JP2016130765A - Lens barrel, optical device, and imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens barrel capable of improving optical performance with high shock resistance.SOLUTION: The lens barrel includes: a lens holding frame which holds a lens; a straight advance barrel capable of performing straight movement while holding the lens holding frame; and a first cam follower and a second cam follower which are disposed in a cam groove on the straight advance barrel. The first cam follower is capable of adjusting the position of the lens holding frame. The second cam follower is arranged so as to come into contact with the cam groove to thereby reduce deformation of the first cam follower when an external force is applied thereto.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a lens barrel used in an optical apparatus.

  In a lens barrel used in an optical device such as a digital camera or a video camera, when the lens holding member for holding the lens group is incorporated into the lens barrel body, the inclination of the lens group and the optical axis are decentered to remove the lens group. Optical adjustment is performed.

  Patent Document 1 discloses a lens barrel that adjusts the tilt of a lens by an eccentric roller and adjusts the position of an optical element in the optical axis direction by rotating a holding member by guiding a cam groove. Patent Document 2 discloses a lens barrel in which a lens holding member is fixed to a lens barrel body using an adhesive filled around a pin member attached through a plurality of through holes. .

JP 2006-91153 A JP 2010-191070 A

  In the lens barrel of Patent Document 1, an eccentric roller made of a circular resin material or metal material is used. When an eccentric roller made of resin material is used, the lens holding frame adjustment state may change due to the deformation of the eccentric roller due to the impact of the impact of the lens barrel or the rotation of the eccentric roller. There is. On the other hand, when an eccentric roller made of a metal material is used, it is necessary to provide a backlash between the cam groove and the eccentric roller in order to prevent twisting with the cam groove. However, at this time, if the sensitivity of the lens held by the lens holding frame or the sensitivity of the entire lens barrel is high, the desired optical performance cannot be satisfied.

  In the lens barrel of Patent Document 2, when an impact (external force) is applied to the lens barrel, the lens barrel is not subjected to a load only with an eccentric roller, but is subjected to a load with an adhesive filled around the pin member. For this reason, when an external force is applied, the eccentric roller is not easily rotated or deformed by the dent, and the shift of the adjustment position can be reduced. However, in the case of a heavy lens barrel, there is a possibility that the deformation due to the dent of the roller will occur and the optical performance will deteriorate.

  Therefore, the present invention provides a lens barrel, an optical apparatus, and an imaging apparatus that have high impact resistance and improved optical performance.

  A lens barrel according to an aspect of the present invention includes a lens holding frame that holds a lens, a rectilinear cylinder that holds the lens holding frame and can move linearly, and a cam barrel of the rectilinear cylinder. The first cam follower is capable of adjusting the position of the lens holding frame, and the second cam follower contacts the cam groove when an external force is applied. In contact with the first cam follower, the deformation of the first cam follower is reduced.

  An optical apparatus according to another aspect of the present invention includes the lens barrel.

  An imaging apparatus according to another aspect of the present invention includes the lens barrel and an imaging element that photoelectrically converts an optical image formed via the optical system of the lens barrel and outputs image data.

  Other objects and features of the invention are described in the following embodiments.

  According to the present invention, it is possible to provide a lens barrel, an optical apparatus, and an imaging apparatus that have high impact resistance and improved optical performance.

It is sectional drawing of the lens-barrel in 1st Embodiment. It is sectional drawing of the rectilinear cylinder in 1st Embodiment. It is a disassembled perspective view of the principal part of the lens barrel in 1st Embodiment. It is a side view of the rectilinear cylinder and 1st group holding frame in 1st Embodiment. It is sectional drawing of the 1st group holding | maintenance frame (1st cam follower) in 1st Embodiment. It is sectional drawing of the 1st group holding | maintenance frame (2nd cam follower) in 1st Embodiment. It is detail drawing of the 2nd cam follower in 1st Embodiment. It is detail drawing of the 2nd cam follower in 2nd Embodiment. It is detail drawing of the 1st group holding | maintenance frame in 2nd Embodiment. It is a disassembled perspective view of the principal part of the lens barrel in 3rd Embodiment. It is detail drawing of the 2nd cam follower in 3rd Embodiment. It is a block diagram of the optical instrument (imaging device) in 4th Embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
First, the overall configuration of the lens barrel in the first embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is a cross-sectional view of a lens barrel 1 in the present embodiment. FIG. 2 is a cross-sectional view of the rectilinear cylinder 3 in the lens barrel 1. FIG. 3 is an exploded perspective view of the main part of the lens barrel 1.

