JPH11271829A - Optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a device with simple configuration without impairing the optical performance of a variable power optical system. SOLUTION: This device is provided with the variable power optical system, 1st guiding means 5 and 6 guiding the variable power optical system by rotation for the purpose of variable power operation, 2nd guiding means 36a and 37a guiding the 1st guiding means and the variable power optical system from a withdrawing position to an extending position without the rotation of the 1st guiding means, and an actuation means 8 rotating the 1st guiding means guided to the extending position by the 2nd guiding means and moving the variable power optical system for the purpose of the variable power operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical device having a zoom function.

[0002]

2. Description of the Related Art Conventionally, for example, in a small-sized zoom camera, as shown in FIG.
1 and a straight cam 202 to adjust the position to perform zooming. At the time of collapsing, the cam ring 201 is further rotated from the WIDE position until the front end of the lens barrel 203 shown in the WIDE state in FIG.
It has a structure that collapses.

[0003]

The above-mentioned prior art has the following problems. (I) Due to the configuration of the cam ring that regulates the position of the photographing optical systems in the front and rear groups, the photographing optical system is retracted in a WIDE state, that is, in a state in which the interval between the front group and the rear group is widened. Camera thickness increases. (Ii) In order to eliminate the disadvantage of (i) above, in order to reduce the distance between the front and rear lens groups during collapsing, as shown in FIG. 14, the WIDE end of the cam groove 301 for regulating the position of the rear lens group (in the figure) 3
When the notch portion 301a is provided on the extension of the (01b portion) to reduce the thickness of the camera at the time of collapsing, even if the lens interval between the front and rear groups is narrowed as shown in FIG. Since there is no change in the length of the cam ring, the thickness of the camera at the time of collapsing depends on the length of the cam ring, and as a result, it is not so different from the case (i).

An object of the present invention is to provide an optical device which can be reduced in size with a simple configuration without impairing the optical performance of a variable power optical system.

[0005]

In order to achieve the above object, the present invention provides a variable power optical system, first guiding means for guiding the variable power optical system for a variable power operation by rotation, and Second guide means for guiding the first guide means and the variable power optical system from the retracted position to the extended position without rotating the first guide means; and An actuating means for rotating the guided first guiding means and moving the zoom optical system for a zooming operation.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of the present invention will be described below with reference to FIGS. 1 to 9 of the accompanying drawings.

FIG. 1 is an exploded perspective view of a zoom lens barrel provided in a camera as an optical device according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a first-group barrel holding a first-group lens (not shown) at a distal end portion 1a;
Cam ring rotatably fitted on the inner peripheral surface of
Denotes a shutter base plate that holds a second group lens (not shown) and a known shutter unit, 4 denotes a third group holder that holds a third group lens, and 5 denotes the first group lens and the first lens barrel. A first group cam ring 6 for defining a position in the photographing optical axis direction is rotatably fitted to the outer peripheral surface of the first group cam ring 5 and moves the first group lens barrel 1 linearly only in the photographing optical axis direction. Linear guide in which an axial groove 6a is formed on the inner peripheral surface.

An internal gear (not shown) is mounted on the inner peripheral surface of the rear end 5a of the first group cam ring 5, and the internal gear engages with a gear 7 shown. The gear 8 which receives power from a known drive source is engaged. The first group cam ring 5 is rotatably held on the inner peripheral surface of the aforementioned linear guide 6, and a pin 9 protruding from the outer peripheral surface of the ring 5 is provided with a circumferential groove 6 of the aforementioned linear guide 6.
b, the group cam ring 5 cannot move in the optical axis direction.

On the other hand, a pin 10 is also protruded from the outer peripheral surface of the first lens barrel 1. The pin 10 is inserted into the cam groove 5b of the cam ring 5 so as to be relatively slidable. The first lens barrel 1 is also slidably inserted into the axial groove 6a, so that the position of the first lens barrel 1 in the optical axis direction is controlled by the cam groove 5b.

