspective view showing the rear appearance of the imaging device according to the first embodiment. [Figure 4] 1 is an exploded perspective view showing the internal configuration of an imaging device according to a first embodiment when viewed from the rear side. [Figure 5] FIG. 2 is an exploded perspective view of the sensor driving device of the first embodiment as viewed from the front side. [Figure 6] FIG. 2 is an exploded perspective view of the movable unit of the sensor driving device according to the first embodiment, as viewed from the front side. [Figure 7] FIG. 2 is an exploded perspective view of the movable unit of the sensor driving device according to the first embodiment as viewed from the rear side. [Figure 8] FIG. 3 is a cross-sectional view of a connecting portion between first and second movable members in the sensor driving device of the first embodiment. [Figure 9] 5A and 5B are schematic diagrams showing changes in flange focal length in the sensor driving device of the first embodiment. [Figure 10] FIG. 10 is an exploded perspective view showing the internal configuration of an imaging device according to a second embodiment. [Figure 11] 10A and 10B are a rear view and a cross-sectional view showing the internal configuration of an imaging device according to a second embodiment. [Figure 12] 10A and 10B are schematic diagrams showing changes in flange focal length in a conventional sensor driving device. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. [Example]

[0012] FIG. 1 shows the configuration of a camera system 10 including an imaging device (hereinafter referred to as a camera) 10a as an optical device equipped with an optical element driving device (hereinafter referred to as a sensor vibration isolation device) 20 according to a first embodiment of the present invention, and an interchangeable lens 10b detachably attached to the imaging device. The camera 10a is a mirrorless digital camera without a quick-return mirror, and includes an imaging element 11, a base member 13c, a mount member 13a, a camera control unit 14, a first vibration isolation control unit 15a, a first vibration detection unit 16a, an image processing unit 17, and a sensor vibration isolation device 20. Another optical device, an interchangeable lens 10b, includes an imaging optical system 12, a mount member 13b, a second vibration isolation control unit 15b, a second vibration detection unit 16b, and a lens vibration isolation device 60 as an optical element driving device. The imaging optical system 12 is composed of multiple lens groups (not shown), including a correction lens 12b.

[0013] In the following description, the central axis of the imaging optical system 12 is referred to as the optical axis 12a, the Z direction in which the optical axis 12a extends is referred to as the optical axis direction (second direction), the X direction (horizontal direction) and the Y direction (vertical direction), which are perpendicular to the optical axis 12a and perpendicular to each other, are collectively referred to as the shift direction (first direction), and the XY plane perpendicular to the optical axis 12a is referred to as the shift plane 12c.

[0014] When the sensor vibration isolation device 20 is in a non-operating state, the optical axis 12a passes through the center of the imaging surface 11a of the imaging element 11 and is perpendicular to the imaging surface 11a. The imaging element 11 as an optical element is composed of a photoelectric conversion element such as a CMOS sensor or a CCD sensor, and has a plurality of pixels on the imaging surface 11a. The imaging element 11 photoelectrically converts (captures) an object image (optical image) formed on the imaging surface 11a by the imaging optical system 12 and outputs an imaging signal. Image data is generated by performing various processes on the imaging signal in the image processing unit 17. The image data is stored in a memory (storage medium) not shown.

[0015] The base member 13c constitutes the chassis of the camera 10a. The mount member 13a and the sensor vibration isolation device 20 (fixed members described below) are fixed to the base member 13c, and the mount member 13a is coupled to the mount member 13b of the interchangeable lens 10b. At this time, communication between the camera 10a and the interchangeable lens 10b is possible. The sensor vibration isolation device 20 (movable unit described below) holds the image sensor 11 so that it can move in the shift direction.

[0016] The sensor vibration isolation device 20 reduces (corrects) image blur caused by vibrations of the camera 10a due to camera shake or the like by moving the imaging element 11 in a shift direction (translation: hereinafter referred to as shift) or rotating it in a plane parallel to the imaging surface 11a. The first vibration detection unit 16a is composed of a gyro sensor, an acceleration sensor, etc., and detects vibrations of the camera 10a and outputs a vibration detection signal. The first vibration isolation control unit 15a controls an actuator (described later) in the sensor vibration isolation device 20 based on the vibration detection signal from the first vibration detection unit 16a to translate or rotate the imaging element 11. Note that a configuration may be adopted in which the imaging element 11 is moved in the optical axis direction when the imaging element 11 is translated.

[0017] The camera control unit 14 is configured by a computer including a CPU and the like, and controls the overall operation of the camera system 10 upon receiving user input via an operation unit (not shown).

