Lens barrel and imaging device

Abstract

The lens 8 has one surface of the outer periphery in the optical axis direction formed as a receiving surface 16 and the other surface formed as a pressed surface 17, a lens holding ring 4 having a lens receiving surface 9a that receives the received surface, an elastic member 18 pressed against the pressed surface, and a pressing ring 12 that is movable in the optical axis direction relative to the lens holding ring and has a pressing surface 14a that presses the elastic member from the optical axis direction, pressing the lens against the lens receiving surface via the elastic member.

Description

[Technical Field]

[0001] The present technology relates to a technical field of a lens barrel and an imaging device in which a lens is held by using a press ring and a lens holding ring. [Background technology]

[0002] Some imaging devices, such as video cameras and still cameras, are provided with a lens barrel that captures an optical image via a photographic optical system such as a lens, and the lens barrel is configured to have a plurality of lenses arranged in the optical axis direction. In some imaging devices, a lens barrel is not provided, and an interchangeable lens that is detachable from the imaging device is used as the lens barrel.

[0003] Some of such lens barrels are configured to hold the lens using a press ring and a lens holding ring (see, for example, Patent Documents 1, 2 and 3).

[0004] In the lens barrel described in Patent Document 1, the lens is held by being sandwiched in the optical axis direction between a pressing ring and a lens holding ring.

[0005] In the lens barrel described in Patent Document 2, the lens is clamped in the optical axis direction between a pressing ring and a lens holding ring, and round shaft-shaped resin is arranged circumferentially spaced apart between the outer surface of the lens and the inner surface of the lens holding ring, so that the lens is protected when an impact is applied in a direction perpendicular to the optical axis direction.

[0006] In the lens barrel described in Patent Document 3, the lens is clamped in the optical axis direction between a pressing ring and a lens holding ring, and an annular elastic member is arranged between the lens and the pressing ring, so that the lens is protected when an impact is applied in the optical axis direction. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-83723 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-215389 [Patent Document 3] Patent No. 6192560 Summary of the Invention [Problem to be solved by the invention]

[0008] However, in a lens barrel, when the lens is held by being clamped in the optical axis direction between a pressure ring and a lens retaining ring, the lens is in contact with both the pressure ring and the lens retaining ring in the optical axis direction, so impacts are easily transmitted to the lens without being attenuated by the pressure ring or lens retaining ring, which could cause the lens to become misaligned, damaged, or distorted, resulting in a deterioration in optical performance.

[0009] Therefore, an object of the lens barrel and imaging device of the present technology is to reduce the external load on the lens and ensure good optical performance. [Means for solving the problem]

[0010] A lens barrel according to the present technology includes a lens having an outer circumferential surface in an optical axis direction formed as a receiving surface and an outer circumferential surface formed as a pressed surface, a lens holding ring having a planar lens receiving surface extending in a circumferential direction that receives the receiving surface, an elastic member pressed against the pressed surface, and a pressing ring that is movable in the optical axis direction relative to the lens holding ring and has a pressing surface that presses the elastic member from the optical axis direction, and presses the lens against the lens receiving surface via the elastic member, and the lens holding ring has a lens facing surface positioned opposite the outer circumferential surface of the lens, a member receiving surface that faces in a direction different from the facing surface and receives the elastic member, the elastic member is pressed against the member receiving surface and the pressed surface, the lens is held by being clamped in the optical axis direction, the outer peripheral surface of the lens and the inner peripheral surface of the lens holding ring are kept out of contact, a plurality of screw holes are formed in the lens holding ring at intervals in the circumferential direction, adjustment screws that are made of an elastically deformable resin material and have tip surfaces that contact the outer peripheral surface of the lens are screwed into the screw holes, and the position of the lens in a direction perpendicular to the optical axis direction is adjusted depending on the screw position of the adjustment screw with respect to the screw hole Both surfaces of the elastic member in the optical axis direction are formed as flat surfaces facing the optical axis direction, the member receiving surface is formed in a direction facing the optical axis direction, the pressing surface is formed in a direction facing the optical axis direction, and one of the flat surfaces of the elastic member is pressed against the pressing surface and the other flat surface is pressed against the member receiving surface. It is something.

[0011] As a result, the elastic member is pressed by the pressing ring from the optical axis direction, and the elastic member is pressed against the pressed surface of the lens, and the received surface of the lens is received by the lens receiving surface of the lens holding ring, so that the pressing ring can hold the lens without contacting the lens. In addition, the outer peripheral surface of the lens is less likely to come into contact with the lens holding ring when an impact is applied.Furthermore, the position of the lens in a direction perpendicular to the optical axis direction is adjusted by a plurality of adjustment screws.

[0012] Secondly, in the lens barrel described above, it is desirable that the lens holding ring is formed with a member receiving surface that receives the elastic member, and the elastic member is pressed against the member receiving surface and the pressed surface.

[0013] As a result, the elastic member is pressed against a part of the pressing ring, a part of the lens, and a part of the lens holding ring in three directions.

[0014] Thirdly, in the above-described lens barrel, it is desirable that the elastic member be formed in an annular shape.

[0015] This makes it easier for the pressing force of the pressing ring to be applied uniformly to the outer periphery of the lens via the elastic member.

[0016] Fourth, in the above-described lens barrel, it is desirable that the pressed surface is formed with an inclined portion inclined with respect to the optical axis direction and a direction perpendicular to the optical axis direction, and that the elastic member be pressed against the inclined portion.

[0017] As a result, the lens is held in a state in which the elastic member is pressed against the inclined portion inclined with respect to the optical axis direction and a direction perpendicular to the optical axis direction.

[0020] above In the above-described lens barrel, it is desirable that the pressing ring is moved in the optical axis direction relative to the lens holding ring by rotating in the axial direction, that an annular first sheet is disposed between the pressing ring and the elastic member, and that the pressing ring is pressed against the elastic member via the first sheet.

