JP7655540B2 - Lens barrel - Google Patents

Description

The present invention relates to a lens barrel that is attached to a camera body for use.

Conventionally, lens barrels that are attached to a camera body for use are known (see, for example, Patent Document 1). Inside the lens barrel described in Patent Document 1, a focus mechanism including a focus lens group and a zoom mechanism including a zoom lens group are arranged. Also, inside this lens barrel, a master lens group is arranged. The master lens group includes an extender group for switching the shooting magnification. The extender group includes a front lens group and a rear lens group. The front lens group is supported by the front lens frame. The rear lens group is supported by the rear lens frame.

In the lens barrel described in Patent Document 1, a threaded portion is formed on the inner circumference side of the front lens frame. A threaded portion that screws into the threaded portion of the front lens frame and an adjustment gear are formed on the outer circumference of the rear lens frame. In this lens barrel, it is possible to adjust the position of the rear lens group in the optical axis direction relative to the front lens group by turning the adjustment gear to change the amount of screwing between the threaded portion of the front lens frame and the threaded portion of the rear lens frame. In addition, it is possible to adjust the optical performance (optical characteristics) of the extender group by adjusting the position of the rear lens group in the optical axis direction relative to the front lens group.

In addition, in the lens barrel described in Patent Document 1, an opening is formed in the connecting ring that is disposed on the outer periphery of the extender group, and a tool can be inserted through the opening of the connecting ring to engage with the adjustment gear of the rear lens frame. That is, in this lens barrel, the adjustment gear is turned with a tool inserted through the opening of the connecting ring to change the amount of engagement between the threaded portion of the front lens frame and the threaded portion of the rear lens frame. Therefore, in this lens barrel, it is possible to adjust the optical performance of the extender group with the extender group disposed inside the lens barrel.

Patent No. 5479650

The inventors of the present application are considering miniaturizing the zoom mechanism disposed inside the lens barrel, and in order to miniaturize the zoom mechanism, are considering including a lens with a high effect in the zoom lens group. The inventors of the present application are also considering ensuring the optical performance of the zoom lens group, for example, by adjusting the position of this lens with a high effect in the optical axis direction. However, the inventors' studies have revealed that even if the position of the lens with a high effect in the optical axis direction is adjusted, it may be difficult to ensure the optical performance of the zoom lens group.

The object of the present invention is to provide a lens barrel that can ensure the optical performance of a lens group that includes a lens with a high degree of effectiveness, even if that lens group includes such a lens.

In order to solve the above problems, the lens barrel of the present invention includes a first lens frame that holds a lens on its inner periphery, a second lens frame that holds a lens on its inner periphery, a first adjustment mechanism for adjusting the position of the second lens frame in the optical axis direction relative to the first lens frame by moving the second lens frame relative to the first lens frame in the optical axis direction of a lens held in the second lens frame, and a second adjustment mechanism for adjusting the radial position of the second lens frame relative to the first lens frame by moving the second lens frame in a radial direction perpendicular to the optical axis direction relative to the first lens frame, and the first adjustment mechanism is disposed on the outer periphery of the first lens frame. The optical system includes a rotating frame that is rotatably held by the first lens frame with the optical axis direction as the axis of rotation, and that moves in the optical axis direction relative to the first lens frame when rotated with the optical axis direction as the axis of rotation, and a first biasing member that biases the second lens frame to one side in the optical axis direction relative to the first lens frame, and the one side in the optical axis direction, which is the biasing direction of the second lens frame by the first biasing member, is defined as a first direction side, and the opposite side to the first direction side is defined as a second direction side, the rotating frame is disposed on the first direction side of the second lens frame, the first biasing member biases the second lens frame towards the rotating frame, and the second lens frame is configured such that the rotating frame biases the first lens frame the second adjustment mechanism includes a plurality of adjustment screws arranged circumferentially around the first lens frame and contacting the second lens frame from the radially outer side, the first lens frame is formed with a plurality of screw holes into which the adjustment screws engage, the position of the second lens frame in the optical axis direction relative to the first lens frame is adjusted by the rotating frame, and the radial position of the second lens frame in the radial direction relative to the first lens frame is adjusted by the adjustment screws, and the first lens frame includes a main lens frame which holds a lens on its inner peripheral side, and a main lens frame which is fixed to the main lens frame and is movable relative to the rotating frame. and an adjustment frame arranged on the second direction side of the rotating frame, the main lens frame having a cylindrical main lens frame tube portion arranged on the inner peripheral side of the second lens frame, and the adjustment frame having a cylindrical first adjustment frame tube portion arranged on the outer peripheral side of the second lens frame and having a screw hole formed therein, a cylindrical second adjustment frame tube portion arranged on the inner peripheral side of the second lens frame and fixed to the main lens frame tube portion, and a circular, flat adjustment frame annular portion connecting the first direction side end of the first adjustment frame tube portion and the first direction side end of the second adjustment frame tube portion and arranged between the rotating frame and the second lens frame in the optical axis direction .

The lens barrel of the present invention includes a first adjustment mechanism for adjusting the position of the second lens frame in the optical axis direction relative to the first lens frame by moving the second lens frame in the optical axis direction relative to the first lens frame, and a second adjustment mechanism for adjusting the radial position of the second lens frame in the optical axis direction relative to the first lens frame by moving the second lens frame in a radial direction perpendicular to the optical axis direction relative to the first lens frame, and the optical axis direction and radial position of the lens held in the second lens frame are adjustable. Therefore, according to the study of the present inventor, in the present invention, even if the lens group held in the first lens frame and the second lens frame includes a lens with a large effect, by holding the lens with a large effect in the second lens frame, it is possible to ensure the optical performance of the lens group including the lens with a large effect.

In addition, in the present invention, the position of the second lens frame in the optical axis direction relative to the first lens frame is adjusted by a rotating frame that is rotatably held on the outer periphery of the first lens frame, and the radial position of the second lens frame in the first lens frame is adjusted by an adjustment screw that engages with a screw hole in the first lens frame, so that the optical axis position and radial position of the second lens frame can be adjusted independently. Therefore, in the present invention, it is possible to easily adjust the position of the second lens frame.

In the present invention, it is preferable that the first adjustment mechanism is disposed between the rotating frame and the second lens frame in the optical axis direction and includes a plurality of balls arranged in the circumferential direction. With this configuration, it is possible to reduce the sliding resistance of the rotating frame relative to the second lens frame when the rotating frame rotates. Therefore, it is possible to smoothly rotate the rotating frame relative to the first lens frame.

In the present invention, it is preferable that the main lens frame includes a flat, annular main lens frame annular portion that is connected to the first direction end of the main lens frame cylindrical portion and is disposed on the first direction side of the rotating frame, and the first adjustment mechanism includes a second biasing member that is disposed between the rotating frame and the adjustment frame in the optical axis direction and biases the rotating frame toward the main lens frame annular portion. With this configuration, it is possible to effectively suppress rattling of the rotating frame relative to the first lens frame in the optical axis direction.

In the present invention, the lens barrel preferably includes a fixing screw for fixing the rotating frame to the first lens frame. With this configuration, it is possible to reliably fix the rotating frame so that it does not rotate after adjusting the position of the second lens frame in the optical axis direction.

In the present invention, for example, the first lens frame and the rotating frame are helicoidally engaged. In this case, with a relatively simple configuration, when the rotating frame is rotated relative to the first lens frame, it is possible to move the rotating frame in the optical axis direction relative to the first lens frame.

In the present invention, for example, a V-groove in which the tip of the adjustment screw is placed is formed on the outer peripheral surface of the second lens frame, and the tip of the adjustment screw is in contact with the side of the V-groove. In this case, it becomes possible to restrict the movement of the second lens frame in the optical axis direction by the adjustment screw.