[0018] The lens vibration isolation device 60 corrects image blur caused by vibrations of the interchangeable lens 10b due to camera shake or the like by shifting (translating) the correction lens 12b, which serves as an optical element, in a shift direction and rotating it around its optical axis. The second vibration detection unit 16b is composed of a gyro sensor, an acceleration sensor, or the like, and detects vibrations of the interchangeable lens 10b and outputs a vibration detection signal. The second vibration isolation control unit 15a controls the actuator in the lens vibration isolation device 60 based on the shake detection signal from the second vibration detection unit 16b to translate or rotate the correction lens 12b. Note that a configuration may be adopted in which the correction lens 12b moves in the optical axis direction when the correction lens 12b translates. The interchangeable lens 10b does not necessarily have to include the lens vibration isolation device 60, the second vibration detection unit 16b, and the second vibration isolation control unit 15a.

[0019] 2 and 3 show the exterior of camera 10a without interchangeable lens 10b, viewed from the front (subject side) and rear, respectively. Camera 10a has a display 102, touch panel 103, viewfinder display 104, shutter button 105, mode selector switch 106, terminal cover 107, main electronic dial 108, rear operation unit 109, power switch 110, and sub electronic dial 111. Camera 10a also has a selection member 126, video button 114, AE lock button 115, magnification button 116, playback button 117, menu button 119, eyepiece 121, eyepiece detection unit 123, cover 124, grip 125, and lock button 127.

[0020] The display unit 102 is a display device such as an LCD provided on the back of the camera 10a, and displays images and various information. The touch panel 103 is arranged on the display surface of the display unit 102, and detects touch operations on the display surface (operation surface). The out-of-viewfinder display unit 104 is provided on the top surface of the camera 10a, and displays various setting values such as shutter speed and aperture. The shutter button 105 is an operation member that the user operates to instruct imaging. The mode change switch 106 is an operation member that the user operates to switch imaging modes.

[0021] The terminal cover 107 is a member that protects a connector (not shown) to which a cable or the like that connects an external device (not shown) to the camera 10a is attached or detached. The main electronic dial 108 is an operating member that is rotated by the user to change settings such as shutter speed and aperture. The power switch 110 is an operating member that is operated by the user to turn the power of the camera 10a on and off.

[0022] The sub electronic dial 111 is an operating member operated by the user to move a selection frame for selecting an area for AF or photometry, advance images displayed on the display unit 102, and the like. A rear operation unit 109 is provided on the rear surface of the camera 10a. The rear operation unit 109 includes multiple push buttons, a SET button 113, and a rear dial 112. The rear dial 112 is an operating member operated by the user to change settings such as shutter speed and aperture. The SET button 113 is a push button operated mainly by the user to confirm a selection item, etc. The selection member 126 is a cross (four-way) key that can be operated by pressing the corresponding parts on the up, down, left, and right, respectively, and can cause the camera 10a to execute a function corresponding to the part that is pressed.

[0023] The video button 114 is an operating member operated by the user to issue an instruction to start / stop video capture. The AE lock button 115 is an operating member operated by the user to fix the exposure state in a capture standby state. The enlargement button 116 is an operating member operated by the user to turn on / off the enlargement mode when a live view (LV) image is displayed on the display unit 102 in the capture mode. By turning on the enlargement mode and then operating the main electronic dial 108, the LV image can be enlarged or reduced. In addition, the enlargement button 116 is operated in the playback mode to increase the magnification ratio of the playback image displayed on the display unit 102.

[0024] The playback button 117 is an operating member operated by the user to switch between image capture mode and playback mode. When the playback button 117 is pressed in image capture mode, the camera control unit 14 transitions the operation mode to playback mode and displays on the display unit 102 a playback image corresponding to the latest image data among the image data stored in a memory (not shown). The menu button 119 is an operating member operated by the user to display on the display unit 102 a menu screen for making various settings. The user can intuitively make various settings using the menu screen displayed on the display unit 102, the rear dial 112, and the SET button 113.

[0025] A user can view an LV image or a playback image displayed on an EVF 122 provided in the camera 10a through an eyepiece 121 provided in an eyepiece finder (look-in finder). An eyepiece detection unit 123 is a sensor that detects whether or not the user has brought their eye close to the eyepiece 121. A lid 124 is an openable and closable member that protects a slot for installing a memory (not shown).

[0026] The grip section 125 is a part that the user holds with the right hand when holding the camera system 10. When the camera 10a is held by gripping the grip section 125 with the little finger, ring finger, and middle finger of the right hand, the shutter button 105 and the main electronic dial 108 are located at positions that can be operated with the index finger of the right hand. In the same state, the sub electronic dial 111 and the selection member 126 are located at positions that can be operated with the thumb of the right hand.