[0021] This allows the pressing ring to slide against the first sheet when rotating around the axis.

[0022] above In the above-described lens barrel, it is desirable that both surfaces of the elastic member in the optical axis direction are formed as flat portions facing the optical axis direction, that a member receiving surface for receiving the elastic member is formed on the lens holding ring, that the member receiving surface is formed in a direction facing the optical axis direction, that the pressing surface is formed in a direction facing the optical axis direction, and that one flat portion of the elastic member is pressed against the pressing surface and the other flat portion is pressed against the member receiving surface.

[0023] This increases the contact area of ​​the elastic member with the lens holding ring and the pressing ring.

[0026] aboveIn the above-described lens barrel, it is desirable that the adjustment screw be made of an elastically deformable resin material.

[0027] This allows the plurality of adjustment screws to be elastically deformed when an impact is applied to the lens.

[0028] above In the above-described lens barrel, it is desirable that an annular second sheet be disposed between the lens receiving surface and the received surface, and that the lens be pressed against the lens receiving surface via the second sheet.

[0029] This allows the lens to slide onto the second seat when adjusted by the adjustment screw.

[0030] above In the above-described lens barrel, it is desirable that the linear expansion coefficient of the adjustment screw is made larger than that of the lens holding ring, and that the linear expansion coefficient of the lens holding ring is made larger than that of the lens.

[0031] As a result, when the environment in which the lens barrel is used changes, the expansion or contraction rate of the adjustment screw becomes greater than that of the lens retaining ring, and the expansion or contraction rate of the lens retaining ring becomes greater than that of the lens.

[0032] An imaging device according to the present technology includes a lens barrel that captures an optical image and an imaging element that converts the captured optical image into an electrical signal, the lens barrel including a lens having one surface of an outer periphery in an optical axis direction formed as a receiving surface and the other surface formed as a pressed surface, a lens holding ring having a planar lens receiving surface extending in a circumferential direction that receives the received surface, an elastic member that is pressed against the pressed surface, and a pressing ring that is movable in the optical axis direction relative to the lens holding ring and has a pressing surface that presses the elastic member from the optical axis direction, and presses the lens against the lens receiving surface via the elastic member, and the lens holding ring includes a lens having an outer periphery of the lens formed as a receiving surface and the other surface formed as a pressed surface, the lens holding ring having a planar lens receiving surface extending in a circumferential direction that receives the received surface, an elastic member that is pressed against the pressed surface, and a pressing ring that is movable in the optical axis direction relative to the lens holding ring and has a pressing surface that presses the elastic member from the optical axis direction, and presses the lens against the lens receiving surface via the elastic member, a lens-facing surface positioned opposite the surface to which the lens is pressed, and a member-receiving surface facing in a different direction from the lens-facing surface and receiving the elastic member; the elastic member is pressed against the member-receiving surface and the pressed surface, and the lens is held by being sandwiched in the optical axis direction, and the outer peripheral surface of the lens and the inner peripheral surface of the lens holding ring are kept out of contact; a plurality of screw holes are formed in the lens holding ring at intervals in the circumferential direction; adjustment screws formed from an elastically deformable resin material and having tip surfaces that contact the outer peripheral surface of the lens are screwed into the screw holes; and the position of the lens in a direction perpendicular to the optical axis direction is adjusted depending on the screw position of the adjustment screw with respect to the screw hole. Both surfaces of the elastic member in the optical axis direction are formed as flat surfaces facing the optical axis direction, the member receiving surface is formed in a direction facing the optical axis direction, the pressing surface is formed in a direction facing the optical axis direction, and one of the flat surfaces of the elastic member is pressed against the pressing surface and the other flat surface is pressed against the member receiving surface. It is something.

[0033] As a result, in the lens barrel, the elastic member is pressed by the pressing ring from the optical axis direction, and the elastic member is pressed against the pressed surface of the lens, and the received surface of the lens is received by the lens receiving surface of the lens holding ring, so that the pressing ring can hold the lens without contacting the lens. In addition, the outer peripheral surface of the lens is less likely to come into contact with the lens holding ring when an impact is applied.Furthermore, the position of the lens in a direction perpendicular to the optical axis direction is adjusted by a plurality of adjustment screws. [Brief explanation of the drawings]

[0034] [Figure 1] 2 to 7 show an embodiment of a lens barrel and an imaging device according to the present technology, and this figure is a perspective view of an imaging device in which the lens barrel and the device main body are separated. [Figure 2]FIG. 2 is an exploded perspective view showing a part of the lens barrel. [Figure 3] FIG. 2 is a cross-sectional view showing a part of a lens barrel. [Figure 4] FIG. 2 is an enlarged cross-sectional view showing a part of the lens barrel. [Figure 5] FIG. [Figure 6] FIG. 10 is an enlarged cross-sectional view showing an example in which another elastic member is used. [Figure 7] FIG. 1 is a block diagram of an imaging device. DETAILED DESCRIPTION OF THE INVENTION

[0035] Hereinafter, embodiments of the present technology will be described with reference to the accompanying drawings.

[0036] In the embodiment described below, the imaging device of the present technology is applied to a still camera, and the lens barrel of the present technology is applied to an interchangeable lens that is detachable from the device body of the still camera.

[0037] The application scope of this technology is not limited to still cameras and interchangeable lenses that can be attached to and detached from the main body of a still camera. For example, this technology can be widely applied to various imaging devices incorporated into video cameras and other devices as imaging devices, and lens barrels such as lens units composed of lens groups provided in these imaging devices.

[0038] In the following description, 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.

[0039] 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.

[0040] 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.