In order to solve the above-mentioned problems, the lens barrel of the present invention includes a first lens frame that holds a lens on its inner periphery, a second lens frame that holds a lens on its inner periphery, a first adjustment mechanism for adjusting the position of the second lens frame in the optical axis direction relative to the first lens frame by moving the second lens frame relative to the first lens frame in the optical axis direction of the lens held in the second lens frame, a second adjustment mechanism for adjusting the radial position of the second lens frame relative to the first lens frame by moving the second lens frame in a radial direction perpendicular to the optical axis direction relative to the first lens frame, and a rectilinear cylinder and a cam cylinder that are disposed on the outer periphery sides of the first lens frame and the second lens frame, and the first adjustment mechanism adjusts the position of the first lens frame in the optical axis direction relative to the first lens frame. the first lens frame is arranged on the outer periphery of the lens frame, is rotatably held by the first lens frame with the optical axis direction as the axis of rotation, and moves in the optical axis direction relative to the first lens frame when rotated with the optical axis direction as the axis of rotation, and a first biasing member biases the second lens frame to one side in the optical axis direction relative to the first lens frame, and the one side in the optical axis direction which is the biasing direction of the second lens frame by the first biasing member is defined as a first direction side, and the opposite side to the first direction side is defined as a second direction side, the rotating frame is arranged on the first direction side of the second lens frame, the first biasing member biases the second lens frame towards the rotating frame, and the second lens frame moves in the optical axis direction when the rotating frame rotates relative to the first lens frame the first lens frame is moved in the optical axis direction relative to the first lens frame, the second adjustment mechanism includes a plurality of adjustment screws arranged in the circumferential direction of the first lens frame and contacting the second lens frame from the outside in the radial direction, the first lens frame is formed with a plurality of screw holes into which the adjustment screws engage, the position of the second lens frame in the optical axis direction relative to the first lens frame is adjusted by the rotating frame, and the radial position of the second lens frame in the radial direction relative to the first lens frame is adjusted by the adjustment screws, the linear cylinder is formed with a linear groove having the optical axis direction as its longitudinal direction, the cam cylinder is formed with a cam groove, the first lens frame is fitted with a cam follower that engages with the linear groove and the cam groove , and the outer peripheral surface of the rotating frame is fitted with a plurality of screw holes into which the adjustment screws engage. a gear portion consisting of a number of teeth is formed, the gear portion overlaps with at least one of the straight-advance tube and the cam tube in the radial direction, the adjustment screw overlaps with at least one of the straight-advance tube and the cam tube in the radial direction, at least one of the straight-advance tube and the cam tube that overlaps with the gear portion in the radial direction has a first through hole formed therethrough in the radial direction, allowing a portion of a tool for turning the gear portion to pass through, and at least one of the straight-advance tube and the cam tube that overlaps with the adjustment screw in the radial direction has a second through hole formed therethrough in the radial direction, allowing a portion of a tool for turning the adjustment screw to pass through.
The lens barrel of the present invention includes a first adjustment mechanism for adjusting the position of the second lens frame in the optical axis direction relative to the first lens frame by moving the second lens frame in the optical axis direction of the lens relative to the first lens frame, and a second adjustment mechanism for adjusting the radial position of the second lens frame in the optical axis direction relative to the first lens frame by moving the second lens frame in the radial direction perpendicular to the optical axis direction relative to the first lens frame, and the optical axis direction and radial position of the lens held in the second lens frame are adjustable. Therefore, according to the study of the present inventor, in the present invention, even if a lens with a large effect is included in the lens group held in the first lens frame and the second lens frame, it is possible to ensure the optical performance of the lens group including the lens with a large effect by holding the lens with a large effect in the second lens frame.
In addition, in the present invention, the position of the second lens frame in the optical axis direction relative to the first lens frame is adjusted by a rotating frame that is rotatably held by the first lens frame on the outer periphery side of the first lens frame, and the position of the second lens frame in the radial direction relative to the first lens frame is adjusted by an adjustment screw that engages with a screw hole in the first lens frame, so that the position of the second lens frame in the optical axis direction and the position in the radial direction can be adjusted independently. Therefore, in the present invention, it is possible to easily adjust the position of the second lens frame.

In addition, in the present invention, a gear portion composed of a plurality of teeth is formed on the outer peripheral surface of the rotating frame, the gear portion overlaps with at least one of the straight-line cylinder and the cam cylinder in the radial direction, the adjustment screw overlaps with at least one of the straight-line cylinder and the cam cylinder in the radial direction, at least one of the straight-line cylinder and the cam cylinder that overlaps with the gear portion in the radial direction is formed with a first through hole passing therethrough in the radial direction, allowing a portion of a jig for turning the gear portion to pass through, and at least one of the straight-line cylinder and the cam barrel that overlaps with the adjustment screw in the radial direction is formed with a second through hole passing therethrough in the radial direction, allowing a portion of a tool for turning the adjustment screw to pass through.

Therefore , even if a linear motion cylinder or a cam cylinder is arranged on the outer periphery of the first lens frame and the second lens frame, it is possible to rotate the rotating frame by turning the gear part with a jig and to turn the adjustment screw with a tool in an assembled state of the lens barrel. Therefore, even if a linear motion cylinder or a cam cylinder is arranged on the outer periphery of the first lens frame and the second lens frame, it is possible to adjust the optical axis position and radial position of the second lens frame relative to the first lens frame without disassembling the lens barrel, and as a result, it is possible to easily adjust the optical axis position and radial position of the second lens frame relative to the first lens frame.

Furthermore, in order to solve the above-mentioned problems, the lens barrel of the present invention includes a first lens frame that holds a lens on its inner periphery, a second lens frame that holds a lens on its inner periphery, a first adjustment mechanism for adjusting a position of the second lens frame in the optical axis direction relative to the first lens frame by moving the second lens frame relative to the first lens frame in the optical axis direction of a lens held in the second lens frame, a second adjustment mechanism for adjusting a radial position of the second lens frame relative to the first lens frame by moving the second lens frame in a radial direction perpendicular to the optical axis direction relative to the first lens frame, and a cylindrical first barrel member, wherein the first adjustment mechanism includes a rotating frame that is disposed on the outer periphery of the first lens frame and is rotatably held by the first lens frame with the optical axis direction as the axis of rotation, and moves in the optical axis direction relative to the first lens frame when rotated with the optical axis direction as the axis of rotation, and a first biasing member that biases the second lens frame toward one side in the optical axis direction relative to the first lens frame, and the one side in the optical axis direction, which is the biasing direction of the second lens frame by the first biasing member, is set to a first direction. The rotating frame is disposed on the first direction side of the second lens frame, the first biasing member biases the second lens frame towards the rotating frame, and the second lens frame moves in the optical axis direction relative to the first lens frame when the rotating frame rotates relative to the first lens frame and moves in the optical axis direction, the second adjustment mechanism includes a plurality of adjustment screws that are arranged in the circumferential direction of the first lens frame and contact the second lens frame from the outside in the radial direction, and the first lens frame has a plurality of screws with which the adjustment screws engage. a hole is formed, the position of the second lens frame in the optical axis direction relative to the first lens frame is adjusted by the rotating frame, the radial position of the second lens frame relative to the first lens frame is adjusted by an adjustment screw, the first cylindrical member is arranged on the outer periphery of the rotating frame, a gear portion composed of a plurality of teeth is formed on the outer periphery of the rotating frame, a first through hole is formed in the first cylindrical member to allow a part of a jig for rotating the gear portion to pass through, and the first through hole penetrates the first cylindrical member in the radial direction.
The lens barrel of the present invention includes a first adjustment mechanism for adjusting the position of the second lens frame in the optical axis direction relative to the first lens frame by moving the second lens frame in the optical axis direction of the lens relative to the first lens frame, and a second adjustment mechanism for adjusting the radial position of the second lens frame in the optical axis direction relative to the first lens frame by moving the second lens frame in the radial direction perpendicular to the optical axis direction relative to the first lens frame, and the optical axis direction and radial position of the lens held in the second lens frame are adjustable. Therefore, according to the study of the present inventor, in the present invention, even if a lens with a large effect is included in the lens group held in the first lens frame and the second lens frame, it is possible to ensure the optical performance of the lens group including the lens with a large effect by holding the lens with a large effect in the second lens frame.
In addition, in the present invention, the position of the second lens frame in the optical axis direction relative to the first lens frame is adjusted by a rotating frame that is rotatably held by the first lens frame on the outer periphery side of the first lens frame, and the position of the second lens frame in the radial direction relative to the first lens frame is adjusted by an adjustment screw that engages with a screw hole in the first lens frame, so that the position of the second lens frame in the optical axis direction and the position in the radial direction can be adjusted independently. Therefore, in the present invention, it is possible to easily adjust the position of the second lens frame.
In addition, in the present invention, the lens barrel includes a cylindrical first barrel member disposed on the outer periphery of the rotating frame, a gear portion formed of a plurality of teeth is formed on the outer periphery of the rotating frame, and a first through hole is formed in the first barrel member through which a part of a jig for rotating the gear portion passes, and the first through hole penetrates the first barrel member in the radial direction . Therefore , even if the first barrel member is disposed on the outer periphery of the rotating frame, it is possible to rotate the rotating frame by rotating the gear portion with the jig in an assembled state of the lens barrel. Therefore, even if the first barrel member is disposed on the outer periphery of the rotating frame, it is possible to adjust the position of the second lens frame in the optical axis direction relative to the first lens frame without disassembling the lens barrel, and as a result, it is possible to easily adjust the position of the second lens frame in the optical axis direction relative to the first lens frame.

In addition, in order to solve the above-mentioned problems, the lens barrel of the present invention includes a first lens frame that holds a lens on its inner periphery side, a second lens frame that holds a lens on its inner periphery side, a first adjustment mechanism for adjusting a position of the second lens frame in the optical axis direction relative to the first lens frame by moving the second lens frame relative to the first lens frame in the optical axis direction of a lens held in the second lens frame, a second adjustment mechanism for adjusting a radial position of the second lens frame relative to the first lens frame by moving the second lens frame in a radial direction perpendicular to the optical axis direction relative to the first lens frame, and a cylindrical second barrel member, and the first adjustment mechanism includes a rotating frame that is disposed on the outer periphery side of the first lens frame and is rotatably held by the first lens frame with the optical axis direction as the axis of rotation, and moves in the optical axis direction relative to the first lens frame when rotated with the optical axis direction as the axis of rotation, and a first biasing member that biases the second lens frame to one side in the optical axis direction relative to the first lens frame, and the optical axis is a biasing direction of the second lens frame by the first biasing member. the first lens frame has a first biasing member biasing the second lens frame toward the first lens frame, and the second lens frame moves in the optical axis direction relative to the first lens frame when the rotating frame rotates relative to the first lens frame and moves in the optical axis direction; the second adjustment mechanism includes a plurality of adjustment screws arranged circumferentially around the first lens frame and contacting the second lens frame from the outside in the radial direction, the first lens frame has a plurality of screw holes with which the adjustment screws engage, the position of the second lens frame in the optical axis direction relative to the first lens frame is adjusted by the rotating frame, and the radial position of the second lens frame relative to the first lens frame is adjusted by the adjustment screws; the second cylindrical member is arranged outside the adjustment screws in the radial direction, and the second cylindrical member has a second through hole formed therein through which a portion of a tool for turning the adjustment screw passes, and the second through hole penetrates the second cylindrical member in the radial direction.
The lens barrel of the present invention includes a first adjustment mechanism for adjusting the position of the second lens frame in the optical axis direction relative to the first lens frame by moving the second lens frame in the optical axis direction of the lens relative to the first lens frame, and a second adjustment mechanism for adjusting the radial position of the second lens frame in the optical axis direction relative to the first lens frame by moving the second lens frame in the radial direction perpendicular to the optical axis direction relative to the first lens frame, and the optical axis direction and radial position of the lens held in the second lens frame are adjustable. Therefore, according to the study of the present inventor, in the present invention, even if a lens with a large effect is included in the lens group held in the first lens frame and the second lens frame, it is possible to ensure the optical performance of the lens group including the lens with a large effect by holding the lens with a large effect in the second lens frame.
In addition, in the present invention, the position of the second lens frame in the optical axis direction relative to the first lens frame is adjusted by a rotating frame that is rotatably held by the first lens frame on the outer periphery side of the first lens frame, and the position of the second lens frame in the radial direction relative to the first lens frame is adjusted by an adjustment screw that engages with a screw hole in the first lens frame, so that the position of the second lens frame in the optical axis direction and the position in the radial direction can be adjusted independently. Therefore, in the present invention, it is possible to easily adjust the position of the second lens frame.
In addition, in the present invention, the lens barrel includes a cylindrical second barrel member disposed outside the adjustment screw in the radial direction, and the second barrel member is formed with a second through hole through which a part of a tool for turning the adjustment screw passes, and the second through hole penetrates the second barrel member in the radial direction . Therefore , even if the second barrel member is disposed outside the adjustment screw in the radial direction, it is possible to turn the adjustment screw with a tool in the assembled state of the lens barrel. Therefore, even if the second barrel member is disposed outside the adjustment screw in the radial direction, it is possible to adjust the radial position of the second lens frame relative to the first lens frame without disassembling the lens barrel, and as a result, it is possible to easily adjust the radial position of the second lens frame relative to the first lens frame.

