Interchangeable lens and imaging device

Abstract

In this interchangeable lens, an actuator comprises: a coil attached to a movable body and having an axial direction in an optical axis direction; and a first drive magnet and a second drive magnet which are located on opposite sides in the optical axis direction with the coil interposed therebetween. The first drive magnet is located closer to a fixed body than the second drive magnet. A plurality of surface parts including a main surface part having the maximum area is provided on a magnetic plate. The main surface part is located in a state of facing the first drive magnet on the first drive magnet side of the center between the first drive magnet and the second drive magnet.

Description

Interchangeable lenses and imaging devices

[0001] The present technology relates to a technical field of an interchangeable lens and an imaging device having a configuration in which a movable body is movable relative to a fixed body in a direction perpendicular to the optical axis direction.

[0002] Some imaging devices such as video cameras and still cameras, as well as interchangeable lenses that are detachable from imaging devices, have a shake correction mechanism that corrects camera shake by moving the lens in a direction perpendicular to the optical axis direction, thereby improving image quality.

[0003] Among such interchangeable lenses and imaging devices, for example, there are some that have a blur correction mechanism in which a movable body having a lens is movable in a first direction perpendicular to the optical axis direction and a second direction perpendicular to both the optical axis direction and the first direction (see, for example, Patent Document 1).

[0004] The imaging device described in Patent Document 1 includes two actuators, each having a drive magnet, a coil, and a yoke, with the coil attached to a movable body and the drive magnet attached to a fixed body. The drive force of one actuator moves the movable body together with the coil of the actuator in a first direction, and the drive force of the other actuator moves the movable body together with the coil of the other actuator in a second direction.

[0005] The imaging device described in Patent Document 1 is configured such that a first drive magnet and a second drive magnet are disposed on opposite sides of a coil, thereby ensuring high drive efficiency of the image blur correction mechanism. Furthermore, a plurality of rollable spheres are disposed between a fixed body and a movable body, and the spheres roll relative to the fixed body and the movable body, thereby allowing the movable body to move in a direction perpendicular to the optical axis direction relative to the fixed body. A magnetic plate is attached to the movable body, and the magnetic plate is attracted to the drive magnet, thereby biasing the movable body in a direction approaching the fixed body, thereby maintaining the position and orientation of the movable body in the optical axis direction relative to the fixed body.

[0006] Japanese Patent Application Laid-Open No. 2020-101783

[0007] However, in a configuration in which a rolling sphere as described above is provided, if the first drive magnet and the second drive magnet are arranged on opposite sides of the coil, the magnetic plate will be attracted to both the first drive magnet and the second drive magnet, and the attractive force will fluctuate depending on the moving position of the movable body relative to the fixed body, which may result in the movable body not maintaining a stable posture relative to the fixed body.

[0008] Therefore, an object of the interchangeable lens and imaging device of the present technology is to suppress fluctuations in the attractive force of the drive magnet against the magnetic plate during shake correction, and to maintain a stable attitude of the movable body relative to the fixed body.

[0009] The interchangeable lens according to the present technology includes a fixed body fixed inside an outer tube, a movable body having a holding frame that holds a lens and that is moved relative to the fixed body in a first direction and a second direction that are respectively perpendicular to the optical axis direction, two actuators that impart moving forces to the movable body in the first direction and the second direction, a plurality of spheres that are made rollable between the fixed body and the movable body, and a magnetic plate that urges the movable body in a direction approaching the fixed body in the optical axis direction, the actuator having a coil attached to the movable body and whose axial direction is aligned with the optical axis direction, and a first drive magnet and a second drive magnet positioned on opposite sides of the coil in the optical axis direction, the first drive magnet being positioned closer to the fixed body than the second drive magnet, the magnetic plate having a plurality of surfaces including a main surface having a maximum area, the main surface being positioned facing the first drive magnet on the side of the first drive magnet from the center between the first drive magnet and the second drive magnet.

[0010] As a result, the main surface portion of the magnetic plate having the largest area is attracted to the first drive magnet, which is positioned closer to the fixed body than the second drive magnet.

[0011] an imaging device according to the present technology; a fixed body fixed inside a device body having an imaging element that converts a captured optical image into an electrical signal; a movable body having a holding frame that holds a lens and that is moved relative to the fixed body in a first direction and a second direction that are respectively perpendicular to the optical axis direction; two actuators that impart moving forces to the movable body in the first direction and the second direction, respectively; a plurality of spheres that are made rollable between the fixed body and the movable body; and a magnetic plate that urges the movable body in a direction approaching the fixed body in the optical axis direction, the actuator having a coil attached to the movable body and whose axial direction is aligned with the optical axis direction, and a first drive magnet and a second drive magnet positioned on opposite sides in the optical axis direction with the coil sandwiched between them, the first drive magnet being positioned closer to the fixed body than the second drive magnet, and the magnetic plate having a plurality of surfaces including a main surface portion with a maximum area, the main surface portion being positioned facing the first drive magnet on the first drive magnet side of the center between the first drive magnet and the second drive magnet.

[0012] As a result, the main surface portion of the magnetic plate having the largest area is attracted to the first drive magnet, which is positioned closer to the fixed body than the second drive magnet.

[0013] 2 to 11 show an interchangeable lens and an imaging device according to the present technology, and this figure is a perspective view of the imaging device. FIG. 1 is a perspective view of a shake correction mechanism. FIG. 2 is a perspective view showing the shake correction mechanism in a partially disassembled state. FIG. 3 is an exploded perspective view of the shake correction mechanism. FIG. 4 is a perspective view showing the movable body and the like as viewed from a direction different from that of FIG. 2. FIG. 5 is a cross-sectional view showing a first actuator and the like. FIG. 6 is a cross-sectional view showing a second actuator and the like. FIG. 7 is a perspective view of a magnetic plate. FIG. 8 is a perspective view of an actuator to which a magnetic plate according to a modified example is attached. FIG. 9 is a diagram showing measurement data. FIG. 10 is a block diagram of the imaging device.