[0041] <Configuration of imaging device> Imaging device 100 is made up of device body 200 and lens barrel 1 (see FIG. 1). Lens barrel 1 is, for example, an interchangeable lens that can be attached to and detached from device body 200. Note that the present technology can also be applied to a type in which a lens unit having a structure similar to the internal structure of lens barrel 1 is incorporated inside the device body, or a retractable type in which this lens unit protrudes from or is retracted into the device body.

[0042] The device main body 200 is configured by arranging the required parts inside and outside an outer casing 201 .

[0043] Various operation units 202, 202, ... are arranged on, for example, the top surface or the back surface of the outer casing 201. The operation units 202, 202, ... include, for example, a power button, a shutter button, a zoom knob, a mode switching knob, and the like.

[0044] A display (display unit) not shown is disposed on the rear surface of the outer casing 201.

[0045] A circular opening 201a is formed in the front surface of the outer casing 201, and the area around the opening 201a is provided as a mount portion 203 for mounting the lens barrel 1.

[0046] An imaging element 204 such as a charge coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS) is disposed inside the outer casing 201, and the imaging element 204 is positioned behind the opening 201a.

[0047] <Lens barrel configuration> The lens barrel 1 consists of a roughly cylindrical outer barrel 2 whose axial direction is in the front-to-rear direction, and the necessary parts attached to or supported on the inside and outside of the outer barrel 2 (see Figures 1 and 2). The axial direction is aligned with the optical axis.

[0048] The outer tube 2 is configured, for example, by connecting a main body tube portion 3 and a lens holding ring 4 in the axial direction, and both the main body tube portion 3 and the lens holding ring 4 are formed, for example, from a metal material. The main body tube portion 3 has a base tube portion 5 except for its rear end portion, and the rear end portion is configured as a connecting tube portion 6 having an outer diameter slightly smaller than that of the base tube portion 5.

[0049] Mounting protrusions 6a, 6a, 6a are provided circumferentially spaced apart on the coupling tube portion 6. The lens barrel 1 is attached to the device body 200 by coupling the mounting protrusions 6a, 6a, 6a to the mount portion 203 by, for example, bayonet coupling.

[0050] The lens barrel 1 is provided with operation rings 7, 7 that function as a zoom ring and a focus ring. The operation rings 7, 7 are rotatably supported on the base cylinder portion 5, and zooming and focusing are performed by rotating the operation rings 7, 7.

[0051] The lens barrel 1 has, for example, a plurality of lenses (lens groups) 8, 8, ... (see Figs. 1 to 3). Note that Figs. 1 to 3 only show the frontmost lens 8A. The lenses 8, 8, ... are positioned at intervals in the optical axis direction (front-to-back direction), and include movable lenses (movable lens groups) that can move in the optical axis direction and fixed lenses (fixed lens groups) that cannot move in the optical axis direction.

[0052] The lens retaining ring 4 is formed in a substantially circular ring shape and is connected to the front end of the main body tubular portion 3. A flange-shaped receiving protrusion 9 that protrudes inward is provided at the middle portion of the lens retaining ring 4 in the front-to-rear direction (axial direction) (see FIG. 3). The front surface of the receiving protrusion 9 is formed as a lens receiving surface 9a that faces forward (see FIG. 4).

[0053] The front portion of the receiving protrusion 9 on the lens retaining ring 4 is provided as a hole forming portion 10, and screw holes 10a, 10a, ... that penetrate the lens retaining ring 4 in the radial direction are formed in the hole forming portion 10 at equal intervals in the circumferential direction. A filling recess 10b that opens outward and is continuous with the screw hole 10a is formed on the outer periphery of the hole forming portion 10 (see FIG. 5). The filling recess 10b is a recess that is filled with adhesive, and is formed continuous with the screw hole 10a in the circumferential direction of the lens retaining ring 4.

[0054] The inner peripheral surface of the hole forming section 10, excluding the front end, is formed as a lens-facing surface 10c parallel to the optical axis P (see FIG. 2), with the rear edge of the lens-facing surface 10c continuing to the outer peripheral edge of the lens receiving surface 9a (see FIG. 4). A member receiving surface 10d is formed in the hole forming section 10, continuing to the front edge of the lens-facing surface 10c. The member receiving surface 10d is inclined in a direction approaching the outer peripheral surface 10e of the hole forming section 10 as it moves forward from the lens-facing surface 10c. A sheet receiving surface 10f facing forward is formed on the inner peripheral side of the hole forming section 10, and the sheet receiving surface 10f is positioned forward of the member receiving surface 10d.

[0055] The front portion of the hole forming portion 10 in the lens holding ring 4 is provided as a connecting portion 11, and part of the inner circumferential surface of the connecting portion 11 is formed as a screw groove portion 11a in which a screw groove is formed.

[0056] A pressing ring 12 is connected to the connecting portion 11 of the lens holding ring 4 (see FIGS. 2 and 3). The pressing ring 12 is formed, for example, from a metal material in a substantially circular ring shape, and is formed in a shape in which the inner diameter decreases toward the rear.

[0057] A portion of the outer peripheral surface of the retaining ring 12 is formed as a threaded portion 12a with a screw groove. A plurality of diameter changing portions 12b, 12b, ... with different diameters are formed continuously on the inner peripheral surface of the retaining ring 12, each with a step therebetween, and the diameters of the diameter changing portions 12b, 12b, ... become smaller toward the rear. By configuring the inner peripheral surface of the retaining ring 12 to have a plurality of diameter changing portions 12b, 12b, ..., when external light enters the interior of the retaining ring 12, the incident external light is diffused, and the incidence of high-intensity light on the imaging element 204 is suppressed.

[0058] The front end of the pressing ring 12 is provided as a maximum diameter portion 13 that is positioned radially outward from the other portions. The rear end of the pressing ring 12 is provided as an action portion 14. Approximately half of the outer circumferential side of the rear surface of the action portion 14 is formed as a pressing surface 14a that faces rearward (see FIG. 4). Approximately half of the inner circumferential side of the action portion 14 is formed with a relief recess 14b that is open rearward and in the direction of the optical axis P.