[0027] The image sensor 11 is configured as the aforementioned photoelectric conversion element, for example, a 35 mm full-size CMOS sensor with an effective area of 24 mm × 36 mm. The mount member 13a is a structural member for attaching and detaching the interchangeable lens 10b to the camera 10a. A communication terminal 120 for communicating between the camera 10a and the interchangeable lens 10b is provided inside the mount member 13a. The camera 10a can be fitted with not only a lens that can expose the entire effective area of the full-size image sensor 11 (a full-size compatible lens) but also a lens with a format that has a smaller exposure area (for example, an APS-C compatible lens) as the interchangeable lens 10b.

[0028] When interchangeable lens 10b is attached to camera 10a, a locking mechanism (not shown) holds (locks) interchangeable lens 10b. When the user presses lock button 127, the lock is released, allowing interchangeable lens 10b to be removed from camera 10a. Strap threading sections 190 and 195 are provided in two locations on camera 10a, through which a string-like member (not shown) for carrying, such as a strap, can be passed.

[0029] 4 shows an exploded view of the internal configuration of camera 10a as seen from the rear side. Inside camera 10a, the above-mentioned base member 13c, shutter member 140, main frame 150, and main board 160 are arranged. Shutter member 140 opens and closes the shutter opening by moving shutter curtain 142, thereby controlling the amount of exposure of image sensor 11. The shutter member 140 is fixed to base member 13c by screws 145a, 145b, and 145c inserted into holes 141a, 141b, and 141c provided in three locations on the shutter member 140, which are then tightened into three first screw holes 131a, 131b, and 131c in the base member 13c.

[0030] Holes 430a, 430b, and 430c are formed in fixing member 21 of sensor vibration isolation device 20 at positions corresponding to the three second screw holes 132a, 132b, and 132c of base member 13c. Fixing member 21 is fixed to base member 13c by fastening fixing screws 431a, 431b, and 431c inserted into holes 430a, 430b, and 430c into second screw holes 132a, 132b, and 132c.

[0031] Main frame 150 is a sheet metal member made of a metal with high thermal conductivity (stainless steel, aluminum, carbon steel, copper, etc.). Holes 152a, 152b, 152c, and 152d are formed in four places on main frame 150. Main frame 150 has the function of diffusing and dissipating heat generated inside camera 10b.

[0032] An electronic circuit is formed on the main board 160. Various electronic components such as a CPU 164 and a card connector 169 are mounted on the surface of the main board 160. A plurality of connectors 165, 166a, 166b, 167a, 167b, 167c, and 168 are also mounted on the main board 160. A flexible printed circuit board (FPC) 37 that is connected to the imaging element 11 and transmits imaging signals, and a driving FPC 35 that drives the actuator are electrically connected to the connectors 167a, 167b, 167c, and 168.

[0033] Furthermore, holes 162a, 162b, 162c, and 162d are formed in four locations on the main board 160. Screws 163a, 163b, 163c, and 163d are inserted into the holes 162a to 162d and the holes 152a to 152d of the main frame 150. The main board 160 is fixed to the base member 13c together with the main frame 150 by fastening the screws 163a to 163d into the four third screw holes 133a, 133b, 133c, and 133d of the base member 13c. In this way, the main frame 150, together with the base member 13c, constitute the main body of the camera 10a.

[0034] An FPC 146 for shutter drive and lead wires 147a and 147b are attached to the shutter member 140, and these are respectively connected to connectors 165, 166a and 166b on the main board 160. This allows signals and power to be transmitted between the main board 160 and the shutter member 140.

[0035] The configuration of the sensor vibration isolation device 20 will now be described in detail. The configuration of the lens vibration isolation device 60 is similar to that of the sensor vibration isolation device 20. Figure 5 shows an exploded view of the sensor vibration isolation device 20 seen from the front side. The sensor vibration isolation device 20 has a fixed unit 20a and a movable unit 20b that can shift and rotate within the shift plane 12c relative to the fixed unit 20a.

[0036] The fixed unit 20a includes a fixed member 21, a rear yoke 22, a first magnet 26a, a second magnet 26b, and a third magnet 26c. The first magnet 26a, the second magnet 26b, and the third magnet 26c are each fixed to the fixed member 21 by adhesive or the like. The first magnet 26a, the second magnet 26b, and the third magnet 26c are each composed of two magnets arranged so as to be magnetized in the optical axis direction and generate magnetic fields in opposite directions. However, they may also be composed of a single magnet that is magnetized into two poles.

[0037] The rear yoke 22 is fixed to the fixed member 21 with screws 42a, 42b, and 42c via a first cylindrical member 23a, a second cylindrical member 23b, and a third cylindrical member 23c serving as spacers (pillar members). The rear yoke 22 is disposed on the opposite side of the second movable member 32 from the fixed member 21 in the optical axis direction.

