JP2001033684A - Lens-barrel and optical instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact lens-barrel of which plural movable lens groups are driven using driving force of one driving source, and of which full barrel length and the projected area in the optical axis direction are short and small. SOLUTION: This lens-barrel is constituted by providing the first lens holding member 17 driven in the optical axis direction by a driving source (for example, by engaging with a lead screw rotation-driven by a motor), a turning member 16 attached to a fixed barrel constituting member (for example, a fixed lens holding member 12) to be turnable toward an optical axis direction, and turn- driven by the first lens holding member 17 movable in the optical axis direction, and the second lens holding member 9 driven in the optical axis direction by the turning member 16 turned.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens barrel used for an image pickup apparatus such as a video camera and other optical instruments.

[0002]

2. Description of the Related Art As a zoom lens for a video camera, for example, there is a zoom lens composed of four lens groups of a fixed convex, a movable concave, a fixed convex, and a movable convex in order from the subject side.

FIGS. 8A and 8B show a lens barrel structure of a general zoom lens having a four-group lens structure. (B) shows a cross section taken along line AA in (A).

The four lens groups 201a to 201d constituting the zoom lens are composed of a fixed front lens 201.
a, a variator lens group 201b that performs a zooming operation by moving along the optical axis, a fixed afocal lens 201c, and a focal plane maintenance and focusing during zooming by moving along the optical axis. And a forcing lens group 201d.

The guide bars 203, 204a, and 204b are arranged in parallel with the optical axis 205, and guide and stop the moving lens group. The DC motor 206 is a driving source for moving the variator lens group 201b.

The front lens 201a is held by the front lens barrel 202, and the variator lens group 201b is
It is held at 1. Also, the afocal lens 201
c denotes an intermediate frame 215 and a focusing lens group 201d.
Are held by the RR moving ring 214.

The front lens barrel 202 is positioned and fixed to a rear lens barrel 216. A guide bar 203 is positioned and supported by the two lens barrels 202 and 216, and a guide screw shaft 208 is rotatably supported. I have.
The guide screw shaft 208 is driven to rotate by the rotation of the output shaft 206 a of the DC motor 206 being transmitted through a gear train 207.

A V-moving ring 211 for holding the variator lens group 201b includes a pressing spring 209 and the pressing spring 20.
And a ball 210 which engages with a screw groove 208a formed in the guide screw shaft 208 by a force of 9 by the DC motor 206.
By being driven to rotate, 8 moves forward and backward in the optical axis direction while being guided and regulated by the guide bar 203.

Guide bars 204a, 204 are provided on the rear barrel 216 and the intermediate frame 215 positioned in the rear barrel 216.
04b is fitted and supported. The RR moving ring 214 can advance and retreat in the optical axis direction while being guided and rotated by the guide bars 204a and 204b.

Guide bars 204a and 204 are provided on an RR moving ring 214 for holding the focusing lens group 201d.
b is formed with a sleeve portion that is slidably fitted to the RR moving ring 2 in the optical axis direction.
14 and are integrated with each other.

The stepping motor 212 rotationally drives a lead screw 212a formed integrally with its output shaft. The RR moving ring 21 is attached to the lead screw 212a.
The RR moving ring 214 moves in the optical axis direction while being guided by the guide bars 204a and 204b by the rotation of the lead screw 212a with the engagement of the rack 213 assembled to the rack 4.

As a drive source for the variator lens group, a stepping motor may be used in the same manner as the drive source for the focusing lens group.

The front lens barrel 202, the intermediate frame 215, and the rear lens barrel 216 form a lens barrel body that substantially accommodates a lens or the like.

When the lens group holding frame is moved by using such a stepping motor, after detecting that the holding frame is located at one reference position in the optical axis direction using a photo interrupter or the like, The absolute position of the holding frame is detected by continuously counting the number of drive pulses applied to the stepping motor.

FIG. 9 shows an electrical configuration of a camera body in a conventional imaging apparatus. In this figure, FIG.
The components of the lens barrel described in (1) are given the same reference numerals as in FIG.

Reference numeral 221 denotes a solid-state imaging device such as a CCD;
Denotes a drive mechanism of the variator lens group 201b, and includes a motor 206 (or a stepping motor), a gear train 207.
And a guide screw shaft 208 and the like.

Reference numeral 223 denotes a focusing lens group 201d.
And includes a stepping motor 212, a lead screw shaft 212a, a rack 213, and the like.