  Reference numeral 1 denotes a lens barrel that is detachably attached to a camera body (imaging device body). The mount 19 has a bayonet portion for attaching the lens barrel 1 to the camera body. The lens barrel 1 has a plurality of lens groups including a first lens group L1, a second lens group L2, and a third lens group L3 in order from the object side to the image plane side. The first lens group L1, the second lens group L2, and the third lens group L3 are variable power lens groups (zoom lenses) that move in the direction of the optical axis OA (optical axis direction) during zoom operation. Among these lens groups, the second lens group L2 is a focusing lens group (focus lens) that moves in the optical axis direction during the focusing operation.

  The flange back adjustment ring 21 is sandwiched between the fixed cylinder 18 and the mount 19 and is fixed to the fixed cylinder 18 together with the mount 19 using screws. Reference numeral 4 denotes a guide cylinder, which is fixed to the fixed cylinder 18 using screws. A cam cylinder 5 that is rotatable about the optical axis OA is fitted to the inner periphery of the guide cylinder 4 by a bayonet portion 5a.

  3 is a straight cylinder. A first group holding frame 10 that holds the first lens group L1 is held by the roller 10a on the rectilinear cylinder 3. The rectilinear cylinder 3 has a sliding surface 3 c on the inner periphery on the image plane side, and is fitted to the sliding surface 4 b of the guide cylinder 4 so as to be movable with respect to the guide cylinder 4. The rectilinear cylinder 3 holds the three key members 17 provided in the circumferential direction with screws 17a, and engages the key member 17 with the rectilinear grooves 4c formed on the outer periphery of the cam cylinder 4, so that the optical axis It is held so that it can move straight in the direction.

  As shown in FIG. 2, a bottomed first group cam 3 a is provided on the inner periphery of the rectilinear cylinder 3, and the first group cam 3 a has a roller fixed to the outer periphery of the distal end of the cam cylinder 5 with screws 5 c. 5b is engaged. In such a configuration, as the cam cylinder 5 rotates, the rectilinear cylinder 3 moves straight along the locus of the first group cam 3a. The first group holding frame 10 is fixed so that the roller 10 a is adjusted in position in the optical axis direction by a cam groove 3 b having a lift of the rectilinear cylinder 3, and can move integrally with the rectilinear cylinder 3.

  Reference numeral 2 denotes an adjustment cylinder having a plurality of cylindrical portions whose diameters increase from the image plane side toward the object side with the optical axis OA as the center. Each of the plurality of cylindrical portions is connected by a disk-shaped flange portion, and is fixed to the guide tube 4 with screws from the optical axis direction at the flange-shaped small diameter portion. The adjustment cylinder 2 can be eccentrically adjusted in the optical axis direction with respect to the guide cylinder 4, and the entire system optical axis adjustment in the lens barrel 1 can be performed. The rectilinear cylinder 3 has a flange shape, and the roller shaft 12 is engaged with three engagement grooves formed in the large diameter portion of the flange, so that the roller 13 can move in the optical axis direction. Is fixed to the straight cylinder 3 with screws. A roller shaft urging spring (not shown) urges the roller shaft 12 in a direction perpendicular to the optical axis OA (a direction perpendicular to the optical axis), and the roller 13 is always urged against the rectilinear cylinder 3. .

  Reference numeral 23 denotes a focus cam cylinder. The focus cam cylinder 23 is formed with a cam groove. Reference numeral 22 denotes a second group holding frame that holds the second lens group L2 as the focusing lens group. The second group holding frame 22 has a cam follower portion provided on the outer periphery thereof engaged with a focus cam groove formed in the focus cam cylinder 23. Reference numeral 24 denotes a third group holding frame that holds the third lens group L3.