[0014] Hereinafter, an embodiment of an interchangeable lens and an imaging device according to the present technology will be described with reference to the accompanying drawings.

[0015] In the embodiments of the present invention described below, the imaging device of the present technology is applied to a still camera, and the interchangeable lens of the present technology is applied to an interchangeable lens that is detachable from the still camera.

[0016] The application range of the imaging device and interchangeable lens of the present technology is not limited to still cameras and interchangeable lenses detachably attached to still cameras, respectively. The imaging device and interchangeable lens of the present technology can be widely applied to various imaging devices such as video cameras or interchangeable lenses detachably attached to these imaging devices.

[0017] In the following explanation, the front, back, up, down, left and right directions are indicated as viewed from the photographer when taking a picture with a still camera. Therefore, the subject side is the front and the photographer side is the rear. Therefore, the object side (subject side) is the front and the image plane side (photographer side) is the rear.

[0018] It should be noted that the directions of front, back, up, down, left and right shown below are for the convenience of explanation, and the implementation of the present technology is not limited to these directions.

[0019] Furthermore, the lens shown below includes both a lens configured from a single lens and a lens group configured from a plurality of lenses.

[0020] <Overall Configuration of Imaging Device> The imaging device 100 is configured with a device body 200, and an interchangeable lens 1 is detachably attached (see FIG. 1 ). However, the imaging device 100 may also be configured as a so-called retractable type in which the lens barrel is retractable.

[0021] The device main body 200 is configured by arranging the necessary parts inside and outside an outer casing 201 .

[0022] A plurality of various operation units 202 are arranged on, for example, the top and rear surfaces of the outer casing 201. The operation units 202 include, for example, a power button, a shutter button, a zoom knob, a mode switching knob, and the like.

[0023] A display (display unit) (not shown) is disposed on the rear surface of the outer casing 201. A circular opening (not shown) is formed on the front surface of the outer casing 201, and the area around the opening is provided as a mount for attaching the interchangeable lens 1. An image sensor (not shown), such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal-Oxide Semiconductor), is disposed inside the outer casing 201, and the image sensor is located behind the opening.

[0024] <Configuration of Interchangeable Lens> The interchangeable lens 1 is used for, for example, an interchangeable lens type digital camera.

[0025] The interchangeable lens 1 has an outer barrel 2, and at least one operation ring 3 for performing focusing and zooming is provided on the outer barrel 2. Manual focusing and manual zooming are performed by rotating the operation ring 3.

[0026] A lens mount (not shown) is provided at the rear end of the outer barrel 2 and is bayonet-coupled to a mount of the device body 200. A photographic lens 4 is attached to the front end of the outer barrel 2.

[0027] The configuration of the interchangeable lens 1 is not limited to the above configuration, and may be, for example, a type in which multiple outer barrels are provided and one outer barrel is extended or retracted relative to the other outer barrels to change the overall length.

[0028] Inside the interchangeable lens 1, multiple lenses (not shown) are positioned at a distance in the optical axis direction (front-to-back direction), and these lenses are composed of movable lenses (movable lens group) that can move in the optical axis direction and fixed lenses (fixed lens group) that cannot move in the optical axis direction.

[0029] A blur correction mechanism 5 that corrects camera shake is disposed inside interchangeable lens 1 (see FIGS. 2 to 5). Blur correction mechanism 5 has a fixed body 6 and a movable body 7. Blur correction mechanism 5 has the function of correcting camera shake by moving movable body 7 relative to fixed body 6 in a first direction and a second direction that are respectively perpendicular to the optical axis direction.

[0030] The fixed body 6 is disposed in a fixed state inside the outer cylinder 2. The fixed body 6 has a substantially circular outer shape and is made of a non-magnetic material such as a resin material. The fixed body 6 has a base surface portion 8 formed in a plate-like annular shape facing the front-to-rear direction, and a plurality of peripheral surface portions 9 protruding forward from a portion of the outer periphery of the base surface portion 8. The space inside the base surface portion 8 is formed as a light transmission hole 8a.

[0031] A plurality of positioning shafts 10 extending in the front-rear direction are provided at positions near the outer periphery of the base surface portion 8, spaced apart in the circumferential direction. The positioning shafts 10 are provided as insertion portions 10a whose diameters at the front and rear ends are smaller than the diameters of the other portions.

[0032] For example, three disk-shaped receiving plates 11 are attached to the base surface portion 8 at equal intervals in the circumferential direction. The front surfaces of the receiving plates 11 are exposed forward. A biasing metal plate 12 is attached to the base surface portion 8 at a position between the two receiving plates 11.

[0033] A plurality of cylindrical mounting bosses 9a are provided at the front end of the peripheral surface portion 9 and spaced apart in the circumferential direction.

[0034] The movable body 7 is supported by the fixed body 6 so as to be movable in a first direction (up and down) and a second direction (left and right) that are orthogonal to the optical axis direction, and has a holding frame 13 and a lens 14 .

[0035] The holding frame 13 is formed of a non-magnetic material such as a resin material, and has a substantially annular holding portion 15, and a first connecting protrusion 16, a second connecting protrusion 17, and an overhanging protrusion 18 that protrude from the holding portion 15. The holding portion 15 holds a lens 14, and the thickness direction of the lens 14 is aligned with the optical axis direction (front-to-back direction).

[0036] The first connecting protrusion 16 protrudes downward from the holding portion 15 and is formed in a horizontally elongated shape, while the second connecting protrusion 17 protrudes laterally from the holding portion 15 and is formed in a vertically elongated shape. The protruding protrusion 18 protrudes from the holding portion 15 in a range from above to the other side.

[0037] The first coupling protrusion 16 is formed in a horizontally long frame shape, and the inner space thereof is formed as a through-hole 16a. The second coupling protrusion 17 is formed in a vertically long frame shape, and the inner space thereof is formed as a through-hole 17a.

[0038] The lower end of the first connecting protrusion 16 is provided as a first mounting portion 19 extending laterally (see FIG. 6). The first mounting portion 19 is formed with recesses 19a that are open forward and spaced apart on the left and right.