As described above, with the lens barrel of the present invention, even if a lens with a high effect is included in the lens group, it is possible to ensure the optical performance of the lens group including the lens with a high effect.

1 is a cross-sectional view illustrating a configuration of a lens barrel according to an embodiment of the present invention. 2 is a perspective cross-sectional view of a portion of the lens barrel shown in FIG. 1 . FIG. 2 is an enlarged view of part E in FIG.

The following describes an embodiment of the present invention with reference to the drawings.

(Overall configuration of lens barrel)
FIG. 1 is a cross-sectional view for explaining the configuration of a lens barrel 1 according to an embodiment of the present invention.

The lens barrel 1 of this embodiment is attached to a camera body (not shown) for use. The camera body is equipped with an imaging element such as a C-MOS image sensor. The lens barrel 1 is formed in a generally cylindrical shape. The lens barrel 1 is equipped with lenses 2 to 4 arranged inside the lens barrel 1, a lens frame 5 that holds the lens 2 on the inner circumference side, a lens frame 6 that holds the lens 3 on the inner circumference side, a lens frame 7 that holds the lens 4 on the inner circumference side, and a cylindrical fixed cylinder 8 that is fixed to the camera body. The lens frame 5 of this embodiment is a first lens frame, and the lens frame 6 is a second lens frame. Note that only a portion of the fixed cylinder 8 is shown in FIG. 1.

Lenses 2 to 4 are arranged in this order in the direction of the optical axis L of lenses 2 to 4 (optical axis direction). Specifically, if the side of the optical axis direction that is attached to the camera body (the Z2 direction side in FIG. 1, etc., the image formation side) is the rear side, and the Z1 direction side (the subject side) in FIG. 1, etc., which is the opposite side to the rear side, is the front side, lenses 2 to 4 are arranged in this order from the front side to the rear side. In the following explanation, the direction perpendicular to the optical axis direction (front-back direction) (direction perpendicular to the optical axis) is referred to as the "radial direction". Note that in this specification, "lens" includes not only a single lens, but also a lens group consisting of multiple lenses. Lens 2 in this embodiment is a lens group consisting of multiple lenses. On the other hand, lenses 3 and 4 are single lenses.

Lens 4 is a fixed lens that does not move in the front-rear direction relative to fixed cylinder 8. Lens frame 7 is fixed to fixed cylinder 8. Lenses 2 and 3 are zoom lenses that can move in the front-rear direction relative to fixed cylinder 8, and lenses 2 and 3 form part of a zoom lens group. Lens frames 5 and 6 can move in the front-rear direction (optical axis direction) relative to fixed cylinder 8. Lenses 2 and 3 and lens frames 5 and 6 arranged at the wide-angle end are shown above optical axis L in Figure 1, and lenses 2 and 3 and lens frames 5 and 6 arranged at the telephoto end are shown below optical axis L in Figure 1. Lens 3 in this embodiment is a lens with a large effect.

The lens barrel 1 includes a linear cylinder 11 and a cam cylinder 12 for moving the lens frames 5 and 6 in the front-rear direction relative to the fixed cylinder 8. In this embodiment, the zoom mechanism is composed of the lenses 2 and 3, the lens frames 5 and 6, the linear cylinder 11, and the cam cylinder 12. The lens barrel 1 also includes a first adjustment mechanism 14 for adjusting (specifically, fine-tuning) the front-rear position of the lens frame 6 relative to the lens frame 5 by moving the lens frame 6 in the front-rear direction (optical axis direction) relative to the lens frame 5 during the manufacture of the lens barrel 1, and a second adjustment mechanism 15 for adjusting (specifically, fine-tuning) the radial position of the lens frame 6 relative to the lens frame 5 by moving the lens frame 6 in the radial direction relative to the lens frame 5. That is, the lens 3 in this embodiment is an adjustable lens whose front-rear and radial positions are finely adjusted relative to the lens 2.

The lens frame 5 is generally formed in a stepped, approximately cylindrical shape. The lens frame 6 is generally formed in a stepped, approximately cylindrical shape. The lens frame 6 is movable in the front-rear direction together with the lens frame 5 relative to the fixed cylinder 8. The specific configuration of the lens frames 5, 6 will be described later. The lens frame 7 is generally cylindrical. The lens frames 5-7 are arranged so that the axes of the lens frames 5-7 coincide with the optical axis L. In the following description, the circumferential direction of the lens frames 5-7 (the circumferential direction centered on the optical axis L) is referred to as the "circumferential direction".

The lens frame 7 is disposed on the inner periphery of the fixed tube 8. The lens 4 is attached to the rear end of the lens frame 7. A through hole 7a is formed at the front end of the lens frame 7, penetrating the lens frame 7 in the radial direction. The through hole 7a is a round hole. The through holes 7a are formed in four places at a 90° pitch around the optical axis L. The fixed tube 8 is formed with a through hole 8a that penetrates the fixed tube 8 in the radial direction. The through hole 8a is, for example, a round hole of the same shape as the through hole 7a. The through holes 8a are formed in four places at a 90° pitch around the optical axis L. The through hole 8a is formed at the same position as the through hole 7a in the front-rear direction and the circumferential direction, and overlaps with the through hole 7a in the radial direction.

The linear barrel 11 and the cam barrel 12 are formed in a cylindrical shape. The linear barrel 11 and the cam barrel 12 are disposed on the outer periphery side of the lens frames 5, 6, the first adjustment mechanism 14, and the second adjustment mechanism 15. The linear barrel 11 is disposed on the inner periphery side of the cam barrel 12. The rear end of the linear barrel 11 is fixed to the fixed barrel 8. A linear groove 11a is formed in the linear barrel 11, with the longitudinal direction being the front-to-rear direction. The linear groove 11a penetrates the linear barrel 11 in the radial direction.

The cam barrel 12 is rotatable relative to the linear barrel 11 with the forward and backward directions as the axial direction of rotation. A cam groove 12a is formed on the inner peripheral surface of the cam barrel 12. The cam groove 12a is formed, for example, in a spiral shape. The cam groove 12a is a bottomed groove portion formed on the inner peripheral surface of the cam barrel 12. A cam follower 30 (described below) attached to the lens frame 5 engages with the linear groove 11a and the cam groove 12a. When the cam barrel 12 is rotated relative to the fixed barrel 8, the lens frames 5 and 6 move in the forward and backward directions.

The linear cylinder 11 has through holes 11b to 11d that penetrate the linear cylinder 11 in the radial direction. Through holes 11b and 11d are round holes. Through hole 11c is a rectangular hole with the circumferential direction as the long side direction. Through hole 11b is formed behind through hole 11c, and through hole 11c is formed behind through hole 11d. Through hole 11b is formed in four places at a 90° pitch centered on the optical axis L. Through hole 11c is formed in one place. Through hole 11d is formed in three places at a 120° pitch centered on the optical axis L. Through holes 11b to 11d are formed in positions that do not overlap with linear groove 11a.

The cam barrel 12 has through holes 12b to 12d formed therein, which penetrate the cam barrel 12 in the radial direction. The through hole 12b is, for example, a round hole having the same shape as the through hole 11b, and the through hole 12d is, for example, a round hole having the same shape as the through hole 11d. The through hole 12c is, for example, a square hole having approximately the same shape as the through hole 11c. The through hole 12b is formed rearward of the through hole 12c, and the through hole 12c is formed rearward of the through hole 12d. The through hole 12b is formed in four places at a 90° pitch centered on the optical axis L. The through hole 12c is formed in one place. The through hole 12d is formed in three places at a 120° pitch centered on the optical axis L. The through holes 12b to 12d are formed in positions that do not overlap with the cam groove 12a.

Through holes 11b and 12b are formed at the same position in the front-rear direction. Furthermore, when lenses 2 and 3 are arranged at the telephoto end, through holes 11b and 12b are arranged at the same position in the circumferential direction and overlap in the radial direction. Through holes 11c and 12c are formed at the same position in the front-rear direction. Furthermore, when lenses 2 and 3 are arranged at the telephoto end, through holes 11c and 12c are arranged at the same position in the circumferential direction and overlap in the radial direction. Through holes 11d and 12d are formed at the same position in the front-rear direction. Furthermore, when lenses 2 and 3 are arranged at the telephoto end, through holes 11d and 12d are arranged at the same position in the circumferential direction and overlap in the radial direction.

