Optical apparatus, image stabilizing device, lens barrel, and image pickup apparatus

Abstract

Provided is an optical device, an image stabilizing apparatus, a lens barrel, and an image pickup apparatus, which can adjust the position of a lens with a simple configuration that enables miniaturization without degrading optical performance. A lens group is disposed on an optical axis in a manner movable along the optical axis. A first shaft is disposed parallel to the optical axis and has a first fixed portion and a fitting portion fitted in a predetermined lens group. A support member rotatably supports the first shaft by holding the first fixed portion. A central axis of the first fixed portion is eccentric from a central axis of the fitting portion. The first shaft is supported by the support member so as to be rotatable around the central axis of the first fixed portion. The predetermined lens group is movable between an image pickup position on the optical axis and a retreat position away from the optical axis by rotation around the first shaft.

Description

Technical Field

[0001] This invention relates to optical equipment, image stabilization devices, lens barrels, and camera equipment. Background Technology

[0002] In recent years, there has been a demand for improved portability of optical devices such as digital cameras, camcorders, and interchangeable lens barrels when not in use. As one technique for miniaturizing optical devices when not in use, a retraction mechanism that shortens the distance between lenses along the optical axis is known. Additionally, as another technique, a lens retraction mechanism that shortens the overall length by retracting a portion of the lens group in a direction perpendicular to the optical axis (radial) is known.

[0003] For example, Japanese Patent Application Publication No. 2004-233919A discloses a camera device that precisely drives a retractable lens assembly that can rotate around an axis parallel to the optical axis between an imaging position on the optical axis and a retractable position outside the optical axis, and can be easily adjusted in position. Japanese Patent Application Publication No. 2015-021993A discloses a camera device that provides a guide member that moves a movable member in a direction perpendicular to the optical axis. The camera device is miniaturized by retracting the movable member from the optical axis when not in use and by storing another member in the space occupied by the movable member when in use.

[0004] Japanese Patent Application Publication No. 2007-033961A discloses a lens driving device that, upon retraction, utilizes a bending retraction mechanism to move at least one lens frame from an imaging position on the optical axis to a retracted position outside the optical axis. Japanese Patent Application Publication No. 2006-171079A discloses an interchangeable lens in which a retractable lens barrel, which holds part of the optical system, is configured to retract to a retracted position outside the optical axis, and a light intensity adjustment unit is configured on the optical axis in a manner movable along the optical axis direction.

[0005] Because the technology disclosed in JP 2004-233919A uses three eccentric pins to adjust the drive unit of the retractable lens group, a longer adjustment time is required and the lens barrel is enlarged due to the complexity of the retraction mechanism. The technology disclosed in JP 2015-021993A does not adjust the movable member along the optical axis in the retracted position. Therefore, when a heavy, large lens in the retracted position is subjected to an external impact, for example, the lens positional accuracy after returning to the working position may decrease, which may degrade optical performance. As disclosed in JP 2007-033961A and JP 2006-171079A, when the lens rotates from its position on the optical axis to the retracted position about an axis perpendicular to the optical axis, the outer diameter of the lens barrel tends to increase to prevent unwanted light from incident on the image sensor during imaging, thus enlarging the lens barrel. Summary of the Invention

[0006] The present invention provides an optical device that can adjust the position of a predetermined lens with a simple construction that enables miniaturization without degrading optical performance.

[0007] Therefore, a first aspect of the present invention provides an optical device comprising: a lens group disposed on the optical axis in a manner movable along the optical axis; a first axis disposed parallel to the optical axis and having a first fixing portion and a fitting portion in a predetermined lens group fitted into the lens group; and a support member rotatably supporting the first axis by holding the first fixing portion, wherein the central axis of the first fixing portion is eccentric to the central axis of the fitting portion, wherein the first axis is supported by the support member in a manner rotatable about the central axis of the first fixing portion, and wherein the predetermined lens group is movable between an imaging position on the optical axis and a retracted position away from the optical axis by rotating about the first axis.

[0008] According to the present invention, an optical device can be provided that allows for adjusting the position of a predetermined lens with a simple construction that enables miniaturization without degrading optical performance.

[0009] Other features of the invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0010] Figure 1A and Figure 1B These are perspective views showing the appearance of the digital camera and its lens barrel according to the first embodiment.

[0011] Figure 2 This is a cross-sectional view showing the extended state of the lens barrel according to the first embodiment.

[0012] Figure 3This is a cross-sectional view showing the retracted state of the lens barrel according to the first embodiment.

[0013] Figure 4A and Figure 4B This is a perspective view showing an image stabilization device installed in the lens barrel according to the first embodiment.

[0014] Figure 5A and Figure 5B This is a front view showing the structure of the image stabilization device in the first embodiment.

[0015] Figure 6 This is a rear view showing the structure of the image stabilization device in the first embodiment.

[0016] Figure 7A and Figure 7B This is a perspective view showing the third set of retaining members constituting the image stabilization device in the first embodiment in the states of the camera position and the retracted position, respectively.

[0017] Figure 8 This is a perspective view showing the relationship between the third set of substrates and the third set of levers constituting the image stabilization device in the first embodiment.

[0018] Figure 9 It is along Figure 6 The image stabilization device is shown in a cross-sectional view taken by line CC.

[0019] Figure 10 It is along Figure 5A The image stabilization device is shown in a cross-sectional view taken by line AA.

[0020] Figure 11 It is along Figure 6 The image stabilization device is shown as a cross-sectional view taken by line BB.

[0021] Figure 12 This is a schematic diagram showing the relationship between the third lens group, the retaining member axis, and the contact axis that constitute the image stabilization device in the first embodiment.

[0022] Figure 13A and Figure 13B This is a perspective view showing the appearance of a digital camera according to the second embodiment.

[0023] Figure 14 This is a block diagram schematically illustrating the construction of a digital camera according to the second embodiment.

[0024] Figure 15 This is a cross-sectional view showing the state of the wide-angle end of the lens barrel in the second embodiment.

[0025] Figure 16This is a cross-sectional view showing the state of the telephoto end of the lens tube in the second embodiment.

[0026] Figure 17 This is a cross-sectional view showing the retracted state of the lens barrel in the second embodiment.

[0027] Figure 18 This is an exploded perspective view showing the structure of the image stabilization device in the second embodiment.

[0028] Figure 19 This is a front view showing the camera state of the image stabilization device in the first embodiment.

[0029] Figure 20 This is a front view showing the non-camera state of the image stabilization device according to the second embodiment.

[0030] Figure 21 It is along Figure 20 The line DD shown is a first cross-sectional view of the image stabilization device.

[0031] Figure 22 It is along Figure 20 The line DD shown is a second cross-sectional view of the image stabilization device.

[0032] Figure 23 This is an exploded perspective view showing the structure of the image stabilization device according to the third embodiment.

[0033] Figure 24 This is a front view showing the camera state of the image stabilization device in the third embodiment.

[0034] Figure 25 This is a front view showing the non-camera state of the image stabilization device according to the third embodiment.

[0035] Figure 26 It is along Figure 25 The line EE shown is a cross-sectional view of the image stabilization device.

[0036] Figure 27 This is a block diagram schematically illustrating the construction of a digital camera according to the fourth embodiment.

[0037] Figure 28 This is a cross-sectional view showing the state of the wide-angle end of the lens barrel in the fourth embodiment.

[0038] Figure 29 This is a cross-sectional view showing the state of the telephoto end of the lens tube in the fourth embodiment.

[0039] Figure 30 This is a cross-sectional view showing the retracted state of the lens barrel in the fourth embodiment.

[0040] Figure 31A and Figure 31B These are cross-sectional and perspective views showing the imaging state (telephoto end state) of the lens barrel in the fourth embodiment.

[0041] Figure 32A and Figure 32B These are cross-sectional and perspective views showing the first stage of the lens barrel transitioning from a camera state to a non-camera state in the fourth embodiment.

[0042] Figure 33A and Figure 33B These are cross-sectional and perspective views showing the second stage of the lens barrel transitioning from a camera state to a non-camera state in the fourth embodiment.

[0043] Figure 34A and Figure 34B These are cross-sectional and perspective views showing the lens barrel in the non-photographic state (retracted state) of the fourth embodiment.

[0044] Figure 35 This is a timing diagram showing the movement of the lens group and aperture unit during the transition of the lens barrel from the imaging state to the non-imaging state in the fourth embodiment. Detailed Implementation

[0045] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following embodiments, a camera device such as a digital camera or digital video camera is used as the optical device according to the present invention. In particular, the lens barrel of the camera device will be described primarily. It should be noted that the lens barrel may be an interchangeable lens that can be detached from the main body of the camera device or may be non-detachable (i.e., it may be integrally formed with the main body of the camera device).