[0059] The lens 8A, which is positioned at the frontmost side, is held inside the lens holding ring 4 (see FIGS. 2 to 4). The lens 8A is a convex lens made of, for example, a glass material, with one surface (front surface) in the optical axis direction formed as a convex surface and the other surface (rear surface) in the optical axis direction formed as a flat surface.

[0060] The outer periphery of lens 8A is formed as edge portion 15, the front surface of edge portion 15 is formed as pressed surface 16, and the rear surface of edge portion 15 is formed as received surface 17. The outer periphery of pressed surface 16 is formed as inclined portion 16a, which is inclined with respect to the optical axis direction and a direction perpendicular to the optical axis direction, and is inclined so as to approach received surface 17 as it approaches outer periphery surface 8a of lens 8A in the radial direction.

[0061] The lens 8A is held inside the lens holding ring 4 with its edge 15 pressed in the optical axis direction by the pressing ring 12 via an elastic member 18. The elastic member 18 is formed into a circular ring shape from, for example, a rubber material. The diameter of the elastic member 18 is approximately the same as the diameter of the lens 8A, and the cross-sectional shape when not elastically deformed is formed into, for example, a circular shape.

[0062] The lens 8A is held inside the lens retaining ring 4 in a state where it is sandwiched between the pressing ring 12 and the lens retaining ring 4 via an annular first sheet 19, an annular second sheet 20, and an elastic member 18 (see FIGS. 3 and 4). The first sheet 19 is disposed between the action portion 14 of the pressing ring 12 and the elastic member 18, and the second sheet 20 is disposed between the lens 8A and the receiving protrusion 9 of the lens retaining ring 4, and the elastic member 18 is pressed against the member receiving surface 10d of the lens retaining ring 4 and the inclined portion 16a of the lens 8A.

[0063] Since the second sheet 20 is disposed between the lens 8A and the receiving protrusion 9 of the lens retaining ring 4, it is possible to adjust the position of the lens 8A in the optical axis direction by changing its thickness. Therefore, by disposing the required number of second sheets 20 inside the lens retaining ring 4, it is possible to adjust the position of the lens 8A in the optical axis direction to an appropriate position.

[0064] In the lens barrel 1, adjustment of the lens 8A in a direction perpendicular to the optical axis direction is performed by adjustment screws 21 (see FIGS. 2 to 4). Through adjustment, the optical axis of the lens 8A is aligned with that of other lenses 8, etc. The adjustment screw 21 is formed, for example, from an elastically deformable resin material, and is screwed into a threaded hole 10a formed in the lens holding ring 4 by a tool such as a screwdriver.

[0065] By threading the adjustment screw 21 into the screw hole 10a, the tip surface 21a of the adjustment screw 21 comes into contact with the outer peripheral surface 8a of the lens 8A, and the lens 8A is displaced in a direction perpendicular to the optical axis direction depending on the threaded position of the adjustment screw 21 relative to the screw hole 10a, thereby adjusting the lens 8A in the direction perpendicular to the optical axis direction. After adjustment, the outer peripheral surface 8a of the lens 8A is positioned away from the lens-opposing surface 10c of the hole forming portion 10 in the direction perpendicular to the optical axis direction.

[0066] When adjustment in a direction perpendicular to the optical axis direction of the lens 8A is completed, the filling recess 10b formed in the hole forming section 10 is filled with adhesive (not shown), the adjustment screw 21 is fixed to the hole forming section 10, and the lens 8A is held in the position where adjustment is completed.

[0067] As described above, in the lens barrel 1, a plurality of screw holes 10a are formed in the lens holding ring 4 at intervals in the circumferential direction, and an adjustment screw 21 whose tip surface 21a contacts the outer peripheral surface 8a of the lens 8A is screwed into the screw holes 10a, and the position of the adjustment screw 21 in a direction perpendicular to the optical axis direction of the lens 8A is adjusted by the screwing position of the adjustment screw 21 relative to the screw hole 10a.

[0068] Therefore, since the position of the lens 8A in a direction perpendicular to the optical axis direction is adjusted by the plurality of adjustment screws 21, the position of the optical axis of the lens 8A can be easily and reliably adjusted.

[0069] Furthermore, since the adjustment screws 21 are formed from an elastically deformable resin material, the multiple adjustment screws 21 are elastically deformable when an impact is applied to the lens 8A via the outer tube 2 or the like, and the impact is absorbed by the adjustment screws 21, thereby preventing damage to the lens 8A, misalignment, or distortion.

[0070] Furthermore, because the outer peripheral surface 8a of the lens 8A and the inner peripheral surface of the lens retaining ring 4 are kept out of contact, the outer peripheral surface 8a of the lens 8A is less likely to come into contact with the lens retaining ring 4 when an impact is applied, preventing damage to the lens 8A. Even if an environmental change causes the lens 8A and the lens retaining ring 4 to expand or contract, the outer peripheral surface 8a of the lens 8A and the inner peripheral surface of the lens retaining ring 4 are kept out of contact, preventing distortion of the lens 8A.

[0071] As described above, in the lens barrel 1, the lens retaining ring 4 is made of a metal material, the lens 8A is made of a glass material, and the adjustment screw 21 is made of a resin material, and the linear expansion coefficient of the adjustment screw 21 is made larger than that of the lens retaining ring 4, which is made larger than that of the lens 8A.

[0072] <Lens holding work> The operation of holding the lens 8A will be described below (see FIGS. 3 and 4).

[0073] In the operation of holding the lens 8A, first, the second sheet 20 is inserted into the lens retaining ring 4 from the front side, and then the lens 8A is inserted into the lens retaining ring 4 from the front side. The second sheet 20 is pressed against the lens receiving surface 9a of the receiving protrusion 9 on the lens retaining ring 4, and the receiving surface 17 of the lens 8A is pressed against the second sheet 20.

