Interchangeable lens and imaging device

Abstract

This interchangeable lens comprises: a fixed rod which has at least two magnets and at least one inner yoke and in which a magnetic body in which the magnet and the inner yoke are alternately connected is held by a cylindrical holding member; and a cylindrical movable coil into which the fixed rod is inserted and which is movable in the connection direction of the magnet and the inner yoke with respect to the fixed rod. The same poles of the magnets located on both sides are connected to the inner yoke, the outer peripheral surface of the magnetic body and the inner peripheral surface of the holding member are each formed in a shape having no corners, and the magnetic body is held in a state of being inserted in the holding member by being press-fitted thereto.

Description

Interchangeable lenses and imaging devices

[0001] The present technology relates to a technical field of an interchangeable lens and an imaging device that has a magnet and a moving coil and is operated by passing current through the moving coil.

[0002] There is a linear actuator that has a magnet and a moving coil, and when electricity is passed through the moving coil, a driving force is applied to a movable body to move it. Such linear actuators are used, for example, in interchangeable lenses and imaging devices (see, for example, Patent Documents 1 and 2).

[0003] In such interchangeable lenses and imaging devices, for example, a movable lens that functions as a zoom lens or a focus lens and a lens holder that holds the movable lens are provided as movable bodies, and zooming and focusing are performed by moving the movable lens together with the lens holder in the optical axis direction by the driving force of a linear actuator.

[0004] In the linear actuators described in Patent Documents 1 and 2, magnets and yokes (called "magnetic spacers" in Patent Document 2) are alternately connected to form a fixed rod, and the yoke is connected to magnets with the same poles located on both sides. In such linear actuators, when electricity is applied to the moving coil, a driving force is generated, and the movable lens moves in the optical axis direction together with the lens holder.

[0005] International Publication No. 2021 / 153017 Japanese Patent Application Laid-Open No. 2017-93222

[0006] However, in a configuration in which magnets of the same polarity are connected to both sides of a yoke, as in the linear actuators described in Patent Documents 1 and 2, while a high thrust can be obtained, a repulsive force is generated between the magnets on both sides, which can make the connection between the magnets and the yoke unstable and can make the assembly of the fixed rod difficult.

[0007] Therefore, an object of the interchangeable lens and imaging device of the present technology is to facilitate the assembly work of the fixed rod.

[0008] The interchangeable lens according to the present technology comprises a fixed rod in which a magnetic body having at least two magnets and at least one inner yoke and in which the magnets and the inner yoke are alternately connected is held by a cylindrical holding member, and a cylindrical movable coil through which the fixed rod is inserted and which is movable relative to the fixed rod in the direction in which the magnets and the inner yoke are connected, the same poles of the magnets positioned on both sides are connected to the inner yoke, the outer peripheral surface of the magnetic body and the inner peripheral surface of the holding member are each formed in a shape without corners, and the magnetic body is held in a state in which it is inserted into the holding member by being pressed in.

[0009] As a result, the magnetic body having no corners on its outer circumferential surface is inserted by press fitting into the cylindrical holding member having no corners on its inner circumferential surface.

[0010] The imaging device according to the present technology includes an imaging element that converts an optical image into an electrical signal, a fixed rod having at least two magnets and at least one inner yoke, and a magnetic body in which the magnets and the inner yoke are alternately connected, held by a cylindrical holding member, and a cylindrical movable coil through which the fixed rod is inserted and which can move relative to the fixed rod in the direction in which the magnets and the inner yoke are connected, and the same poles of the magnets positioned on both sides are connected to the inner yoke, and the outer surface of the magnetic body and the inner surface of the holding member are each formed in a shape without corners, and the magnetic body is held in a state in which it is inserted into the holding member by being pressed in.

[0011] As a result, the magnetic body having no corners on its outer circumferential surface is inserted by press fitting into the cylindrical holding member having no corners on its inner circumferential surface.