Reference numeral 224 denotes a drive mechanism of the diaphragm device 235 disposed between the variator lens group 201b and the afocal lens 201c.

Reference numeral 225 denotes a zoom encoder, and 227 denotes a focus encoder. Each of these encoders detects the absolute position of the variator lens group 201b and the focusing lens group 201d in the optical axis direction. When a DC motor is used as the variator drive source, an absolute position encoder such as a volume or a magnetic type is used.

When a stepping motor is used as a drive source, a method of continuously counting the number of operation pulses input to the stepping motor after arranging the holding frame at the reference position as described above is used. General.

Reference numeral 226 denotes a diaphragm encoder, which employs a method in which a Hall element is disposed inside a motor serving as a diaphragm driving source and which detects the rotational positional relationship between a rotor and a stator.

A CPU 232 controls the camera. A camera signal processing circuit 228 performs predetermined amplification, gamma correction, and the like on the output of the solid-state imaging device 221. The contrast signal of the video signal that has undergone these predetermined processes passes through the AE gate 229 and the AF gate 230. That is, the optimum signal extraction range for exposure determination and focusing is set by this gate in the entire screen. The size of this gate is variable,
There may be a case where a plurality is provided.

Reference numeral 231 denotes an AF signal processing circuit which processes an AF signal for AF (auto focus), and generates one or a plurality of outputs related to a high frequency component of a video signal. 233 is a zoom switch, and 234 is a zoom tracking memory. Zoom tracking memory 234
Stores information on the focusing lens position to be set in accordance with the subject distance and the variator lens position during zooming. Note that C is used as the zoom tracking memory.
The memory in the PU 232 may be used.

For example, the photographer sets the zoom switch 23
3 is operated, the CPU 232 determines the current variator as a detection result of the zoom encoder 225 so that the predetermined positional relationship between the variator lens and the focusing lens calculated based on the information of the zoom tracking memory 234 is maintained. The absolute position in the optical axis direction of the lens and the calculated position of the variator lens to be set, and the current absolute position of the focus lens in the optical axis direction as a detection result of the focus encoder 227 and the calculated focus lens should be set. The drive of the zoom drive mechanism 222 and the focussing drive mechanism 223 is controlled so that the positions match each other.

In the auto focus operation, the CPU 2 sets the output of the AF signal processing circuit 231 to a peak so that
Reference numeral 32 controls the driving of the focusing drive mechanism 223.

Further, in order to obtain an appropriate exposure, the CPU 2
Reference numeral 32 designates the average value of the output of the Y signal passing through the AE gate 229 as a predetermined value, and controls the drive of the aperture driving mechanism 224 so that the output of the aperture encoder 226 becomes the predetermined value, thereby controlling the aperture diameter.

In recent years, the photographing lens has been required to be reduced in size and diameter. However, conventionally, as the optical type most often used as a zoom lens for a video camera, a fixed convex, a movable concave, a fixed convex,
Although there is a lens composed of four movable convex lens groups, this optical type has a fixed front lens,
There is a problem that the total length of the lens barrel holding the optical system becomes long. Therefore, a collapsible lens barrel structure in which the position of the front lens is collapsed when stored, and a front lens position variable lens barrel structure in which the overall optical length is shortened at the Wide end have been proposed.

[0028]

However, the collapsible lens barrel structure and the front lens position variable lens barrel structure use a complicated mechanism such as a cylindrical cam ring or a helicoid cylinder having a cam surface formed on the end face of a helicoid. Therefore, there is a problem that the lens barrel structure becomes large and the number of parts increases, which leads to an increase in cost.

Further, a configuration having a drive source for each of the movable lens groups is also conceivable. However, for example, when there are a total of three movable lens groups, a driving source such as three motors is required. For this reason, even if the overall length can be shortened, there is a disadvantage that the projection area of the lens barrel viewed from the optical axis direction becomes large, and the layout of the camera is disadvantageous in many cases.

Also, a structure not using three motors, for example, a structure in which a cam surface is formed on the end surface of the above-mentioned helicoid cylinder and two movable lens groups are driven by this cam surface, or a cam ring is used. In this case, it is possible to drive a plurality of lens groups by using two motors to drive three movable lens groups. However, in addition to the above-described problems such as a complicated structure, a problem also arises that the projection area of the lens barrel in the optical axis direction increases.