  A rear group holding frame 26 holds the second group holding frame 22 and the third group holding frame 24. The focus cam cylinder 23 is held between the rear group holding frame 26 and the focus cam cylinder holding sheet metal 27 and is held by the rear group holding frame 26 by screwing the focus cam cylinder holding sheet metal 27 to the rear group holding frame 26. The The rear group holding frame 26 is held by engaging a roller (not shown) with a cam groove formed in the cam cylinder 5. When the cam cylinder 5 is rotated, the intersection of the rectilinear groove formed in the guide cylinder 4 extending in the optical axis direction and the rear group cam groove and rectilinear cylinder cam groove formed in the cam cylinder 5 moves. As the intersection moves, the rear group holding frame 26 and the rectilinear cylinder 3 linearly move in the optical axis direction through the respective moving rollers.

  Reference numeral 30 denotes a main aperture unit (electromagnetic aperture unit) for performing light amount adjustment for determining an aperture value (F value). The main aperture unit 30 is disposed on the inner diameter of the focus cam cylinder 23 and is held at the inner diameter of the focus cam cylinder 23 by screwing the focus cam cylinder presser metal plate 27 to the rear group holding frame 26. Reference numeral 31 denotes a first sub-aperture unit that corrects an open aperture diameter by a zoom operation. The first sub diaphragm unit 31 is arranged on the object side in the optical axis direction with respect to the main diaphragm unit 30. The first sub-aperture 31 unit is fixed and held with respect to the sub-aperture holding cylinder 32 using screws (not shown). The sub diaphragm holding cylinder 32 is held by the cam cylinder 5 with a roller (not shown) engaged with a cam groove formed in the cam cylinder 5. Reference numeral 33 denotes a second sub-aperture unit for preventing a large change in the amount of peripheral light due to the zoom operation. The second sub-aperture unit 33 is disposed rearward (image plane side) in the optical axis direction with respect to the main aperture unit 30 and is held on the rear group holding frame 26 by screws (not shown).

  A focus unit 28 is fixed to the guide cylinder 4 with screws. Reference numeral 15 denotes a manual ring, which is held so as to be rotatable at a fixed position with respect to the focus unit 28. The focus unit 28 mainly includes a vibration type motor and a differential mechanism, and outputs a rotation amount corresponding to the rotor rotation amount of the vibration type motor and the rotation amount of the manual ring 15 to a focus key (not shown). . The focus key is engaged with a focus key engagement groove formed in the focus cam cylinder 23. The focus key is rotated by rotating the manual ring 15 during manual focus and by rotating the manual ring 15 during manual focus. As a result, the second lens unit L2 held by the second group holding frame 22 can advance and retract in the optical axis direction along the locus of the cam groove formed in the focus cam cylinder 23, and focusing can be performed.

  Reference numeral 20 denotes a zoom ring. The zoom ring 20 is a member that is rotated by a user during a zoom operation, and is held so as to be rotatable at a fixed position with respect to the fixed cylinder 18. A zoom key (not shown) is fixed to the zoom ring 20 with screws. The zoom key is engaged with a zoom key engagement groove formed in the cam cylinder 5. When the zoom ring 20 is rotated, the cam cylinder 5 can be integrally rotated via the zoom key by the rotational force.

  Reference numeral 6 denotes a lens hood, which has a flange shape having a plurality of cylindrical portions whose diameters increase from the image plane side toward the object side around the optical axis OA. The lens hood 6 contacts the adjustment cylinder 2 on the object side surface in the optical axis direction, and contacts the wave washer 7 (first elastic member) on the image surface side surface. The wave washer 7 is sandwiched between the lens hood 6 and the fixing ring member 9 fixed to the adjustment cylinder 2 with screws. Reference numeral 8 denotes a rubber ring (second elastic member). The rubber ring 8 is sandwiched between the outer diameter portion of the adjustment cylinder 2 and the inner diameter portion of the lens hood 6 without a gap. A back cover 29 snaps to the mount 19 to cut off harmful light. Reference numeral 34 denotes a main board (control unit), which is electrically connected to the focus unit 28 and the main diaphragm unit 30 and performs various controls.

  Here, the holding structure of the first group holding frame for the rectilinear cylinder 3 will be described with reference to FIG. 3 to FIG. 7. FIG. 4 is a side view of the rectilinear cylinder 3 and the first group holding frame 10. FIG. 5 is a cross-sectional view of the main part of the first group holding frame 10 (cross-sectional view of the first cam follower). FIG. 6 is a cross-sectional view of the main part of the first group holding frame 10 (cross-sectional view of the second cam follower). FIG. 7 is a detailed view of the second cam follower.