[0038] The first magnet 26a fixed to the fixed member 21 and the rear yoke 22 form a first magnetic circuit, the second magnet 26b and the rear yoke 22 form a second magnetic circuit, and the third magnet 26c and the rear yoke 22 form a third magnetic circuit.

[0039] 6 and 7 show the movable unit 20b exploded as viewed from the front and rear sides, respectively. The movable unit 20b has an imaging element 11, a first movable member 31, and a second movable member 32. The imaging element 11 is held by the first movable member 31 by being fixed to the first movable member 31 with adhesive or the like. The movable unit 20b also has a first coil 33a, a second coil 33b, a third coil 33c, and the aforementioned driving FPC 35. The driving FPC 35 is arranged so as to overlap the first coil 33a, the second coil 33b, and the third coil 33c when viewed in the optical axis direction, and is fixed to the second movable member 32 with adhesive or the like. The first movable member 31 and the second movable member 32 are arranged on opposite sides of the fixed member 21 in the optical axis direction.

[0040] Female threads 31a, 31b, and 31c protruding from the rear surface are formed at three locations on the first movable member 31 that holds the imaging element 11. The first movable member 31 is connected to the second movable member 32 by threading adjustment screws 41a, 41b, and 41c inserted (held) in holes formed at three locations on the second movable member 32 into the female threads 31a, 31b, and 31c. Elastic members 40a, 40b, and 40c, such as coil springs, are disposed on the outer peripheries of the female threads 31a, 31b, and 31c at the three connection locations (adjustment locations) where the first movable member 31 and the second movable member 32 are connected. The elastic members 40a, 40b, and 40c generate a biasing force that acts in a direction that separates the first movable member 31 from the second movable member 32 in the optical axis direction.

[0041] By rotating the adjustment screws 41a, 41b, and 41c relative to the female thread portions 31a, 31b, and 31c, it is possible to adjust the position of the first movable member 31 that holds the imaging element 11 relative to the second movable member 32 in the optical axis direction. In other words, it is possible to adjust the flange focal length, which is the distance from the mount surface of the mount member 13a to the imaging surface 11a of the imaging element 11. In this way, the female thread portions 31a, 31b, and 31c and the adjustment screws 41a, 41b, and 41c form an adjustment mechanism.

[0042] Furthermore, by rotating any of the adjustment screws 41a, 41b, and 41c, it is possible to adjust the tilt of the first movable member 31 relative to the second movable member 32. As a result, if the imaging element 11 is held by the first movable member 31 so that the imaging surface 11a is tilted relative to the shift surface 12c due to a manufacturing error, it is possible to adjust the tilt of the first movable member 31 relative to the second movable member 32 so that the imaging surface 11a becomes parallel to the shift surface 12c.

[0043] Note that a configuration may be adopted in which spacer members such as washers are disposed at the connecting portion between the first movable member 31 and the second movable member 32 instead of the elastic members 40a, 40b, and 40c, and the flange back and tilt are adjusted by changing the thickness of the spacer members in the optical axis direction. Furthermore, the first movable member 31 may be provided with holes in three locations into which adjustment screws are inserted, and the second movable member 32 may be provided with female threads into which the adjustment screws are threaded.

[0044] 5, balls 36a, 36b, and 36c serving as rolling members are arranged at three locations between the fixed member 21 and the second movable member 32. The balls 36a, 36b, and 36c roll when the second movable member 32 (movable unit 20b) shifts relative to the fixed member 21 (fixed portion 20a), and have the function of guiding the movable unit 20b (maintaining the distance between the fixed member 21 and the second movable member 32 in the optical axis direction).

[0045] 7, a magnet 39 is fixed to the second movable member 32 by adhesive or the like. The magnet 39 generates a magnetic force (attraction force) that acts on the fixed member 21 to move the fixed member 21 closer to the second movable member 32 in the optical axis direction. As a result, the balls 36a, 36b, and 36c are pressed against the fixed member 21 and the second movable member 32.

[0046] The movable unit 20b can freely shift and rotate within the shift surface 12c relative to the fixed member 20a. Therefore, if the shifting and rotation of the movable unit 20b within the shift surface 12c are prevented during the adjustment process of rotating the adjustment screws 41a, 41b, and 41c, the workability of the adjustment process is improved. In this embodiment, as shown in FIGS. 5 to 7 , the first movable member 31 is provided with a positioning hole 31p and a vibration prevention hole 31q as movement prevention parts that prevent the movable unit 20b from moving (including shifting and rotation) within the shift surface 12c relative to the fixed member 21. By engaging a jig (not shown) with the positioning hole 31p and the vibration prevention hole 31q, the flange focal distance and tilt can be adjusted by rotating the adjustment screws 41a, 41b, and 41c while preventing the movable unit 20b from moving within the shift surface 12c.