In view of the above, the present invention provides a compact lens barrel which can drive a plurality of movable lens groups by using the driving force of one drive source and has a small overall length of the lens barrel and a small projected area in the optical axis direction. It is intended to be.

[0032]

In order to achieve the above object, according to the present invention, there is provided a first driving apparatus which is driven in a direction of an optical axis by a driving source (for example, by engaging a lead screw which is rotated by a motor). A lens holding member and a lens barrel main body or a lens barrel constituent member (for example, a fixed lens holding member) fixed to the lens barrel main body are rotatably mounted in the optical axis direction. A lens barrel is provided by providing a rotating member that is driven to rotate by the moving first lens holding member and a second lens holding member that is driven in the optical axis direction by the rotating member.

More specifically, for example, a lens barrel constituent member fixed to the lens barrel main body is arranged on the image side relative to the first lens holding member, and the second lens holding member is connected to the first holding member. When it is located closer to the subject, the rotating member is rotatably attached to the lens barrel component.

An urging means for urging the second lens holding member in one of the object direction and the image plane direction is provided, and the rotating member is moved relative to the second lens holding member in the object direction and the image plane direction. The contact may be made from the other side.

Thus, a plurality of lens holding members can be driven by one drive source without using a complicated mechanism such as using a cylindrical cam ring or a helicoid cylinder having a cam surface formed on the end surface of a helicoid. Moreover, if the portion of the rotating member that comes into contact with the second lens holding member has a cam shape, the position of the first lens holding member and the second lens holding member can be controlled so as to have different trajectories. Become.

Further, it is also possible to provide an urging means for urging the second lens holding member toward the subject, and to allow the second lens holding member to be separated from the rotating member in the image plane direction. Good.

Accordingly, the image plane side (device main body side) is placed on the lens barrel.
When an external force is applied to the rotating member, an excessive force is prevented from being applied to the rotating member, and when the external force disappears, it is possible to return to the original contact state by the urging force of the urging means. .

Further, the position of the portion of the second lens holding member that contacts the rotating member can be adjusted in the optical axis direction with respect to the main body of the second lens holding member so that the first lens holding member and the second lens holding member can be adjusted. Adjustment of the interval in the optical axis direction with the member may be performed.

The above configuration is suitable for a lens barrel having a third lens holding member driven in the optical axis direction by a driving source different from the driving source.

Thus, only two driving sources need be used for the three movable lens holding members. In particular, the first and third lens holding members are driven by engaging the lead screws driven by the respective driving sources. This makes it possible to reduce the projected area of the lens barrel in the optical axis direction as compared with the case where the lens barrel is driven by rotating the cam barrel or the helicoid barrel.

Specifically, in order from the object side, a front lens group having a convex power, a variator lens group having a concave power, a fixed afocal lens group having a convex power, and a focusing lens having a convex power In the lens barrel in which the groups are arranged, the first lens holding member holds the variator lens group, the second lens holding member holds the front lens group, and the third lens holding member holds the focusing lens group. Then, the rotating member is rotatably attached to a fixed lens holding member that holds the afocal lens group.

[0042]

1 and 2 show the construction of a zoom lens barrel suitable for carrying out the present invention and used for a photographing apparatus such as a video camera or a still picture camera and other optical equipment. I have. In these figures, 1 is a front lens group, 2 is a variator lens group, 3 is an afocal lens group, 4 is a focusing lens group, 26 is a fixed lens group, and 5 is a CCD. FIG. 1 shows the wide state.
FIG. 2 shows a telephoto state.

As is apparent from these figures, in this zoom lens barrel, not only the variator lens group and the focusing lens group but also the front lens group move in the optical axis direction in conjunction with zooming.

Reference numerals 6, 7, and 8 denote the moving trajectories of the front lens group 1, the variator lens group 2, and the focusing lens group 4 during zooming, respectively. The curve changes accordingly.

The present invention can be applied to a zoom lens barrel having no fixed lens group 26.

As described above, by moving the front lens group 1 in accordance with zooming, it is possible to shorten the entire length of the lens particularly obtained at the wide end as compared with the front lens fixed type.

(First Embodiment) FIGS. 3 to 5 show a zoom lens barrel according to a first embodiment of the present invention having the above lens configuration. FIG. 3 shows the zoom lens barrel in an optical telephoto state, and FIG. 4 shows the zoom lens barrel in an optical wide state.