When the gear 8 starts rotating by receiving the power from a drive source (not shown), the gear 7 rotates, and this rotating force is transmitted to the internal gear of the cam ring 5 so that the cam ring 5 starts rotating. Since the pin 10 implanted in the first lens barrel 1 is relatively slidable in the cam groove 5b and the axial groove 6a, when the cam ring 5 rotates, the first group mirror is displaced by the amount of displacement of the cam groove 5b in the optical axis direction. The cylinder 1 is driven in the direction of the optical axis, and as a result, zooming movement of the first group lens is performed.

Next, the zooming mechanism and operation of the second group lens will be described. The second-group cam ring 2 is rotatably held on the inner peripheral surface of the first-group barrel 1, and the pin 11 implanted at the rear end 2 a is slidably inserted into the circumferential groove 1 b of the first-group barrel 1. At the same time, the cam ring 5 is relatively slidably inserted into the groove 5c in the optical axis direction.

Therefore, when the cam ring 5 starts to rotate,
Although the first lens barrel 1 moves along the optical axis, the movement of the second group cam ring 2 in the optical axis direction is prohibited by the implantation pin 11 and by the circumferential groove 1b of the first lens barrel 1. The cam ring 2 moves in the optical axis direction integrally with the first lens barrel 1. Further, since the movement of the implantation pin 11 in the direction of rotation thereof is prohibited with respect to the cam ring 5 by the groove 5c of the cam ring 5, when the cam ring 5 rotates, the second group cam ring 2 is integrated with the first group lens barrel 1 and the optical axis. , And at the same time, rotate at the same angle as the cam ring 5.

The first lens barrel 1 has two guide bars 12 and 13 fixed inside thereof in parallel with the optical axis.
One guide bar 12 is slidably inserted into the hole 3a of the shutter base plate 3, and a compression spring 14 fitted in the guide bar 12 moves the shutter base plate 3 rearward parallel to the optical axis (to the right in FIG. 1). Is energizing. The other guide bar 1
Reference numeral 3 is fitted in a notch groove 3b on the outer peripheral edge of the shutter base plate 3, so that the base plate 3 does not rotate around the optical axis. Therefore, the base plate 3 can only move parallel to the optical axis.

The shutter base plate 3 includes a shutter blade 3
The shutter base plate 3 includes a stepping motor 190 for driving a third group lens and a motor SM for driving a shutter blade, which will be described later, together with components such as 2 and 33, a blade presser 34, and the like. Installed.

The shutter base plate 3 also includes a planting pin 3
The pin 3c is engaged with the cam surface 2b of the second group cam ring 2 described above.

Since the shutter base plate 3 is urged backward along the optical axis direction by the compression spring 14, the pin 3 c is attached to the cam surface 2 b of the second group cam ring 2.
It is pressed by the force of. Accordingly, when the cam ring 5 is rotated, the second group cam ring 2 is also rotated as described above, and the shutter base plate 3 holding the second group lens is moved in the optical axis direction by the cam surface 2b, so that the second group cam ring 2 is rotated. A zooming operation of the group lens occurs.

As described above, since the shutter base plate 3 can move in the forward direction of the optical axis against the force of the compression spring 14, the shutter base plate 3 is moved parallel to the optical axis when retracted. The distance between the first lens unit and the second lens unit can be reduced by moving the lens unit forward.

Next, the movement mechanism and operation of the third group lens will be described. Third group guide bars 15 and 16 are fixed to the third group holder 4 holding the third group lens so as to be parallel to the optical axis at symmetrical positions with respect to the optical axis.

A compression spring 17 is fitted around one guide bar 15 at its outer periphery, and is slidably fitted into a hole 3c 'of the shutter base plate 3. The spring 17 urges the third group holder 4 backward in the optical axis direction, and plays a role of reducing backlash in a threaded portion between a helicoid shaft 18 and a female helicoid cylinder described later and backlash in a reduction gear train. I have.

The other guide bar 16 is engaged with the cutout groove 3d of the base plate 3 so that the holder 4 does not rotate around the optical axis. Further, the holder 4 is provided with a helicoid shaft 18 projecting in parallel with the guide bars 15 and 16.
Is screwed into a female helicoid cylinder integrated with the gear 19, so that the third group holder 4 can be moved in the optical axis direction by rotating the gear 19.