[0046] Figure 1A This is a schematic perspective view of the appearance of a digital camera 100 according to a first embodiment. The digital camera 100 is provided with a camera body 101 and a retractable zoom lens barrel 102 (hereinafter referred to as "lens barrel 102") disposed on the front side of the camera body 101. Figure 1B This is a perspective view showing the external appearance of the lens barrel 102. The lens barrel 102 is provided with a zoom driver (zoom actuator) 31 that performs the extension and retraction actions.

[0047] When the power to the camera body 101 is turned on, the lens barrel 102 extends, changing from a retracted (collapsed) state to an extended state. In the extended state, the various lens groups included in the lens barrel 102 are arranged on the imaging optical axis (hereinafter referred to as the "optical axis"). Therefore, the imaging operation of the digital camera 100 becomes available. Furthermore, the lens barrel 102 is configured such that, in the extended state, the magnification can be changed by controlling the position of the lens groups in the optical axis direction. When the power to the camera body 101 is turned off, the lens barrel 102 retracts, changing from the extended state to the retracted state.

[0048] Figure 2 This is a cross-sectional view showing the lens barrel 102 in its extended state, including the optical axis. Figure 3 This is a cross-sectional view showing the lens barrel 102 in its retracted state, including the optical axis. Figure 2 and Figure 3 In the middle, the left side is the subject (not shown), and the right side is the camera body 101.

[0049] The lens barrel 102 is provided with a first lens group 23, a first set of retaining members 24a for holding the first lens group 23, a first set of barrels 24b for holding the first set of retaining members 24a, a second lens group 25, and a second set of retaining members 26 for holding the second lens group 25. Additionally, the lens barrel 102 is provided with a third lens group 2, a third set of retaining members 3 for holding the third lens group 2, a fourth lens group 27, a fourth set of retaining members 28 for holding the fourth lens group 27, a fifth lens group 29, and a sensor retaining member 30 for holding the fifth lens group 29.

[0050] The first lens group 23, the first retaining member 24a, and the first barrel 24b constitute the first unit. The second lens group 25 and the second retaining member 26 constitute the second unit. The third lens group 2 and the third retaining member 3 constitute the third unit. The fourth lens group 27 and the fourth retaining member 28 constitute the fourth unit. The fifth lens group 29 and the sensor retaining member 30 constitute the fifth unit. The imaging optical system in the lens barrel 102 is composed of the first lens group 23, the second lens group 25, the third lens group 2, the fourth lens group 27, and the fifth lens group 29.

[0051] The shutter unit 32 is positioned between the second and third groups of units. The shutter unit 32 adjusts the subject beam imaged onto the image sensor 36 by moving a pair of shutter blades (not shown) in a plane perpendicular to the optical axis between a position where the blades block the light path and a position where the blades retract from the light path. It should be noted that in the case of a digital SLR camera with interchangeable lenses, the shutter unit is located within the camera body.

[0052] The sensor holder 30 supports the focus driver (not shown) and the zoom driver 31. Focusing is performed by moving the fourth set of holders 28, which holds the fourth lens group 27, in the optical axis direction using the focus driver. Zooming is performed by moving the first, second, and third sets of units in the optical axis direction using the zoom actuator 31.

[0053] The zoom mechanism will be described below. A fixed cylinder 22 is disposed on the outermost periphery of the lens barrel 102. Three cam grooves 22a are formed at nearly equal intervals along the circumferential direction in the inner periphery of the fixed cylinder 22. Furthermore, three straight-line keyways 22b are formed at nearly equal intervals along the circumferential direction in the inner periphery of the fixed cylinder 22. An outer cam cylinder 34 is disposed inside the fixed cylinder 22. Three followers (not shown) are formed at nearly equal intervals along the circumferential direction on the outer periphery of the outer cam cylinder 34. The three followers of the outer cam cylinder 34 are slidably engaged with the three cam grooves 22a of the fixed cylinder 22. A zoom driver 31 rotates the outer cam cylinder 34. When the outer cam cylinder 34 rotates via the zoom driver 31, it rotates relative to the fixed cylinder 22 while moving along the lift of the cam grooves 22a in the optical axis direction.

[0054] The outer straight-in cylinder 35 is disposed inside the outer cam cylinder 34. A straight-in keyway 35a is formed in the inner circumference of the outer straight-in cylinder 35, and a circumferential groove 35b is formed in the outer circumference of the outer straight-in cylinder 35. At predetermined intervals along the circumferential direction and optical axis direction, bayonet claws (not shown) are formed on the inner circumference of the outer cam cylinder 34, respectively engaging with the circumferential grooves 35b formed in the outer circumference of the outer straight-in cylinder 35. Additionally, straight-in keys (not shown) that engage with the straight-in keyways 22b of the fixed cylinder 22 are formed on the outer circumference of the outer straight-in cylinder 35. Therefore, when the outer cam cylinder 34 rotates, the outer straight-in cylinder 35 moves linearly along the straight-in keyways 22b of the fixed cylinder 22 in the optical axis direction.

[0055] The inner cam cover 33 is disposed inside the outer straight-in cylinder 35, and the inner cam cylinder 20 is disposed inside the inner cam cover 33. Three cam grooves 20a, three shutter cam grooves 20b, and three second-group cam grooves 20c are formed at nearly equal intervals along the circumferential direction on the inner circumference of the inner cam cylinder 20. Three first-group cam grooves 20d are formed at nearly equal intervals along the circumferential direction on the outer circumference of the inner cam cylinder 20.

[0056] Three followers, three inner cam cover engagement portions, and three drive keys (not shown) are formed at nearly equal intervals along the circumferential direction on the outer periphery of the inner cam cylinder 20. Three engagement claws (not shown) engaging with the inner cam cover engagement portions of the inner cam cylinder 20, and three ratchet portions (not shown) engaging with the drive keys of the inner cam cylinder 20, are formed in the inner cam cover 33. Furthermore, the drive keys provided on the outer periphery of the inner cam cylinder 20 engage with three keyways (not shown) provided on the inner periphery of the outer cam cylinder 34. Therefore, the inner cam cylinder 20 rotates around the optical axis with the same phase as the outer cam cylinder 34. As the inner cam cylinder 20 rotates, the inner cam cover 33 moves along the optical axis direction while rotating integrally with the inner cam cylinder 20 around the optical axis.

[0057] The inner cam cylinder 20 holds the straight-through cylinder 21 in an inner circumference in a manner that allows it to rotate relative to the inner cam cylinder 20. The straight-through plate 19 is integrally attached to the straight-through cylinder 21. Straight-through keys (not shown) that engage with the straight-through keyway 35a provided on the inner circumference of the outer straight-through cylinder 35 are formed in the straight-through plate 19. Additionally, a first set of guide keys 21b, a second set of guide grooves (not shown), and a third set of guide grooves 21d are formed in the straight-through cylinder 21. Furthermore, a third set of levers 6 (see...) can be used... Figure 4A and Figure 4B A retraction guide surface (not shown), a retraction completion surface (not shown) that can contact the third set of levers 6, and a flange (not shown) are formed on the straight-in cylinder 21. The straight-in cylinder 21 is held by the flange and the straight-in plate 19 of the straight-in cylinder 21 in a rotatable manner and can move integrally with the inner cam cylinder 20 along the optical axis.

[0058] The first set of followers (not shown) are arranged at nearly equal intervals at six positions on the inner circumference of the first set of cylinders 24b in the circumferential direction. The first set of retainers 24a and the first set of cylinders 24b are moved integrally in the optical axis direction by engaging the first set of followers at the six positions with the first set of cam grooves 20d formed at the six positions on the outer circumference of the inner cam cylinder 20 in a slidable manner and by being guided by the first set of guide keys 21b of the straight-in cylinder 21.

[0059] The second set of followers (not shown) are arranged at nearly equal intervals at three positions on the outer periphery of the second set of retainers 26 in the circumferential direction. The second set of retainers 26 is supported in a manner movable along the optical axis by engaging the second set of cam grooves 20c arranged at three positions on the inner periphery of the inner cam cylinder 20 in a slidable manner with the second set of guide grooves (not shown) arranged by the straight-in cylinder 21.

[0060] The shutter follower 32a is disposed at three positions on the outer periphery of the shutter unit 32 at nearly equal intervals in the circumferential direction. By slidably engaging the shutter follower 32a at the three positions with the shutter cam grooves 20b at the three positions on the inner periphery of the inner cam cylinder 20 and being guided by the third set of guide grooves 21d of the straight-in cylinder 21, the shutter unit 32 is supported in a manner that allows it to move along the optical axis.