[0012] 17 shows an embodiment of an interchangeable lens and an imaging device according to the present technology, together with FIGS. 2 to 17 , and is a perspective view showing an interchangeable lens and an imaging device. FIG. 17 is a perspective view showing the internal structure of an interchangeable lens with a portion cut away. FIG. 18 is a cross-sectional view of the interchangeable lens as seen from the side. FIG. 19 is a cross-sectional view of the interchangeable lens as seen from the front. FIG. 19 is a perspective view of a linear actuator. FIG. 19 is a cross-sectional view of a linear actuator. FIG. 19 shows examples of the shape of the magnetic body together with FIGS. 8 to 11 , and is a view showing an example where the magnetic body is formed in an oval shape. FIG. 19 is a view showing an example where the magnetic body is formed in an elliptical shape. FIG. 19 is a view showing an example where the magnetic body is formed in a circular shape. FIG. 19 is a view showing an example where the outer periphery is surrounded by straight lines and curved lines. FIG. 19 is a view showing an example where the outer periphery is surrounded by curved lines only. FIG. 20 is a view showing the sizes of the magnetic body and a holding member. FIG. 21 is a conceptual diagram showing the presence area of ​​a fixed rod, etc. FIG. 22 is a conceptual diagram showing the generation state of magnetic flux in a linear actuator. FIG. 23 is a conceptual diagram showing the state of magnetic flux generated from a magnet. FIG. 24 is a conceptual diagram showing the forces generated in a magnet and an inner yoke. FIG. 25 is a block diagram of an imaging device.

[0013] Hereinafter, embodiments of the present technology will be described with reference to the accompanying drawings.

[0014] The following embodiment shows an example in which a linear actuator is provided in an interchangeable lens that is detachably attached to an imaging device. However, the present technology is not limited to a configuration in which a linear actuator is provided in an interchangeable lens, and can also be applied to a configuration in which a linear actuator is provided in an imaging device.

[0015] In the following description, the front, back, up, down, left and right directions are indicated as directions seen from the photographer when capturing an image using an imaging device. Therefore, the subject side (object side) is the front, and the image plane side is the rear. Note that the front, back, up, down, left and right directions shown below are for convenience of explanation, and the implementation of the present technology is not limited to these directions.

[0016] Furthermore, the lens groups described below may be configured with one or more lenses, or may include one or more lenses and other optical elements such as a diaphragm or iris.

[0017] <Configuration of Imaging Apparatus> First, the configuration of an imaging apparatus 100 to which an interchangeable lens 1 is attached / detached will be described (see FIG. 1).

[0018] The imaging device 100 is configured with required components arranged inside and outside a housing 101. A variety of operation units 102 are arranged on, for example, the top and rear surfaces of the housing 101. The operation units 102 include, for example, a power button, a shutter button, a zoom knob, a mode switching knob, and the like.

[0019] A display (display unit) (not shown) is disposed on the rear surface of the housing 101 .

[0020] A circular opening 101a is formed in the front surface of the housing 101, and a mount section 103 for attaching the interchangeable lens 1 is provided around the opening 101a. The mount section 103 has an annular coupling ring 103a and, for example, three arc-shaped mount engaging sections 103b that protrude inward from the coupling ring 103a, and the mount engaging sections 103b are provided spaced apart in the circumferential direction.

[0021] An image pickup element 104 such as a charge coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS) is disposed inside the housing 101, and the image pickup element 104 is positioned behind the opening 101a.

[0022] An arc-shaped contact portion 105 is disposed at the lower end inside the mount portion 103 .

[0023] <Configuration of Interchangeable Lens> Next, the configuration of the interchangeable lens 1 will be described (see FIGS. 1 to 13).

[0024] The interchangeable lens 1 is detachably attached to the imaging device 100, and is configured by arranging the required components inside and outside an outer barrel 2 (see FIG. 1).

[0025] A plurality of adjustment rings 3 are rotatably supported in a row on the outer peripheral surface of the outer barrel 2. The adjustment rings 3 have functions such as focusing adjustment, zooming adjustment, and aperture light amount adjustment.

[0026] A plurality of lens groups 4 are arranged spaced apart in the optical axis direction (front-rear direction) inside the outer barrel 2. Each lens group 4 has at least one lens, and inside the outer barrel 2, a front lens 4a located at the forefront as part of each lens group 4 and other lenses located behind the front lens 4a are arranged.

[0027] A lens mount 5 is attached to the rear end of the outer barrel 2. The lens mount 5 has, for example, three engaging protrusions 5a that protrude outward and are spaced apart in the circumferential direction. A connecting terminal (not shown) is provided on the rear end surface of the lens mount 5.