[0074] Next, the elastic member 18 is inserted into the lens retaining ring 4 from the front side, and then the first sheet 19 is inserted into the lens retaining ring 4 from the front side. The elastic member 18 is pressed against the member receiving surface 10d of the lens retaining ring 4 and the inclined portion 16a of the lens 8A, and the first sheet 19 is pressed against the elastic member 18 and the sheet receiving surface 10f of the hole forming portion 10.

[0075] Next, the presser ring 12 is inserted into the lens retaining ring 4 from the front side, and the presser ring 12 is coupled to the lens retaining ring 4. The presser ring 12 is inserted into the lens retaining ring 4 by rotating the presser ring 12 about its axis and threading the threaded portion 12a into the threaded groove portion 11a of the coupling portion 11. When the presser ring 12 is rotated about its axis and inserted into the lens retaining ring 4, the first sheet 19 is pressed from the front by the presser surface 14a of the presser ring 12, and the first sheet 19 is pressed against the sheet receiving surface 10f, and the presser surface 14a is pressed against the elastic member 18 via the first sheet 19.

[0076] At this time, the rotating presser ring 12 slides smoothly against the first sheet 19, ensuring smooth rotation of the presser ring 12.

[0077] The elastic member 18, against which the pressing surface 14a is pressed via the first sheet 19, is elastically deformed and is pressed in an elastically deformed state against the member receiving surface 10d of the lens holding ring 4 and the inclined portion 16a of the lens 8A. Therefore, the lens 8A is pressed from the front by the elastic member 18, and the received surface 17 is pressed against the lens receiving surface 9a of the receiving protrusion 9 via the second sheet 20.

[0078] At this time, the pressing ring 12 is joined to the lens retaining ring 4 with the acting portion 14 not in contact with the pressed surface 16 of the lens 8A, and a gap S is formed between the pressing ring 12 and the lens 8A. In particular, the pressing ring 12 is formed with a relief recess 14b, which reliably prevents contact between the pressing ring 12 and the lens 8A. The pressing ring 12 joined to the lens 8A is placed in a state where the maximum diameter portion 13 is positioned in front of the lens retaining ring 4.

[0079] As described above, the pressing ring 12 and the lens retaining ring 4 are joined, the elastic member 18 is pressed against the lens 8A by the pressing ring 12 via the first sheet 19, and the lens 8A is pressed against the lens receiving surface 9a of the lens retaining ring 4 via the second sheet 20, thereby completing the holding operation of the lens 8A. When the holding operation of the lens 8A is completed, the lens 8A is sandwiched in the optical axis direction between the pressing ring 12 and the lens retaining ring 4 via the elastic member 18, the first sheet 19, and the second sheet 20.

[0080] Furthermore, the adjustment of lens 8A in the direction perpendicular to the optical axis direction using the above-mentioned adjustment screws 21, 21, ... is performed after the holding operation of lens 8A is completed. At this time, as adjustment screw 21 rotates, lens 8A is displaced in the direction perpendicular to the optical axis, but lens 8A slides smoothly relative to second sheet 20.

[0081] <Summary> As described above, the imaging device 100 and the lens barrel 1 are provided with a lens retaining ring 4 having a lens receiving surface 9a that receives the receiving surface 17 of the lens 8A, an elastic member 18 that is pressed against the pressed surface 16 of the lens 8A, and a pressing ring 12 that is movable in the optical axis direction relative to the lens retaining ring 4 and has a pressing surface 14a that presses the elastic member 18 from the optical axis direction, thereby pressing the lens 8A against the lens receiving surface 9a via the elastic member 18.

[0082] Therefore, elastic member 18 is pressed by press ring 12 from the optical axis direction, and elastic member 18 is pressed against pressed surface 16 of lens 8A, and received surface 17 of lens 8A is received by lens receiving surface 9a of lens holding ring 4, so press ring 12 can hold lens 8A without contacting lens 8A. As a result, when an impact or the like is applied to lens barrel 1, the impact transmitted from press ring 12 to lens 8A is reduced by elastic member 18, reducing the external load on lens 8A and ensuring good optical performance.

[0083] Furthermore, since the lens 8A is pressed by the pressing ring 12 via the elastic member 18, it is possible to suppress the occurrence of distortion in the lens 8A. In particular, in the case of a lens 8A whose edge 15 is thinner than the other parts, the pressing force tends to concentrate on the edge 15, which tends to cause distortion, so a high effect can be obtained by pressing the lens 8A whose edge 15 is thinner than the other parts via the elastic member 18.

[0084] Furthermore, the elastic member 18 is pressed against the lens 8A in an elastically deformed state between the pressing ring 12 and the lens 8A, and even if a change in the environment occurs and the gap S between the pressing ring 12 and the lens 8A changes due to a difference in the linear expansion coefficient, the degree of elastic deformation of the elastic member 18 changes, but the state in which the elastic member 18 is pressed against the lens 8A is maintained, so a stable holding state of the lens 8A can be ensured regardless of changes in the environment.

[0085] Furthermore, the lens holding ring 4 is formed with a member receiving surface 10 d for receiving the elastic member 18 , and the elastic member 18 is pressed against the member receiving surface 10 d and the pressed surface 16 .

[0086] Therefore, since the elastic member 18 is pressed against a part of the pressing ring 12, a part of the lens 8A, and a part of the lens holding ring 4 in three directions, the elastic member 18 can be placed inside the lens holding ring 4 in a stable state.

[0087] Furthermore, since the elastic member 18 is formed in a ring shape, the pressing force of the pressing ring 12 is more easily applied evenly to the outer periphery of the lens 8A via the elastic member 18, and therefore, a more stable holding state of the lens 8A using the lens holding ring 4 and the pressing ring 12 can be ensured.