[0047] The movement preventing portion may be provided on the second movable member 32, and the movement preventing portion may not be a hole, but may be a recess or part of the outer shape of the first or second movable member.

[0048] The first magnetic circuit and first coil 33a form a VCM as a first actuator, the second magnetic circuit and second coil 33b form a VCM as a second actuator, and the third magnetic circuit and third coil 33c form a VCM as a third actuator. A Lorentz force is generated in the first magnetic circuit in a direction perpendicular to the magnetic field generated in the optical axis direction and the current flowing through the first coil 33a, and the resultant direction of the Lorentz force changes depending on the direction of current flow through the first coil 33a. A similar Lorentz force is generated in the second magnetic circuit and second coil 33b, and in the third magnetic circuit and third coil 33c. The first and second actuators generate driving forces that shift the movable unit 20b in the Y direction. The sum of these driving forces generates a driving force in the Y direction, and the difference between these driving forces generates a rotational force around the optical axis. The third actuator generates a driving force that shifts the movable unit 20b in the X direction.

[0049] In sensor vibration isolation device 20 configured as described above, fixed part 20a supports movable unit 20b with three degrees of freedom, and movable unit 20b can translate and rotate relative to fixed part 20a within shift plane 12c. Because movable unit 20b holds imaging element 11, fixed part 20a is fixed to base member 13c, allowing imaging element 11 to translate and rotate within shift plane 12c. In other words, sensor vibration isolation device 20 is configured as an XYθ stage that can control the three-axis drive of imaging element 11.

[0050] 8 shows a YZ cross section of the connecting portion where the first movable member 31 and the second movable member 32 of the movable unit 20b are connected by an adjustment screw 41a with an elastic member 40a sandwiched therebetween. The connecting portions at three locations have the same configuration.

[0051] The first movable member 31 is provided with a female threaded portion 31a into which an adjustment screw 41a screws, and the first movable member 31 is biased so as to move away from the second movable member 32 by the biasing force of an elastic member 40a arranged around the female threaded portion 31a. Rotating the adjustment screw 41a makes it possible to adjust the distance in the optical axis direction between the first movable member 31 (female threaded portion 31a) and the second movable member 32, in other words, the flange focal distance from the mount surface to the image sensor 11. A protrusion 31t is provided on the back surface of the first movable member 31 facing the fixed member 21. When an external force greater than the biasing force of the elastic member 40a is applied, such as when the camera system 10 is dropped in the +Z direction, the protrusion 31t comes into contact with the front surface of the fixed member 21, thereby preventing damage to the first movable member 31 and the image sensor 11 held thereby.

[0052] When no external force is applied, a gap ΔA between the rear end (end on the rear side) of the female thread portion 31a of the first movable member 31 and the opposing front surface of the second movable member 32 and a gap ΔB between the rear end of the protrusion 31t and the front surface of the fixed member 21 have the relationship ΔA<ΔB. Due to this relationship, when adjusting the distance between the first movable member 31 and the second movable member 32 by rotating the adjustment screw 41a to bring them closer, it is possible to ensure an adjustment margin while avoiding interference of the protrusion 31t with the fixed member 21. Note that, as shown in FIG. 7, the protrusions 31t are preferably arranged at the four corners (31t, 31t1, 31t2, 31t3) of the rectangular frame-shaped first movable member 31.

[0053] Next, a description will be given of changes in flange focal length when the movable unit 20b shifts in the sensor vibration isolation device 20. Figures 9(a) to 9(c) show YZ cross sections of the fixed member 21 and the movable unit 20b.

[0054] 9(a) shows the state before flange back adjustment. Inside the package 11d of the image sensor 11, a sensor chip 11b is bonded with a die bond material 11c. The surface of the sensor chip 11b is the imaging surface 11a. Due to warping and tilting caused by manufacturing errors in the sensor chip 11b, the imaging surface 11a is tilted with respect to the shift plane (XY plane).

[0055] 9(b) shows a state in which the imaging plane 11a is made parallel to the shift plane and the flange back is adjusted by adjusting the tilt of the first movable member 31. The flange back at this time is designated as F1.

[0056] FIG. 9(c) shows a state in which the movable unit 20b has shifted by D1 in the +Y direction from the state in FIG. 9(b). The flange back at this time is F2. The movable unit 20b shifts along the fixed member 21, which is parallel to the shift plane, via the balls 36a, 36b, and 36c. For this reason, the position of the movable unit 20b, which has shifted in the +Y direction, in the optical axis direction (Z direction), is unlikely to change. In other words, F1 ≈ F2, and the change in flange back due to the shift of the movable unit 20b is kept small. The same is true when the movable unit 20b is rotating.