[0028] The interchangeable lens 1 is attached to the imaging device 100 by connecting the lens mount 5 to the mount portion 103. The interchangeable lens 1 can be attached to the imaging device 100 by rotating the entire interchangeable lens 1 in one direction around the optical axis relative to the imaging device 100.

[0029] When the interchangeable lens 1 is attached to the imaging device 100, the connection terminal is connected to the contact portion 105 of the imaging device 100. Therefore, a state is established in which signals can be exchanged and power can be supplied between the interchangeable lens 1 and the imaging device 100.

[0030] The interchangeable lens 1 can be removed from the imaging device 100 by rotating the entire interchangeable lens 1 in the other direction around the optical axis relative to the imaging device 100 and pulling it away from the imaging device 100 .

[0031] A mechanism unit 6 is disposed inside the interchangeable lens 1 (see FIGS. 2 to 4). The mechanism unit 6 is configured such that the required components are disposed on or supported by an inner barrel 7. Note that in the interchangeable lens 1, the inner barrel 7 may be provided integrally with the outer barrel 2 as a part of the outer barrel 2.

[0032] The inner tube 7 is formed from a non-magnetic material such as a resin material or a magnetic material, and has a cylindrical main body portion 8 whose axial direction is the optical axis direction (front-to-back direction) and an inner flange portion 9 that protrudes inward from the rear end of the main body portion 8.

[0033] A first bearing protrusion 10 protruding inward is provided at the front end of the main body 8. A second bearing protrusion 11 protruding inward is provided at approximately the center of the main body 8 in the front-to-rear direction, and the second bearing protrusion 11 is positioned approximately 180 degrees opposite the first bearing protrusion 10 in the circumferential direction.

[0034] Each of the inner flanges 9 is provided with a holding protrusion 12. The holding protrusion 12 is formed in a shape that protrudes forward, and has an insertion recess 12a that opens forward.

[0035] Mounting holes (not shown) are formed on the inner flange portion 9 at positions opposite to the central axis. The mounting holes are formed at positions, for example, 90 degrees apart in the circumferential direction from the retaining protrusions 12. Note that the positions at which the mounting holes are formed do not have to be 90 degrees apart in the circumferential direction from the retaining protrusions 12.

[0036] A bearing 13 is attached to each of the first bearing projection 10 and the second bearing projection 11 of the main body 8, and a bearing 13 is also attached to each of the mounting holes of the inner flange 9.

[0037] Two guide shafts 14 are attached to the inner cylinder 7. One guide shaft 14 is attached to the inner cylinder 7 via a bearing 13 attached to the first bearing protrusion 10 and a bearing 13 attached to one of the mounting holes, and the other guide shaft 14 is attached to the inner cylinder 7 via a bearing 13 attached to the second bearing protrusion 11 and a bearing 13 attached to the other mounting hole.

[0038] A linear actuator 15 is disposed on the inner cylinder 7 on the opposite side of the central axis of the main body 8. The linear actuator 15 has a fixed rod 16 and a moving coil 17 (see FIGS. 5 and 6).

[0039] The fixed rod 16 has at least two magnets 19 , for example, three magnets 19 , at least one inner yoke 20 , for example, four inner yokes 20 , and one holding member 21 .

[0040] The magnets 19 and the inner yokes 20 are alternately connected in a straight line, and the magnets 19 and the inner yokes 20 form a magnetic body 22. The inner yokes 20 are located at both ends of the magnetic body 22 in the direction in which the magnets 19 and the inner yokes 20 are connected (hereinafter simply referred to as the "connection direction").

[0041] The magnets 19 are magnetized so that their north and south poles are connected in the direction of connection. In the case of adjacent magnets 19 separated by an inner yoke 20, the same poles are connected to the inner yoke 20 located between the adjacent magnets 19, so that the north poles face each other or the south poles face each other.

[0042] The magnetic body 22 has an outer peripheral surface 22a formed in a shape without corners, and a cross-sectional shape in a direction perpendicular to the joining direction (front-to-back direction) is formed, for example, in an oval shape (see FIG. 7). Note that the cross-sectional shape of the magnetic body 22 in a direction perpendicular to the joining direction is not limited to an oval shape, and may be formed, for example, in an elliptical shape (see FIG. 8) or a circular shape (see FIG. 9). Furthermore, as long as the outer peripheral surface 22a of the magnetic body 22 is formed in a shape without corners, the cross-sectional shape in a direction perpendicular to the joining direction may be formed in a shape surrounded by curves and straight lines, for example, a substantially rectangular shape (see FIG. 10), or a shape surrounded only by curves, for example, a substantially arc shape (see FIG. 11).