[0088] Furthermore, an inclined portion 16a inclined with respect to the optical axis direction and a direction perpendicular to the optical axis direction is formed on the pressed surface 16, and an elastic member 18 is pressed against the inclined portion 16a.

[0089] Therefore, the lens 8A is held in a state in which the elastic member 18 is pressed against the inclined portion 16a that is inclined in the optical axis direction and in a direction perpendicular to the optical axis direction, so that impacts in the optical axis direction and in a direction perpendicular to the optical axis direction are absorbed by the elastic member 18, thereby preventing displacement and distortion of the lens 8A.

[0090] In addition, when the pressing ring 12 is rotated around the axis, it is moved in the optical axis direction relative to the lens holding ring 4, and a ring-shaped first sheet 19 is placed between the pressing ring 12 and the elastic member 18, and the pressing ring 12 is pressed against the elastic member 18 via the first sheet 19.

[0091] Therefore, when rotating around the axis, the retaining ring 12 slides against the first sheet 19, allowing the retaining ring 12 to rotate smoothly relative to the lens retaining ring 4, ensuring good assembly of the retaining ring 12 to the lens retaining ring 4.

[0092] Furthermore, an annular second sheet 20 is disposed between the lens receiving surface 9a and the receiving surface 17, and the lens 8A is pressed against the lens receiving surface 9a via the second sheet 20.

[0093] Therefore, when adjusting using the adjustment screw 21, the lens 8A slides against the second sheet 20, so that the lens 8A is smoothly displaced relative to the lens holding ring 4, and the position of the lens 8A can be easily and accurately adjusted in a direction perpendicular to the optical axis direction.

[0094] In addition, the linear expansion coefficient of the adjusting screw 21 is set to be larger than that of the lens holding ring 4, which in turn is set to be larger than that of the lens 8A.

[0095] Therefore, when the lens barrel 1 is used in a high temperature environment, even if the gap between the outer peripheral surface 8a of the lens 8A and the inner peripheral surface of the lens holding ring 4 becomes large, the tip surface 21a of the adjustment screw 21 remains in contact with the outer peripheral surface 8a of the lens 8A, thereby preventing the lens 8A from rattling.

[0096] On the other hand, when the lens barrel 1 is used in a low-temperature environment, even if the gap between the outer peripheral surface 8a of the lens 8A and the inner peripheral surface of the lens retaining ring 4 becomes small, the contraction rate of the adjustment screw 21 is greater than that of the lens retaining ring 4, so that excessive load is not applied to the lens 8A from the adjustment screw 21, preventing deformation or cracking of the lens 8A.

[0097] <Other> The above shows an example of an elastic member 18 whose cross-sectional shape when not elastically deformed is circular, but the cross-sectional shape of the elastic member 18 is not limited to a circular shape and may be formed in various shapes.

[0098] For example, an elastic member 18A having a flat portion may be used instead of the elastic member 18 (see FIG. 6). The elastic member 18A has both front and rear surfaces formed as flat portions 18a, 18b facing the optical axis direction. When the elastic member 18A is used, the member receiving surface 10d of the hole forming portion 10 in the lens holding ring 4 is formed so as to face the optical axis direction, and the pressing surface 14a of the action portion 14 in the pressing ring 12 is formed so as to face the optical axis direction. One flat portion 18a of the elastic member 18A is pressed by the pressing surface 14a, and the other flat portion 18b is pressed against the member receiving surface 10d.

[0099] In this way, an elastic member 18A is used, which is formed with flat surfaces 18a and 18b on both sides facing the optical axis direction, and the flat surface 18a is pressed against the pressing surface 14a facing the optical axis direction, and the flat surface 18b is pressed against the member receiving surface 10d facing the optical axis direction, thereby increasing the contact area of ​​the elastic member 18A with the lens retaining ring 4 and the pressing ring 12.

[0100] Therefore, when the pressing ring 12 is rotated about the axis relative to the lens holding ring 4 and the elastic member 18 is pressed by the pressing surface 14a, deformation such as a portion of the elastic member 18A being displaced inward is unlikely to occur, and the elastic member 18 can be prevented from shifting out of position relative to the lens 8A.

[0101] <One embodiment of the imaging device> An example of the configuration of an embodiment of an imaging device according to the present technology will be described below (see FIG. 7).

[0102] Imaging device 100 has a lens barrel 1 that performs imaging functions, a camera signal processing unit 81 that performs signal processing such as analog-to-digital conversion of captured image signals, and an image processing unit 82 that performs recording and playback processing of image signals. Imaging device 100 also has a display unit (display) 83 that displays captured images, etc., an R / W (reader / writer) 84 that writes and reads image signals to memory 90, a CPU (Central Processing Unit) 85 that controls the entire imaging device 100, an operation unit 202 such as various switches that are operated as required by the user, and a lens drive control unit 86 that controls the drive of the lens arranged in lens barrel 1.

[0103] The imaging device 100 is provided with an imaging element 204 such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal-Oxide Semiconductor) that converts an optical image captured by the lens barrel 1 into an electrical signal.

[0104] The camera signal processing unit 81 performs various signal processing on the output signal from the image sensor 204, such as converting it into a digital signal, removing noise, correcting image quality, and converting it into a luminance and color difference signal.

[0105] The image processing unit 82 performs processes such as compression encoding, decompression decoding of image signals based on a predetermined image data format, and conversion of data specifications such as resolution.

[0106] The display unit 83 has a function of displaying various data such as the operating status of the user on the operation unit 202 and captured images. Note that the imaging device 100 does not necessarily have to be provided with the display unit 83, and may be configured so that captured image data is sent to another display device and the image is displayed thereon.

[0107] The R / W 84 writes image data encoded by the image processing unit 82 into the memory 90 and reads image data recorded in the memory 90 .