[0039] The outer end of the second connecting protrusion 17 is provided as a second mounting portion 20 extending vertically (see FIG. 7). The second mounting portion 20 has two recesses 20a that are open forward and spaced apart vertically, with the portion between the recesses 20a coinciding with the vertical center of the second mounting portion 20.

[0040] An attraction magnet 21 is attached to the rear surface of the protruding portion 18 at the center in the circumferential direction (see FIG. 5).

[0041] For example, three pressing plates 22 are attached to the rear side of the holding portion 15. The pressing plates 22 are formed, for example, in a disk shape, and the rear surfaces thereof are exposed rearward.

[0042] A magnetic plate 23 made of a metal material is attached to the first mounting portion 19 of the first connecting protrusion 16 (see FIGS. 6 and 8). The magnetic plate 23 is integrally molded with the first connecting protrusion 16 by insert molding, for example. However, the magnetic plate 23 may also be attached to the first mounting portion 19 by adhesive or the like.

[0043] The magnetic plate 23 is formed by bending a plate-like material into a predetermined shape, and comprises a main surface portion 24 formed in a rectangular shape facing the front-to-rear direction, a pair of connecting surface portions 25 protruding in the same direction from both ends of the main surface portion 24, and a pair of overhanging surface portions 26 protruding in directions separating from each other from the tip ends of the connecting surface portion 25. The connecting surface portions 25 are bent at right angles to the main surface portion 24, and the overhanging surface portions 26 are bent at right angles to the connecting surface portion 25. The area of ​​the main surface portion 24 of the magnetic plate 23 is larger than the area of ​​the overhanging surface portions 26, making the main surface portion 24 the largest area. The rear surface of the main surface portion 24 is formed as an opposing surface 24a.

[0044] The magnetic plate 23 is attached to the first mounting portion 19 with the longitudinal direction of the main surface portion 24 oriented in the left-right direction. The pair of protruding surface portions 26 of the magnetic plate 23 are each positioned in a recess 19a formed in the first mounting portion 19, and one surface in the thickness direction of the pair of protruding surface portions 26 is formed as a mounting surface 26a, which is in surface contact with each portion of the first mounting portion 19.

[0045] A magnetic plate 23 is also attached to the second mounting portion 20 of the second connecting protrusion 17 (see FIGS. 7 and 8). The magnetic plate 23 is integrally molded with the second connecting protrusion 17 by insert molding, for example. However, the magnetic plate 23 may also be attached to the second mounting portion 20 by adhesive or the like.

[0046] The magnetic plate 23 is attached to the second mounting portion 20 with the longitudinal direction of the main surface portion 24 oriented in the up-down direction. The pair of protruding surface portions 26 of the magnetic plate 23 are each positioned in a recess 20a formed in the second mounting portion 20, and one surface in the thickness direction of the pair of protruding surface portions 26 is in surface contact with each portion of the second mounting portion 20.

[0047] The movable body 7 is supported on the fixed body 6 via a correction drive system 27, which is also called a compensator and corrects focus movement. The correction drive system 27 is composed of a support arm 28, a first shaft member 29, and a second shaft member 30.

[0048] The support arm 28 comprises a connecting portion 31 extending in a predetermined direction, for example, in a direction inclined at 45 degrees relative to both the up-down and left-right directions, and a pair of support portions 32 protruding in the same direction (rearward) perpendicular to both longitudinal ends of the connecting portion 31. An elongated shaft support hole 32a is formed at the tip of the support portion 32. The shaft support hole 32a is formed in a shape that is long in the direction in which the support portion 32 protrudes relative to the connecting portion 31.

[0049] The first shaft member 29 is passed through a pair of support portions 32, and both ends are fixed to the peripheral surface portion 9 of the fixed body 6. The support arm 28 is slidable relative to the first shaft member 29 in the axial direction of the first shaft member 29 and is rotatable around the first shaft member 29 as a fulcrum.

[0050] The second shaft member 30 is inserted into the shaft support holes 32a of the pair of support portions 32, and the portion between the shaft support holes 32a is fixed to the protruding portion 18 of the movable body 7. The second shaft member 30 is positioned parallel to the first shaft member 29, and is movable in the longitudinal direction of the shaft support hole 32a.

[0051] In the imaging device 100, the movable body 7 moves relative to the fixed body 6 in a first direction (up and down) and a second direction (left and right), each perpendicular to the optical axis direction. However, since the correction drive system 27 as described above is provided and the first shaft member 29 and the second shaft member 30 are always kept parallel, the movable body 7 does not rotate relative to the fixed body 6 in the roll direction within a plane perpendicular to the optical axis.

[0052] As described above, the movable body 7 is moved in the vertical and horizontal directions relative to the fixed body 6, with the vertical movement being performed by the driving force of the first actuator 33 and the horizontal movement being performed by the driving force of the second actuator 34.

[0053] The first actuator 33 has a part of a rear yoke 35, a part of a front yoke 36, a first drive magnet 37, a second drive magnet 38, and a coil 39 (see FIGS. 3 to 6).

[0054] The rear yoke 35 is formed in a plate shape facing the front-rear direction and is formed in a substantially arc shape. The rear yoke 35 has a first magnet mounting portion 35a and a second magnet mounting portion 35b, with the first magnet mounting portion 35a and the second magnet mounting portion 35b having larger areas than the other portions. The rear yoke 35 is disposed on the front side of the base surface portion 8 of the fixed body 6 with the rear insertion portion 10a of the positioning shaft 10 inserted from the front side.

[0055] The front yoke 36 is formed in a plate shape facing the front-rear direction and is formed in a generally arcuate shape. The front yoke 36 has a first magnet mounting portion 36a and a second magnet mounting portion 36b, with the first magnet mounting portion 36a and the second magnet mounting portion 36b having larger areas than the other portions. The front yoke 36 is attached to the mounting boss 9a of the peripheral surface portion 9 by screws or the like, with the front insertion portion 10a of the positioning shaft 10 inserted from the rear side. The first magnet mounting portion 36a is located in front of the first magnet mounting portion 35a, and the second magnet mounting portion 36b is located in front of the second magnet mounting portion 35b.