Reference numeral 190 denotes a known stepping motor having a permanent magnet rotor 20 polarized in four poles in the circumferential direction. FIG. 2 is a front view of the motor. The yokes 21 and 23 form one magnetic path with the bobbin 25, and the yokes 22 and 24 form one magnetic path with the bobbin 26.

Reference numeral 27 denotes a magnet cover having a fitting hole 27a for rotatably positioning the upper end of a central shaft 28 fixed to the permanent magnet rotor 20. The other end 28a of the center shaft 28 is rotatably held by a through hole 3e provided in the shutter base plate 3, and is supported between the above-described magnet cover 27 and the center cover 28. Further, the shaft end 28a protrudes to the back side of the shutter base plate 3, and a pinion 29 for transmitting the output is fixed to the tip end.

In the stepping motor constructed as described above, the coils wound on the bobbins 25 and 26 are energized to excite the yokes 21 to 24, and the phase of the energization is appropriately switched to permanently set the energization. The magnet rotor 20 rotates, and its output is transmitted to the pinion 29. When the pinion 29 starts rotating, the reduction gear train 30 sequentially rotates, and the gear 19 integrated with the female helicoid cylinder starts rotating. By this rotation, the helicoid shaft 18 is driven in the optical axis direction, and the third group holder 4 is moved in the optical axis direction, that is, zooming of the third lens group is performed.

In this embodiment, since a rear focus type photographing lens in which focus correction, that is, AF (autofocus) is performed by the third group lens is configured, the third group lens is used in addition to the above-described zooming operation. Lens position control for focus correction is also performed. Note that the driving principle is the same as in the above-described case, and a description thereof will be omitted.

Reference numeral 35 denotes a gear supporting plate fixed to the rear end of the linear guide 6. The rotating shaft 35a for rotatably supporting the gear 7 and the gear 8 are rotatably supported on the gear supporting plate 35. A rotating shaft 35b is protruded, and a screw hole screwed to a helicoid shaft 36a described later, that is, a female helicoid hole 35c and a female helicoid hole 35d screwed to the helicoid shaft 37a penetrate in parallel with the optical axis. . The positions of the female helicoid holes 35c and 35d are located on a circumference having a diameter smaller than the outer diameter of the lens barrel 1, and the helicoid shafts 36a and 36d screwed into the female helicoid holes 35c and 35d.
7a, the holes 35c and 3 so that they do not collide with other members.
The position of 5d is determined. Reference numeral 35e denotes a stopper pin that collides with the shutter base plate 3.

A fixed lens barrel 38 is fixed to a camera body 39. The rectilinear guide 6 is inserted into the fixed lens barrel 38 and is movable in the front-rear direction in parallel with the optical axis. As shown in FIG. 3, the rectilinear guide 6 includes the first group cam ring 5, the first group barrel 1, and the second group. A cam ring 2 is fitted in this order from the outside to the inside, and a shutter unit 31 including a shutter base plate 3 is provided inside the second group cam ring 2.
The third group holder 4 is disposed behind the shutter unit 31, and a gear carrying plate 35 attached to the rear end of the linear guide 6 is disposed.

The linear guide 6, the first group cam ring 5, the first group lens barrel 1, the second group cam ring 2, the shutter unit 31, the third group holder 4, and the gear holding plate 35 can be moved along the optical axis in the fixed lens barrel 38. The unit composed of these seven main members is referred to as a photographing lens barrel unit in this specification.

An axial ridge 6f is provided on the outer peripheral surface of the linear guide 6.
The projection 6f is fitted in an axial groove (not shown) formed in the inner peripheral surface of the fixed lens barrel 38 so as to be relatively slidable. Can move along the axial direction in the fixed lens barrel 38 without rotating.

A large-diameter portion 6g is formed at the rear end of the rectilinear guide 6, and the outer peripheral surface of the large-diameter portion 6g is rotated by a later-described bayonet ring 43 to position the photographing lens barrel unit in the optical axis direction. 6c and 6d and 6
e (see FIG. 6), and the projections 6c and 6c
d and 6e are adapted to engage with a bayonet ring 43 described later.