[0108] The CPU 85 functions as a control processing unit that controls each circuit block provided in the image pickup device 100, and controls each circuit block based on an instruction input signal from the operation unit 202 or the like.

[0109] The operation unit 202 outputs to the CPU 85 an instruction input signal in response to an operation by the user.

[0110] The lens drive control unit 86 controls the drive source that moves the lens based on a control signal from the CPU 85 .

[0111] The memory 90 is, for example, a semiconductor memory that is detachable from a slot connected to the R / W 84 .

[0112] The operation of the imaging device 100 will be described below.

[0113] In a standby state for photographing, a photographed image signal is output to the display unit 83 via the camera signal processing unit 81 under the control of the CPU 85, and is displayed as a camera-through image. Furthermore, when an instruction input signal is input from the operation unit 202, the CPU 85 outputs a control signal to the lens drive control unit 86, and the lens is moved under the control of the lens drive control unit 86.

[0114] When a photographing operation is performed in response to an instruction input signal from the operation unit 202, the photographed image signal is output from the camera signal processing unit 81 to the image processing unit 82, 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 84 and written to the memory 90.

[0115] When image data recorded in memory 90 is to be reproduced, predetermined image data is read from memory 90 by R / W 84 in response to an operation on operation unit 202, and after expansion and decoding processing is performed by image processing unit 82, the reproduced image signal is output to display unit 83 and the reproduced image is displayed.

[0116] In the present technology, "imaging" refers to processing that includes only a part or all of a series of processing, from photoelectric conversion processing that converts light captured by the image sensor 204 into an electrical signal, to processing by the camera signal processing unit 81 that converts the output signal from the image sensor 204 into a digital signal, noise removal, image quality correction, conversion into luminance and color difference signals, etc., to compression, encoding, decompression and 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 82, and writing processing of the image signal to the memory 90 by the R / W 84.

[0117] That is, "imaging" may refer only to the photoelectric conversion process of converting the light captured by the image sensor 204 into an electrical signal, or may refer to the process from the photoelectric conversion process of converting the light captured by the image sensor 204 into an electrical signal to the process of converting the output signal from the image sensor 204 into a digital signal by the camera signal processing unit 81, noise removal, image quality correction, conversion into luminance and color difference signals, etc. ... to the process of converting the output signal from the image sensor 204 into a digital signal by the camera signal processing unit 81, noise removal, image quality correction, conversion into luminance and color difference signals, etc., to the process of converting the output signal from the image sensor 204 into a digital signal by the camera signal processing unit 81, noise removal, image quality correction, conversion into luminance and color difference signals, etc., to the process of converting the output signal from the image sensor 204 into a 2, and conversion of data specifications such as resolution, or may refer to processes from the photoelectric conversion process of converting captured light by the image sensor 204 into an electrical signal to the camera signal processing unit 81, conversion of the output signal from the image sensor 204 into a digital signal, noise removal, image quality correction, conversion to luminance and color difference signals, and the like, and also to the compression coding, expansion decoding process of the image signal based on a predetermined image data format and conversion of data specifications such as resolution, or may refer to the process up to the writing of the image signal to memory 90 by R / W 84. The order of each process in the above processes may be reversed as appropriate.

[0118] Furthermore, in the present technology, the lens barrel 1 and the photographing device 100 may be configured to include only some or all of the image sensor 204, camera signal processing unit 81, image processing unit 82, and R / W 84 that perform the above processing.

[0119] Alternatively, the lens barrel 1 may include some of the image sensor 204, camera signal processor 81, image processor 82, and R / W 84, and the device body 200 may include the rest.

[0120] <This technology> The present technology can also be configured as follows.

[0121] (1) a lens having an outer periphery with one surface formed as a receiving surface and the other surface formed as a pressing surface in the optical axis direction; a lens holding ring having a lens receiving surface that receives the receiving surface; an elastic member pressed against the pressed surface; a pressing ring that is movable in the optical axis direction relative to the lens holding ring and has a pressing surface that presses the elastic member from the optical axis direction, and presses the lens against the lens receiving surface via the elastic member; Lens barrel.

[0122] (2) a member receiving surface for receiving the elastic member is formed on the lens holding ring; The elastic member is pressed against the member receiving surface and the pressed surface. The lens barrel according to (1) above.

[0123] (3) The elastic member is formed in a ring shape. The lens barrel according to (1) or (2) above.

[0124] (4) an inclined portion inclined with respect to the optical axis direction and a direction perpendicular to the optical axis direction is formed on the pressed surface; The elastic member is pressed against the inclined portion. The lens barrel according to any one of (1) to (3) above.

[0125] (5) The outer peripheral surface of the lens and the inner peripheral surface of the lens holding ring are kept in a non-contact state. The lens barrel according to any one of (1) to (4).

[0126] (6) The pressing ring is rotated about its axis to move in the optical axis direction relative to the lens holding ring, an annular first sheet is disposed between the pressing ring and the elastic member; The pressing ring is pressed against the elastic member via the first sheet. The lens barrel according to any one of (1) to (5) above.

[0127] (7) the elastic member has two flat surfaces on both sides thereof facing the optical axis direction, a member receiving surface for receiving the elastic member is formed on the lens holding ring; The member receiving surface is formed to face the optical axis direction, The pressing surface is formed to face the optical axis direction, One of the flat surfaces of the elastic member is pressed against the pressing surface, and the other flat surface is pressed against the member receiving surface. The lens barrel according to any one of (1) to (6) above.

[0128] (8) A plurality of screw holes are formed in the lens holding ring at intervals in the circumferential direction, an adjustment screw whose tip surface contacts the outer peripheral surface of the lens is screwed into the screw hole; The position of the lens in a direction perpendicular to the optical axis direction is adjusted by the screwing position of the adjustment screw with respect to the screw hole. The lens barrel according to any one of (1) to (7) above.