[0056] The rear yoke 35 and the front yoke 36 are positioned in the optical axis direction and held at a constant interval by inserting the insertion portions 10a of the positioning shafts 10 therethrough.

[0057] The first drive magnet 37 is configured, for example, by two rectangular parallelepiped magnets 37a. The first drive magnet 37 is attached to the front surface of the first magnet attachment portion 35a of the rear yoke 35 with the two magnets 37a oriented horizontally and lined up one above the other.

[0058] The second drive magnet 38 is composed of, for example, two rectangular parallelepiped magnets 38a. The second drive magnet 38 is attached to the rear surface of the first magnet attachment portion 36a of the front yoke 36 with the magnets 38a oriented horizontally and lined up one above the other.

[0059] The coil 39 is formed in a rectangular cylindrical shape with its axial direction extending in the front-to-rear direction. The coil 39 is composed of a pair of long portions 39a and a pair of short portions 39b. The coil 39 is attached to the front surface of the first coupling protrusion 16 with the pair of long portions 39a positioned vertically spaced apart and the pair of short portions 39b positioned horizontally spaced apart. When the coil 39 is attached to the first coupling protrusion 16, the magnetic plate 23 attached to the first mounting portion 19 is surrounded by the coil 39, and the coil 39 and the magnetic plate 23 are positioned between the first drive magnet 37 and the second drive magnet 38.

[0060] When the magnetic plate 23 is attached to the first mounting portion 19, the main surface portion 24, which has the largest area, is positioned closer to the first drive magnet 37 than the center M between the first drive magnet 37 and the second drive magnet 38, and the opposing surface 24a is positioned opposite the first drive magnet 37. Therefore, the magnetic plate 23 is exposed from the first coupling protrusion 16 to the first drive magnet 37 side.

[0061] The second actuator 34 has a part of the rear yoke 35, a part of the front yoke 36, a first drive magnet 37, a second drive magnet 38, and a coil 39, but each part is oriented differently from the first actuator 33 (see Figures 3, 4, 5, and 7).

[0062] In the second actuator 34, two magnets 37a are attached to the front surface of the second magnet mounting portion 35b of the rear yoke 35 in a vertically oriented, side-by-side relationship, and two magnets 38a are attached to the rear surface of the second magnet mounting portion 36b of the front yoke 36 in a vertically oriented, side-by-side relationship.

[0063] The coil 39 of the second actuator 34 is attached to the front surface of the second coupling protrusion 17 with its axial direction oriented in the front-rear direction, its pair of long portions 39a spaced apart from each other laterally, and its pair of short portions 39b spaced apart from each other vertically. When the coil 39 is attached to the second coupling protrusion 17, the magnetic plate 23 attached to the second mounting portion 20 is surrounded by the coil 39, and the coil 39 and the magnetic plate 23 are positioned between the first drive magnet 37 and the second drive magnet 38.

[0064] When the magnetic plate 23 is attached to the second mounting portion 20, the main surface portion 24, which has the largest area, is positioned closer to the first drive magnet 37 than the center M between the first drive magnet 37 and the second drive magnet 38, and the opposing surface 24a is positioned opposite the first drive magnet 37. Therefore, the main surface portion 24 of the magnetic plate 23 is exposed from the second coupling protrusion 17 to the first drive magnet 37 side.

[0065] In the interchangeable lens 1, various parts of a flexible printed circuit board (not shown) connected to a control circuit (not shown) are attached to the front surface of the holding frame 13 and the front surface of the coil 39, and a driving current is supplied to the coil 39 from the control circuit via the flexible printed circuit board.

[0066] The movable body 7 is positioned in the space on the inner surface side of the peripheral surface portion 9 in front of the base surface portion 8 of the fixed body 6, and is supported by the fixed body 6 via a correction drive system 27 (see FIG. 2). At this time, spheres 40 are respectively disposed between the receiving plate 11 attached to the fixed body 6 and the pressing plate 22 attached to the movable body 7. The spheres 40 roll against the receiving plate 11 and the pressing plate 22 when the movable body 7 is moved relative to the fixed body 6, and have the function of smoothly moving the movable body 7 relative to the fixed body 6 while maintaining the movable body 7 at a fixed distance from the base surface portion 8.

[0067] A position detection sensor (not shown) is mounted on the rear surface of each of the portions of the flexible printed circuit board attached to the two coils 39, and each position detection sensor is surrounded by the coil 39 and positioned facing the first drive magnet 37.

[0068] Therefore, when the movable body 7 is moved up and down relative to the fixed body 6, one of the position detection sensors detects a change in the magnetic flux generated in the first drive magnet 37 of the first actuator 33, and the vertical movement position of the movable body 7 is detected based on the detection result. The other position detection sensor detects a change in the magnetic flux generated in the first drive magnet 37 of the second actuator 34, and the horizontal movement position of the movable body 7 is detected based on the detection result.

[0069] In this way, in the interchangeable lens 1, the position of the movable body 7 is detected using the first drive magnet 37 of the first actuator 33 (second actuator 34), which improves detection accuracy and eliminates the need for a dedicated magnet for position detection, thereby reducing the number of parts in the interchangeable lens 1 and making it smaller.

[0070] When the movable body 7 is positioned in front of the base surface portion 8 and supported by the fixed body 6 via the correction drive system 27, the magnetic plates 23 attached to the first coupling protrusion 16 and the second coupling protrusion 17 are attracted to the first drive magnet 37, and the attracting magnets 21 attached to the holding frame 13 of the movable body 7 are attracted to the biasing metal plates 12 attached to the base surface portion 8 of the fixed body 6. Therefore, the movable body 7 is attracted toward the fixed body 6 by the magnetic force, the pressing plates 22 attached to the holding frame 13 are pressed against the spheres 40, and the spheres 40 are pressed against the receiving plates 11 of the fixed body 6, so that the spheres 40 roll smoothly against the pressing plates 22 and receiving plates 11 when the movable body 7 moves relative to the fixed body 6.