[0061] Next, the image stabilization device built into the lens barrel 102 will be described. Figure 4A This is a perspective view showing the image stabilization device installed in the lens barrel 102 as viewed from the front side (subject side). Figure 4B This is a perspective view of the image stabilization device as seen from the rear side (image sensor 36 side). The image stabilization device includes a third lens group 2, a third retainer 3, a retainer torsion spring 4, a retainer shaft 50, a contact shaft 80, a third lever 6, a third frame 8, and a third substrate 9.

[0062] The third set of flexible substrates 11 is held by a Hall sensor holder 12, and the Hall sensor holder 12 is fixed to the third set of substrates 9. A pair of Hall elements (not shown) are implemented in the third set of flexible substrates 11. The pair of Hall elements are arranged facing a pair of magnets 8d along the optical axis (see Figure 7A and Figure 7B The position of the camera controller 232 is used to detect changes in the direction and magnitude of the magnetic force of the pair of magnets 8d. Figure 14 Based on the direction and magnitude of the magnetic force detected by the Hall element, the position of the third frame 8 relative to the Hall sensor holder 12 is determined.

[0063] Figure 5A This is a front view (viewed from the subject side) of the image stabilization device with the lens barrel 102 in the extended state. Figure 5B This is a front view showing the image stabilization device with the lens barrel 102 in the retracted state. Figure 6 This is a rear view of the image stabilization device with the lens barrel 102 in the extended state.

[0064] The third retaining element 3 holds the third lens group 2. The third lens group 2 is a retractable lens group, positioned on the optical axis when the lens barrel 102 is in the extended state (hereinafter referred to as the "image-capturing position") and positioned away from the optical axis when the lens barrel 102 is in the retracted state (hereinafter referred to as the "retractable position"). Figure 3As shown, when the lens barrel 102 is retracted, the total length of the lens barrel 102 in the retracted state can be shortened because the distance in the optical axis direction between the second lens group 25 and the fourth lens group 27 can be shortened by moving the third lens group 2 to the retracted position.

[0065] In the description of this embodiment, for convenience, when the third lens group 2 is in the imaging position, the third holding member 3 is indicated as being in the imaging position, and when the third lens group 2 is in the retracted position, the third holding member 3 is indicated as being in the retracted position.

[0066] The third set of retaining members 3 has a third set of masks 17a on the subject side and a third set of masks 17b on the image plane side (see [reference]). Figure 7B ). Three positions of the third frame 8 are formed for hooking the thrust spring 14 (see Figure 7A and Figure 7B A spring hook 8c is located at one end of the third lens group 2. Additionally, a bearing 8a supporting the retaining member shaft 50 (first shaft) is disposed in the third frame 8. The third frame 8 is a support member that rotatably supports the third retaining member 3; specifically, the third retaining member 3 is supported by the bearing 8a disposed in the third frame 8 in a manner that allows it to rotate around the retaining member shaft 50. The third retaining member 3 is configured to move integrally with the third lens group 2 around the retaining member shaft 50 in a plane perpendicular to the optical axis between the imaging position and the retracted position.

[0067] Figure 7A It is a perspective view from the rear side showing the positional relationship between the third set of retainers 3, the third set of frames 8, and the third set of levers 6 when the third set of retainers 3 is in the camera position. Figure 7B This is a perspective view from the rear side showing the positional relationship between the third set of retainers 3, the third set of frames 8, and the third set of levers 6 with the third set of retainers 3 in the retracted position.

[0068] One end of the thrust spring 14 is hooked onto spring hooks 8c formed at three positions on the third set of frames 8. These hooks contact three balls 13 respectively (see...). Figure 8 The three ball receiving surfaces 8b are formed on the third set of frames 8. In addition, the pair of magnets 8d are attached to the third set of frames 8 at positions approximately 90 degrees apart along the circumferential direction in a plane perpendicular to the optical axis.

[0069] Figure 8 This is a perspective view from the front side showing the positional relationship between the third set of substrates 9 and the third set of levers 6. The third set of retainers 3 (not shown) is in the retracted position. Figure 9 It is along Figure 6The cross-sectional view of the third frame 8 is shown by line CC. Ball holes 9a are formed at three locations on the third substrate 9, and balls 13 (rolling members) are disposed in each ball hole 9a. Spring hooks 9b are provided at three locations on the third substrate 9, each hooking the other end of a thrust spring 14. Under the force of the thrust springs 14, with the balls 13a clamped between the ball receiving surface 8b of the third frame 8 and the ball holes 9a of the third substrate 9, the three balls 13 can roll within the ball holes 9a in a plane perpendicular to the optical axis.

[0070] In the third set of base plates 9, there is a third set of lever shafts 7, a bearing 9d supporting the third set of lever shafts 7, and a cam groove 20a of the inner cam cylinder 20 (see...). Figure 2 and Figure 3 A slidably engaged follower 9e. Additionally, in the third substrate 9, a pair of coils 9c are arranged in phase with the pair of magnets 8d. When current is supplied to the pair of coils 9c, a Lorentz force is generated between the magnetism of the coils 9c and the magnets 8d. The Lorentz force causes the third frame 8 to move relative to the third substrate 9 in a plane perpendicular to the optical axis. At this time, since the third holding member 3 is rotatably supported by the third frame 8, the third holding member 3 moves integrally with the third frame 8. That is, the third lens group 2 held by the third holding member 3 can move integrally with the third frame 8.

[0071] A retraction inclined surface 6c that contacts the retraction guide surface (not shown) of the straight-in cylinder 21 and a retraction completion part 6d that contacts the retraction completion surface (not shown) of the straight-in cylinder 21 are provided in the third set of levers 6. The third set of levers 6 is supported by a bearing 9d of the third set of base plates 9 in a manner that allows it to rotate around the third set of lever shaft 7. The third set of levers 6 is stressed by a lever torsion spring 18 attached around the third set of lever shaft 7 so that it contacts the camera position contact surface (not shown) provided on the third set of base plates 9 in the direction toward the camera position.

[0072] Figure 10 It is along Figure 5A The cross-sectional view of the third frame 8 is shown by line AA. A stop part 3a is provided in the third retainer 3 to adjust the position of the third retainer 3 in the optical axis direction. The stop part 3a contacts the contact shaft 80 (second axis).

[0073] Figure 11 It is along Figure 6The cross-sectional view of the third frame 8 is shown by line BB. The retaining torsion spring 4 consists of a torsion spring portion and a compression spring portion, with the compression spring portion being pushed outward to the sleeve 3b of the third retaining member 3. The torsion spring portion of the retaining torsion spring 4 applies force to the third retaining member 3 towards the third frame 8, causing the stop portion 3a of the third retaining member 3 to contact the contact shaft 80 provided in the third frame 8. That is, the retaining torsion spring 4 applies force to the third lens group 2 (third retaining member 3) in the direction of movement from the retracted position to the imaging position. In addition, the compression spring portion of the retaining torsion spring 4 applies force to the third retaining member 3 towards the subject side in the optical axis direction, causing the end of the sleeve 3b of the third retaining member 3 on the subject side to contact the bearing 8a of the third frame 8 on the subject side.

[0074] The image stabilization device configured as described above consists of a camera controller 232 disposed in the camera body 101. Figure 14 ) control. The camera controller 232 is based on the pitch shake detector 239 and pan shake detector 240 configured in the camera body 101. Figure 14 The voltage applied to the pair of coils 9c is controlled by the amount of jitter output so that the third frame 8 moves in a plane perpendicular to the optical axis. In this way, since the image jitter of the subject image formed on the image sensor 36 by the imaging optical system is corrected by moving the third holding member 3 holding the third lens group 2 integrally with the third frame 8 in the direction of correcting image jitter, still images or video images with reduced image jitter can be obtained.

[0075] Next, the position adjustment mechanism of the third lens group 2 will be explained. For example... Figure 11 As shown, the retaining member shaft 50 is fitted parallel to the optical axis into the sleeve 3b of the third set of retaining members 3. The retaining member shaft 50 has a first fixing part 50a, a fitting part 50b, and a first adjusting part 50c. The first fixing part 50a is held by the third set of frames 8. The fitting part 50b is slidably engaged with the third set of retaining members 3 and becomes the center of rotation when the third set of retaining members 3 is retracted. When adjusting the position of the third lens group 2, an adjusting tool is inserted into the first adjusting part 50c. During this period, as... Figure 10 As shown, the contact shaft 80 has a second fixing part 80a, a contact part 80b and a second adjusting part 80c. The second fixing part 80a is held by a third set of frames 8. When the third set of holding members 3 is in the imaging position, the contact part 80b contacts the stop part 3a. When adjusting the lens, the adjusting tool is inserted into the second adjusting part 80c.