  The roller 10a which is the first cam follower has a structure in which a resin member 10a2 is covered around a metal core member 10a1, and the core member 10a1 and the resin member 10a2 are integrally formed. The roller 10 a is firmly screwed using a screw 10 c, and the resin member 10 a 2 is engaged with the cam groove 3 b of the rectilinear cylinder 3. The diameter of the resin member 10a2 is slightly larger than the width of the cam groove 3b. For this reason, the roller 10a is lightly press-fitted and incorporated into the cam groove 3b. Specifically, the size is set to a size that allows the first group holding frame 10 to be press-fitted so as to be freely rotatable about the optical axis without play during adjustment.

  On the outer periphery of the straight cylinder 3, cam grooves 3 b are provided in six equal parts, and rollers 10 a are incorporated in three of them. Rollers 10d, which are second cam followers made of a metal material, are incorporated in the remaining three locations. The roller 10d is fixed by using a screw 10c similarly to the roller 10a. As shown in FIG. 7, the roller 10d has an oval shape having a flat surface portion 10e in which a cylindrical portion is removed in parallel. The width D1 of the planar portion 10e is designed to be smaller than the width D2 of the cam groove 3b, and is set to a dimension that allows a slight gap even when the component tolerance varies. In such a configuration, when an impact is applied from the outside, the flat portion 10e of the roller 10d contacts the cam groove 3b before the roller 10a is plastically deformed (in the elastic deformation region), thereby preventing the roller 10a from being damaged. Is done.

  In FIG. 4, 16 is a detent. The rotation stopper 16 is fixed to the circumferential groove 3 f of the straight cylinder 3 with a screw 13 a. The cylindrical portion 13 b of the rotation stopper 13 is fitted in the groove 10 f of the first group holding frame 10. At the time of adjustment, the screw 16a is loosened and the first group holding frame 10 is rotated around the optical axis, so that the first group holding frame 10 is rotated in the optical axis direction according to the lift of the cam groove 3b. By tightening the screw 16a after the adjustment, the first group holding frame 10 can be fixed so as not to rotate.

  The lens barrel 1 of this embodiment is a wide-angle zoom lens. For this reason, the outer diameter of the first lens unit L1 is large and its weight is heavy. As the focal length becomes wider, it is necessary to increase the outer diameter of the first lens unit L1 in order to allow light rays having a wider angle of view to enter. Along with this, the weight tends to increase. When the weight of the lens is increased, the impact applied to the roller for moving the lens holding frame (the first group holding frame 10) during the zoom operation increases, and there is a concern about the plastic deformation and cracking of the roller. In the lens barrel 1 of the present embodiment, before the roller 10a (first cam follower) is deformed, the roller 10d (second cam follower) that receives an impact first is separately provided, so the roller 10a is deformed. Hateful. For this reason, according to the lens barrel of the present embodiment, it is possible to realize good optical performance.

(Second Embodiment)
Next, a lens barrel in the second embodiment of the present invention will be described with reference to FIGS. This embodiment is different from the lens barrel in the first embodiment in that the configuration of the second cam follower (roller 10d) is changed. Since the lens barrel of the present embodiment is the same as that of the first embodiment except for the configuration of the second cam follower (roller 10d ′), description other than the configuration of the second cam follower will be omitted.

  FIG. 8 is a detailed view of the second cam follower (roller 10d ') in the present embodiment. FIG. 9 is a detailed view of the first group holding frame 10 in the present embodiment. When the roller 10 d is assembled to the first group holding frame 10, the cylindrical portion 10 h is introduced into the round groove portion 10 j of the first group holding frame 10 and fixed with screws. In the present embodiment, the roller 10d 'is provided with an angle positioning part 10i (positioning part). The angle positioning part 10i is fitted into the groove part 10k of the first group holding frame 10, and the angular position ( Phase).

  According to the present embodiment, when an impact is applied from the outside, the flat portion 10e of the roller 10d 'that is the second cam follower is regulated so as to come into contact with the cam groove 3b of the rectilinear cylinder 3. For this reason, the deformation of the first cam follower with respect to the impact is less likely to occur, and the impact resistance can be further improved.