[0071] <Operation of Interchangeable Lens> In the interchangeable lens 1 configured as described above, when camera shake occurs during shooting or the like, the state of camera shake is detected by the camera shake detection unit, and the detection result is sent to the camera shake signal processing unit as an analog signal. The sent analog signal is converted by the camera shake signal processing unit into a digital signal indicating the magnitude and direction of the camera shake and sent to the control unit. The camera shake detection unit may be, for example, a gyro sensor.

[0072] Meanwhile, the position of the movable body 7 is detected by the position detection sensor described above, and the detection result is sent as an analog signal to the position detection signal processing unit. The sent analog signal is converted by the position detection signal processing unit into a digital signal indicating the position of the movable body 7 and sent to the control unit.

[0073] When the control unit receives digital signals from the hand shake signal processing unit and the position detection signal processing unit, feedback control is performed based on the two input digital signals, a drive current of a predetermined magnitude and a predetermined direction is supplied to either or both of the coil 39 of the first actuator 33 and the coil 39 of the second actuator 34, and the shake correction operation is performed by the shake correction mechanism 5.

[0074] When a drive current is supplied to the coil 39 of the first actuator 33, a vertical moving force is applied to the coil 39 in relation to the magnetic flux generated in the first drive magnet 37 and the second drive magnet 38, and the movement of the coil 39 causes the movable body 7 to move vertically relative to the fixed body 6. At this time, in the correction drive system 27, the support arm 28 moves in the axial direction of the first shaft member 29 relative to the first shaft member 29, and the second shaft member 30 moves relative to the shaft support hole 32 a of the support arm 28, causing the movable body 7 to move vertically without rotating in the roll direction.

[0075] When a drive current is supplied to the coil 39 of the second actuator 34, a moving force in the left-right direction is applied to the coil 39 in relation to the magnetic flux generated in the first drive magnet 37 and the second drive magnet 38, and as the coil 39 moves, the movable body 7 moves left-right relative to the fixed body 6. At this time, in the correction drive system 27, the support arm 28 moves in the axial direction of the first shaft member 29 relative to the first shaft member 29, and the second shaft member 30 moves relative to the shaft support hole 32 a of the support arm 28, so that the movable body 7 moves left-right without rotating in the roll direction.

[0076] In the interchangeable lens 1, the first drive magnet 37 and the second drive magnet 38 are positioned on opposite sides of the first actuator 33 and the second actuator 34, sandwiching the coil 39 therebetween, so that a large magnetic flux is generated in the first actuator 33 and the second actuator 34, a large driving force is applied to the movable body 7, and efficient shake correction operation is performed.

[0077] As described above, in the interchangeable lens 1, the position and orientation of the movable body 7 relative to the fixed body 6 are maintained by attraction of the magnetic plates 23 attached to the first coupling protrusion 16 and the second coupling protrusion 17, respectively, but the position of the magnetic plate 23 relative to the first drive magnet 37 and the second drive magnet 38 is changed by moving the movable body 7 through shake correction operation. Therefore, the magnetic forces of the first drive magnet 37 and the second drive magnet 38 relative to the magnetic plate 23 change as the movable body 7 moves.

[0078] However, as described above, the main surface portion 24 of the magnetic plate 23, which has the largest area, is positioned closer to the first drive magnet 37 than the center M between the first drive magnet 37 and the second drive magnet 38, and the opposing surface 24a is positioned opposite the first drive magnet 37. Therefore, even if the position of the magnetic plate 23 relative to the first drive magnet 37 and the second drive magnet 38 changes as the movable body 7 moves, the magnetic plate 23 is attracted to the first drive magnet 37 by a sufficient magnetic force regardless of the change in position. As a result, the pressing plates 22 attached to the holding frame 13 are reliably pressed against the spheres 40, and the spheres 40 are reliably pressed against the receiving plates 11 of the fixed body 6, ensuring a stable attitude of the movable body 7 relative to the fixed body 6 during shake correction operation, regardless of the movement position of the movable body 7 relative to the fixed body 6.

[0079] In particular, the main surface portion 24 of the magnetic plate 23 is formed in a shape that extends in the longitudinal direction of the long portion 39 a of the coil 39. In the interchangeable lens 1, the longitudinal direction of the long portion 39 a of the coil 39 of the first actuator 33 is the direction in which the movable body 7 is moved by the driving force of the second actuator 34, and the longitudinal direction of the long portion 39 a of the coil 39 of the second actuator 34 is the direction in which the movable body 7 is moved by the driving force of the first actuator 33. Therefore, when the movable body 7 is moved by the driving force of the second actuator 34, the attractive force of the first drive magnet 37 of the first actuator 33 on the magnetic plate 23 is less likely to change depending on the movement position of the movable body 7, and when the movable body 7 is moved by the driving force of the first actuator 33, the attractive force of the first drive magnet 37 of the second actuator 34 on the magnetic plate 23 is less likely to change depending on the movement position of the movable body 7. This allows the movable body 7 to be biased in a direction approaching the fixed body 6 in a more stable state regardless of the movement position of the movable body 7.

[0080] In addition, the magnetic plate 23 is provided with a pair of connecting surface portions 25 protruding in the same direction from both longitudinal ends of the main surface portion 24, and a pair of protruding surface portions 26 protruding in directions away from each other from the tip ends of the connecting surface portions 25, and the protruding surface portions 26 are attached to the first connecting protrusion 16 and the second connecting protrusion 17.

[0081] Therefore, the position of the main surface portion 24 relative to the first drive magnet 37 is determined by the amount of protrusion of the connecting surface portion 25 from the main surface portion 24, making it possible to easily set the position where the biasing force on the movable body 7 is generated to an appropriate position, thereby enabling the interchangeable lens 1 to be made smaller and the design freedom to be improved.

[0082] Furthermore, it is possible to position the main surface portion 24 closer to the first drive magnet 37, which allows the size of the main surface portion 24 to be reduced, and the weight of the interchangeable lens 1 to be reduced.