[0076] Figure 12 This is a schematic diagram illustrating the relationship between the third lens group 2, the retaining shaft 50, and the contact shaft 80 in an image stabilization device. Figure 11As shown, the center axis of the first fixing part 50a and the center axis of the fitting part 50b of the retaining member shaft 50 are offset by a distance E. Therefore, when the first adjusting part 50c rotates, the third set of retaining members 3 moves eccentrically, and the center of the third lens group 2 is drawn... Figure 12 The trajectory of the ellipse S1 shown moves.

[0077] In addition, such as Figure 10 As shown, the eccentricity F between the central axis of the second fixing part 80a and the central axis of the contact part 80b of the contact shaft 80 is such that when the second adjusting part 80c rotates, the third set of retaining members 3 moves eccentrically around the retaining member axis 50 while drawing an arc S2. The radius of the arc S2 is the straight line between the retaining member axis 50 and the contact shaft 80, and the center of the arc S2 is the retaining member axis 50.

[0078] The distance F, which is the eccentricity of the contact axis 80, is greater than half the distance E, which is the eccentricity of the retaining axis 50 (F ≥ E / 2). Therefore, rotation of the contact axis 80 allows the central axis of the third lens group 2 to move to any position of the ellipse S1, which is the trajectory of the central axis of the third lens group 2 drawn by rotating the retaining axis 50. In other words, by combining the elliptical movement caused by the rotation of the retaining axis 50 and the circular movement caused by the rotation of the contact axis 80, the third retaining member 3 can move freely in a plane perpendicular to the optical axis.

[0079] Furthermore, a second fixing portion 80a is disposed between the contact portion 80b and the second adjusting portion 80c, and the second fixing portion 80a is closer to the second adjusting portion 80c than the contact portion 80b. Therefore, even when a load is applied to the second adjusting portion 80c during adjustment, adjustment can be performed while keeping the contact shaft 80 in a stable state. Thus, due to the simple structure with only two adjustment positions, miniaturization and cost reduction are achieved, and a lens barrel 102 that can be easily adjusted without compromising optical performance is realized.

[0080] like Figure 12 As shown, the straight line connecting the center of the contact shaft 80 and the center of the retaining shaft 50 is defined as the straight line H. When the straight line H is perpendicular to the normal G passing through the central axis of the third lens group 2 (see...), the line H is... Figure 6 When dividing, the lengths H1 and H2 of the division satisfy the relationship "H1≥H2". In this way, when the ellipticity of the elliptical movement of the third lens group 2 caused by the rotation of the retaining axis 50 increases, the adjustment becomes easier because the elliptical movement of the third lens group 2 is approximately a linear movement parallel to the straight line H.

[0081] Furthermore, the first adjustment section 50c and the second adjustment section 80c are positioned along the optical axis on the imaging surface side of the image sensor 36, rather than on the subject side. In other words, the first adjustment section 50c and the second adjustment section 80c are positioned in the same direction. Therefore, during the manufacturing process of the lens barrel 102, the engagement of the adjustment tool with the first adjustment section 50c and the second adjustment section 80c becomes easier, thus reducing manufacturing costs.

[0082] The third set of frames 8, which holds the retaining shaft 50 and the contact shaft 80 together, is held by the thrust spring 14 (see...). Figure 7A The force is applied towards the image sensor 36 in the optical axis direction relative to the third substrate 9. Therefore, even if a large force is applied to the first adjustment part 50c or the second adjustment part 80c by the engagement of the adjustment tool during the manufacturing process of the lens barrel 102, this large force is applied in the opposite direction to the force applied by the thrust spring 14. Therefore, since this large force does not cause damage such as dents in the ball receiving surface 8b and the ball hole 9a, the ball 13 can roll smoothly, which maintains high optical performance (image stabilization performance).

[0083] Next, the second implementation method will be described. Figure 13A This is a perspective view of the digital camera 200 according to the second embodiment, shown from the front side. Figure 13B This is a perspective view of the digital camera 200 from the rear side. The digital camera 200 has a camera body 210 and a lens barrel 201 (with an interchangeable lens) that can be detached from the camera body 210.

[0084] like Figure 13A As shown, for ease of explanation, the mutually perpendicular XYZ axes are defined for the digital camera 200. The direction of extension (optical axis direction) of the optical axis (hereinafter referred to as the "optical axis") of the imaging optical system built into the lens barrel 201 should be the Z-axis direction. When the Z-axis is parallel to the horizontal direction, the X-axis intersects the Z-axis perpendicularly in the horizontal plane, and the Y-axis intersects the horizontal plane perpendicularly. It should be noted that the X-axis direction is the width direction of the camera body 210, the Y-axis direction is the height direction of the camera body 210, and the Z-axis direction is the front-back direction of the camera body 210. In addition, in the following description, the direction of rotation about the X-axis (where the X-axis is the center of rotation) should be the pitch direction, and the direction of rotation about the Y-axis should be the pan direction.

[0085] The grip 212 used by the user when holding the camera body 210 is provided in a portion of the left side (right side when viewed from the rear side) of the camera body 210. The power operation member 213 is disposed on the upper surface of the camera body 210. When the camera body 210 is in a power-off state and the user performs the power operation member 213 to turn it on, the digital camera 200 is powered on internally and the camera body 210 switches to a powered-on state. When the camera body 210 is in a powered-on state, the camera controller 232 (see...) Figure 14 The pre-defined computer program is executed and the digital camera 200 switches to the recording preparation state. Conversely, when the camera body 210 is powered on and the user performs the power-off operation of the power operation component 213, the camera body 210 switches to the power-off state.

[0086] Mode dial 214, release button 215, and accessory socket 216 are also located on the upper surface of the camera body 210. When the user rotates mode dial 214, the recording mode can be switched. Recording modes include video recording mode for capturing video images, automatic still image shooting mode for automatically obtaining appropriate exposure, and manual still image shooting mode where the user can arbitrarily set recording conditions such as shutter speed and aperture value. Camera controller 232 performs recording preparation operations, such as autofocus and automatic exposure control, in response to a half-press operation of release button 215, and performs recording operations in response to a full-press operation. Accessory socket 216 can be equipped with accessories, such as external flash units.

[0087] The lens barrel 201 is mechanically connected to and electrically connected to the camera interface 217 disposed in the camera body 210 via the lens mount 202. Imaging light from the subject is transmitted to the image sensor 236 (see [link]). Figure 14 The imaging optical system that forms an image of the subject is contained inside the lens barrel 201. A zoom operation ring 203, which can be rotated around the optical axis by the user, is disposed on the outer periphery of the lens barrel 201. When the zoom operation ring 203 is rotated, the zoom lens group constituting the imaging optical system moves to a predetermined position corresponding to the angle of the zoom operation ring 203. Therefore, the user can capture an image at the desired field of view.

[0088] The rear operation member 218 and the display unit 219 are located on the rear of the camera body 210. The rear operation member 218 includes multiple buttons and dials assigned various functions. When the camera body 210 is powered on, and when a still image shooting mode or a video image shooting mode is set, a through image of the subject currently captured by the image sensor 236 is displayed on the display unit 219. Additionally, shooting parameters, such as shutter speed and aperture value, are displayed on the display unit 219. The user can change the shooting parameters to the desired settings by operating the rear operation member 218 while looking at the display. The rear operation member 218 includes a play button for specifying the reproduction of recorded images. When the play button is operated, the recording is stored in the storage unit 233 (see...). Figure 14 The captured image is reproduced and displayed on the display unit 219.

[0089] Figure 14 This is a block diagram showing the electrical and optical structures of the digital camera 200. The camera body 210 is equipped with a power supply 230 that supplies power to both the camera body 210 and the lens barrel 201. Additionally, the camera body 210 has an operation unit 231 that includes a power operation component 213, a mode dial 214, a release button 215, a rear operation component 218, and a touch panel function for a display unit 219. The entire system control of the digital camera 200 is performed through the cooperation of a camera controller 232 located in the camera body 210 and a lens controller 204 located in the lens barrel 201.

[0090] The camera controller 232 reads and runs the computer program stored in the storage unit 233. At this time, the camera controller 232 communicates various control signals and data with the lens controller 204 through the communication terminal of the electrical contact 205 located in the lens interface 202. The electrical contact 205 includes a power supply terminal for supplying power from the power source 230 to the lens barrel 201.

[0091] The imaging optical system housed in the lens barrel 201 includes a zoom lens group 220 connected to the zoom operation ring 203, which changes the field of view by moving it in the direction of the optical axis, and an image stabilization device 600 including a shift lens 222 as an image stabilization element. The image stabilization device 600 reduces image jitter by shifting (moving) the shift lens 222 in any direction in the XY plane perpendicular to the optical axis. Details of the construction of the image stabilization device 600 will be mentioned later.

[0092] Additionally, the camera optical system includes an aperture unit 301 for adjusting the amount of light and a focusing lens group 224 that includes a focusing lens that moves along the optical axis to adjust the focal point. Furthermore, the lens barrel 201 includes an image stabilization driver 251 for driving the image stabilization device 600, an aperture driver 302 for driving the aperture unit 301, and a focusing driver 401 for moving the focusing lens group 224.