(Third embodiment)
Next, a lens barrel according to the third embodiment of the present invention will be described with reference to FIGS. This embodiment is different from the lens barrel in the first embodiment in that the configuration of the second cam follower (roller 10d) is changed. Since the lens barrel of the present embodiment is the same as that of the first embodiment except for the configuration of the second cam follower (roller 10g), description other than the configuration of the second cam follower will be omitted.

  FIG. 10 is an exploded perspective view of the main part of the lens barrel in the present embodiment. FIG. 11 is a detailed view of the second cam follower (roller 10g) in the present embodiment. The first cam follower (roller 10a) has a structure in which a metal core member 10a1 is covered with a resin member 10a2, and the core member 10a1 and the resin member 10a2 are integrally formed. The roller 10 a is firmly screwed using a screw 10 c, and the resin member 10 a 2 is engaged with the cam groove 3 b of the rectilinear cylinder 3. The diameter of the resin member 10a2 is slightly larger than the width of the cam groove 3b, and the roller 10a is lightly press-fitted and incorporated into the cam groove 3b. More specifically, the size is set to a size that allows the first group holding frame 10 to be press-fitted so that the first group holding frame 10 can be freely rotated about the optical axis (around the optical axis OA) without rattling.

  On the outer periphery of the straight cylinder 3, cam grooves 3 b are provided in six equal parts, and rollers 10 a are incorporated in three of them. In the remaining three places, rollers 10g (second cam followers) made of a metal material are incorporated. The roller 10g is fixed with screws 10c similarly to the roller 10a. As shown in FIG. 11, the roller 10g has a cylindrical shape (cylindrical portion 10m). The diameter D3 of the cylindrical portion 10m is set smaller than the width D2 of the cam groove 3b, and is set so that a slight gap is formed even when the component tolerance varies. In such a configuration, when an impact is applied from the outside, the roller 10a comes into contact with the cam groove 3b in the elastic deformation region before the roller 10a is plastically deformed, thereby preventing the roller 10a from being damaged.

(Fourth embodiment)
Next, an optical apparatus according to the fourth embodiment will be described with reference to FIG. FIG. 12 is a configuration diagram of an imaging apparatus 200 (single-lens reflex camera) as an optical apparatus in the present embodiment. The imaging device 200 includes the lens barrel 1 in each of the above-described embodiments.

  The lens barrel 1 (interchangeable lens) has an imaging optical system 110 (optical system) including a first lens group L1, a second lens group L2, and a third lens group L3. Reference numeral 220 denotes a camera body (imaging apparatus body). The camera body 220 includes a quick return mirror 203, a focusing screen 204, a penta roof prism 205, an eyepiece lens 206, and the like. The quick return mirror 203 reflects the light beam formed via the imaging optical system 110 upward. The focusing screen 204 is disposed at the image forming position of the imaging optical system 110. The penta roof prism 205 converts the reverse image formed on the focusing screen 204 into an erect image. The user can observe the erect image through the eyepiece lens 206. Reference numeral 207 denotes a photosensitive surface. On the photosensitive surface 207, a photoelectric conversion element (imaging element) such as a CCD sensor or a CMOS sensor that receives an image or a silver salt film is arranged. At the time of shooting, the quick return mirror 203 is retracted from the optical path, and an image (optical image) is formed on the photosensitive surface 207 by the imaging optical system 110. As described above, the image sensor photoelectrically converts the optical image formed by the imaging optical system 110 and outputs image data.

  By applying the lens barrel 1 of the present embodiment to the imaging device 200 such as a single-lens reflex camera, an optical device having high optical performance can be realized. The lens barrel 1 is an interchangeable lens configured to be detachable from the camera body 220. However, the present embodiment can also be applied to an imaging apparatus in which the lens barrel 1 and the camera body 220 are integrally configured. It is. The lens barrel 1 can also be applied to a mirrorless single-lens reflex camera (mirrorless camera) without a quick return mirror.

  The lens barrel of each embodiment includes a lens holding frame (first group holding frame 10) for holding a lens, a rectilinear cylinder 3 that can move linearly while holding the lens holding frame, and a cam groove 3b of the rectilinear cylinder. A first cam follower and a second cam follower are provided. The first cam follower (roller 10a) can adjust the position of the lens holding frame. The second cam followers (rollers 10d, 10d ′, 10g) are configured to abut against the cam grooves (side surfaces thereof) and reduce deformation of the first cam followers when an external force (impact from the outside) is applied. ing.