[0129] (9) The adjusting screw is made of an elastically deformable resin material. The lens barrel according to (8) above.

[0130] (10) an annular second sheet is disposed between the lens receiving surface and the receiving surface; The lens is pressed against the lens receiving surface via the second sheet. The lens barrel according to any one of (1) to (9) above.

[0131] (11) The linear expansion coefficient of the adjustment screw is set to be larger than the linear expansion coefficient of the lens holding ring, The linear expansion coefficient of the lens holding ring is larger than the linear expansion coefficient of the lens. The lens barrel according to (8) or (9) above.

[0132] (12) The camera includes a lens barrel that captures an optical image and an image sensor that converts the captured optical image into an electrical signal. The lens barrel comprises: a lens having an outer periphery with one surface formed as a receiving surface and the other surface formed as a pressing surface in the optical axis direction; a lens holding ring having a lens receiving surface that receives the receiving surface; an elastic member pressed against the pressed surface; a pressing ring that is movable in the optical axis direction relative to the lens holding ring and has a pressing surface that presses the elastic member from the optical axis direction, and presses the lens against the lens receiving surface via the elastic member; Imaging device. [Explanation of symbols]

[0133] 100...imaging device, 204...imaging element, 1...lens barrel, 4...lens holding ring, 8A...lens, 8a...outer circumferential surface, 9a...lens receiving surface, 10a...screw hole, 10d...member receiving surface, 12...pressing ring, 14a...pressing surface, 16...pressed surface, 16a...inclined portion, 17...received surface, 18...elastic member, 19...first sheet, 20...second sheet, 21...adjusting screw, 21a...tip surface, 18A...elastic member, 18a...flat portion, 18b...flat portion

Claims

1. a lens having an outer periphery with one surface formed as a receiving surface and the other surface formed as a pressing surface in the optical axis direction; a lens holding ring having a planar lens receiving surface extending in a circumferential direction and receiving the receiving surface; an elastic member pressed against the pressed surface; a pressing ring that is movable in the optical axis direction relative to the lens holding ring and has a pressing surface that presses the elastic member in the optical axis direction, and presses the lens against the lens receiving surface via the elastic member; the lens holding ring is formed with a lens facing surface positioned opposite to an outer peripheral surface of the lens, and a member receiving surface facing in a direction different from the lens facing surface and receiving the elastic member; The elastic member is pressed against the member receiving surface and the pressed surface, The lens is held by being clamped in the optical axis direction, The outer peripheral surface of the lens and the inner peripheral surface of the lens holding ring are kept in a non-contact state, A plurality of screw holes are formed in the lens holding ring at intervals in the circumferential direction, an adjustment screw formed of an elastically deformable resin material and having a tip surface in contact with the outer peripheral surface of the lens is screwed into the screw hole; a position of the lens in a direction perpendicular to the optical axis direction is adjusted by a screwing position of the adjustment screw with respect to the screw hole; the elastic member has two flat surfaces on both sides thereof facing the optical axis direction, The member receiving surface is formed to face the optical axis direction, The pressing surface is formed to face the optical axis direction, One of the flat surfaces of the elastic member is pressed against the pressing surface, and the other flat surface is pressed against the member receiving surface. Lens barrel.

2. The elastic member is formed in a ring shape. The lens barrel according to claim 1 .

3. an inclined portion inclined with respect to the optical axis direction and a direction perpendicular to the optical axis direction is formed on the pressed surface; The elastic member is pressed against the inclined portion. The lens barrel according to claim 1 .

4. The pressing ring is rotated about its axis to move in the optical axis direction relative to the lens holding ring, an annular first sheet is disposed between the pressing ring and the elastic member; The pressing ring is pressed against the elastic member via the first sheet. The lens barrel according to claim 1 .

5. an annular second sheet is disposed between the lens receiving surface and the receiving surface; The lens is pressed against the lens receiving surface via the second sheet. The lens barrel according to claim 1 .

6. The linear expansion coefficient of the adjustment screw is set to be larger than the linear expansion coefficient of the lens holding ring, The linear expansion coefficient of the lens holding ring is larger than the linear expansion coefficient of the lens. The lens barrel according to claim 1 .

7. The camera includes a lens barrel that captures an optical image and an image sensor that converts the captured optical image into an electrical signal. The lens barrel comprises: a lens having an outer periphery with one surface formed as a receiving surface and the other surface formed as a pressing surface in the optical axis direction; a lens holding ring having a planar lens receiving surface extending in a circumferential direction and receiving the receiving surface; an elastic member pressed against the pressed surface; a pressing ring that is movable in the optical axis direction relative to the lens holding ring and has a pressing surface that presses the elastic member in the optical axis direction, and presses the lens against the lens receiving surface via the elastic member; the lens holding ring is formed with a lens facing surface positioned opposite to an outer peripheral surface of the lens, and a member receiving surface facing in a direction different from the lens facing surface and receiving the elastic member; The elastic member is pressed against the member receiving surface and the pressed surface, The lens is held by being clamped in the optical axis direction, The outer peripheral surface of the lens and the inner peripheral surface of the lens holding ring are kept in a non-contact state, A plurality of screw holes are formed in the lens holding ring at intervals in the circumferential direction, an adjustment screw formed of an elastically deformable resin material and having a tip surface in contact with the outer peripheral surface of the lens is screwed into the screw hole; a position of the lens in a direction perpendicular to the optical axis direction is adjusted by a screwing position of the adjustment screw with respect to the screw hole; the elastic member has two flat surfaces on both sides thereof facing the optical axis direction, The member receiving surface is formed to face the optical axis direction, The pressing surface is formed to face the optical axis direction, One of the flat surfaces of the elastic member is pressed against the pressing surface, and the other flat surface is pressed against the member receiving surface. Imaging device.

Images