[0093] The camera body 210 includes a shutter unit 234, a shutter driver 235, an image sensor 236, an image processor 237, and a camera controller 232. The shutter unit 234 controls the amount of subject light passing through the imaging optical system in the lens barrel 201 and forming an image on the image sensor 236. The image sensor 236 performs photoelectric conversion on the optical image of the subject (subject image) formed on the imaging surface and outputs an imaging signal. The image processor 237 applies various image processing techniques to the imaging signal and generates an image signal. (Note: The last sentence appears to be incomplete and possibly refers to a different camera design.) Figure 13B The description of display unit 219 is provided, so its description is omitted.

[0094] The camera controller 232 controls the focus driver 401 in response to a camera preparation operation (such as a half-press operation of the release button 215) on the operation unit 231. For example, when an autofocus operation is specified, the focus detection unit 238 uses the image signal generated by the image processor 237 to determine the focus state of the subject image formed on the image sensor 236, generates a focus signal, and transmits it to the camera controller 232. Simultaneously, the focus driver 401 transmits information about the current position of the focusing lens group 224 to the camera controller 232. Then, the camera controller 232 calculates the defocus amount by comparing the focus state of the subject image with the current position of the focusing lens group 224, calculates the focus drive amount based on the defocus amount, and transmits the focus drive amount to the lens controller 204. The lens controller 204 uses the obtained focus drive amount to move the focusing lens group 224 to a target position in the optical axis direction via the focus driver 401. Therefore, the defocus of the subject image is corrected, and a state of focus on the subject is achieved.

[0095] The focus driver 401 is equipped with a focus motor (not shown) and an optical interruptor (not shown) for detecting the initial position of the focusing lens group 224. A stepper motor can be used as the focus motor. However, a DC motor with an encoder or an ultrasonic motor (vibration actuator) can be used. Alternatively, a light reflector or brush that contacts a conductive pattern and electrically detects the signal can be used instead of the optical interruptor.

[0096] The camera controller 232 controls the driving of the aperture unit 301 and the shutter unit 234 via the aperture driver 302 and the shutter driver 235 based on the aperture value and shutter speed settings received from the operation unit 231. For example, when an automatic exposure control operation is specified, the camera controller 232 performs metering calculations by receiving a luminance signal generated by the image processor 237. In response to an image capture command operation (such as a full press of the release button 215) on the operation unit 231, the camera controller 232 controls the aperture driver 302 based on the obtained metering calculation results. Simultaneously, the camera controller 232 controls the driving of the shutter unit 234 via the shutter driver 235 to perform exposure processing on the image sensor 236.

[0097] As a detection unit capable of detecting angular jitter caused by user-induced camera shake, the camera body 210 includes a pitch shake detector 239 and a pan shake detector 240. The pitch shake detector 239 uses an angular velocity sensor (vibration gyroscope) or an angular acceleration sensor to detect camera shake in the pitch direction and outputs a shake signal. Similarly, the pan shake detector 240 detects camera shake in the pan direction and outputs a shake signal. The camera controller 232 uses the shake signal obtained from the pitch shake detector 239 to calculate the displacement position of the shift lens 222 in the Y-axis direction to counteract pitch shake. Additionally, the camera controller 232 uses the shake signal obtained from the pan shake detector 240 to calculate the displacement position of the shift lens 222 in the X-axis direction to counteract pan shake. Based on the calculated displacement positions in the pitch and pan directions, the camera controller 232 drives the image stabilization device 600 via the image stabilization driver 251 to move the shift lens 222 to target positions in the X and Y axes. Therefore, image jitter is reduced during exposure and during the display of the through image.

[0098] The lens barrel 201 includes a zoom operation ring 203 for changing the field of view of the camera optical system and a zoom detector 206 for detecting the angle of the zoom operation ring 203. For example, a linear potentiometer is used to construct the zoom detector 206, and the angle of the zoom operation ring 203 operated by the user is detected as an absolute value. The field of view information detected by the zoom detector 206 is transmitted to the lens controller 204 and then reflected in various controls of the camera controller 232. It should be noted that a portion of the above information, along with the captured image (image data), is recorded in the storage unit 233 or a recording medium (not shown).

[0099] Next, we will refer to Figures 15 to 17 Explain the positional relationship between the main components of the lens tube 201. Figures 15 to 17 It shows a YZ cross-sectional view of the digital camera 200 (a cross-sectional view perpendicular to the X-axis), and is shown by a cross-section including the optical axis. Figure 15This shows the state where the lens barrel 201 is set to the wide-angle end on the short focal length side. Figure 16 This shows the telephoto end of the lens barrel 201 set to the telephoto side. Figure 17 This shows the retracted state where the total length of the lens tube 201 is at its shortest.

[0100] Lens barrel 201 employs a six-group configuration as an example of a camera optical system that captures incident light and forms an image on image sensor 236. The camera optical system includes a first lens group 221, a shifting lens 222 (second lens group), an aperture unit 301, a third lens group 223, a focusing lens group 224 (fourth lens group), a fifth lens group 225, and a sixth lens group 226. The first lens group 221 to the fifth lens group 225 correspond to… Figure 14 The zoom lens group 220 is used in the lens barrel 201, and the magnification is changed by moving it along the optical axis between the wide-angle end and the telephoto end. It should be noted that the construction of the lens group does not limit the construction of the imaging optical system of the lens barrel 201. For example, the shift lens 222 and the focusing lens group 224 can also be given other functions. Furthermore, some lens groups from the first lens group 221 to the fifth lens group 225 can remain fixed during zooming.

[0101] The lens barrel 201 has a straight-in guide tube 207 and a cam barrel 208. A cam follower (not shown) is formed on the inner circumference of the cam barrel 208. In addition, the cam barrel 208 is connected to the zoom operating ring 203 by a key (not shown). When the zoom operating ring 203 is rotated, the cam barrel 208 moves along the optical axis while rotating about the optical axis through the slidable engagement of the cam groove and the cam follower.

[0102] The linear guide tube 207 is disposed inside the cam tube 208 and fixed to the lens interface 202 by a fixing tube (not shown). Cam grooves (not shown) are formed at equidistant positions on the outer periphery of the linear guide tube 207. Additionally, linear guide grooves that regulate the rotation of the first lens group 221 to the fifth lens group 225 and guide their linear motion in the optical axis direction are formed at equidistant positions on the inner periphery of the linear guide tube 207. Simultaneously, cam grooves with trajectories having different angles in the rotational direction are formed at equidistant positions in the cam tube 208 corresponding to the first lens group 221 to the fifth lens group 225.

[0103] The first lens group 221 to the fifth lens group 225 are provided with multiple cam followers, which are slidably engaged with the straight guide groove of the straight guide cylinder 207 and the cam groove of the cam cylinder 208. When the zoom operating ring 203 is rotated, the cam cylinder 208 rotates. Relatedly, the first lens group 221 to the fifth lens group 225 move along the optical axis direction while their rotation around the optical axis is controlled.

[0104] The lens barrel 201 has a retraction mechanism (not shown) and a retraction mechanism for the shift lens 222. When the lens barrel 201 (digital camera 200) is not in use, the retraction mechanism further retracts the first lens group 221, the third lens group 223, the fourth lens group 224, and the fifth lens group 225 toward the rear side (camera body 210 side), and the retraction mechanism moves the shift lens 222 to a retracted position outside the optical axis. Therefore, portability is improved by shortening the overall length of the lens barrel 201. When the lens barrel 201 is set to the wide-angle end... Figure 15 In the shown configuration, the distance between the first lens group 221 and the shifting lens 222 is relatively large. This is when the lens barrel 201 is set to the telephoto end. Figure 16 In the shown configuration, the distance between the fifth lens group 225 and the sixth lens group 226 is relatively large. The retraction mechanism shortens the total length of the lens barrel 201 along the optical axis when not in use by moving the lens groups, which are configured at a predetermined distance during use, to a closer receiving position.

[0105] like Figure 17 As shown, when the lens barrel 201 is in the retracted state, the first lens group 221, the third lens group 223, the fourth lens group 224, and the fifth lens group 225 move to a closer receiving position. When the zoom operation ring 203 is rotated to the wide-angle end in the retracted state, the first lens group 221, the third lens group 223, the fourth lens group 224, and the fifth lens group 225 extend towards the front side (subject side) and move to the predetermined usage position, while the shift lens 222 returns to the imaging position on the optical axis. Therefore, the lens barrel 201 is switched to... Figure 15 The state shown is when it is in use.