In these figures, reference numeral 20 denotes a step motor main body (drive source), and reference numeral 18 denotes a lead screw which is an output shaft of a step motor having an external thread. Also, 1
Reference numeral 9 denotes a rack formed with a female screw, which is engaged with the lead screw 18. The rack 19 is attached to a variator holding frame (first lens holding member) 17 that holds the variator lens group 2. For this reason, when a driving pulse is input to the stepping motor main body 20 and the driving pulse rotates, and the lead screw 18 is rotationally driven,
The rack 19 receives a driving force in the optical axis direction from the lead screw 18, and the variator holding frame 17 to which the rack 19 is attached is driven in the optical axis direction.

An afocal holding frame (fixed lens holding member) 12 for holding the afocal lens group 3 is fixed to a lens barrel main body (consisting of a front lens barrel 10 and a rear lens barrel 15).

The afocal holding frame 12 has an extension 12b extending toward the subject in the optical axis direction.
A cam plate (rotating member) 16 is provided at the front end of the extension 12b.
Are mounted so as to be rotatable around the shaft 12a in the optical axis direction.

A long hole 16c is formed in the lower part of the cam plate 16, and the variator holding frame 17 is formed in the long hole 16c.
Is fitted with the cam follower 17a. For this reason, the variator holding frame 17 is
When the cam plate 16 moves in the optical axis direction, the cam plate 16 rotates about the shaft 12a in accordance with a change in the distance between the two. Specifically, when the variator holding frame 17 moves in a direction away from the afocal holding frame 12 (subject direction), the cam plate 16 moves counterclockwise in FIGS.
When the variator holding frame 17 moves in the direction (image plane direction) approaching the afocal holding frame 12, the cam plate 16 moves clockwise in FIGS. 3 and 4 (image plane direction).
To rotate. On the upper image surface side of the cam plate 16, the end face cam 1 is provided.
6a are formed.

A front lens holding frame (second lens holding member) 9 for holding the front lens group 1 has a sleeve portion formed long in the optical axis direction and a guide having both ends supported by lens barrel bodies 10 and 15. By slidably fitting to the bar 11,
It is held movably in the optical axis direction in the lens barrel bodies 10 and 15.

A spring 14 is disposed between the rear end of the sleeve of the front lens holding frame 9 on the guide bar 11 and the rear lens barrel 5. It is urged toward the subject.

A cam follower 9a is provided at the front end of the front lens holding frame 9 extending to the image plane side. The cam follower 9a is provided at the end of the cam plate 16 at the portion on the subject side. 16a.

For this reason, when the variator holding frame 17 moves from the state shown in FIG. 3 in the image plane direction as shown in FIG. 4 and the cam plate 16 rotates in the image plane direction, the rotating force of the cam plate 16 causes That is, when the end face cam 16a pushes the cam follower 9a, the front lens holding frame 9 is driven in the image plane direction against the urging force of the spring 14. When the variator holding frame 17 moves toward the subject from the state shown in FIG. 4 and the cam plate 16 rotates in the subject direction as shown in FIG. It is driven in the direction of the subject while being pressed against the 16 end cams 16a.

In each case, the cam follower 9
a moves along the end cam 16a.
By appropriately setting the shape of 6a, the movement locus of the front lens holding frame 9 can be made different from the movement locus of the variator holding frame 17, and a necessary movement locus of the front lens holding frame 9 can be obtained.

As described above, according to the present embodiment, different moving trajectories of the two movable lens groups (variator holding frame 17 and front lens holding frame 9) can be obtained using the driving force of the step motor body 20. Can be driven as follows. If the focusing holding frame 13 holding the focusing lens group 4 is driven by a lead screw driven by another step motor or a DC motor (not shown), the total length of the lens barrel and the projected area in the optical axis direction are reduced. It can be a small and compact lens barrel.

By the way, especially, the front lens holding frame 9 is the lens barrel main body 1.
In the telescopic state where the projection protrudes from 0 and 15 toward the subject, an external force may be applied to the front lens holding frame 9 to be pushed into the lens barrel bodies 10 and 15 as shown in FIG.

In this embodiment, the end cam 1 of the cam plate 16
6a is only in contact with the portion of the front follower holding frame 9 on the object side of the cam follower 9a, so that the external force acts on the front follower holding frame 9 (when the external force is greater than the biasing force of the spring 14). ), Cam follower 9 from end face cam 16a
a is allowed, and the front lens holding frame 9 is allowed to separate from the cam plate 16 in the image plane direction. Therefore, damage to the cam plate 16 and the cam follower 9a due to external force is prevented. Therefore, it is not necessary to increase the strength of the cam plate 16 and the cam follower 9 in consideration of the damage due to external force, which is effective for making the cam plate 16 and the cam follower 9a, and thus the entire lens barrel compact.