(Configuration of Lens Frame, First Adjustment Mechanism, and Second Adjustment Mechanism)
Fig. 2 is a perspective cross-sectional view of a portion of the lens barrel 1 shown in Fig. 1. Fig. 3 is an enlarged view of a portion E in Fig. 1.

The first adjustment mechanism 14 moves in the optical axis direction (front-to-back direction) together with the lens frames 5 and 6 between the wide-angle end and the telephoto end. The first adjustment mechanism 14 includes a rotating frame 18 that is rotatably held by the lens frame 5 with the optical axis direction (front-to-back direction) as the axis of rotation, and moves in the optical axis direction (front-to-back direction) relative to the lens frame 5 when rotated with the optical axis direction (front-to-back direction) as the axis of rotation, and a compression coil spring 19 as a first biasing member that biases the lens frame 6 to one side in the optical axis direction (front-to-back direction) relative to the lens frame 5.

The rotating frame 18 is disposed on the outer periphery of the lens frame 5. The rotating frame 18 is disposed in front of the lens frame 6, and the compression coil spring 19 urges the lens frame 6 towards the rotating frame 18. That is, the compression coil spring 19 urges the lens frame 6 forward relative to the lens frame 5. The front side (Z1 direction side) of this embodiment is the first direction side, which is the urging direction of the lens frame 6 by the compression coil spring 19, and the rear side (Z2 direction side) is the second direction side, which is the opposite side to the first direction side.

The first adjustment mechanism 14 also includes a plurality of balls 20 arranged circumferentially and disposed between the rotating frame 18 and the lens frame 6 in the optical axis direction (front-rear direction), and a compression coil spring 21 as a second biasing member that biases the rotating frame 18 forward relative to the lens frame 5. In this embodiment, eight balls 20 are arranged at a 45° pitch centered on the optical axis L. The balls 20 are arranged in ball arrangement holes 26e (described below) formed in the lens frame 5.

The second adjustment mechanism 15 moves in the optical axis direction (front-rear direction) between the wide-angle end and the telephoto end together with the lens frames 5 and 6. The second adjustment mechanism 15 has a plurality of adjustment screws 22 arranged in the circumferential direction and contacting the lens frame 6 from the outside in the radial direction. The adjustment screws 22 are arranged in four locations at 90° pitches centered on the optical axis L. In this embodiment, the adjustment screws 22 are hexagonal socket set screws. The tip of the adjustment screw 22 is formed in a cone shape. In other words, the tip of the adjustment screw 22 is sharp. The adjustment screw 22 engages with a screw hole 26d (described later) formed in the lens frame 5.

The rotating frame 18 is formed in a generally cylindrical shape with a flange that is short in the front-rear direction. A female helicoid screw is formed on the inner peripheral surface of the rotating frame 18. The rotating frame 18 has a circular, flat flange portion 18a that spreads radially outward from the front end of the rotating frame 18 in a flange-like shape, and a cylindrical fixed portion 18b that protrudes forward from the front surface of the flange portion 18a. A gear portion 18c composed of multiple teeth is formed on the outer peripheral surface of the rotating frame 18. Specifically, the gear portion 18c is formed on the outer peripheral surface of the flange portion 18a, and the flange portion 18a is a gear. The axis of the fixed portion 18b coincides with the optical axis L. The fixed portion 18b protrudes forward from the front surface of the flange portion 18a radially outward from the center of the flange portion 18a in the radial direction. Note that the multiple teeth that constitute the gear portion 18c are omitted from the illustration in FIG. 2.

The fixed portion 18b is fixed to the lens frame 5 by the fixing screw 23. That is, the lens barrel 1 is provided with the fixing screw 23 for fixing the rotating frame 18 to the lens frame 5. The fixing screws 23 are arranged in three locations at a pitch of 120° centered on the optical axis L. In this embodiment, the fixing screw 23 is a hexagonal socket set screw. The outer peripheral surface of the tip of the fixing screw 23 is formed into a truncated cone surface, and the tip of the fixing screw 23 is recessed. The fixing screw 23 engages with a screw hole 27a (described later) formed in the lens frame 5.

The rotating frame 18 is disposed radially inward of the linear barrel 11 and the cam barrel 12. In this embodiment, when the lenses 2 and 3 are disposed at the telephoto end, the entire rotating frame 18 is disposed on the inner periphery side of the linear barrel 11 and the cam barrel 12, and the gear portion 18c overlaps with the linear barrel 11 and the cam barrel 12 in the radial direction. On the other hand, when the lenses 2 and 3 are disposed at the wide-angle end, only the fixed portion 18b of the rotating frame 18 is disposed on the inner periphery side of the linear barrel 11. Also, when the lenses 2 and 3 are disposed at the wide-angle end, the gear portion 18c is disposed radially on the inner periphery side of the front end of the fixed barrel 8, and overlaps with the front end of the fixed barrel 8 in the radial direction.

The lens frame 5 includes a main lens frame 25 that holds the lens 2 on the inner circumference side, an adjustment frame 26 that is fixed to the main lens frame 25 and is positioned behind the rotating frame 18, a fixed frame 27 that is fixed to the main lens frame 25, and a fixed frame 28 that is fixed to the adjustment frame 26. The lens frame 5 in this embodiment is composed of the main lens frame 25, the adjustment frame 26, and the fixed frames 27, 28. The main lens frame 25, the adjustment frame 26, and the fixed frame 27 are formed in a stepped, approximately cylindrical shape. The fixed frame 28 is formed in a cylindrical shape that is short in the front-to-rear direction. The axis of the main lens frame 25, the axis of the adjustment frame 26, and the axis of the fixed frames 27, 28 are approximately aligned with the optical axis L.

The main lens frame 25 includes a tube portion 25a serving as a cylindrical main lens frame tube portion arranged on the inner periphery side of the lens frame 6 and the rotating frame 18, an annular and flat main lens frame annular portion 25b that is connected to the front end of the tube portion 25a and spreads radially outward like a brim, and a cylindrical tube portion 25c that protrudes forward from the outer periphery side of the annular portion 25b. The main lens frame 25 also includes an attachment portion 25d to which a cam follower 30 is attached.

The annular portion 25b is disposed in front of the rotating frame 18. Specifically, the annular portion 25b is disposed in front of the flange portion 18a of the rotating frame 18. The tube portion 25a is formed in a cylindrical shape. A recess 25e that is recessed radially inward is formed on the outer peripheral surface of the front portion of the tube portion 25a. The recess 25e is formed over the entire circumferential area. A male helicoid screw that engages with a female helicoid screw formed on the inner peripheral surface of the rotating frame 18 is formed on the outer peripheral surface of the tube portion 25a in front of the recess 25e. That is, the lens frame 5 and the rotating frame 18 are helicoidally engaged. Therefore, as described above, when the rotating frame 18 rotates with the front-rear direction as the axial direction of rotation relative to the lens frame 5, it moves in the front-rear direction relative to the lens frame 5.

The fixing frame 27 is disposed on the outer periphery of the cylindrical portion 25c. The fixing frame 27 is fixed to the cylindrical portion 25c. Specifically, the front portion of the fixing frame 27 is disposed on the cylindrical portion 25c by the fixing screw 31. The rear portion of the fixing frame 27 is formed with a screw hole 27a into which the fixing screw 23 engages. The screw holes 27a are disposed at three locations with a pitch of 120° centered on the optical axis L. The screw holes 27a penetrate the fixing frame 27 in the radial direction. The radial outer end of the fixing screw 23 that engages with the screw hole 27a is disposed radially inward from the outer periphery of the fixing frame 27. The fixed portion 18b of the rotating frame 18 is fixed to the main lens frame 25 by the fixing screw 23 in a state where it is sandwiched between the outer periphery of the cylindrical portion 25c and the rear portion of the fixing frame 27 in the radial direction. The tip of the fixing screw 23 contacts the outer periphery of the fixed portion 18b with a predetermined contact pressure.

The fixing frame 27 is disposed radially inward of the linear barrel 11 and the cam barrel 12. That is, the fixing screw 23 that engages with the screw hole 27a is disposed radially inward of the linear barrel 11 and the cam barrel 12. In this embodiment, when the lenses 2 and 3 are disposed at the telephoto end, the fixing screw 23 is disposed on the inner periphery side of the linear barrel 11 and the cam barrel 12, and overlaps with the linear barrel 11 and the cam barrel 12 in the radial direction. On the other hand, when the lenses 2 and 3 are disposed at the wide-angle end, the fixing screw 23 is disposed on the inner periphery side of the linear barrel 11.

The mounting portion 25d protrudes forward and radially outward from the front end of the tube portion 25c. As described above, the cam follower 30 is attached to the mounting portion 25d. The cam follower 30 protrudes radially outward from the front end of the main lens frame 25. The cam follower 30 is attached to the mounting portion 25d by a fixing screw. The cam follower 30 engages with the linear groove 11a of the linear barrel 11 and the cam groove 12a of the cam barrel 12.

The adjustment frame 26 includes a cylindrical portion 26a serving as a first cylindrical adjustment frame portion arranged on the outer periphery of the lens frame 6, a cylindrical portion 26b serving as a second cylindrical adjustment frame portion arranged on the inner periphery of the lens frame 6, and a circular portion 26c (see FIG. 3) serving as a flat, annular adjustment frame portion that connects the front end of the cylindrical portion 26a with the front end of the cylindrical portion 26b and is arranged between the rotating frame 18 and the lens frame 6 in the optical axis direction (front-rear direction). The adjustment frame 26 in this embodiment is composed of two approximately semi-cylindrical frame members that are divided into two in the radial direction, and the adjustment frame 26 is formed by combining the two frame members in the radial direction and fixing them to each other.