[0106] like Figure 15 and Figure 16 As shown, when the lens barrel 201 is in use (during digital camera 200 recording), the first lens group 221 to the sixth lens group 226 are positioned at predetermined positions on the optical axis. When the zoom operation ring 203 is set from the lens barrel 201 to the wide-angle end... Figure 15 When the lens barrel 201 rotates to the retracted state, the first lens group 221, the third lens group 223, the fourth lens group 224, and the fifth lens group 225 begin to retract towards the rear side. Simultaneously, the shift lens 222 retracts from the optical axis. That is, when the lens barrel 201 changes from its active state to its retracted, inactive state, the shift lens 222 moves from its intended imaging position to a predetermined retraction position, which is a predetermined distance away from the optical axis in a direction perpendicular to the optical axis (radial). The shift lens 222 moves from the imaging position to the retraction position in a manner similar to the retraction of the third set of retaining members 3 (third lens group 2) in the first embodiment. When the first lens group 221 moves into the space created by the retraction of the shift lens 222 and is stored without interference, the lens barrel 201 reaches its maximum position. Figure 17 The state shown is the shortest in terms of total length.

[0107] Figure 18 This is an exploded perspective view of the image stabilization device 600, including the shift lens 222, as viewed from the front side. Figure 19 This is a front view of the image stabilization device 600 showing the shift lens 222 in the camera position. Figure 20 This is a front view of the image stabilization device 600 showing the shift lens 222 in the retracted position.

[0108] The image stabilization device 600 includes a shift lens 222, a lens frame 602, a base member 603, a shift member 604, a torsion spring 605, a retraction lever 606, three balls 607 (rolling members), and three springs 608. The lens frame 602 is a holding member that holds the shift lens 222. The lens frame 602 is rotatably supported by a bearing of the shift member 604 via a rotation shaft 603e, which is press-fitted to the base member 603 parallel to the optical axis. Furthermore, during image stabilization, the shift lens 222 and the lens frame 602 move integrally with the shift member 604 in a plane perpendicular to the optical axis.

[0109] The torsion spring 605 is a force-applying member that pushes outward onto the base member 603 and applies force to the lens frame 602 in the direction relative to the displacement member 604 as it moves from the retracted position to the imaging position. The displacement member 604 is provided with three ball receiving surfaces 604c that respectively contact three balls 607 (see...). Figure 21 The three spring hooks 604b hook onto one side of each of the three springs 608. In addition, a pair of magnets 609 are arranged on the displacement member 604 at 90-degree intervals along the circumferential direction in a plane perpendicular to the optical axis.

[0110] The base component 603 is provided with three spring hooks 603b that respectively hook onto the other end of the three springs 608. Through the force of the three springs 608, the ball 607 is clamped between the ball receiving surface 604c of the displacement component 604 and the ball receiving surface 603c of the base component 603 (see...). Figure 21 In the state between ), the three balls 607 can roll in a plane perpendicular to the optical axis.

[0111] A pair of coils 610 and a pair of magnets 609 are arranged in phase on the base member 603. When current is supplied to the pair of coils 610, a Lorentz force is generated between the magnetism of the coils 610 and the magnets 609. The generated Lorentz force causes the displacement member 604 to move relative to the base member 603 in a plane perpendicular to the optical axis.

[0112] It should be noted that because the outer periphery of the displacement member 604 can contact the inner periphery of the base member 603, the range of motion of the displacement member 604 in a plane perpendicular to the optical axis is limited. For example, the approach portion 603a of the base member 603 can be constructed (see...). Figure 18 and Figure 19 This allows some portions of the side of the base member 603 to be used to restrict the movement of the displacement member 604.

[0113] The retractable lever 606 is attached to the outer periphery of the base member 603 near a groove (not shown) formed in the cam cylinder 208. When the cam cylinder 208 rotates toward the retracted position, a portion of the retractable lever 606 engages with the groove in the cam cylinder 208 according to the linear motion of the cam cylinder 208 relative to the linear guide cylinder 207. Therefore, the retractable lever 606 rotates about the rotation axis 603e in a plane perpendicular to the optical axis according to the movement of the cam cylinder 208, and the end portion 606a of the retractable lever 606 pushes the lens frame 602. As a result, the lens frame 602 rotates against the spring force of the torsion spring 605, and the shift lens 222 moves to the retracted position.

[0114] Figure 21 This illustrates the relationship between the lens frame 602 and the base member 603 when the shift lens 222 is in the retracted position. Figure 20 The first cross-sectional view taken from line DD is shown. When the shift lens 222 is viewed in the retracted position along the optical axis, a portion of the shift lens 222 protrudes outward from the outer periphery of the base member 603. The lens frame 602 has a protrusion 602a that protrudes towards the base member 603. The approach portion 603a of the base member 603 (see...) Figure 18 and Figure 19 The lens frame 602 protrusion 602a approaches the lens frame 602 when the shift lens 222 is in the retracted position. In other words, when the shift lens 222 is in the retracted position, the lens frame 602 protrusion 602a and the base member 603 approaching part 603a are positioned close to each other.

[0115] Therefore, when an external force such as a falling impact is applied while the shift lens 222 is in the retracted position, the protrusion 602a near the lens centroid collides with the approach portion 603a and is subjected to external force. This reduces the external force acting on the ball 607 and the ball receiving surfaces 603c and 604c, lowering the risk of damage such as dents in the ball 607 and the ball receiving surfaces 603c and 604c. As a result, the degradation of the rolling performance of the ball 607 is reduced, and the degradation of image stability performance is also reduced.

[0116] Incidentally, although it has been described that the protrusion 602a provided in the lens frame 602 and the approach portion 603a provided in the base member 603 approach each other when the shift lens 222 is in the retracted position, they can also partially contact each other in the optical axis direction.

[0117] When a structure is adopted in which the protrusion 602a and the approach portion 603a are in contact, it is preferable that the approach portion 603a is formed to have an inclined surface, such as... Figure 21 As shown, it moves away from the optical axis on its outer circumference and becomes closer to the lens frame 602 in the optical direction. Therefore, when the lens frame 602 moves away from the optical axis... Figure 19 The camera position in the middle is oriented towards Figure 20 When the protrusion 602a moves to the retreat position, it can move smoothly by riding on the inclined surface of the approach portion 603a.

[0118] Figure 22 It is shown that the state is along the following path Figure 20 The second cross-sectional view taken from line DD shows that, as the protrusion 602a moves by riding on the approach portion 603a, the displacement member 604 holding the lens frame 602 is tilted at an angle θ relative to a plane perpendicular to the optical axis. It should be noted that... Figure 21 In the middle, the displacement member 604 is parallel to the plane that intersects perpendicularly with the optical axis.

[0119] exist Figure 22 When the shift lens 222 is in the retracted position, the protrusion 602a and the approach portion 603a are indeed subjected to external force (impact). Furthermore, at least one of the three balls 607 has a gap between the ball receiving surface 604c of the shift member 604 and the ball receiving surface 603c of the base member 603. Therefore, even if the lens frame 602 is impacted, the risk of damage such as dents in the balls 607 and the ball receiving surfaces 603c and 604c is reduced due to the impact on the protrusion 602a and the approach portion 603a. This effect is particularly noticeable in the balls 607 closest to the protrusion 602a and their ball receiving surfaces near the centroid of the shift lens 222 in the retracted position.

[0120] In the second embodiment, as described above, even when the image stabilizing device 600 is subjected to an external force such as an impact while the shift lens 222 is in the retracted position, the risk of damage such as dents in the ball bearing 607 and the ball bearing receiving surfaces 603c and 604c can be reduced. Therefore, the performance degradation of image stabilization during imaging operations can be reduced. Furthermore, in the second embodiment, damage to the ball bearing 607 and the ball bearing receiving surfaces 603c and 604c can be avoided simply by changing the shape of a portion of the components of the general image stabilizing device, and no new components are required. Therefore, the image stabilizing device 600 is kept from becoming too large, and the lens barrel 801 is also kept from becoming too large.

[0121] Next, a third embodiment will be described. In the third embodiment, an image stabilization device with a construction different from the image stabilization device 600 described in the second embodiment will be described. Figure 23 This is an exploded perspective view of the image stabilization device 700 according to the third embodiment, viewed from the front side. Figure 24 This is a front view of the image stabilization device 700 with the shift lens 222 in the camera position. Figure 25 This is a front view of the image stabilization device 700 with the shift lens 222 in the retracted position. Figure 26 It is along Figure 25 The image stabilization device 700 is shown in a cross-sectional view taken by line CC.

[0122] The image stabilization device 700 includes a shifting lens 222, a lens frame 602, a base member 703, a shifting member 704, a torsion spring 605, a retraction lever 606, three balls 707 (rolling members), and three springs 608. Since the shifting lens 222, lens frame 602, torsion spring 605, retraction lever 606, a pair of magnets 609, and a pair of coils 610 are the same components constituting the image stabilization device 600 according to the second embodiment, their description is omitted. Furthermore, spring hooks 703b and 704b correspond to spring hooks 603b and 604b of the image stabilization device 600, respectively.

[0123] The image stabilization device 700 differs from the image stabilization device 600 described in the second embodiment in that a rolling support member 720 is arranged near the retracted position of the shift lens 222. This will be the main focus of the explanation below.

[0124] When the shift lens 222 is in the retracted position, the centroidal balance among the three balls 707 is disrupted. Therefore, when subjected to an external force such as an impact, dents may form in the ball 707 closest to the retracted position of the shift lens 222 and in its ball receiving surfaces 703c and 704c. To address this issue, a rolling support member 720 is disposed near the retracted position of the shift lens 222. The rolling support member 720 is a ball (sphere) disposed between the support ball receiving surface 703f of the base member 703 and the support ball receiving surface 704f of the shift member 704.

[0125] The rolling support member 720 can be clamped between the support ball receiving surfaces 703f and 704f in a contact state. Alternatively, a small gap may exist between the rolling support member 720 and the support ball receiving surfaces 703f and 704f. That is, the distance between the support ball receiving surfaces 703f and 704f in the optical axis direction may be longer than the distance between the ball receiving surfaces 703c and 704c. This is because it is preferable that the plane is defined by the three balls 707 in the imaging state. When the shift lens 222 is viewed in the retracted position in the optical axis direction, a portion of the shift lens 222 is farther away from the optical axis than the rolling support member 720.

[0126] When the shift lens 222 is in the retracted position and subjected to an external force such as an impact, the rolling support member 720, as well as the ball receiving surfaces 703f and 704f, are subjected to the external force due to the configuration of the rolling support member 720. As a result, the external force acting on the balls 707 and the ball receiving surfaces 703c and 704c is reduced, which lowers the risk of damage such as dents in the balls 707 and the ball receiving surfaces 703c and 704c. Consequently, the degradation of the rolling performance of the balls 707 is reduced, and the degradation of image stabilization performance is also reduced.

[0127] It should be noted that the support ball receiving surface 703f can be formed from a different material than the base member 703 using known techniques such as embedding and bonding. The support ball receiving surface 704f can also be formed from a different material than the displacement member 704. In this case, when the support ball receiving surfaces 703f and 704f are formed from a high-hardness material (e.g., metal, ceramic, etc.) that is harder than the materials of the ball receiving surfaces 703c and 704c, the risk of damage to the ball 707 and the ball receiving surfaces 703c and 704c can be further reduced.

[0128] In the third embodiment, as described above, even when the image stabilizing device is subjected to an external force such as an impact while the shift lens 222 is in the retracted position, the risk of damage such as dents in the ball bearing 707 and the ball receiving surfaces 703c and 704c can be reduced, just as in the second embodiment.

[0129] Next, the fourth embodiment will be described. Figure 27 This is a block diagram illustrating the electrical and optical configurations of a digital camera 800 according to a fourth embodiment. The appearance of the digital camera 800 is similar to that of the digital camera 200 according to a second embodiment (see...). Figure 13A and Figure 13B The components are largely the same, so an illustration of their appearance is omitted. Furthermore, the digital camera 800 differs from the digital camera 200 in the second embodiment, which is equipped with a lens barrel 201, in that it has a lens barrel 801. Additionally, compared to the lens barrel 201 in the second embodiment, the lens barrel 801 features an image stabilization device 900 and an aperture unit 350. Furthermore, a shift lens 822a is used instead of the shift lens 222 in the second embodiment. Other components are identical to those in the lens barrel 201. Therefore, in the following description, components of the digital camera 800 that are substantially the same as those of the digital camera 200 are indicated by the same reference numerals, and their descriptions are omitted. The image stabilization device 900 and the aperture unit 350 will be described primarily.

[0130] Figures 28 to 30 It shows a YZ cross-sectional view of the digital camera 800 (a cross-sectional view perpendicular to the X-axis), and is shown by a cross-section including the optical axis. Figure 28 This shows the state where the lens barrel 801 is set to the wide-angle end on the short focal length side. Figure 29 This shows the telephoto end of the lens barrel 801 set to the telephoto side. Figure 30 This shows the retracted state where the entire length of the lens tube 801 is at its shortest.

[0131] like Figure 28 and Figure 29 As shown, when the digital camera 800 is in the video recording operation state, all lens groups 211, 822a, 223 to 226 are arranged on the optical axis that is perpendicular to the imaging surface of the image sensor 236. Then, when the zoom operation ring 103 moves from... Figure 28 When the rotation operation reaches the retracted end as shown, the first lens group 221, the third lens group 223, the fourth lens group 224, and the fifth lens group 225 begin to retract towards the rear side (camera body 210 side), while the shift lens 822a retracts from the optical axis. When the first lens group 221 moves into the space created by the retraction of the shift lens 822a and is stored without interference, the lens barrel 801 reaches its maximum position. Figure 30 The shortest possible overall length is shown. The key 209 connecting the zoom operation ring 103 to the cam cylinder 108 is shown in... Figure 28 In the second embodiment ( Figures 14 to 16 Key 209 is not shown in the diagram.

[0132] The image stabilization device 900 includes a shift lens 822a as an image stabilization element. The shift lens 822a serves as a second lens group. The image stabilization device 900 then reduces image jitter by shifting the shift lens 822a in a plane perpendicular to the optical axis. In the description of the fourth embodiment, the state in which the shift lens 822a is in the imaging position on the optical axis is described as "the image stabilization device is in the imaging state." Furthermore, the state in which the shift lens 822a is retracted from the optical axis to a retracted position is described as "the image stabilization device is in the non-imaging state."

[0133] The image stabilization device 900 includes a shift lens 822a, a lens frame 822f, a retraction substrate 822b, an image stabilization substrate 822c, multiple coils 822d, and multiple magnets 822e. By supplying current to the coils 822d, the shift lens 822e can move in any direction in a plane perpendicular to the optical axis by the Lorentz force generated between the coils 822d and the magnets 822e.

[0134] The image stabilization device 600 of the second embodiment is configured to move the shift lens 222 to a retracted position by rotating the lens frame 602 holding the shift lens 222 about an axis parallel to the optical axis (Z-axis). In contrast, the image stabilization device 900 is configured to move the shift lens 822a to a retracted position by rotating the lens frame 822f holding the shift lens 822a about an axis parallel to the X-axis. This will be explained in detail below.

[0135] Next, we will refer to Figures 31A to 35 This explains the transition between the image stabilization device 900 and the aperture unit 350 in the lens barrel 801 in the imaging and non-imaging states. Figures 31A to 34B It shows a cross-sectional view of the lens barrel 801 and a perspective view showing the image stabilization device 900 and the aperture unit 350 in stages when the lens barrel 801 changes from the imaging state to the non-imaging state. Figure 35 This is a timing diagram showing the positional changes of the first lens group 221, the second lens group (shifting lens) 822a, and the aperture unit 350 when the lens barrel 801 changes from the imaging state to the non-imaging state.

[0136] Figure 31A This is a cross-sectional view of the lens barrel 801 when the image stabilization device 900 is in the imaging state. Figure 31B It is shown that... Figure 31A The image stabilization device 900 and aperture unit 350 are in a stereoscopic view corresponding to the state. Figure 31A and Figure 31B The state corresponds to Figure 35 The camera status during the time period between time points t0 and t1.

[0137] like Figure 31B As shown, the aperture unit 350 includes an aperture unit frame 351, an aperture driver 302, a drive ring 320, and a plurality of aperture blades 330. The aperture driver 302 is attached to the aperture unit frame 351, and the drive ring 320 and aperture blades 330 are movably supported by the aperture unit frame 351. When the aperture driver 302 is driven, the drive ring 320 is driven to drive the aperture blades 330 to form the desired aperture shape. As a result, the amount of light incident on the image sensor 236 is adjusted. A notch 351a is provided at the outermost periphery of the aperture unit frame 351 in such a way that a portion of the outermost periphery is removed.

[0138] When the image stabilization device 900 is in imaging mode, the shift lens 822a is positioned on the optical axis like the other lens groups. Furthermore, the aperture blades 330 are driven to any aperture size by the aperture driver 302 and the drive ring 320 in order to adjust the amount of light incident on the image sensor 236. Additionally, a light-shielding portion 320a, which is part of the drive ring 320, and a portion of the aperture blades 330 protrude from the notch 351a and block stray light. Figure 31B In the diagram, the portion of the aperture blade 330 that protrudes from the notch 351a is indicated by a dashed line because it is located on the +Z side of the light-shielding portion 320a.

[0139] Figure 32A This is a cross-sectional view showing the state of the zoom operation ring 103 rotating from the wide-angle end position toward the retracted end position. Figure 32A The first stage of the image stabilization device 900 transitioning from a camera state to a non-camera state is shown. Figure 32B It is shown that... Figure 32A The image stabilization device 900 and aperture unit 350 are in a stereoscopic view corresponding to the state. Figure 32A and Figure 32B Corresponding to Figure 35 The state at time point t2 in the data.

[0140] When the zoom ring 103 rotates from the wide-angle position toward the retracted position, the aperture unit 350, the third lens group 223, the focusing lens group 224, and the fifth lens group 225 move from the front position to the rear side due to the functions of the linear guide tube 107 and the cam tube 108. Therefore, the lens barrel 801 switches to a non-image-capturing state.

[0141] When the aperture unit 350 moves to the rear side, the drive ring 320 is mechanically rotated due to the functions of adjacent other groups or the straight-in guide tube 107 and cam tube 108, and the aperture blades 330 are driven to a smaller aperture state. At this time, the light-shielding part 320a of the drive ring 320 and a part of the aperture blades 330 protruding from the notch 351a are housed in the aperture unit frame 351.

[0142] When the zoom operation ring 103 moves from the first stage position ( Figure 32A and Figure 32B During the further rotation towards the retracted end, the first lens group 221 moves to the side of the shift lens 822a due to the function of the straight-in guide tube 107 and the cam tube 108. Since the third lens group 223 to the fifth lens group 225 move to the back side at this time, a space is created on the back side of the shift lens 822a. Therefore, the lens frame 822f of the image stabilization device 900 mechanically rotates around an axis parallel to the X-axis using this space. Thus, the shift lens 822a moves to a retracted position on the +Y direction side, away from the optical axis by a predetermined distance, and the image stabilization device 900 switches to a non-image-capturing state.

[0143] Figure 33A This is a cross-sectional view showing the zoom operation ring 103 rotating further from the first stage toward the retracted end position. Figure 33A The second stage of the image stabilization device 900's transition from a camera state to a non-camera state is shown. In this stage, the shift lens 822a moves to a retracted position, and the first lens group 221 moves to the space occupied by the shift lens 822a. Figure 33B It is shown that... Figure 33A The image stabilization device 900 and aperture unit 350 are in a stereoscopic view corresponding to the state. Figure 33A and Figure 33B The state corresponds to Figure 35 The state at time point t3.

[0144] When the zoom operation ring 103 moves from the second stage position ( Figure 33A and Figure 33B During further rotation toward the retracted end, the first lens group 221 and the image stabilization device 900, while maintaining their distance, move toward the rear side due to the function of the straight-in guide tube 107 and the cam tube 108. At this time, the aperture unit 350 has moved toward the rear side, and the light-shielding portion 320a of the drive ring 320 and a portion of the aperture blades 330 have been housed in the aperture unit frame 351. Therefore, a portion of the lens frame 822f (shifting lens 822a) is inserted into the notch 351a, and the image stabilization device 900 becomes closest to the aperture unit 350 in the optical axis direction.

[0145] It should be noted that the transition of the third lens group 223 to the non-image-taking state has already been completed on the back side of the aperture unit 350. Therefore, a portion of the shift lens 822a is housed in a manner that overlaps with the third lens group 223 in a plane perpendicular to the optical axis (when viewed from the +Y side, a portion of the shift lens 822a overlaps with the third lens group).

[0146] Figure 34A This is a cross-sectional view showing the state of the zoom operation ring 103 rotating further toward the retracted end from the second stage. Figure 34A This shows the state in which the image stabilization device 900 switches to a non-camera state. Figure 34B It is shown that... Figure 34A The image stabilization device 900 and aperture unit 350 are in a stereoscopic view corresponding to the state. Figure 34A and Figure 34B Corresponding to Figure 35 The state at time point t4.

[0147] Due to the switching operation of the lens barrel 801 from non-camera state to camera state (from... Figure 35 The time point t4 to time point t1 is the inverse operation from the camera state to the non-camera state, so its description is omitted.

[0148] As described above, in the fourth embodiment, since the aperture blades 330 are controlled as small holes in the non-image-capturing state, the amount of light incident on the image sensor 236 is reduced, thus preventing the image sensor 236 from burning out. Furthermore, in the non-image-capturing state, the shifting lens 822a constituting the image stabilization device 900 moves to a retracted position outside the optical axis, and a portion of the lens frame 822f is inserted into the notch 351a of the aperture unit frame 351. Therefore, the overall length of the lens barrel 108 in the retracted state can be shortened without increasing the outer diameter of the lens barrel 801.

[0149] In the fourth embodiment, by inserting a portion of the lens frame 822f of the image stabilizing device 900 adjacent to the aperture unit 350 into the notch 351a provided in the aperture unit 350, the overall length of the lens barrel 801 is shortened in the non-image-capturing state. However, as long as the overall length of the lens barrel 801 can be shortened, the component to be inserted into the notch 351a is not limited to the lens holder 822f that holds the image stabilizing device 822a. For example, an actuator (stepper motor, vibration actuator (ultrasonic motor), etc.) that serves as the drive source for the focusing lens group 224 or a guide rod that linearly guides the focusing lens group 224 can be inserted into the notch 351a. In addition, the operation of controlling the aperture blades 330 to a pinhole state in the non-image-capturing state is also applicable to a configuration where the lens frame 602 rotates around an axis parallel to the optical axis, as in the lens barrel 201 of the second embodiment. This reduces the risk of burn-out of the image sensor 236 of the camera body 210 to which the lens barrel 201 is attached.

[0150] Although the invention has been described in detail based on suitable embodiments, it is not limited to these specific embodiments, and various constructions without departing from the scope of the invention are also included. Furthermore, the above embodiments illustrate one implementation of the invention, and multiple embodiments can be suitably combined.

[0151] Although the optical device of the present invention is described as the lens barrel of a camera device, the optical device of the present invention is not limited thereto. For example, the present invention can be applied to observation devices such as binoculars, telescopes, and field lenses.

[0152] Other implementation methods

[0153] While the invention has been described with reference to exemplary embodiments, it should be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the appended claims should be accorded the broadest interpretation to cover all such variations, equivalent structures, and functions.

[0154] This application claims priority to Japanese Patent Application No. 2021-135594, filed on August 23, 2021, the entire contents of which are incorporated herein by reference.

Claims

1. An optical device, comprising: A lens assembly, which is arranged on the optical axis in a manner that allows it to move along the optical axis; A first axis is arranged parallel to the optical axis and has a first fixing part and a fitting part in a predetermined lens group fitted into the lens group; A support member that rotatably supports the first shaft by holding the first fixed portion, and The second axis is disposed parallel to the optical axis in the support member and has a second fixing part held by the support member and a contact part that contacts the predetermined lens group to adjust the position of the predetermined lens group in the direction of the optical axis. Its characteristic is that the central axis of the first fixing part is eccentric to the central axis of the fitting part. The first shaft is supported by the support member in a manner that allows it to rotate around the central axis of the first fixed part. The central axis of the second fixing part is eccentric to the central axis of the contact part, and the eccentricity of the second axis is greater than half the eccentricity of the first axis. The second shaft is supported by the support member in a manner that allows it to rotate about the central axis of the second fixed part, and The predetermined lens group can move between a camera position on the optical axis and a retracted position away from the optical axis by rotating about the first axis.

2. The optical device according to claim 1, wherein, When a straight line connecting the center of the first axis and the center of the second axis in a plane perpendicular to the optical axis is divided by a line passing through the center of the predetermined lens and perpendicular to the normal of the line, the length between the center of the first axis and the normal of the line is greater than the distance between the center of the second axis and the normal of the line.

3. The optical device according to claim 1, wherein, The first axis has a first adjustment section that is externally rotatable to move the center of the predetermined lens relative to the optical axis.

4. The optical device according to claim 3, wherein, The second axis has a second adjustment section, which is rotated from the outside to move the central axis of the predetermined lens relative to the optical axis.

5. The optical device according to claim 4, wherein, The second fixing part is disposed between the contact part and the second adjusting part.

6. The optical device according to claim 4 or 5, wherein, The first adjustment part and the second adjustment part are arranged in the same direction along the optical axis.

7. An image stabilization device, comprising: The optical device according to any one of claims 1 to 6; and A drive unit is configured to move the predetermined lens group in a plane perpendicular to the optical axis when the predetermined lens group is in an imaging position on the optical axis.

8. A microscope tube, comprising: The optical device according to any one of claims 1 to 6; and The lens group captures incident light and forms an image at a predetermined position on the optical axis.

9. A camera device, comprising: The optical device according to any one of claims 1 to 6; and Image sensor; The optical device captures incident light and forms an image on the image sensor.

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