[0083] Furthermore, the surface of the protruding surface portion 26 facing the first drive magnet 37 is formed as the mounting surface 26a, and the magnetic plate 23 is attached to the first connecting protrusion 16 and the second connecting protrusion 17 with the mounting surface 26a in face contact with the first connecting protrusion 16 and the second connecting protrusion 17.

[0084] Therefore, the magnetic plate 23 is attached to the first and second coupling protrusions 16 and 17 with the attachment surface 26a facing the direction of attraction by the first drive magnet 37 in surface contact with the first and second coupling protrusions 16 and 17. As a result, when the magnetic plate 23 is attracted to the first drive magnet 37, the attachment surface 26a is pressed against the first and second coupling protrusions 16 and 17, preventing the magnetic plate 23 from falling off the first and second coupling protrusions 16 and 17, ensuring a stable attachment state of the magnetic plate 23 to the first and second coupling protrusions 16 and 17.

[0085] <Modified example of magnetic plate> The above shows an example of a magnetic plate 23 consisting of a main surface portion 24, a pair of connecting surface portions 25, and a pair of protruding surface portions 26, but in the interchangeable lens 1, a magnetic plate 23A may be used instead of the magnetic plate 23.

[0086] The magnetic plate 23A is provided with a pair of protruding surface portions 41 in addition to the main surface portion 24, the pair of connecting surface portions 25, and the pair of protruding surface portions 26. The pair of protruding surface portions 41 protrude from the main surface portion 24 to opposite sides, and the protruding direction is perpendicular to the extension direction of the main surface portion 24. The protruding surface portions 41 are, for example, located on the same plane as the main surface portion 24. By providing such protruding surface portions 41, the portion of the magnetic plate 23A where the main surface portion 24 and the pair of protruding surface portions 41 are joined is shaped to be longer.

[0087] By providing such a protruding surface portion 41, the shape of the magnetic plate 23A becomes longer in the first direction in which the movable body 7 is moved by the driving force of the first actuator 33 when the magnetic plate 23A is attached to the first connecting protrusion 16, and the shape of the magnetic plate 23A becomes longer in the second direction in which the movable body 7 is moved by the driving force of the second actuator 34 when the magnetic plate 23A is attached to the second connecting protrusion 17.

[0088] Therefore, the attractive force exerted by the first driving magnet 37 on the portion where the main surface portion 24 of the magnetic plate 23A and the pair of protruding surface portions 41 join together is less likely to change depending on the movement position of the movable body 7, and the movable body 7 can be urged in a stable manner in the direction approaching the fixed body 6 regardless of the movement position of the movable body 7.

[0089] <Measurement Data> Measurement data for the image blur correction mechanism 5 of the interchangeable lens 1 will be described below (see FIG. 10).

[0090] The horizontal axis in the measurement data represents the movement position of the movable body, with the reference position (the center position in the movement range) being shown as 0. The vertical axis in the measurement data represents the biasing force generated when the magnetic plate (magnetic plate 23, magnetic plate 23A, conventional magnetic plate) is attracted to the drive magnet. The movement direction of the movable body in the measurement data coincides with the direction perpendicular to the longitudinal direction of the main surface portion 24 of magnetic plate 23A.

[0091] The data shown by the dotted line is data when magnetic plate 23A was used, the data shown by the solid line is data when magnetic plate 23 was used, and the data shown by the dotted line is data when a conventional magnetic plate was used.

[0092] In a configuration in which the drive magnet and coil are positioned opposite each other in the optical axis direction, the conventional magnetic plate is disposed on the side of the coil opposite the drive magnet, so that the magnetic plate, coil, and drive magnet are arranged in this order in the optical axis direction.

[0093] As shown in Figure 10, it has been demonstrated that in a configuration using magnetic plate 23 and magnetic plate 23A, sufficient spring force is generated regardless of the movement position of movable body 7, and in particular, in a configuration using magnetic plate 23A, it has been demonstrated that the spring force generated is unlikely to change regardless of the movement position of movable body 7.

[0094] <Summary> As described above, in the interchangeable lens 1 and the imaging device 100, the first drive magnet 37 is positioned closer to the fixed body 6 than the second drive magnet 38, and the magnetic plates 23, 23A are provided with a plurality of surfaces including a main surface 24 with a maximum area, and the main surface 24 is positioned facing the first drive magnet 37 on the first drive magnet 37 side of the center between the first drive magnet 37 and the second drive magnet 38.

[0095] Therefore, the main surface portion 24, which has the largest area on the magnetic plates 23, 23A, is attracted to the first drive magnet 37, which is positioned closer to the fixed body 6 than the second drive magnet 38, so that fluctuations in the attractive force of the first drive magnet 37 and the second drive magnet 38 on the magnetic plates 23, 23A during shake correction can be suppressed, thereby maintaining a stable posture of the movable body 7 relative to the fixed body 6.

[0096] The holding frame 13 is provided with a holding portion 15 that holds the lens 14, and a first connecting protrusion 16 and a second connecting protrusion 17 that protrude from the holding portion 15 and to which a coil 39 is attached, and the coil 39 and magnetic plates 23, 23A are attached to the first connecting protrusion 16 and the second connecting protrusion 17.

[0097] Therefore, since both the coil 39 and the magnetic plates 23, 23A can be attached to the first connecting protrusion 16 and the second connecting protrusion 17 of the holding frame 13, no dedicated parts are required for attaching the magnetic plates 23, 23A, and the manufacturing costs of the interchangeable lens 1 and the imaging device 100 can be reduced by reducing the number of parts.

[0098] <One Embodiment of Imaging Apparatus> An example of the configuration of one embodiment of an imaging apparatus according to the present technology will be described below (see FIG. 11 ).

[0099] The imaging device 100 has a detachable camera block 90 that performs imaging functions. The imaging device 100 has a camera signal processing unit 91 that performs signal processing such as analog-to-digital conversion of captured image signals, and an image processing unit 92 that performs recording and playback processing of image signals. The imaging device 100 also has a display unit 93 that displays captured images, etc., an R / W (reader / writer) 94 that writes and reads image signals to and from a memory 99, a CPU (Central Processing Unit) 95 that controls the entire imaging device 100, a lens drive control unit 96 that controls the drive of a lens arranged in the camera block 90, and an operation unit 97 (202) such as various switches that are operated as required by the user.