The tube portion 26a is formed in a substantially cylindrical shape. The tube portion 26a has a screw hole 26d with which the adjustment screw 22 engages. That is, the lens frame 5 has the screw hole 26d. The screw hole 26d is formed at the front end of the tube portion 26a. The screw hole 26d penetrates the tube portion 26a in the radial direction. The screw holes 26d are formed at four locations at a 90° pitch centered on the optical axis L. The radial outer end of the adjustment screw 22 that engages with the screw hole 26d is disposed radially inward from the outer circumferential surface of the adjustment frame 26 (specifically, the outer circumferential surface of the tube portion 26a). The fixing frame 28 is disposed on the inner circumferential side of the rear end of the tube portion 26a. The fixing frame 28 is fixed to the tube portion 26a by the fixing screw 32.

The tube portion 26b is formed in a cylindrical shape. The tube portion 26b is disposed on the outer periphery of the tube portion 25a of the main lens frame 25. The radially inner portion of the tube portion 26b is disposed in the recess 25e. The tube portion 26b is fixed to the tube portion 25a by a fixing screw (not shown). As described above, the ball 20 is disposed between the rotating frame 18 and the lens frame 6 in the front-rear direction. The annular portion 26c is formed with a ball arrangement hole 26e in which the ball 20 is disposed. The ball arrangement hole 26e penetrates the annular portion 26c in the front-rear direction. The ball arrangement hole 26e is formed in eight places at a 45° pitch around the optical axis L. The thickness of the annular portion 26c in the front-rear direction is thinner than the outer diameter of the ball 20.

The adjustment frame 26 is disposed radially inward from the front end of the lens frame 7 where the through hole 7a is formed. The adjustment frame 26 is also disposed radially inward from the fixed barrel 8, the linear barrel 11, and the cam barrel 12. That is, the adjustment screw 22 that engages with the screw hole 26d is disposed radially inward from the front end of the lens frame 7, the fixed barrel 8, the linear barrel 11, and the cam barrel 12. In this embodiment, when the lenses 2 and 3 are disposed at the telephoto end, the adjustment screw 22 is disposed on the inner periphery side of the linear barrel 11 and the cam barrel 12, and overlaps with the linear barrel 11 and the cam barrel 12 in the radial direction. On the other hand, when the lenses 2 and 3 are disposed at the wide-angle end, the adjustment screw 22 is disposed on the inner periphery side of the front end of the lens frame 7 and the fixed barrel 8, and overlaps with the front end of the lens frame 7 and the fixed barrel 8 in the radial direction.

As described above, the lens frame 6 is formed in a stepped, approximately cylindrical shape. The rear end of the lens frame 6 is located rearward of the rear end of the lens frame 5. The lens 3 is attached to the inner periphery of the rear end of the lens frame 6. The lens frame 6 is composed of a large diameter portion that constitutes the front portion of the lens frame 6 and a small diameter portion that constitutes the rear portion of the lens frame 6 and has a smaller outer diameter than the large diameter portion, and an annular step surface 6a is formed at the boundary between the large diameter portion and the small diameter portion. The step surface 6a is a flat surface that is perpendicular to the front-rear direction. The step surface 6a is formed forward of the fixed frame 28.

A V groove 6b is formed on the outer peripheral surface of the lens frame 6, in which the tip of the adjustment screw 22 is placed. The V groove 6b is formed at the front end of the lens frame 6. The V groove 6b is formed over the entire circumferential area. The front side of the V groove 6b is an inclined surface that slopes forward as it moves radially outward, and the rear side of the V groove 6b is an inclined surface that slopes backward as it moves radially outward. As described above, the tip of the adjustment screw 22 is formed in a cone shape. The tip of the adjustment screw 22 is in contact with one side of the V groove 6b.

The compression coil spring 21 is disposed between the flange portion 18a of the rotating frame 18 and the annular portion 26c of the adjustment frame 26 in the front-rear direction. As described above, the compression coil spring 21 biases the rotating frame 18 forward relative to the lens frame 5. That is, the compression coil spring 21 biases the rotating frame 18 toward the annular portion 25b disposed in front of the rotating frame 18. The compression coil spring 19 is disposed between the stepped surface 6a of the lens frame 6 and the fixed frame 28 in the front-rear direction. As described above, the compression coil spring 19 biases the lens frame 6 forward relative to the lens frame 5.

A thin plate 33 is disposed between the ball 20 and the rotating frame 18 in the front-to-rear direction, and a thin plate 34 is disposed between the ball 20 and the lens frame 6 in the front-to-rear direction. The rotating frame 18 and the thin plate 33 are in contact with each other at a predetermined contact pressure, and the ball 20 and the thin plate 33 are in contact with each other at a predetermined contact pressure. In addition, the lens frame 6 and the thin plate 34 are in contact with each other at a predetermined contact pressure, and the ball 20 and the thin plate 34 are in contact with each other at a predetermined contact pressure.

The thin plate 33 is a member for preventing direct contact between the ball 20 and the rotating frame 18. The thin plate 34 is a member for preventing direct contact between the ball 20 and the lens frame 6. The ball 20 is biased toward the rotating frame 18 via the lens frame 6 by the compression coil spring 19. Therefore, when the ball 20 and the rotating frame 18 are in contact, if the material of the ball 20 is harder than the material of the rotating frame 18, the ball 20 may bite into the rotating frame 18, causing dents or scratches on the rotating frame 18. Also, when the ball 20 and the lens 6 are in contact, if the material of the ball 20 is harder than the material of the lens frame 6, the ball 20 may bite into the lens 6, causing dents or scratches on the lens frame 6.

In this embodiment, the material of the thin plates 33, 34 is harder than the material of the lens frame 6 and the rotating frame 18, and the thin plate 33 is sandwiched between the ball 20 and the rotating frame 18, and the thin plate 34 is sandwiched between the ball 20 and the lens frame 6. This makes it possible to prevent dents and scratches on the lens frame 6 and the rotating frame 18. In addition, by making the contact surfaces of the thin plates 33, 34 with the ball 20 smooth or by applying a low-friction coating or the like to the contact surfaces of the thin plates 33, 34 with the ball 20, it is possible to smooth the rotation and sliding of the ball 20 and make adjustment easier.

When the rotating frame 18 rotates relative to the lens frame 5 and moves in the optical axis direction (front-to-back direction) before the rotating frame 18 is fixed by the fixing screw 23, the lens frame 6 moves in the front-to-back direction together with the ball 20 and the thin plates 33, 34, and the front-to-back position of the lens frame 6 relative to the lens frame 5 changes. In this embodiment, the front-to-back position of the lens frame 6 relative to the lens frame 5 is adjusted by the rotating frame 18. In other words, the front-to-back position of the lens frame 6 relative to the lens frame 5 is finely adjusted by rotating the rotating frame 18 relative to the lens frame 5 before the rotating frame 18 is fixed by the fixing screw 23. When rotating the rotating frame 18, the gear portion 18c is turned using a specified jig.

In addition, the lens frame 6 moves radially depending on the amount that the adjustment screw 22 is screwed into the screw hole 26d, and the radial position of the lens frame 6 relative to the lens frame 5 changes. In this embodiment, the radial position of the lens frame 6 relative to the lens frame 5 is adjusted by the adjustment screw 22. In other words, the radial position of the lens frame 6 relative to the lens frame 5 is fine-tuned by adjusting the amount that the adjustment screw 22 is screwed into the screw hole 26d.

When the lenses 2 and 3 are positioned at the wide-angle end, the adjustment screw 22 is positioned at the same position in the front-rear and circumferential directions as the through-hole 7a of the lens frame 7 and the through-hole 8a of the fixed barrel 8, and the adjustment screw 22 and the through-holes 7a and 8a overlap in the radial direction. When the lenses 2 and 3 are positioned at the telephoto end, the adjustment screw 22 is positioned at the same position in the front-rear and circumferential directions as the through-hole 11b of the linear barrel 11 and the through-hole 12b of the cam barrel 12, and the adjustment screw 22 and the through-holes 11b and 12b overlap in the radial direction.

When the lenses 2 and 3 are positioned at the telephoto end, the gear portion 18c is positioned at the same position in the front-rear direction as the through hole 11c of the linear barrel 11 and the through hole 12c of the cam barrel 12, and a portion of the gear portion 18c overlaps with the through holes 11c and 12c in the radial direction. When the lenses 2 and 3 are positioned at the telephoto end, the fixing screw 23 is positioned at the same position in the front-rear direction and circumferential direction as the through hole 11d of the linear barrel 11 and the through hole 12d of the cam barrel 12, and the fixing screw 23 overlaps with the through holes 11d and 12d in the radial direction.

In this embodiment, it is possible to adjust the amount of screwing of the adjustment screw 22 into the screw hole 26d (i.e., adjust the radial position of the lens frame 6 relative to the lens frame 5) in both states, when the lenses 2 and 3 are positioned at the wide-angle end and when the lenses 2 and 3 are positioned at the telephoto end. When adjusting the amount of screwing of the adjustment screw 22 into the screw hole 26d when the lenses 2 and 3 are positioned at the wide-angle end, a part of the tool for turning the adjustment screw 22 passes through the through holes 7a and 8a. Specifically, the tip of the screwdriver for turning the adjustment screw 22 passes through the through holes 7a and 8a.