[0057] Next, we will explain the change in flange focal length when the movable unit 920b shifts in a sensor vibration isolation device 920 as a comparative example. Figures 12(a) to 12(c) show the YZ cross section of the fixed member 921 and movable unit 920b in the comparative example. In this sensor vibration isolation device 920, the first movable member 931 and the second movable member 932 are integrated (fixed) so that the distance between them in the optical axis direction cannot be adjusted. The fixed member 921 is also connected to the camera body 913a via elastic members 940a and 940b. By rotating an adjustment screw (not shown), flange focal length adjustment can be performed by adjusting the positions of the fixed member 921 and movable unit 920b together in the optical axis direction, and tilt adjustment can be performed together with respect to the shift plane (XY plane).

[0058] 12(a) shows the state before flange back adjustment. A sensor chip 911b is attached to the inside of a package 911d of an image sensor 911 with a die bond material 911c. The surface of the sensor chip 911b is the imaging surface 911a. Due to warping and tilting caused by manufacturing errors in the sensor chip 911b, the imaging surface 911a is tilted with respect to the shift plane.

[0059] 12(b) shows a state in which the imaging surface 911a is parallel to the shift plane and the flange back is adjusted by adjusting the tilt of the fixed member 921 and the movable unit 920b. The flange back at this time is designated as F91. The fixed member 921 is tilted with respect to the shift plane due to the tilt adjustment.

[0060] FIG. 12(c) shows a state in which movable unit 920b has shifted by D1 in the +Y direction from the state in FIG. 12(b). The flange focal distance at this time is F92. In this comparative example, movable unit 920b shifts along fixed member 921, which is inclined with respect to the shift plane, via balls 936a and 936b (and 936c, not shown). As a result, the position of movable unit 920b, which has shifted in the +Y direction, in the optical axis direction changes. In other words, F91≠F2, and the change in flange focal distance due to the shift of movable unit 920b is greater than in this embodiment.

[0061] As explained above, in this embodiment, the position of the first movable member 31 that holds the imaging element 11 is adjusted during flange focal length adjustment without changing the position of the fixed member 21. This makes it possible to make the sensor vibration isolation device 20, including the adjustment mechanism and adjustment allowance, more compact than when adjusting the position of the entire sensor vibration isolation device. Furthermore, even if the movable unit 20b is shifted or rotated, changes in the position of the imaging surface 11a in the optical axis direction, that is, changes in the flange focal length, can be suppressed. [Example]

[0062] Next, a second embodiment will be described. Fig. 10 shows an exploded view of the internal configuration of a camera 10a' of the second embodiment as seen from the rear side. In this embodiment, the configuration relating to heat dissipation of the sensor vibration isolation device 220 will be described. Components in this embodiment that are common to or equivalent to those in the first embodiment are given reference numerals that are 200 larger than the reference numerals in the first embodiment.

[0063] Inside camera 10a, there are arranged base member 213c, shutter member 340, main frame 350, and main board 360. Shutter member 340 opens and closes a shutter opening by moving shutter curtain 342, thereby controlling the amount of exposure of image sensor 211. Shutter member 340 is fixed to base member 13c by screws 345a, 345b, and 345c inserted into holes 341a, 341b, and 341c provided in three locations on shutter member 340 and fastened into first screw holes 331a, 331b, and 331c provided in three locations on base member 213c.

[0064] Holes 630a, 630b, 630c, and 630d are formed in fixing member 221 of sensor vibration isolation device 220 at positions corresponding to the four second screw holes 332a, 332b, 332c, and 332d of base member 213c. Fixing member 221 is fixed to base member 213c by fastening fixing screws 631a, 631b, 631c, and 631d inserted into holes 630a, 630b, 630c, and 630d into second screw holes 332a, 332b, 332c, and 332d.

[0065] Main frame 350 is a sheet metal member made of a metal (stainless steel, aluminum, carbon steel, copper, etc.) with high thermal conductivity. Holes 352a, 352b, 352c, and 352d are formed in four places on main frame 350. Main frame 350 has the function of diffusing and dissipating heat generated within camera 10a′.

[0066] An electronic circuit is formed on the main board 360. Various electronic components such as a CPU 364 and a card connector 369 are mounted on the surface of the main board 360. A plurality of connectors 365, 366a, 366b, 367a, 367b, and 368 are also mounted on the main board 360. The connectors 367a, 367b, 367c, and 368 are electrically connected to an FPC 237 that is connected to the imaging element 211 and transmits imaging signals, and a drive FPC 235 that drives the actuator.