[0043] The magnet 19 is formed as chamfered portions 19a by chamfering the outer circumferential surfaces of both ends in the direction of coupling with the inner yoke 20. The chamfered portions 19a are formed by C-chamfering or R-chamfering.

[0044] The inner yoke 20 is formed as chamfered portions 20a by chamfering the outer circumferential surfaces of both ends in the direction of coupling with the magnet 19. The chamfered portions 20a are formed by C-chamfering or R-chamfering.

[0045] The holding member 21 is formed into a cylindrical shape from a non-magnetic metal material such as copper, brass, or aluminum, and is formed into the same shape as the outer shape of the magnetic body 22. The holding member 21 may be formed from a magnetic metal material or a resin material.

[0046] However, since the holding member 21 is made of a ductile metal material, its strength is high, and since it is made of a non-magnetic metal material, there is no loss of magnetic flux, so it is possible to make it thinner, which allows the fixed rod 16 to be made thinner and the interchangeable lens 1 to be made smaller.

[0047] The length of the inner periphery N of the holding member 21 is equal to or smaller than the length of the outer periphery G of the magnetic body 22 (see FIG. 12). The holding member 21 is thin, for example, about 70 μm. The length of the holding member 21 in the axial direction is slightly shorter than the length of the magnetic body 22 in the coupling direction.

[0048] The magnetic body 22 is inserted into and held by the holding member 21 by press-fitting (see FIGS. 5 and 6). The fixed rod 16 is formed by the magnetic body 22 being press-fitted into and held by the holding member 21.

[0049] Since the magnetic body 22 has a chamfered portion 20a formed at the end in the longitudinal direction, when the magnetic body 22 is pressed into the holding member 21, the chamfered portion 20a is guided to the inner edge of the holding member 21, making it easier for the magnetic body 22 to be inserted into the holding member 21, and the magnetic body 22 can be pressed into the holding member 21 easily and quickly.

[0050] The magnetic body 22 can be press-fitted into the holding member 21 while the adjacent magnets 19 and inner yoke 20 are attracted to each other by magnetic force, facilitating the assembly of the fixed rod 16. In particular, because the magnets 19 and inner yoke 20 are attracted to each other, there is no need to perform fixing work such as gluing the two together, improving workability.

[0051] In a state in which the magnetic body 22 is held by the holding member 21 and the fixed rod 16 is configured, of the inner yokes 20A and 20B positioned at both ends, the inner yoke 20A positioned at the front has a portion of its outer circumferential surface covered by the holding member 21, and the inner yoke 20B positioned at the rear has its entire outer circumferential surface covered by the holding member 21. Therefore, a portion of the inner yoke 20A protrudes forward from the holding member 21.

[0052] When the magnetic body 22 is inserted into the holding member 21, one end of the holding member 21 is bent toward the inner yoke 20A and comes into close contact with the chamfered portion 20a. At this time, the bending of the holding member 21 toward the chamfered portion 20a is performed by, for example, pressing the end of the holding member 21 with a jig such as a roller. The portion of the holding member 21 that comes into close contact with the chamfered portion 20a is provided as a bent portion 21b.

[0053] In this way, the end of the holding member 21 is bent and tightly attached to the chamfered portion 20a, so that dust generated when the magnetic material 22 is pressed into the holding member 21 can be sealed between the magnetic material 22 and the holding member 21 by the bent portion 21b, thereby preventing dust from being dispersed into the interior of the interchangeable lens 1.

[0054] The moving coil 17 is formed in a cylindrical shape corresponding to the shape of the fixed rod 16 and has a two-phase configuration. The moving coil 17 is made up of, for example, a coil portion 17a constituting a first phase and a coil portion 17b constituting a second phase, with the coil portions 17a and 17b arranged side by side.

[0055] A fixed rod 16 is inserted through the moving coil 17 (see FIGS. 3 to 6 ). When a current is applied to the moving coil 17, a thrust is generated in the moving coil 17 in relation to the magnetic flux generated in the fixed rod 16, and the moving coil 17 is moved in the coupling direction of the fixed rod 16 (the optical axis direction) according to the direction of current flow through the moving coil 17.