[0100] The camera block 90 is, for example, an interchangeable lens 1 .

[0101] The imaging device 100 is provided with an imaging element 98 such as a CCD or CMOS that converts the optical image captured by the camera block 90 into an electrical signal.

[0102] The camera signal processing unit 91 performs various signal processing such as converting the output signal from the image sensor 98 into a digital signal, removing noise, correcting image quality, and converting into a luminance and color difference signal.

[0103] The image processing unit 92 performs processes such as compression encoding and decompression decoding of image signals based on a predetermined image data format, and conversion of data specifications such as resolution.

[0104] The display unit 93 has a function of displaying various data such as the operation status of the user on the operation unit 97 and the captured image, etc. Note that the imaging device 100 does not necessarily have to be provided with the display unit 93, and may be configured so that the captured image data is sent to another display device and the image is displayed thereon.

[0105] The R / W 94 writes image data encoded by the image processing unit 92 into a memory 99 and reads image data recorded in the memory 99 .

[0106] The CPU 95 functions as a control processing unit that controls each circuit block provided in the imaging device 100, and controls each circuit block based on instruction input signals from the operation unit 97, etc.

[0107] The lens drive control unit 96 controls a drive source that moves the lens based on a control signal from the CPU 95 .

[0108] The operation unit 97 outputs to the CPU 95 an instruction input signal in response to an operation by the user.

[0109] The memory 99 is, for example, a semiconductor memory that is detachable from a slot connected to the R / W 94 or a semiconductor memory that is pre-installed inside the imaging device 100 .

[0110] The operation of the imaging device 100 will be described below.

[0111] In a standby state for photographing, a photographed image signal is output to the display unit 93 via the camera signal processing unit 91 and displayed as a camera-through image under the control of the CPU 95. When an instruction input signal is input from the operation unit 97, the CPU 95 outputs a control signal to the lens drive control unit 96, and the lens is moved under the control of the lens drive control unit 96.

[0112] When a photographing operation is performed in response to an instruction input signal from the operation unit 97, the photographed image signal is output from the camera signal processing unit 91 to the image processing unit 92, where it is compressed and encoded and converted into digital data in a predetermined data format. The converted data is output to the R / W 94 and written to the memory 99.

[0113] When image data recorded in memory 99 is to be reproduced, the R / W 94 reads out the specified image data from memory 99 in response to an operation on the operation unit 97, and after the image processing unit 92 performs an expansion and decoding process, the reproduced image signal is output to the display unit 93 and the reproduced image is displayed.

[0114] In this technology, "imaging" refers to processing that includes only some or all of a series of processing, from photoelectric conversion processing that converts light captured by the imaging element 98 into an electrical signal, to processing by the camera signal processing unit 91 that converts the output signal from the imaging element 98 into a digital signal, noise removal, image quality correction, conversion into luminance and color difference signals, etc., to compression encoding / decompression decoding processing of the image signal based on a predetermined image data format and conversion processing of data specifications such as resolution, etc., by the image processing unit 92, and writing processing of the image signal to the memory 99 by the R / W 94.

[0115] That is, "imaging" may refer only to the photoelectric conversion process of converting the light taken in by the imaging element 98 into an electrical signal, or may refer to the process from the photoelectric conversion process of converting the light taken in by the imaging element 98 into an electrical signal to the process of converting the output signal from the imaging element 98 into a digital signal by the camera signal processing unit 91, noise removal, image quality correction, conversion into luminance and color difference signals, etc. ... to the process of converting the output signal from the imaging element 98 into an electrical signal by the image processing unit 91, noise removal, image quality correction, conversion into luminance and color difference signals, etc. 2 for compressing, encoding, and expanding / decoding the image signal based on a predetermined image data format and for converting data specifications such as resolution; or it may refer to the photoelectric conversion process for converting the light captured by the image sensor 98 into an electrical signal, to the processes for converting the output signal from the image sensor 98 into a digital signal, noise removal, image quality correction, conversion into luminance and color difference signals, etc., by the camera signal processing unit 91; and the compressing, encoding, and expanding / decoding process for the image signal based on a predetermined image data format and for converting data specifications such as resolution by the image processing unit 92; or it may refer to the process for writing the image signal to the memory 99 by the R / W 94.

[0116] In the above processes, the order of the processes may be changed as appropriate.

[0117] In addition, in the present technology, the camera block 90 and the imaging device 100 may be configured to include only some or all of the imaging element 98, camera signal processing unit 91, image processing unit 92, and R / W 94 that perform the above processing.

[0118] Furthermore, the camera block 90 may be configured to include some of the image pickup element 98 , the camera signal processing unit 91 , the image processing unit 92 , and the R / W 94 .

[0119] <Present Technology> The present technology can be configured as follows.

[0120] (1) An interchangeable lens comprising: a fixed body fixed inside an outer tube; a movable body having a holding frame for holding a lens and movable relative to the fixed body in a first direction and a second direction perpendicular to the optical axis direction; two actuators for imparting moving forces to the movable body in the first direction and the second direction, respectively; a plurality of spheres that are made rollable between the fixed body and the movable body; and a magnetic plate that urges the movable body in the optical axis direction toward the fixed body, wherein the actuator has a coil attached to the movable body with its axial direction aligned with the optical axis, and a first drive magnet and a second drive magnet positioned on opposite sides of the coil in the optical axis direction, the first drive magnet being positioned closer to the fixed body than the second drive magnet, and the magnetic plate having a plurality of surfaces including a main surface having a maximum area, and the main surface being positioned facing the first drive magnet on the first drive magnet side of the center between the first drive magnet and the second drive magnet.

[0121] (2) The interchangeable lens according to (1), wherein the coil is formed in a rectangular cylindrical shape and is composed of a pair of long sides and a pair of short sides, and the main surface portion is formed in a shape extending in the longitudinal direction of the long sides.