When adjusting the amount of screwing of the adjustment screw 22 into the screw hole 26d with the lenses 2 and 3 positioned at the telephoto end, a part of the tool for turning the adjustment screw 22 passes through the through holes 11b and 12b. Specifically, the tip of the screwdriver for turning the adjustment screw 22 passes through the through holes 11b and 12b. The through holes 7a, 8a, 11b and 12b in this embodiment are second through holes for passing a part of the tool for turning the adjustment screw 22. In addition, the lens frame 7, fixed barrel 8, linear barrel 11 and cam barrel 12 in this embodiment are second barrel members positioned outside the adjustment screw 22 in the radial direction.

When the radial position adjustment of the lens frame 6 relative to the lens frame 5 is completed, the adjustment screw 22 is fixed to the adjustment frame 26 by adhesive. At this time, adhesive is applied from the outer periphery of the fixed cylinder 8 and the cam cylinder 12 using the through holes 7a, 8a, 11b, and 12b. In addition, a through hole (not shown) is formed in the cylinder portion 26a of the adjustment frame 26 for adhesively fixing the lens frame 6 to the cylinder portion 26a. This through hole penetrates the cylinder portion 26a in the radial direction. This through hole is formed in the same position as the screw hole 26d in the front-rear direction. In addition, this through hole is formed in a position offset from the screw hole 26d in the circumferential direction. In addition, this through hole is formed in four places at a 90° pitch centered on the optical axis L.

Adhesive is applied to the through hole of the tube portion 26a from the outer periphery of the fixed tube 8 and the cam tube 12. The lens frame 7, the fixed tube 8, the linear tube 11, and the cam tube 12 are formed with work through holes (not shown) for applying adhesive to the through hole of the tube portion 26a. These work through holes are formed in the same positions as the through holes 7a, 8a, 11b, and 12b in the front-rear direction. Furthermore, these work through holes are formed in positions offset from the through holes 7a, 8a, 11b, and 12b in the circumferential direction. Furthermore, these work through holes are formed in four places at a 90° pitch around the optical axis L.

In addition, in this embodiment, when the lenses 2 and 3 are positioned at the telephoto end, the rotating frame 18 can be rotated relative to the lens frame 5 to adjust the front-rear position of the lens frame 6 relative to the lens frame 5. When adjusting the front-rear position of the lens frame 6 relative to the lens frame 5, a part of a jig for rotating the gear portion 18c passes through the through holes 11c and 12c. Specifically, the tip of a jig having a gear train including a gear that engages with the gear portion 18c passes through the through holes 11c and 12c. In this embodiment, the through holes 11c and 12c are first through holes for passing a part of the jig for rotating the gear portion 18c. In addition, the linear cylinder 11 and the cam cylinder 12 in this embodiment are first cylinder members that are arranged on the outer periphery side of the rotating frame 18.

When adjustment of the front-rear position of the lens frame 6 relative to the lens frame 5 is completed, the rotating frame 18 is fixed to the lens frame 5 by the fixing screw 23 with the lenses 2 and 3 positioned at the telephoto end. At this time, the tip of the screwdriver used to turn the fixing screw 23 passes through the through holes 11d and 12d. In this embodiment, in order to prevent the fixing screw 23 tightened into the screw hole 27a from loosening, the fixing screw 23 is fixed to the fixed frame 27 by adhesive. At this time, adhesive is applied from the outer periphery side of the cam barrel 12 using the through holes 11d and 12d.

A through hole is formed in the rear portion of the fixed frame 27 for adhesively fixing the fixed portion 18b to the fixed frame 27. This through hole penetrates the fixed frame 27 in the radial direction. This through hole is formed in the same position as the screw hole 27a in the front-rear direction. This through hole is also formed in a position offset from the screw hole 27a in the circumferential direction. This through hole is also formed in three places at a pitch of 120° around the optical axis L, for example.

Adhesive is applied to the through holes of the fixed frame 27 from the outer periphery of the cam barrel 12. The linear barrel 11 and the cam barrel 12 have work through holes formed therein for applying adhesive to the through holes of the fixed frame 27. These work through holes are formed in the same positions as the through holes 11d and 12d in the front-to-rear direction. Furthermore, these work through holes are formed in positions offset from the through holes 11d and 12d in the circumferential direction. Furthermore, these work through holes are formed in three locations, for example, at a 120° pitch around the optical axis L.

(Main effects of this embodiment)
As described above, the lens barrel 1 of this embodiment includes the lens frame 5 that holds the lens 2 on the inner periphery side, the lens frame 6 that holds the lens 3 on the inner periphery side, the first adjustment mechanism 14 for adjusting the position of the lens frame 6 in the optical axis direction relative to the lens frame 5 by moving the lens frame 6 in the optical axis direction relative to the lens frame 5, and the second adjustment mechanism 15 for adjusting the radial position of the lens frame 6 in the radial direction relative to the lens frame 5 by moving the lens frame 6 in the radial direction relative to the lens frame 5. The first adjustment mechanism 14 includes a rotating frame 18 that is disposed on the outer periphery side of the lens frame 5, is rotatably held by the lens frame 5 with the optical axis direction as the axis of rotation, and moves in the optical axis direction relative to the lens frame 5 when rotated with the optical axis direction as the axis of rotation, and a compression coil spring 19 that urges the lens frame 6 forward relative to the lens frame 5. The rotating frame 18 is disposed on the front side of the lens frame 6, and the compression coil spring 19 urges the lens frame 6 toward the rotating frame 18. When the rotating frame 18 rotates relative to the lens frame 5 and moves in the optical axis direction, the lens frame 6 moves in the optical axis direction relative to the lens frame 5. The second adjustment mechanism 15 includes a plurality of adjustment screws 22 that are arranged circumferentially around the lens frame 5 and contact the lens frame 6 from the radial outside, and a plurality of screw holes 26d are formed in the lens frame 5 with which the adjustment screws 22 engage. In addition, the position of the lens frame 6 in the optical axis direction relative to the lens frame 5 is adjusted by the rotating frame 18, and the radial position of the lens frame 6 in relation to the lens frame 5 is adjusted by the adjustment screws 22.

In this way, the lens barrel 1 of this embodiment is equipped with a first adjustment mechanism 14 for adjusting the position of the lens frame 6 in the optical axis direction relative to the lens frame 5 by moving the lens frame 6 in the optical axis direction relative to the lens frame 5, and a second adjustment mechanism 15 for adjusting the radial position of the lens frame 6 in the radial direction relative to the lens frame 5 by moving the lens frame 6 in the radial direction relative to the lens frame 5, and the optical axis direction position and radial position of the lens 3 held in the lens frame 6 can be adjusted. Therefore, in this embodiment, even if the zoom lens group held in the lens frames 5, 6 includes a lens 3 with a large effect, it is possible to ensure the optical performance of the zoom lens group including the lens 3 with a large effect.

In addition, in this embodiment, the position of the lens frame 6 in the optical axis direction relative to the lens frame 5 is adjusted by a rotating frame 18 that is rotatably held on the outer periphery of the lens frame 5, and the radial position of the lens frame 6 in the optical axis direction relative to the lens frame 5 is adjusted by an adjustment screw 22 that engages with a screw hole 26d in the lens frame 5, so that the optical axis direction position and radial position of the lens frame 6 can be adjusted independently. Therefore, in this embodiment, it is easy to adjust the position of the lens frame 6.

As in this embodiment, the first adjustment mechanism 14 is preferably provided with a plurality of balls 20 that are disposed between the rotating frame 18 and the lens frame 6 in the optical axis direction and arranged in the circumferential direction. In this way, it is possible to reduce the sliding resistance of the rotating frame 18 relative to the lens frame 6 when the rotating frame 18 rotates. Therefore, it is possible to smoothly rotate the rotating frame 18 relative to the lens frame 5.

As in this embodiment, the main lens frame 25 has a circular, flat, annular portion 25b that is connected to the front end of the tube portion 25a and is disposed in front of the rotating frame 18, and the first adjustment mechanism 14 preferably has a compression coil spring 21 that is disposed between the rotating frame 18 and the adjustment frame 26 in the optical axis direction and biases the rotating frame 18 toward the annular portion 25b. In this way, it is possible to effectively suppress rattling of the rotating frame 18 relative to the lens frame 5 in the optical axis direction. Specifically, it is possible to effectively suppress rattling between the female helicoid screw formed on the inner peripheral surface of the rotating frame 18 and the male helicoid screw formed on the outer peripheral surface of the tube portion 25a.

As in this embodiment, the lens barrel 1 preferably includes a fixing screw 23 for fixing the rotating frame 18 to the lens frame 5. In this way, it is possible to reliably fix the rotating frame 18 so that it does not rotate after adjusting the position of the lens frame 6 in the optical axis direction.

As in this embodiment, it is preferable that the lens frame 5 and the rotating frame 18 are helicoidally engaged. In this way, it is possible to move the rotating frame 18 in the optical axis direction relative to the lens frame 5 when the rotating frame 18 is rotated relative to the lens frame 5 with a relatively simple configuration.

As in this embodiment, a V-groove 6b in which the tip of the adjustment screw 22 is placed is formed on the outer peripheral surface of the lens frame 6, and it is preferable that the tip of the adjustment screw 22 contacts the side of the V-groove 6b. In this way, it becomes possible to restrict the movement of the lens frame 6 in the optical axis direction by the adjustment screw 22.

As in this embodiment, it is preferable that the lens frame 7 has a through hole 7a through which a part of the tool for turning the adjustment screw 22 passes, and the fixed barrel 8 has a through hole 8a through which a part of the tool for turning the adjustment screw 22 passes. In this way, even if the lens frame 7 and the fixed barrel 8 are arranged outside the adjustment screw 22 in the radial direction, it is possible to turn the adjustment screw 22 with a tool in the assembled state of the lens barrel 1. Therefore, even if the lens frame 7 and the fixed barrel 8 are arranged outside the adjustment screw 22 in the radial direction, it is possible to adjust the radial position of the lens frame 6 relative to the lens frame 5 without disassembling the lens barrel 1, and as a result, it is possible to easily adjust the radial position of the lens frame 6 relative to the lens frame 5.