[0056] In the linear actuator 15 configured as described above, one end (rear end) in the longitudinal direction of the fixed rod 16 is attached to the inner cylinder 7 (see FIG. 3). The fixed rod 16 is attached to the inner cylinder 7 by inserting a part of the inner yoke 20B and a part of the magnetic material 22 into the insertion recess 12a of the holding protrusion 12 and then by, for example, gluing, screwing, or press-fitting into the holding protrusion 12. Note that the interchangeable lens 1 may also be configured such that a positioning pin is provided on the holding protrusion 12, a positioning hole is formed in the inner yoke 20B, and the positioning pin is inserted into the positioning hole to position the fixed rod 16 on the holding protrusion 12.

[0057] As described above, when the fixed rod 16 is inserted into the insertion recess 12a, the bent portion 21b of the holding member 21 is guided by the opening edge of the insertion recess 12a, allowing the fixed rod 16 to be smoothly inserted into the insertion recess 12a. Furthermore, since the holding member 21 has the bent portion 21b, the sliding area between the holding protrusion 12 and the holding member 21 is reduced when the fixed rod 16 is inserted into the insertion recess 12a, thereby suppressing the generation of dust due to sliding.

[0058] The other end (front end) of the fixed rod 16 in the longitudinal direction is attached to and held by a holding base 23. The holding base 23 is made of a resin or metal material, and has a holding recess 24 that opens to the rear.

[0059] The fixed rod 16 is held by inserting the portion of the inner yoke 20A that protrudes forward from the holding member 21 into the holding recess 24. The inner yoke 20A is, for example, glued, screwed, or press-fitted into the holding base 23. Note that the interchangeable lens 1 may be configured such that a positioning pin is provided on the holding base 23, a positioning hole is formed in the inner yoke 20A, and the positioning pin is inserted into the positioning hole to position the fixed rod 16 on the holding base 23.

[0060] As described above, when fixed rod 16 is inserted into holding recess 24, chamfered portion 20a of inner yoke 20A is guided by the opening edge of holding recess 24, allowing fixed rod 16 to be smoothly inserted into holding recess 24. Furthermore, because inner yoke 20A has chamfered portion 20a, the sliding area between holding base 23 and inner yoke 20A is reduced when fixed rod 16 is inserted into holding recess 24, making it possible to suppress the generation of dust due to sliding.

[0061] At one end of the fixed rod 16, a portion of the inner yoke 20A protrudes forward from the holding member 21, preventing the holding member 21 from being inserted into the holding recess 24. Meanwhile, the magnetic body 22 is configured by combining a plurality of magnets 19 and a plurality of inner yokes 20, and there is a possibility that an error will occur in the length in the combined direction due to dimensional tolerances of the magnets 19 and the inner yokes 20. Therefore, by making the length of the holding member 21 shorter than the length of the magnetic body so that the holding member 21 cannot be inserted into the holding recess 24, even if an error occurs due to dimensional tolerances, the holding member 21 will not come into contact with the holding base 23, and this will prevent any problems with the attachment of the fixed rod 16 to the holding base 23.

[0062] The holding base 23 holding the fixed rod 16 is fixed to the inner peripheral surface of the inner cylinder 7 by screws or the like, and the fixed rod 16 is attached to the inner cylinder 7 via the holding base 23. The fixed rod 16 is attached to the inner cylinder 7 via the holding base 23 with the moving coil 17 inserted therethrough.

[0063] A lens holder 25 and the lens 4b are supported on the guide shaft 14 as movable bodies so as to be movable in the optical axis direction (see FIGS. 2 to 4). The lens 4b is one of the lens group 4, and is held by the lens holder 25. The lens 4b functions as, for example, a focus lens or a zoom lens.

[0064] The lens holder 25 has a frame-shaped lens holding portion 26, two supported portions 27 protruding in opposite directions on the outer periphery side from the lens holding portion 26, a pair of coil mounting portions 28 protruding in opposite directions on the outer periphery side from the lens holding portion 26, and a pair of mounting protrusions 29 each protruding in a predetermined direction on the outer periphery side from the lens holding portion 26. The supported portions 27 and the coil mounting portions 28 protrude from the lens holding portion 26 in directions perpendicular to each other.