The gear carrier plate 3 is provided inside the camera body 39.
And a power transmission mechanism for rotating the bayonet ring 43, and a power transmission mechanism for transmitting a driving force for rotating the gear 8. And a mechanism are accommodated. These power transmission mechanisms include a ring gear 40 shown in FIG. 1 and two gears 36 meshing with the internal teeth of the ring gear 40.
And 37, helicoid shafts 36a and 37a formed integrally with the gears 36 and 37, a bayonet ring 43 having a gear portion 43d formed on a part of the outer peripheral surface, and the like.

The structure of the power transmission mechanism will be described below with reference to FIGS. As shown in FIG. 1, the camera body 39 is provided with a hole 39c capable of accommodating the above-mentioned photographing lens barrel unit, and the innermost end face of the hole 39c is, as shown in FIG. A gear support shaft 39a that fits into the concave portion of the end surface of the gear 36 and a gear support shaft 39b that fits into the concave portion of the end surface of the gear 37 protrude, and the gear 39 rotates at a fixed position by the shaft 39a. The gear 37 is rotatably supported at a fixed position by the shaft 39b.

The gear 36 and the gear 37 are gears with a screw shaft formed integrally with the helicoid shaft 36a and the halicoid shaft 37a, respectively. And
The helicoid shaft 37a is screwed into a female helicoid hole 35d (screw hole) of the gear holding plate 35.

Ring gear 4 meshing with gears 36 and 37
Reference numeral 0 denotes a gear in which external teeth 40a are formed on the outer peripheral surface and internal teeth 40b are formed on the inner peripheral surface, and the gears 36 and 37 mesh with the internal teeth 40b of the gear 40.

As shown in FIG. 3, the ring gear 40 is rotatably disposed at the innermost position of the taking lens barrel unit housing hole 39c of the camera body 39.
The gears 36 and 37 are engaged with the internal teeth 40 b of the ring gear 40, and the gears 48 and 37 are engaged with the external teeth 40 a of the ring gear 40.
Are engaged. The gear 48 protrudes outward from a window opened on the upper surface of the camera body 39, and a gear (not shown) rotated by a drive source (not shown) is meshed with the gear 48.

In order not to move the ring gear 40 and the gears 36 and 37 in the axial direction, a gear holding plate 41 having a hole 41a for loosely fitting to the helicoid shaft 36a and a hole 42a for loosely fitting to the helicoid shaft 37a are provided. Gear holding plate 42
Are fitted to the helicoid shafts 36a and 37a, respectively, and the holding plates 41 and 42 are arranged facing the end faces of the gears 36 and 37 and the ring gear 40, and the holding plates 41 and 42 are screwed to the camera body 39. And so on.

A counterbore portion 39d is formed at the opening edge of the hole 39c of the camera body 39, and the counterbore portion 39d is formed.
, The bayonet ring 43 is rotatably disposed. A part of the outer peripheral surface of the bayonet ring 43 includes a gear portion 4.
3d is formed, and a gear 47 for rotating the bayonet ring 43 is engaged with the gear portion 43d.

The bayonet ring 43 has three steps 4
3a, 43b, 43c are formed, and bayonet ring holding plates 44 to 46 having spring-like contact pieces are engaged with each step so as not to move the bayonet ring 43 in the axial direction. The plates 44 to 46 are fastened to the end face of the camera body 39 with screws or the like. The installation positions of these bayonet ring holding plates 44 to 46 correspond to the three projections 6c, 6d, 6e of the straight guide 6.

Next, the operation of each part when the taking lens barrel unit is extended forward from the retracted position (the state shown in the lower half of FIG. 3) in the above-described configuration will be described.

When the gear 48 is rotated by a drive source (not shown), the ring gear 40 is rotated, and the gears 36 and 37 meshing with the gear 40 are rotated in the same direction and the same rotation angle, respectively. For this reason, the heicoid shafts 36a and 37a integral with the gears 36 and 37 are rotated, and
The gear carrying plate 35 screwed to 6a and 37a is moved forward parallel to the optical axis. Accordingly, the rectilinear guide 6 integrated with the gear holding plate 35 advances in the fixed barrel 38, and the first group cam ring 5, the first group barrel 1, the second group cam ring 2, the shutter unit 31, and the third group cam ring 5 accommodated in the rectilinear guide 6 are provided. The group holder 4 moves forward integrally with the rectilinear guide 6.