  Preferably, the first cam follower can adjust the position of the lens holding frame in the optical axis direction by moving along the cam groove of the rectilinear cylinder. Preferably, the width of the first cam follower is larger than the width of the cam groove of the straight cylinder, and the width of the second cam follower (D1, D3) is smaller than the width of the cam groove (D2). More preferably, the first cam follower is press-fitted and engaged with the cam groove of the straight cylinder. More preferably, the first cam follower uses a screw to fix the lens holding frame and the rectilinear cylinder.

  Preferably, the gap between the second cam follower and the cam groove of the straight cylinder is larger than the gap between the cam groove and the first cam follower. Preferably, the first cam follower is made of a resin material, and the second cam follower is made of a metal material. More preferably, the first cam follower is formed of a metal member (metal core member 10a1) and a resin material (resin member 10a2) covering the periphery of the metal member. More preferably, when an external force is applied, the second cam follower comes into contact with the cam groove of the straight cylinder before the first cam follower is plastically deformed (during elastic deformation). Preferably, the side surface of the first cam follower has a circular shape, and the side surface of the second cam follower includes a flat shape (planar portion 10e). Preferably, the second cam follower has a positioning unit (angle positioning unit 10i) that determines a phase (an incorporated phase) with respect to the lens holding frame.

  According to the lens barrel of each embodiment, in a configuration having an optical adjustment mechanism that uses a roller to perform position adjustment or tilt adjustment in the optical axis direction, even when an impact is applied from the outside, deformation due to roller dents Can be reduced. For this reason, according to each embodiment, it is possible to provide a lens barrel, an optical apparatus, and an imaging apparatus that have high impact resistance and improved optical performance.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

  Although the lens barrel of each embodiment has been described as a lens barrel used in an imaging apparatus, the present invention is not limited to this. Each embodiment can also be applied to a lens barrel used in an optical apparatus other than the imaging apparatus, such as a projection lens of a projector and an optical system of a copying machine.

1 lens barrel 3 rectilinear barrel 10 first group holding frame (lens holding frame)
10a Roller (first cam follower)
10d, 10g roller (second cam follower)

Claims (13)

A lens holding frame for holding the lens;
A rectilinear cylinder capable of moving straight while holding the lens holding frame;
A first cam follower and a second cam follower provided in the cam groove of the straight cylinder,
The first cam follower can adjust the position of the lens holding frame;
The lens barrel, wherein the second cam follower is configured to abut against the cam groove when an external force is applied to reduce deformation of the first cam follower.   2. The lens according to claim 1, wherein the first cam follower can adjust the position of the lens holding frame in the optical axis direction by moving along the cam groove of the rectilinear cylinder. A lens barrel. The width of the first cam follower is larger than the width of the cam groove of the rectilinear cylinder,
The lens barrel according to claim 1 or 2, wherein a width of the second cam follower is smaller than a width of the cam groove.   The lens barrel according to claim 3, wherein the first cam follower is press-fitted and engaged with the cam groove of the rectilinear cylinder.   The lens barrel according to claim 4, wherein the first cam follower fixes the lens holding frame and the rectilinear barrel using screws.   6. The first gap between the second cam follower and the cam groove of the rectilinear cylinder is larger than the second gap between the cam groove and the first cam follower. The lens barrel according to any one of the above. The first cam follower is made of a resin material,
The lens barrel according to any one of claims 1 to 6, wherein the second cam follower is made of a metal material.   The lens barrel according to claim 7, wherein the first cam follower is formed of a metal member and the resin material covering the periphery of the metal member.   The said 2nd cam follower contact | abuts to the said cam groove of the said rectilinear advance cylinder before the said 1st cam follower deforms plastically when the said external force is added. Lens barrel. The side surface of the first cam follower is circular,
The lens barrel according to any one of claims 1 to 9, wherein a side surface of the second cam follower includes a flat shape.   The lens barrel according to claim 1, wherein the second cam follower includes a positioning unit that determines a phase with respect to the lens holding frame.   An optical apparatus comprising the lens barrel according to any one of claims 1 to 11. The lens barrel according to any one of claims 1 to 11,
An image pickup device comprising: an image pickup device that photoelectrically converts an optical image formed through an optical system of the lens barrel and outputs image data.