[0065] The lens 4b is held by the lens holding portion 26. The lens 4b is attached to the lens holding portion 26 by adhesive, press-fitting, or the like.

[0066] The supported portions 27 are slidably supported on the guide shafts 14. Therefore, the lens holder 25 and the lens 4b are guided together by the guide shafts 14 and moved in the optical axis direction.

[0067] The coil portions 17a and 17b of the moving coil 17 are attached to the coil attachment portion 28 by adhesive or the like (see FIG. 3). Therefore, when a current is applied to the moving coil 17, the moving coil 17 moves in the optical axis direction relative to the fixed rod 16, and the lens holder 25 and the lens 4b move in the optical axis direction along with the moving coil 17.

[0068] By moving the lens 4b in the optical axis direction, for example, focusing or zooming is performed.

[0069] A detection bar 30 extending in the optical axis direction is attached to the mounting protrusion 29 (see FIGS. 2 and 4). The detection bar 30 moves in the optical axis direction together with the lens holder 25.

[0070] A detector 31 is attached to the inner peripheral surface of the main body 8 of the inner cylinder 7 at a position facing the detection bar 30. The detector 31 detects the position of the detection bar 30 when the lens holder 25 moves, and by detecting the position of the detection bar 30, the position of the lens 4b in the optical axis direction or the amount of movement in the optical axis direction is detected.

[0071] In the interchangeable lens 1 configured as described above, the two linear actuators 15 are positioned around the lens holder 25, and the area in which the fixed rod 16 exists is a region Ra that is part of the annular region R around the lens holder 25 (see Figure 13).

[0072] Therefore, it is desirable that the fixed rod 16 be formed into a shape that corresponds to the region Ra in order to increase the thrust by making the linear actuator 15 as large as possible without increasing the size of the interchangeable lens 1. As such a shape for the fixed rod 16, for example, an oval shape (see FIG. 7), a roughly sector shape (see FIG. 11), or an elliptical shape (see FIG. 8) are desirable.

[0073] In particular, by forming the fixed rod 16 into an oval shape, it is possible to increase the volumetric efficiency within the range of a shape that is easy to manufacture and has no corners, and it is possible to improve the thrust force without increasing the size of the interchangeable lens 1 while ensuring good manufacturability.

[0074] <Relationship Between Magnetic Flux and Moving Coil, etc.> Next, the relationship between the magnetic flux generated in the linear actuator 15 and the moving coil 17, etc. will be described (see FIGS. 14 to 16). Note that FIGS. 14 to 16 are shown as conceptual diagrams to easily explain the relationship between the magnetic flux generated in the linear actuator 15 and the moving coil 17, etc.

[0075] As described above, the fixed rod 16 of the linear actuator 15 is alternately connected to the magnets 19 and the inner yoke 20, and the magnets 19 are magnetized so that the north and south poles are aligned in the direction of connection, and adjacent magnets 19 are connected via the inner yoke 20 with the same poles, i.e., north and north poles or south and south poles, on both sides of the inner yoke 20 (see Figure 14).

[0076] FIG. 14 shows a state in which the center of the movable coil 17 in the axial direction coincides with the center in the coupling direction.

[0077] Magnetic flux J generated in magnet 19 passes from the north pole through inner yoke 20 connected to one surface of magnet 19, crosses holding member 21 and moving coil 17, and reaches the south pole through inner yoke 20 connected to the other surface of magnet 19. At this time, inner yoke 20 is connected to one end surface 19b of magnet 19 on the north pole side, and inner yoke 20 is connected to the other end surface 19c of magnet 19 on the south pole side, so that magnetic flux J flows from the north pole in the entire circumferential direction on the outer periphery of one end surface 19b, and then flows from the entire circumferential direction on the outer periphery of the other end surface 19c toward the south pole (see FIG. 15).

[0078] Therefore, since the magnetic flux J crosses the entire circumference of the moving coil 17, approximately 100% of the magnetic flux contributes to the thrust of the moving coil 17, and thrust is generated around the entire circumference of the moving coil 17, ensuring high driving efficiency in the linear actuator 15.

[0079] Furthermore, since thrust is generated around the entire circumference of the moving coil 17, high driving efficiency of the linear actuator 15 can be ensured. Therefore, even if each part of the linear actuator 15 is made smaller, sufficient driving force can be ensured, and the linear actuator 15 can be made smaller and lighter.

[0080] Furthermore, in the linear actuator 15, the same poles of adjacent magnets 19 are coupled to the inner yoke 20 (see FIG. 16). Therefore, a repulsive force P occurs between adjacent magnets 19, but in the linear actuator 15, the inner yoke 20 is disposed between the adjacent magnets 19, so an attractive force Q occurs between the inner yoke 20 and the magnets 19, reducing the repulsive force P occurring between the magnets 19.

[0081] Furthermore, since the inner yoke 20 is disposed between adjacent magnets 19, the adjacent magnets 19 are disposed with a certain distance therebetween, which also reduces the repulsive force P generated between the magnets 19.

[0082] Therefore, the difficulty of assembling the fixed rod 16 due to the generation of repulsive force P when the magnet 19 and the inner yoke 20 are joined is reduced, and the fixed rod 16 in which the same poles of adjacent magnets 19 are joined to the inner yoke 20 can be assembled easily and stably.

[0083] <Summary> As described above, in the interchangeable lens 1 and the imaging device 100, the magnetic body 22 comprises a fixed rod 16 held by a cylindrical holding member 21 and a cylindrical moving coil 17 that is movable relative to the fixed rod 16, the same poles of the magnets 19 positioned on both sides of the inner yoke 20 are connected, the outer surface 22a of the magnetic body 22 and the inner surface 21a of the holding member 21 are each formed in a shape that does not have corners, and the magnetic body 22 is held in a state where it is inserted into the holding member 21 by being pressed into it.

[0084] Therefore, since the magnetic body 22, which has no corners on its outer surface 22a, is inserted by press-fitting into the cylindrical holding member 21, which has no corners on its inner surface 21a, the magnetic body 22 is held in the holding member 21 by press-fitting, and the press-fitting operation can be carried out smoothly, making it easy to assemble the fixed rod 16.

[0085] Furthermore, since the inner surface 21a of the holding member 21 is smaller than the outer surface 22a of the magnetic body 22, the magnetic body 22 is inserted while the holding member 21 is pushed open, thereby ensuring a stable holding state of the holding member 21 against the magnetic body 22.

[0086] Furthermore, since the holding member 21 is formed from a non-magnetic metal material, the holding member 21 does not have any magnetic effect on the magnetic body 22, and since the holding member 21 has high strength, a high thrust force can be ensured and a stable holding state of the holding member 21 on the magnetic body 22 can be ensured.

[0087] <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. 17 ).

[0088] The imaging device 100 is equipped with a camera block 90 that performs imaging functions, and includes 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 includes 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 (102) such as various switches that are operated as required by the user.

[0089] The camera block 90 is, for example, an interchangeable lens 1 .

[0090] The imaging device 100 is provided with an imaging element 98 (104) such as a CCD or CMOS that converts the optical image captured by the camera block 90 into an electrical signal.

[0091] 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.

[0092] 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.

[0093] 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.

[0094] 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 .

[0095] 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.

[0096] The lens drive control unit 96 controls a drive source that moves the lens based on a control signal from the CPU 95 .

[0097] The operation unit 97 outputs to the CPU 95 an instruction input signal in response to an operation by the user.

[0098] 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 .

[0099] The operation of the imaging device 100 will be described below.

[0100] 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.

[0101] 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.

[0102] 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.

[0103] 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.

[0104] 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 a range of processes from the photoelectric conversion process of converting the light taken in by the imaging element 98 into an electrical signal to the processing of converting the output signal from the imaging element 98 by the camera signal processing unit 91 into a digital signal, noise removal, image quality correction, conversion into luminance and color difference signals, etc., or may refer to a range of processes from the photoelectric conversion process of converting the light taken in by the imaging element 98 into an electrical signal to the processing of converting the output signal from the imaging element 98 by the camera signal processing unit 91 into a digital signal, noise removal, image quality correction, conversion into luminance and color difference signals, etc., to the processing of It may also refer to processes such as the photoelectric conversion process of converting the light captured by the image sensor 98 into an electrical signal, the conversion of 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 compression coding / decompression decoding process of the image signal based on a predetermined image data format and conversion of data specifications such as resolution by the image processing unit 92, or the writing process of the image signal into the memory 99 by the R / W 94.

[0105] <Present Technology> The present technology can be configured as follows.