As in this embodiment, it is preferable that the linear cylinder 11 has a through hole 11c through which a part of the jig for rotating the gear part 18c passes and a through hole 11b through which a part of the tool for rotating the adjustment screw 22 passes, and the cam cylinder 12 has a through hole 12c through which a part of the jig for rotating the gear part 18c passes and a through hole 12b through which a part of the tool for rotating the adjustment screw 22 passes. In this way, even if the linear cylinder 11 and the cam cylinder 12 are arranged on the outer periphery side of the lens frames 5, 6, the first adjustment mechanism 14, and the second adjustment mechanism 15, it becomes possible to rotate the rotating frame 18 by rotating the gear part 18c with a jig and to rotate the adjustment screw 22 with a tool when the lens barrel 1 is assembled. Therefore, even if the linear cylinder 11 and cam cylinder 12 are arranged on the outer periphery of the lens frames 5, 6, the first adjustment mechanism 14, and the second adjustment mechanism 15, it is possible to adjust the optical axis position and radial position of the lens frame 6 relative to the lens frame 5 without disassembling the lens barrel 1, and as a result, it is possible to easily adjust the optical axis position and radial position of the lens frame 6 relative to the lens frame 5.

Other Embodiments
In the above-mentioned embodiment, the number of balls 20 provided in the first adjustment mechanism 14 may be nine or more, or may be a plural number of seven or less. In addition, in the above-mentioned embodiment, the number of adjustment screws 22 provided in the second adjustment mechanism 15 may be three, or may be five or more. Furthermore, in the above-mentioned embodiment, the number of fixing screws 23 provided in the lens barrel 1 may be two, or may be four or more. In the above-mentioned embodiment, the first biasing member that biases the lens frame 6 may be a spring member other than the compression coil spring 19, and the second biasing member that biases the rotating frame 18 forward may be a spring member other than the compression coil spring 21.

In the above-mentioned embodiment, the first adjustment mechanism 14 may have, instead of the ball 20, a plurality of cylindrical rollers arranged between the rotating frame 18 and the lens frame 6 in the front-rear direction. In this case, for example, the plurality of rollers are arranged so that the axial direction of the cylindrical rollers coincides with the radial direction perpendicular to the optical axis direction. The plurality of rollers may also be arranged so that the axial direction of the rollers coincides with the optical axis direction. In this case, the arrangement holes in which the rollers are arranged are formed in the annular portion 26c of the adjustment frame 26. In addition, in the above-mentioned embodiment, a plurality of protrusions protruding toward the front side may be formed on the lens frame 6 instead of the ball 20. In this case, the tip of the protrusion formed on the lens frame 6 is in contact with the thin plate 33 or the rotating frame 18. In this case, the arrangement holes in which the protrusions formed on the lens frame 6 are arranged are formed in the annular portion 26c.

In the above embodiment, the lens frame 5 and the rotating frame 18 are helicoidally engaged, but the lens frame 5 and the rotating frame 18 may be cam-engaged or may be threadedly engaged other than helicoidally engaged. In addition, in the above embodiment, the V-groove 6b does not have to be formed on the outer peripheral surface of the lens frame 6. In this case, for example, like the fixing screw 23, the outer peripheral surface of the tip of the adjustment screw 22 is formed in a truncated cone shape, and the tip of the adjustment screw 22 is recessed. Also, the tip of the adjustment screw 22 is in contact with the outer peripheral surface of the lens frame 6.

In the above-mentioned embodiment, when the lenses 2 and 3 are arranged at the telephoto end, the gear part 18c may overlap only one of the linear barrel 11 and the cam barrel 12 in the radial direction. In this case, the through holes 11c and 12c and the through holes 11d and 12d are formed only in the linear barrel 11 or the cam barrel 12 that overlaps with the gear part 18c in the radial direction, through which a part of the tool for turning the gear part 18c passes. In the above-mentioned embodiment, when the lenses 2 and 3 are arranged at the telephoto end, the adjustment screw 22 may overlap only one of the linear barrel 11 and the cam barrel 12 in the radial direction. In this case, the through holes 11b and 12b are formed only in the linear barrel 11 or the cam barrel 12 that overlaps with the adjustment screw 22 in the radial direction, through which a part of the tool for turning the adjustment screw 22 passes.

In the above-described embodiment, a cylindrical tube member may be disposed on the outer periphery of the cam tube 12. This tube member is, for example, disposed on the outer periphery of the rotating frame 18 and disposed outside the adjustment screw 22 in the radial direction. In this case, the tube member is formed with a first through hole through which a part of a jig for turning the gear portion 18c passes, and a second through hole through which a part of a tool for turning the adjustment screw 22 passes. In this case, the tube member is both a first tube member and a second tube member.

In the above embodiment, when the lenses 2 and 3 are arranged at the wide-angle end, the rotating frame 18 may be rotated relative to the lens frame 5 to adjust the front-rear position of the lens frame 6 relative to the lens frame 5. In this case, for example, a first through hole through which a part of a jig for rotating the gear part 18c passes is formed in the fixed cylinder 8, and when adjusting the front-rear position of the lens frame 6 relative to the lens frame 5, a part of the jig for rotating the gear part 18c passes through this first through hole. In addition, in this case, for example, a through hole through which the tip of a screwdriver for turning the fixing screw 23 passes is formed in the linear cylinder 11. In this case, the fixed cylinder 8 is the first cylinder member arranged on the outer periphery of the rotating frame 18.

In addition, if it is possible to adjust the front-to-rear position of the lens frame 6 relative to the lens frame 5 when the lenses 2 and 3 are arranged at the wide-angle end, it is not necessary to be able to adjust the front-to-rear position of the lens frame 6 relative to the lens frame 5 when the lenses 2 and 3 are arranged at the telephoto end. In this case, the through holes 11c, 11d, 12c, and 12d do not need to be formed in the linear cylinder 11 and the cam cylinder 12.

In the above-mentioned embodiment, the screwing amount of the adjustment screw 22 into the screw hole 26d may be adjustable only when the lenses 2 and 3 are arranged at the wide-angle end or when the lenses 2 and 3 are arranged at the telephoto end. If the screwing amount of the adjustment screw 22 into the screw hole 26d is adjustable only when the lenses 2 and 3 are arranged at the wide-angle end, the through holes 11b and 12b may not be formed in the linear cylinder 11 and the cam cylinder 12. Also, if the screwing amount of the adjustment screw 22 into the screw hole 26d is adjustable only when the lenses 2 and 3 are arranged at the telephoto end, the through holes 7a and 8a may not be formed in the lens frame 7 and the fixed cylinder 8.

In the above-mentioned embodiment, the mechanism for moving the lens frames 5 and 6 in the front-rear direction relative to the fixed cylinder 8 may be a helicoid mechanism. Also, in the above-mentioned embodiment, the lens 2 and the lens 3 may form part of the focus lens group. Also, in the above-mentioned embodiment, the lenses 2 and 3 may be fixed lenses that do not move in the front-rear direction relative to the fixed cylinder 8. In this case, the lens frame 5 is fixed to the fixed cylinder 8. Also, in this case, the linear cylinder 11 and the cam cylinder 12 are not necessary.

1 Lens barrel 2, 3 Lens 5 Lens frame (first lens frame)
6 Lens frame (second lens frame)
6b V-groove 7 Lens frame (second barrel member)
7a Through hole (second through hole)
8 Fixed cylinder (second cylinder member)
8a Through hole (second through hole)
11 Straight-moving cylinder (first cylinder member, second cylinder member)
11a: straight groove; 11b: through hole (second through hole);
11c through hole (first through hole)
12 Cam barrel (first barrel member, second barrel member)
12a Cam groove 12b Through hole (second through hole)
12c through hole (first through hole)
14 First adjustment mechanism 15 Second adjustment mechanism 18 Rotation frame 18c Gear portion 19 Compression coil spring (first biasing member)
20 Ball 21 Compression coil spring (second biasing member)
22 Adjustment screw 23 Fixation screw 25 Main lens frame 25a Cylinder portion (main lens frame cylinder portion)
25b Circular portion (main lens frame circular portion)
26 Adjustment frame 26a Cylindrical part (first adjustment frame cylinder part)
26b Cylinder part (second adjustment frame cylinder part)
26c Circular ring portion (adjustment frame circular ring portion)
26d Screw hole 30 Cam follower Z1 First direction Z2 Second direction