At this time, the linear guide 6 moves forward with the ridge 6f projecting from the outer peripheral surface of the linear guide 6 fitted in the axial groove of the inner peripheral surface of the fixed lens barrel 38. It does not rotate.

In the course of the forward movement, the interval between the first lens barrel 1 and the shutter base plate 3 is widened by the action of the spring 14 on the guide bar 12 provided in the second group cam ring 2, so that the first group lens The distance from the second group lens also gradually increases. After the projection pin 35e of the gear holding plate 35 abuts against the rear surface of the shutter base plate 3, the third group holder 4 separates from the holding plate 41, and the distance between the first group lens and the second group lens remains constant. , The lens barrel unit is extended from the fixed lens barrel 38.

When the extension of the lens barrel unit approaches the end, the lens barrel unit reaches a position passing through the bayonet ring 43, and the large diameter portion 6 g at the rear end of the linear guide 6 is inserted into the hole 38 a of the fixed lens barrel 38. The straight guide 6 is fitted in the fixed lens barrel 38 and supported by the large-diameter portion 6g. FIG. 5 shows the state at this time.

When the power supply for extending the lens barrel unit is cut off (that is, when the rotation of the gear 48 stops), the unit stops.

At this time, the bayonet ring holding plates 44, 4
Reference numerals 5 and 46 denote three projections 6c, 6d and 6e of the linear guide 6.
Should return to the rear of the optical axis. However, the stepped portion 43 as shown in FIG. 1 is provided at the portion of the bayonet ring 43 corresponding to the projections 6c, 6d, and 6e.
a, 43b, and 43c, the bayonet ring holding plate is locked by the stepped portion, and the lens barrel unit is positioned at the rear end of the bayonet ring 43, that is, the bayonet ring 43 shown in FIG. When the rear end of the unit is positioned further forward than the front end of the unit, the operation stops.

In this state, power from a drive source (not shown) is transmitted to the gear 47, and the gear 47 starts rotating clockwise.

Accordingly, the bayonet ring 43 starts to rotate counterclockwise. When the bayonet ring 43 rotates, the steps 43a, 43b, 43c, which have been locked by the spring force of the bayonet ring holding plates 44, 45, 46, also rotate, so that the locking is released, and the bayonet ring holding plate is released. 44, 45, 46 are projections 6c, 6d,
6e starts to generate a force to push the optical axis 6e backward. However, at this time, since the bayonet ring 43 has already been rotated by a certain angle, the projections 6c, 6d, 6e of the rectilinear guide 6 are pressed against the bayonet ring portions 43e, 43f, 43g by the pressing force.

When the rotation of the bayonet ring 43 continues, the projections 6c, 6d and 6e of the rectilinear guide 6 are pushed by the cams by the cut-and-raised cams 43h, 43i and 43j provided on the bayonet ring. Then, the unit is extended further forward of the optical axis by overcoming the pressing force.

Thereafter, the projections 6c, 6d, 6e are connected to the cam surfaces 43h, 43i, 43 of the bayonet ring 43.
a flat portion 43 provided on an extension of j and parallel to the front end surface
When the vehicle rides on k, 43l, 43m, the power from the drive source is shut off.

FIG. 7 is a front view of a main part in a state where the above-mentioned movement has been completed. In this state, the lens barrel unit is completely extended from the retracted position and is firmly locked at the photographing standby position. The state inside the lens barrel at this time is shown in FIG.
Is shown in the upper half.

FIGS. 8 and 9 illustrate a state in which the gear 8 for rotating the cam ring 5 and the gear 50 for rotating by receiving the power from a drive source (not shown) are connected by the above-described retracting operation from the retracted position. It is a principal part sectional view for performing.