[0106] (1) An interchangeable lens comprising: a fixed rod having at least two magnets and at least one inner yoke, a magnetic body having the magnets and the inner yoke alternately connected, held by a cylindrical holding member; and a cylindrical movable coil through which the fixed rod is inserted and which is movable relative to the fixed rod in the direction in which the magnets and the inner yoke are connected, the same poles of the magnets located on both sides are connected to the inner yoke, the outer peripheral surface of the magnetic body and the inner peripheral surface of the holding member are each formed in a shape without corners, and the magnetic body is held in a state where it is inserted into the holding member by being pressed in.

[0107] (2) The interchangeable lens according to (1), wherein the length of the inner circumference of the holding member is smaller than the length of the outer circumference of the magnetic body.

[0108] (3) The interchangeable lens according to (1), wherein the holding member is formed from a non-magnetic metal material.

[0109] (4) The interchangeable lens according to any one of (1) to (3), wherein the fixed rod has an oval cross section perpendicular to the direction in which the magnet and the inner yoke are joined.

[0110] (5) The interchangeable lens according to (1), wherein the outer peripheral surface of the magnetic body is formed as a chamfered portion with at least one end in the direction in which the magnet and the inner yoke are joined being chamfered.

[0111] (6) The interchangeable lens according to (5), wherein the end of the holding member is in a bent state and is in close contact with the chamfered portion.

[0112] (7) An imaging device comprising: an imaging element that converts an optical image into an electrical signal; a fixed rod having at least two magnets and at least one inner yoke, a magnetic body having the magnets and the inner yoke alternately connected, held by a cylindrical holding member; and a cylindrical moving coil through which the fixed rod is inserted and which is movable relative to the fixed rod in the direction in which the magnets and the inner yoke are connected, wherein the same poles of the magnets located on both sides are connected to the inner yoke, the outer peripheral surface of the magnetic body and the inner peripheral surface of the holding member are formed into shapes without corners, and the magnetic body is held in a state where it is inserted into the holding member by being pressed into it.

[0113] REFERENCE SIGNS LIST 100 Imaging device 104 Imaging element 1 Interchangeable lens 16 Fixed rod 17 Moving coil 19 Magnet 20 Inner yoke 20a Chamfered portion 21 Holding member 21a Inner peripheral surface 22 Magnetic body 22a Outer peripheral surface 98 Imaging element

Claims

1. An interchangeable lens comprising: a fixed rod having a magnetic body, the magnetic body having at least two magnets and at least one inner yoke, the magnets and the inner yoke being alternately connected, held by a cylindrical holding member; and a cylindrical movable coil through which the fixed rod is inserted and which is movable relative to the fixed rod in the direction in which the magnets and the inner yoke are connected, the magnets positioned on both sides have the same poles connected to the inner yoke, the outer peripheral surface of the magnetic body and the inner peripheral surface of the holding member are formed in shapes without corners, and the magnetic body is held in a state where it is inserted into the holding member by being press-fitted.

2. The interchangeable lens according to claim 1, wherein the length of the inner circumference of the holding member is shorter than the length of the outer circumference of the magnetic body.

3. The interchangeable lens according to claim 1, wherein the holding member is made of a non-magnetic metal material.

4. The interchangeable lens according to claim 1, wherein the fixed rod has an oval cross section perpendicular to the direction in which the magnet and inner yoke are joined.

5. The interchangeable lens according to claim 1, wherein at least one end of the outer peripheral surface of the magnetic body in the direction of coupling between the magnet and the inner yoke is chamfered to form a chamfered portion.

6. The interchangeable lens according to claim 5, wherein the end of the holding member is bent and brought into close contact with the chamfered portion.

7. An imaging device comprising: an imaging element that converts an optical image into an electrical signal; a fixed rod having at least two magnets and at least one inner yoke, a magnetic body having the magnets and the inner yoke alternately connected, held by a cylindrical holding member; and a cylindrical moving coil through which the fixed rod is inserted and which is movable relative to the fixed rod in the direction in which the magnets and the inner yoke are connected, wherein the same poles of the magnets located on both sides are connected to the inner yoke, the outer peripheral surface of the magnetic body and the inner peripheral surface of the holding member are formed into shapes without corners, and the magnetic body is held in a state where it is inserted into the holding member by being press-fitted.

Images