[0067] Furthermore, holes 362a, 362b, 362c, and 362d are formed in four locations on main board 360. Screws 363a, 363b, 363c, and 363d are inserted into holes 362a to 362d and holes 352a to 352d of main frame 350. Main board 360 is fixed to base member 213c together with main frame 350 by fastening screws 363a to 363d into four third screw holes 333a, 333b, 333c, and 333d in base member 213c. In this way, main frame 350, together with base member 213c, constitutes the main body of camera 10a′.

[0068] In this embodiment, a first cylindrical member 223a, a second cylindrical member 223b, and a third cylindrical member 223c are arranged as heat transfer members between the main frame 350 and the fixing member 221 of the sensor vibration isolation device 220. The first to third cylindrical members 223a to 223c of the main frame 150 are formed of a metal with high thermal conductivity. The fixing member 221 is fixed to the main frame 350 by fastening screws 242a, 242b, and 242c inserted into holes 353a, 353b, and 353c of the main frame 350 and the first to third cylindrical members 223a to 223c into screw holes 623a, 623b, and 623c of the fixing member 221.

[0069] An FPC 346 and lead wires 347a and 347b for driving the shutter are attached to the shutter member 340, and these are respectively connected to connectors 365, 366a and 366b on the main board 360. This allows signals and power to be transmitted between the main board 360 and the shutter member 340.

[0070] Fig. 11(a) shows the configuration on the +Z side of the main frame 350 as viewed from the rear. Fig. 11(b) shows a cross section taken along line AA in Fig. 11(a), and Fig. 11(c) shows a cross section taken along line BB in Fig. 11(a). It is desirable for the camera 10a' to have a configuration that can efficiently dissipate heat generated by the imaging element 211.

[0071] However, with conventional configurations in which flange focal length adjustment is performed by moving the entire fixed member and movable unit relative to the camera body, it is difficult to create a heat dissipation path from the sensor vibration isolation device to the body. In other words, with conventional configurations, the sensor vibration isolation device is only thermally connected to the body with adjustment screws in three locations.

[0072] In contrast to this, in this embodiment, the fixing member 221 of the sensor vibration isolation device 220 does not move during flange back adjustment, as in embodiment 1. Therefore, in addition to the three fixing screws 631a to 631c that thermally connect the fixing member 221 to the main body (base member 213c) as in the conventional case, a fourth fixing screw 631d can be added. That is, with the sensor vibration isolation device 220 of this embodiment, it is possible to increase the number of locations where the fixing member 221 is thermally connected to the base member 213c by fastening with screws to more than three locations, thereby increasing the number of heat dissipation paths from the sensor vibration isolation device 220 to the base member 213c.

[0073] 11(b) and 11(c), a method for fixing the fixing member 221 of the sensor vibration isolation device 220 to the main frame 350 will be described. Because the fixing member 221 does not move during flange back adjustment, it is possible to improve the positional accuracy in the Z direction relative to the base member 213c. Similarly, because the positional accuracy in the Z direction of the main frame 350 relative to the base member 213c can be improved, it is possible to thermally connect the fixing member 221 to the main frame 350 via the first to third cylindrical members 223a to 223c and the screws 242a to 242c. Therefore, it is possible to increase the heat dissipation path from the fixing member 221 to the main frame 350, to which heat from the imaging element 211 is transferred.

[0074] Furthermore, since the fixed member 221 does not move relative to the base member 213c during flange back adjustment, it is possible to achieve high precision in the distance in the optical axis direction between the magnets 226a, 226b, and 226c fixed to the fixed member 221 and the main frame 350. Therefore, it is possible to form three magnetic circuits by the magnets 226a to 226c fixed to the fixed member 221 and the yoke serving as the main frame 350.

[0075] When forming a magnetic circuit using main frame 350 as a yoke in this way, it is preferable that the material of main frame 350 be a magnetic material such as carbon steel. Giving main frame 350 both a heat dissipation function and a yoke function makes it possible to reduce the number of parts in camera 10a' and to make it thinner in the optical axis direction.

[0076] As explained above, according to this embodiment, it is possible to increase the number of heat dissipation paths from the sensor vibration isolation device 220, which includes the image sensor 211, which is a heat source, to the main body of the camera 10a', and to efficiently dissipate the heat generated by the image sensor 211.

[0077] The above embodiment includes the following configurations. (Configuration 1) a fixing member fixed to a main body of the optical device; a movable unit that holds an optical element and is movable in a first direction relative to the fixed member; an actuator that drives the movable unit in the first direction relative to the fixed member, The movable unit is a first movable member that holds the optical element; a second movable member connected to the first movable member and receiving a driving force from the actuator; an adjustment mechanism that adjusts the position of the first movable member relative to the second movable member in a second direction perpendicular to the first direction. (Configuration 2) the adjustment mechanism includes an adjustment screw that is held by one of the first and second movable members and that screws into the other of the first and second movable members; 2. The optical element driving device according to configuration 1, wherein the position adjustment is performed by rotating the adjustment screw. (Configuration 3) 3. The optical element driving device according to configuration 2, wherein the adjustment mechanism includes an elastic member disposed between the first movable member and the second movable member. (Configuration 4) The optical element driving device of any one of configurations 1 to 3, characterized in that the first movable member and the second movable member are arranged on opposite sides of the fixed member in the second direction. (Configuration 5) the actuator includes a magnet and a coil; 5. The optical element driving device according to any one of configurations 1 to 4, wherein one of the magnet and the coil is held by the fixed member, and the other is held by the second movable member. (Configuration 6) An optical element driving device described in any one of configurations 1 to 5, characterized in that a rolling member that rolls as the movable unit moves in the first direction is arranged between the fixed member and the first or second movable member. (Configuration 7) The optical element driving device according to any one of configurations 1 to 6, wherein the movable unit has a movement preventing portion that prevents movement of the movable unit relative to the fixed member in a plane perpendicular to the second direction during the position adjustment. (Configuration 8) the actuator includes a magnet, a coil, and a yoke; The optical element driving device described in any one of configurations 1 to 7, characterized in that the yoke fixed to the fixed member is arranged on the opposite side of the fixed member across the second movable member in the second direction. (Configuration 9) the adjustment mechanism adjusts the position of the first movable member at a plurality of adjustment points; 9. The optical element driving device according to any one of configurations 1 to 8, wherein the number of points at which the fixing member is fixed to the main body is greater than the number of the plurality of adjustment points. (Configuration 10) 10. The optical element driving device according to any one of configurations 1 to 9, wherein the optical element is an imaging element. (Configuration 11) 11. An optical device comprising the optical element driving device according to any one of configurations 1 to 10.

[0078] The embodiments described above are merely representative examples, and various modifications and alterations are possible to each embodiment when implementing the present invention. [Explanation of symbols]

[0079] 10a, 10a′ Camera 11,211 image sensors 20,220 Sensor vibration isolation device 20b Mobile unit 21,221 Fixing member 31,231 First moving member 32,232 Second movable member 41a, 41b, 41c, 241a, 241b, 241c Adjustment screws

Claims

1. a fixing member fixed to a main body of the optical device; a movable unit that holds an optical element and is movable in a first direction relative to the fixed member; an actuator that drives the movable unit in the first direction relative to the fixed member, The movable unit is a first movable member that holds the optical element; a second movable member connected to the first movable member and receiving a driving force from the actuator; an adjustment mechanism that adjusts the position of the first movable member relative to the second movable member in a second direction perpendicular to the first direction.

2. the adjustment mechanism includes an adjustment screw that is held by one of the first and second movable members and that screws into the other of the first and second movable members; 2. The optical element driving device according to claim 1, wherein the position adjustment is performed by rotating the adjustment screw.

3. 3. The optical element driving device according to claim 2, wherein the adjustment mechanism includes an elastic member disposed between the first movable member and the second movable member.

4. 2. The optical element driving device according to claim 1, wherein the first movable member and the second movable member are arranged on opposite sides of the fixed member in the second direction.

5. the actuator includes a magnet and a coil; 2. The optical element driving device according to claim 1, wherein one of the magnet and the coil is held by the fixed member, and the other is held by the second movable member.

6. 2. The optical element driving device according to claim 1, wherein a rolling member that rolls as the movable unit moves in the first direction is disposed between the fixed member and the first or second movable member.

7. 2. The optical element driving device according to claim 1, wherein the movable unit has a movement prevention portion that prevents movement of the movable unit relative to the fixed member in a plane perpendicular to the second direction during the position adjustment.

8. the actuator includes a magnet, a coil, and a yoke; 2. The optical element driving device according to claim 1, wherein the yoke is fixed to the fixed member and is disposed on the opposite side of the fixed member across the second movable member in the second direction.

9. the adjustment mechanism adjusts the position of the first movable member at a plurality of adjustment points; 2. The optical element driving device according to claim 1, wherein the number of points at which the fixing member is fixed to the main body is greater than the number of the plurality of adjustment points.

10. 2. The optical element driving device according to claim 1, wherein the optical element is an image pickup element.

11. An optical device comprising the optical element driving device according to any one of claims 1 to 10.

Images