FIG. 8 shows a state in which the gear 8 is being fed out of the retracted position. In this state, the gear 8 and the gear 50 are not connected. Thereafter, when the lens barrel unit is further extended and the gear 8 and the gear 50 are connected as shown in FIG. 9, the mirror is moved in a state where the teeth of the gear 8 and the gear 50 do not interfere with each other. When the cylinder unit is extended (that is, when the gear 8 and the gear 50 are properly engaged), the gear 50 stands by at the position shown by the solid line under the urging force of the coil spring 49, and is connected to the gear 8. .

However, when the teeth of the gear 8 and the teeth of the gear 50 interfere with each other due to the extension of the lens barrel unit (that is, the teeth of the gear 8 and the teeth of the gear 50 collide), the gear 50 is attached to the camera body 39. While being held rotatably by the protruded shaft 39e, it retreats to the position shown by the one-dot chain line in FIG. 9 against the urging force of the coil spring 49. The driving force from a driving source (not shown) is transmitted even when the gear 50 is retracted (for example, the tooth thickness is set so that the driving-side gear (not shown) can mesh with the gear 50 even at the retracted position. When the gear 50 rotates to a position where the gear 50 can engage with the gear 8 by receiving the power from the drive source, the gear 50 slides to the position shown by the solid line in FIG. Then, connection with the gear 8 is performed.

In the state where the extension from the retracted position is completed, the first, second and third lens units are not at the photographing position, and thereafter, the camera rotates the cam ring 5 by a certain angle by the aforementioned driving means. Let it. Then, the first group lens is extended to the WIDE photographing position shown below the optical axis in FIG. Therefore, the distance between the first lens group and the second lens group is further increased by the action of the compression spring 14,
In the second group lens, the planting pin 3c of the shutter base plate 3 abuts on the cam surface 2b of the second group cam ring 2, and is held at the WIDE photographing position similarly to the first group lens. The lower part of the optical axis in FIG. 4 shows a cross section of the main part of the taking lens unit at this time. In addition, the upper side of the optical axis in FIG. 4 is a state in which the extension of the lens barrel unit from the retracted position is completed.
This is the same as the state shown on the upper side of the optical axis.

After rotating the cam ring 5 to the above state, the third group lens is driven to an appropriate position by the stepping motor unit 190 as described above, and the photographing lens system completes the preparation for WIDE photographing. The cross section of the main part of the taking lens unit at this time is shown above the optical axis in FIG. The lower side of the optical axis in FIG. 5 shows a state in which the photographing lens system is arranged at the TELE position by zooming, but the zooming operation has been described in detail earlier, and thus will be omitted.

Further, when the lens barrel unit is retracted from the extended state, the movement of each part in the above-described extension from the retracted state is simply reversed, so that the details thereof are omitted.

(Second Embodiment) In the first embodiment described above, the taking lens barrel unit is extended by a driving member, and the bayonet ring 43 and the bayonet ring holding plates 44, 45, and 46 are used to connect the unit. The camera body 39 is held as shown in FIG.
The linear guide 6 including the lens barrel unit whose outer shape is guided and extended by the hole 39c is rotated clockwise in FIG. 10 from the extended position by a known driving means, and as shown in FIG. The object of the present invention is attained even if the configuration is such that 6d and 6e are respectively held between the holding plates 44, 45 and 46 and the camera body 39.

At this time, the gear carrier plate 35 cannot be rotated due to the helicoid coupling with the helicoid shafts 36a and 37a, but the gear carrier plate 35 is held rotatably with respect to the rectilinear guide 6. Needless to say.

(Third Embodiment) Further, as shown in FIG. 12, the projections 6c, 6d, 6e of the linear guide 6 are connected to 151a, 151b, 151c as shown in FIG.
The member 151 is rotatably held on the rectilinear guide 6, and after the feeding from the retracted position is completed, the ring 151 is rotated. As described above, the configuration may be such that 151a, 151b, 151c are engaged and held between the bayonet ring holding plates 44, 45, 46 and the camera body 39.