Claims (9)

a first lens frame that holds a lens on its inner periphery, a second lens frame that holds a lens on its inner periphery, a first adjustment mechanism that moves the second lens frame relative to the first lens frame in an optical axis direction of the lens held in the second lens frame to adjust a position of the second lens frame in the optical axis direction relative to the first lens frame, and a second adjustment mechanism that moves the second lens frame relative to the first lens frame in a radial direction perpendicular to the optical axis direction to adjust the radial position of the second lens frame relative to the first lens frame,
the first adjustment mechanism includes a rotating frame that is disposed on an outer circumferential side of the first lens frame, is rotatably held by the first lens frame with the optical axis direction as an axial direction of rotation, and moves in the optical axis direction relative to the first lens frame when rotated with the optical axis direction as the axial direction of rotation, and a first biasing member that biases the second lens frame to one side in the optical axis direction relative to the first lens frame,
When one side in the optical axis direction, which is a biasing direction of the second lens frame by the first biasing member, is defined as a first direction side, and the opposite side to the first direction side is defined as a second direction side,
the rotating frame is disposed on a side of the second lens frame in the first direction,
the first biasing member biases the second lens frame toward the rotation frame,
when the rotating frame rotates with respect to the first lens frame and moves in the optical axis direction, the second lens frame moves in the optical axis direction with respect to the first lens frame,
the second adjustment mechanism includes a plurality of adjustment screws that are arranged in a circumferential direction of the first lens frame and contact the second lens frame from an outer side in the radial direction,
a plurality of screw holes into which the adjustment screws are engaged are formed in the first lens frame;
a position of the second lens frame relative to the first lens frame in the optical axis direction is adjusted by the rotating frame,
the radial position of the second lens frame relative to the first lens frame is adjusted by the adjustment screw ;
the first lens frame includes a main lens frame that holds the lens on an inner periphery side thereof, and an adjustment frame that is fixed to the main lens frame and is disposed on the second direction side of the rotating frame,
the main lens frame includes a cylindrical main lens frame cylinder portion that is disposed on an inner peripheral side of the second lens frame,
the adjustment frame comprises a cylindrical first adjustment frame cylinder portion that is arranged on the outer circumferential side of the second lens frame and in which the screw holes are formed, a cylindrical second adjustment frame cylinder portion that is arranged on the inner circumferential side of the second lens frame and fixed to the main lens frame cylinder portion, and a circular, flat adjustment frame annular portion that connects the first direction side end of the first adjustment frame cylinder portion and the first direction side end of the second adjustment frame cylinder portion and is arranged between the rotating frame and the second lens frame in the optical axis direction . The lens barrel according to claim 1, characterized in that the first adjustment mechanism includes a plurality of balls arranged in the circumferential direction and disposed between the rotating frame and the second lens frame in the optical axis direction. the main lens frame includes a main lens frame annular portion having an annular and flat shape that is connected to a side end of the main lens frame cylindrical portion in the first direction and that is disposed on a side of the rotating frame in the first direction,
3. The lens barrel according to claim 1, wherein the first adjustment mechanism includes a second biasing member that is disposed between the rotating frame and the adjustment frame in the optical axis direction and biases the rotating frame toward the main lens frame annular portion. 4. The lens barrel according to claim 1, further comprising a fixing screw for fixing the rotating frame to the first lens frame. 5. The lens barrel according to claim 1, wherein the first lens frame and the rotating frame are engaged in a helicoidal manner. a V-groove in which a tip end of the adjustment screw is to be placed is formed on an outer circumferential surface of the second lens frame,
6. The lens barrel according to claim 1 , wherein a tip of the adjustment screw is in contact with a side surface of the V-groove. the lens frame includes a first lens frame that holds a lens on its inner periphery side, a second lens frame that holds a lens on its inner periphery side, a first adjustment mechanism that moves the second lens frame relative to the first lens frame in an optical axis direction of the lens held in the second lens frame to adjust a position of the second lens frame relative to the first lens frame in the optical axis direction, a second adjustment mechanism that moves the second lens frame relative to the first lens frame in a radial direction perpendicular to the optical axis direction to adjust the radial position of the second lens frame relative to the first lens frame, and a rectilinear cylinder and a cam cylinder that are disposed on outer periphery sides of the first lens frame and the second lens frame,
the first adjustment mechanism includes a rotating frame that is disposed on an outer circumferential side of the first lens frame, is rotatably held by the first lens frame with the optical axis direction as an axial direction of rotation, and moves in the optical axis direction relative to the first lens frame when rotated with the optical axis direction as the axial direction of rotation, and a first biasing member that biases the second lens frame to one side in the optical axis direction relative to the first lens frame,
When one side in the optical axis direction, which is a biasing direction of the second lens frame by the first biasing member, is defined as a first direction side, and the opposite side to the first direction side is defined as a second direction side,
the rotating frame is disposed on a side of the second lens frame in the first direction,
the first biasing member biases the second lens frame toward the rotation frame,
when the rotating frame rotates with respect to the first lens frame and moves in the optical axis direction, the second lens frame moves in the optical axis direction with respect to the first lens frame,
the second adjustment mechanism includes a plurality of adjustment screws that are arranged in a circumferential direction of the first lens frame and contact the second lens frame from an outer side in the radial direction,
a plurality of screw holes into which the adjustment screws are engaged are formed in the first lens frame;
a position of the second lens frame relative to the first lens frame in the optical axis direction is adjusted by the rotating frame,
the radial position of the second lens frame relative to the first lens frame is adjusted by the adjustment screw;
The linear barrel is formed with a linear groove having a longitudinal direction along the optical axis direction,
A cam groove is formed in the cam barrel,
a cam follower that engages with the rectilinear groove and the cam groove is attached to the first lens frame ;
A gear portion having a plurality of teeth is formed on the outer circumferential surface of the rotating frame,
the gear portion overlaps with at least one of the linear motion barrel and the cam barrel in the radial direction,
the adjustment screw overlaps with at least one of the linear movement barrel and the cam barrel in the radial direction,
a first through hole through which a part of a jig for rotating the gear portion passes is formed in at least one of the linear motion cylinder and the cam cylinder overlapping with the gear portion in the radial direction, the first through hole being formed so as to pass through in the radial direction,
a second through hole for allowing a portion of a tool for turning the adjustment screw to pass therethrough, the second through hole being formed so as to penetrate the first through hole in the radial direction, and the second through hole being formed in at least one of the linear barrel and the cam barrel which overlap with the adjustment screw in the radial direction, the second through hole allowing a portion of a tool for turning the adjustment screw to pass therethrough. the lens frame includes a first lens frame that holds a lens on its inner periphery side, a second lens frame that holds a lens on its inner periphery side, a first adjustment mechanism that moves the second lens frame relative to the first lens frame in an optical axis direction of the lens held in the second lens frame to adjust a position of the second lens frame relative to the first lens frame in the optical axis direction, a second adjustment mechanism that moves the second lens frame relative to the first lens frame in a radial direction perpendicular to the optical axis direction to adjust the radial position of the second lens frame relative to the first lens frame, and a cylindrical first barrel member,
the first adjustment mechanism includes a rotating frame that is disposed on an outer circumferential side of the first lens frame, is rotatably held by the first lens frame with the optical axis direction as an axial direction of rotation, and moves in the optical axis direction relative to the first lens frame when rotated with the optical axis direction as the axial direction of rotation, and a first biasing member that biases the second lens frame to one side in the optical axis direction relative to the first lens frame,
When one side in the optical axis direction, which is a biasing direction of the second lens frame by the first biasing member, is defined as a first direction side, and the opposite side to the first direction side is defined as a second direction side,
the rotating frame is disposed on a side of the second lens frame in the first direction,
the first biasing member biases the second lens frame toward the rotation frame,
when the rotating frame rotates with respect to the first lens frame and moves in the optical axis direction, the second lens frame moves in the optical axis direction with respect to the first lens frame,
the second adjustment mechanism includes a plurality of adjustment screws that are arranged in a circumferential direction of the first lens frame and contact the second lens frame from an outer side in the radial direction,
a plurality of screw holes into which the adjustment screws are engaged are formed in the first lens frame;
a position of the second lens frame relative to the first lens frame in the optical axis direction is adjusted by the rotating frame,
the radial position of the second lens frame relative to the first lens frame is adjusted by the adjustment screw;
the first cylindrical member is disposed on an outer circumferential side of the rotating frame ,
A gear portion having a plurality of teeth is formed on the outer circumferential surface of the rotating frame,
a first through hole is formed in the first cylindrical member, through which a part of a jig for rotating the gear portion passes;
The lens barrel, wherein the first through hole penetrates the first cylindrical member in the radial direction. the lens frame includes a first lens frame that holds a lens on its inner periphery side, a second lens frame that holds a lens on its inner periphery side, a first adjustment mechanism that moves the second lens frame relative to the first lens frame in an optical axis direction of the lens held in the second lens frame to adjust a position of the second lens frame relative to the first lens frame in the optical axis direction, a second adjustment mechanism that moves the second lens frame relative to the first lens frame in a radial direction perpendicular to the optical axis direction to adjust the radial position of the second lens frame relative to the first lens frame, and a cylindrical second barrel member,
the first adjustment mechanism includes a rotating frame that is disposed on an outer circumferential side of the first lens frame, is rotatably held by the first lens frame with the optical axis direction as an axial direction of rotation, and moves in the optical axis direction relative to the first lens frame when rotated with the optical axis direction as the axial direction of rotation, and a first biasing member that biases the second lens frame to one side in the optical axis direction relative to the first lens frame,
When one side in the optical axis direction, which is a biasing direction of the second lens frame by the first biasing member, is defined as a first direction side, and the opposite side to the first direction side is defined as a second direction side,
the rotating frame is disposed on a side of the second lens frame in the first direction,
the first biasing member biases the second lens frame toward the rotation frame,
when the rotating frame rotates with respect to the first lens frame and moves in the optical axis direction, the second lens frame moves in the optical axis direction with respect to the first lens frame,
the second adjustment mechanism includes a plurality of adjustment screws that are arranged in a circumferential direction of the first lens frame and contact the second lens frame from an outer side in the radial direction,
a plurality of screw holes into which the adjustment screws are engaged are formed in the first lens frame;
a position of the second lens frame relative to the first lens frame in the optical axis direction is adjusted by the rotating frame,
the radial position of the second lens frame relative to the first lens frame is adjusted by the adjustment screw;
the second cylindrical member is disposed on an outer side of the adjustment screw in the radial direction ,
The second cylindrical member has a second through hole through which a part of a tool for turning the adjustment screw passes,
The lens barrel, wherein the second through hole penetrates the second cylindrical member in the radial direction.

Images