[0122] (3) The interchangeable lens according to (2), wherein the magnetic plate is provided with a protruding surface portion that protrudes from the main surface portion in a direction perpendicular to the longitudinal direction of the longitudinal portion.

[0123] (4) The interchangeable lens described in (2) or (3), wherein the holding frame is provided with a holding portion that holds the lens and a coupling protrusion that protrudes from the holding portion and to which the coil is attached, and the magnetic plate is provided with a pair of connecting surface portions that protrude in the same direction from both longitudinal ends of the main surface portion and a pair of protruding surface portions that protrude in directions away from each other from the tip ends of the connecting surface portions, and the protruding surface portions are attached to the connecting protrusions.

[0124] (5) The interchangeable lens according to (4), wherein the surface of the protruding surface portion facing the first drive magnet is formed as an attachment surface, and the magnetic plate is attached to the coupling protrusion with the attachment surface in surface contact with the coupling protrusion.

[0125] (6) The interchangeable lens according to (2) or (3), wherein the holding frame is provided with a holding portion that holds the lens and a coupling protrusion that protrudes from the holding portion and to which the coil is attached, and the coil and the magnetic plate are attached to the coupling protrusion.

[0126] (7) An imaging device comprising: a fixed body fixed inside a device body having an imaging element that converts a captured optical image into an electrical signal; a movable body having a holding frame that holds a lens and that is moved relative to the fixed body in a first direction and a second direction that are respectively perpendicular to the optical axis direction; two actuators that impart moving forces to the movable body in the first direction and the second direction, respectively; a plurality of spheres that are made rollable between the fixed body and the movable body; and a magnetic plate that urges the movable body in a direction approaching the fixed body in the optical axis direction, wherein the actuator has a coil attached to the movable body with its axial direction aligned with the optical axis, and a first drive magnet and a second drive magnet that are positioned on opposite sides of the coil in the optical axis direction, the first drive magnet being positioned closer to the fixed body than the second drive magnet, and the magnetic plate having a plurality of surfaces including a main surface having a maximum area, and the main surface being positioned facing the first drive magnet on the first drive magnet side of the center between the first drive magnet and the second drive magnet.

[0127] REFERENCE SIGNS LIST 100 Imaging device 1 Interchangeable lens 2 External barrel 6 Fixed body 7 Movable body 13 Holding frame 14 Lens 15 Holding portion 16 First coupling protrusion 17 Second coupling protrusion 23 Magnetic plate 24 Main surface portion 25 Connecting surface portion 26 Protruding surface portion 26a Mounting surface 33 First actuator 34 Second actuator 37 First drive magnet 38 Second drive magnet 39 Coil 39a Long portion 39b Short portion 40 Sphere 23A Magnetic plate 41 Protruding surface portion 98 Imaging element

Claims

1. An interchangeable lens comprising: a fixed body fixed inside an external tube; a movable body having a holding frame for holding a lens and movable in a first direction and a second direction perpendicular to the optical axis direction relative to the fixed body; two actuators for imparting moving forces in the first direction and the second direction to the movable body, respectively; a plurality of spheres allowed to roll between the fixed body and the movable body; and a magnetic plate for urging the movable body in the optical axis direction toward the fixed body, the actuator having a coil attached to the movable body with its axial direction aligned with the optical axis direction, and a first drive magnet and a second drive magnet positioned on opposite sides of the coil in the optical axis direction, the first drive magnet being positioned closer to the fixed body than the second drive magnet, the magnetic plate having a plurality of surfaces including a main surface having a maximum area, and the main surface being positioned facing the first drive magnet on the first drive magnet side of the center between the first drive magnet and the second drive magnet.

2. The interchangeable lens according to claim 1, wherein the coil is formed in a rectangular tube shape and is composed of a pair of long sides and a pair of short sides, and the main surface is formed in a shape extending in the longitudinal direction of the long sides.

3. The interchangeable lens according to claim 2, wherein the magnetic plate is provided with a protruding surface portion that protrudes from the main surface portion in a direction perpendicular to the longitudinal direction of the longitudinal portion.

4. An interchangeable lens as described in claim 2, wherein the holding frame is provided with a holding portion which holds the lens and a connecting protrusion which protrudes from the holding portion and to which the coil is attached, and the magnetic plate is provided with a pair of connecting surface portions which protrude in the same direction from both longitudinal ends of the main surface portion and a pair of protruding surface portions which protrude in directions separating them from each other from the tips of the connecting surface portions, and the protruding surface portions are attached to the connecting protrusions.

5. An interchangeable lens as described in claim 4, wherein the surface of the protruding surface portion facing the first drive magnet is formed as an attachment surface, and the magnetic plate is attached to the coupling protrusion with the attachment surface in surface contact with the coupling protrusion.

6. The interchangeable lens according to claim 1, wherein the holding frame is provided with a holding portion for holding the lens and a coupling protrusion protruding from the holding portion and to which the coil is attached, and the coil and the magnetic plate are attached to the coupling protrusion.

7. An imaging device comprising: a fixed body fixed inside a device body having an imaging element that converts a captured optical image into an electrical signal; a movable body having a holding frame that holds a lens and that is moved in a first direction and a second direction perpendicular to the optical axis direction relative to the fixed body; two actuators that impart moving forces in the first direction and the second direction to the movable body, respectively; a plurality of spheres that are allowed to roll between the fixed body and the movable body; and a magnetic plate that urges the movable body in a direction approaching the fixed body in the optical axis direction, wherein the actuator has a coil attached to the movable body and whose axial direction is aligned with the optical axis direction, and a first drive magnet and a second drive magnet that are positioned on opposite sides of the coil in the optical axis direction, wherein the first drive magnet is positioned closer to the fixed body than the second drive magnet, and the magnetic plate is provided with a plurality of surfaces including a main surface having a maximum area, and the main surface is positioned facing the first drive magnet on the first drive magnet side from the center between the first drive magnet and the second drive magnet.

Images