When the front lens holding frame 9 is pushed to some extent by the above-mentioned external force, its end face 9b comes into contact with the end face of the extension of the afocal holding frame 12 toward the subject, so that the front lens holding frame 9 is pressed. Is prevented from being pushed further.

When the external force disappears, the front lens holding frame 9 is moved to its original position by the urging force of the spring 14, and the cam follower 9
a returns to the position where it contacts the end cam 16a.

(Second Embodiment) In the first embodiment,
Although the case where the cam follower 9a is provided integrally with the main body of the front lens holding frame 9 has been described, in the present embodiment, as shown in FIGS. The cam follower portion 22a
The cam follower block 22 provided with is mounted so that the position can be adjusted in the optical axis direction by the screw 23, that is, the position of the cam follower portion 22a in the optical axis direction can be adjusted.

More specifically, a long hole 22b extending in the optical axis direction is formed in the center of the cam follower block 22, and a screw 23 is inserted into the long hole 22b to form a lower hole formed in the extended portion of the front lens holding frame 21. The cam follower block 22 is supported by screwing the cam follower block 22c.

When adjusting the position of the cam follower block 22, the screw 23 is slightly loosened, an eccentric tool (not shown) is passed through the adjustment hole 22 c formed in the cam follower block 22, and the extension of the front lens holding frame 21 is performed. It is positioned in the eccentric tool hole 21d formed in the protruding portion. Then, by rotating the eccentric tool, the cam follower block 22 may be slightly moved in the optical axis direction to adjust the position, and the screw 23 may be tightened again.

As described above, the position of the cam follower 22a formed separately from the main body of the front lens holding frame 21 can be adjusted in the optical axis direction, so that the front lens holding frame 21 and the variator holding frame can be adjusted. 17 can be adjusted.

In each of the above embodiments, the case where the variator holding frame and the front lens holding frame are combined and driven by one motor has been described. However, the present invention is applicable to other combinations of lens holding members. The same can be applied.

The movement of the lens holding member (variator holding frame in the above embodiment) driven directly by the motor causes the other plurality of lens holding members to rotate (cam plate).
May be driven.

Further, in each of the above embodiments, the case where the rotating member is attached to the lens holding member (afocal holding frame) fixed to the lens barrel main body has been described. You may make it attach as possible.

[0069]

As described above, according to the present invention,
When the first lens holding member is driven by the driving source (for example, by engaging with a lead screw rotated by the driving source), the movement of the first lens holding member causes the rotating member to face the optical axis direction. Since the second lens holding member is driven by the rotating member, a complicated mechanism such as using a cylindrical cam ring or a helicoid cylinder having a cam surface formed on the end surface of the helicoid is used. It is possible to drive a plurality of lens holding members by one drive source without the need for the above. In addition, if the portion of the rotating member that comes into contact with the second lens holding member has a cam shape,
The position of the first lens holding member and the second lens holding member can be controlled so as to have different trajectories.

Further, if an urging means for urging the second lens holding member toward the subject is provided, the second lens holding member can be separated from the rotating member in the image plane direction. When an external force that pushes the lens barrel toward the image plane side (apparatus body side) is applied, it prevents an excessive force from being applied to the rotating member, and when the external force disappears, the original force is applied by the urging force of the urging means. It can be returned to the contact state.

Further, if the position of the second lens holding member that contacts the rotating member can be adjusted in the optical axis direction with respect to the main body of the second lens holding member, the first lens holding member and the second lens holding member can be adjusted. The distance between the lens holding member and the lens holding member can be adjusted in the optical axis direction.

The invention described above is effective in reducing the size of a lens barrel having a third lens holding member driven in the optical axis direction by a driving source different from the driving source.
That is, it is only necessary to use two driving sources for the three movable lens holding members, and in particular, the first and third lens holding members are driven by engaging the lead screws driven by the respective driving sources. By doing so, the projection area in the optical axis direction of the lens barrel can be reduced as compared with the case where the lens barrel is driven by rotating the cam barrel or the helicoid barrel.