(Correspondence of Claims and Embodiments) In the above embodiments, the first lens group, the second lens group, and the third lens group correspond to the variable power optical system described in the claims. , The group cam ring 5 and the rectilinear guide 6 are provided to the first guide means described in the claims, and a drive source (not shown) for transmitting the driving force to the gear 8 is provided to the actuating means described in the claims. 6 protruding from the outer peripheral surface of the shaft 6
An axial groove (not shown) formed on the inner peripheral surface of the fixed lens barrel 38 and the helicoid shafts 36a and 37a respectively correspond to the second guide means described in the claims.

[0060]

As described above, according to the present invention,
It is possible to provide an optical device that can achieve miniaturization with a simple configuration without impairing the optical performance of a variable power optical system.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a lens barrel of a camera according to a first embodiment of the present invention.

FIG. 2 is a front view of a stepping motor mounted in the lens barrel.

FIG. 3 is a cross-sectional view of the lens barrel.

FIG. 4 is a cross-sectional view of the lens barrel.

FIG. 5 is a sectional view of the lens barrel.

FIG. 6 is a view for explaining collapse and extension of the lens barrel.

FIG. 7 is a diagram for explaining collapse and extension of the lens barrel.

FIG. 8 is an explanatory diagram of a power transmission mechanism in the lens barrel.

FIG. 9 is an explanatory diagram of a power transmission mechanism in the lens barrel.

FIG. 10 is an explanatory diagram of a second embodiment of the present invention.

FIG. 11 is an explanatory view of the second embodiment.

FIG. 12 is an explanatory view of a third embodiment of the present invention.

FIG. 13 is an explanatory view of a retractable mechanism of a conventional zoom camera.

FIG. 14 is an explanatory diagram of a retractable mechanism of a conventional zoom camera.

FIG. 15 is an explanatory diagram of a retractable mechanism of a conventional zoom camera. REFERENCE SIGNS LIST 1 first lens barrel 2 second group cam ring 3 shutter base plate 4 third group holder 5 first group cam ring 6 linear guide 7 gear 8 gear 9-11 planting pin 12,13 guide bar 15,16 guide bar 18 helicoid shaft 35 gear holding plate 35a, 35b Fixed shaft 35c, 35d Helicoid hole 36a, 37a Helicoid shaft 36, 37 Gear 38 Fixed lens barrel 39 Camera body 40 Ring gear 43 Bayonet ring

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] February 10, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0059

[Correction method] Change

[Correction contents]

(Correspondence of Claims and Embodiments) In the above embodiments, the first lens group, the second lens group, and the third lens group correspond to the variable power optical system described in the claims. The first group cam ring 5 and the linear guide 6 are attached to the first guide means described in the claims, and the inner periphery of the fixed lens barrel 38 fitted to the axial ridge 6f protruding from the outer peripheral surface of the linear guide 6. Not-shown axial groove, helicoid shaft 36
a and 37a correspond to the second guide means described in the claims, and a drive source (not shown) for transmitting a driving force to the gear 8 corresponds to the actuation means described in the claims. An axial groove (not shown) engraved on the inner peripheral surface of the fixed lens barrel 38 fitted to the protruding axial ridge 6f is provided on the guide portion described in the claims, and the helicoid shafts 36a and 37a are provided on the guide portion. The gears 8 and 50 correspond to the driving force transmitting means described in the claims, and the coil spring 49 corresponds to the elastic means described in the claims. Further, a drive source (not shown) for transmitting a driving force to the gear 48 is provided to the driving means according to the second aspect, a bayonet ring 43 is provided to the positioning means according to the eighth aspect, and a drive source for transmitting the driving force to the gear 47 is not shown. The driving source is the driving means of claim 9, the camera body 39 is the positioning means of claim 10, the projections 151a, 151b, 151c are the moving means of claim 10, the projections 151a, 151b, and Driving means (not shown) for rotating the motor 151 c corresponds to the driving means according to claim 11.

Claims (1)

[Claims] 1. A variable power optical system, first guide means for guiding the variable power optical system for a variable power operation by rotation, and the first guide means without rotation of the first guide means. A second guide for guiding the guide means and the variable power optical system from the retracted position to the extended position, and rotating the first guide means guided to the extended position by the second guide means, Operating means for moving the magnification optical system for zooming operation.