In particular, according to the present invention, in order from the object side, a front lens group having a convex power, a variator lens group having a concave power, a fixed afocal lens group having a convex power, and a focusing lens having a convex power The first lens holding member holds the variator lens group, the second lens holding member holds the front lens group, and the third lens holding member holds the focusing lens group. By holding, it is possible to achieve overall compactness by shortening the entire length of the lens barrel and reducing the projected area in the optical axis direction.

[Brief description of the drawings]

FIG. 1 is a diagram showing a lens arrangement (wide state) and a zoom operation of a zoom lens barrel suitable for carrying out the present invention.

FIG. 2 is a diagram showing a lens arrangement (telephoto state) and a zoom operation of a zoom lens barrel suitable for carrying out the present invention.

FIG. 3 is a sectional view of a lens barrel (telephoto state) according to the first embodiment of the present invention.

FIG. 4 is a lens barrel (wide state) of the first embodiment.
FIG.

FIG. 5 is an explanatory diagram showing an operation when the lens barrel of the first embodiment receives an external force.

FIG. 6 is a configuration diagram around a front lens in a lens barrel according to a second embodiment of the present invention.

FIG. 7 is an exploded view around a front lens in the second embodiment.

FIG. 8 is a configuration diagram of a conventional lens barrel.

FIG. 9 is an electric circuit block diagram of a conventional lens barrel.

[Explanation of symbols]

 1. front lens group 2. variator lens group 3. afocal lens group 4. focusing lens group 5. CCD 6, 7, 8, lens movement locus during zoom 9, 21, front lens Holding frame 10, 15 ··· Barrel body 11 ··· Guide bar 12 ··· Afocal holding frame 13 ··· Focusing holding frame 14 ··· Spring 17 ··· Variator holding frame 18 ··· Lead screw 19 ··· Rack 20 ··· Step motor body 22 Cam follower block

Claims (13)

[Claims] 1. A first device driven in a direction of an optical axis by a driving source.
A lens holding member and the first lens holding member which is rotatably mounted in the optical axis direction on the lens barrel main body or a lens barrel constituting member fixed to the lens barrel main body and moves in the optical axis direction. A lens barrel comprising: a rotating member that is driven to rotate; and a second lens holding member that is driven in the optical axis direction by the rotating member that rotates. 2. The lens according to claim 1, wherein the first lens holding member is driven in the optical axis direction by engaging with a lead screw that is rotationally driven by a motor as the driving source. Lens barrel. 3. A lens barrel constituent member fixed to a lens barrel main body is disposed closer to the image plane side than the first lens holding member, and the second lens holding member is positioned more than the first holding member. 3. The lens barrel according to claim 1, wherein the lens barrel is arranged on a subject side, and the rotating member is rotatably attached to the lens barrel constituent member. 4. 4. The lens barrel according to claim 1, wherein the lens barrel constituting member is a lens holding member fixed to the lens barrel body. 5. An image forming apparatus comprising: urging means for urging the second lens holding member in one of a subject direction and an image plane direction; The lens barrel according to any one of claims 1 to 4, wherein the lens barrel abuts from the other side in the direction and the image plane direction. 6. The lens barrel according to claim 1, wherein a portion of the rotating member that contacts the second lens holding member is formed in a cam shape. 7. An image forming apparatus, comprising: urging means for urging the second lens holding member toward a subject, so as to allow the second lens holding member to be separated from the rotating member in an image plane direction. The lens barrel according to any one of claims 1 to 6, wherein: 8. A portion of the second lens holding member that comes into contact with the rotating member can be adjusted in the optical axis direction with respect to a main body of the second lens holding member. Item 8. The lens barrel according to any one of Items 1 to 7. 9. The lens barrel according to claim 1, further comprising a third lens holding member driven in a direction of an optical axis by a driving source different from the driving source. 10. The lens mirror according to claim 9, wherein the third lens holding member is driven in the optical axis direction by engaging with a lead screw that is rotationally driven by the another driving source. Tube. 11. A front lens group having a convex power, a variator lens group having a concave power, a fixed afocal lens group having a convex power, in order from the object side.
A focusing lens group having a convex power is disposed, the first lens holding member holds the variator lens group, the second lens holding member holds the front lens group, and the third lens holding The lens barrel according to claim 1, wherein a member holds the focusing lens group. 12. The lens barrel according to claim 11, wherein the rotating member is rotatably attached to a fixed lens holding member that holds the afocal lens group. 13. An optical apparatus comprising the lens barrel according to claim 1. Description: