JP2005195812A - Lens driving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens driving device having high lens moving accuracy and securing sufficient driving force even by a compact driving source. <P>SOLUTION: In the lens driving device 1, an electromagnetic mechanism 3 is constituted around moving lens bodies 20 and 30. The lens driving device 1 includes a speed reduction mechanism 5 for decelerating and transmitting the rotation of the rotor of the mechanism 3 and a conversion mechanism 7 for converting the rotation transmitted through the mechanism 5 into the driving force in a direction going along an optical axis L and directly operating the lens bodies 20 and 30 between the mechanism 3 and the lens bodies 20 and 30. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a lens driving device used for a camera or the like.

  A thin camera mounted on a portable device with a camera has a shorter lens moving distance for performing focus adjustment and zoom adjustment at the time of shooting than a normal camera. It is used.

Examples of such a magnetic drive type lens drive device include a lens holder that holds a lens, a ring-shaped magnet attached to the outer periphery of the lens holder, and a drive coil facing the magnet. By controlling energization to the coil, a configuration has been devised in which the lens is directly moved in the optical axis direction without using a conversion mechanism, and the lens is magnetically held therein (for example, Patent Documents). 1).
JP-A-10-150759

  However, the lens driving device disclosed in Patent Document 1 has a problem in that since the cam drive resolution with respect to the lens is not sufficient, the lens stop position cannot be made fine, and as a result, the lens movement accuracy is low.

  Further, since a thin camera mounted on a camera-equipped portable device is required to be small and consume less power, only a small drive can be mounted as a drive source. For this reason, for example, when two lenses are driven by a common driving source, there is a problem that the driving force is insufficient.

  In view of the above problems, an object of the present invention is to provide a lens driving device that has high lens movement accuracy and can ensure a sufficient driving force even with a small driving source.

  In order to solve the above-described problems, in the present invention, in the lens driving device including a moving lens body including a lens and a driving unit that moves the moving lens body along the optical axis of the lens, the driving unit includes: An electromagnetic mechanism provided with a rotor arranged to surround the moving lens body on the outer peripheral side and rotating around the optical axis, a reduction mechanism for reducing and transmitting the rotation of the rotor, and via the reduction mechanism And a conversion mechanism that converts the transmitted rotation into a driving force in a direction along the optical axis to move the moving lens body linearly.

  In the present invention, since a speed reduction mechanism is provided between the electromagnetic mechanism and the conversion mechanism, a large torque can be obtained. In addition, since the lens is driven via the deceleration mechanism, the position of the lens can be controlled with high accuracy.

  In the present invention, the conversion mechanism is engaged with a cylindrical cam cylinder rotatable around the optical axis and a cam groove formed on the movable lens body side and extending in the circumferential direction of the cam cylinder. It is preferable that the speed reduction mechanism is configured to mechanically connect the rotor and the cam cylinder.

  In the present invention, examples of the speed reduction mechanism include an external spur gear that is annularly formed around the optical axis with respect to the cam cylinder side, and an annular internal gear that is disposed so as to surround the external spur gear. Use a differential spur gear reduction mechanism including a gear and a rotor-side rotating member that rotates integrally with the rotor and displaces the meshing position of the external spur gear and the internal spur gear in the circumferential direction. Is preferred.

  In the present invention, as the speed reduction mechanism, an annular tooth portion configured around the optical axis with respect to the rotor side, and each shaft core are connected to the cam cylinder side, and planetary motion is performed on the annular tooth portion. You may use the bevel gear planetary reduction mechanism provided with the some bevel gear.

  In the present invention, as the speed reduction mechanism, an inner tooth portion formed around the optical axis with respect to the rotor side, an outer tooth portion formed around the optical axis inside the inner tooth portion, and A spur gear planetary reduction mechanism having a plurality of spur gears in which each shaft core is connected to the cam cylinder side and planetarily moves between the inner tooth portion and the outer tooth portion may be used.

  In the present invention, the speed reduction mechanism is arranged annularly around the optical axis and rolls by a rotational driving force from the rotor, and holds the plurality of balls so that the balls can roll, and the cam cylinder side A ball retainer-type speed reduction mechanism including a retainer coupled to the head may be used.

  In any of these reduction mechanisms, each member can be arranged in an annular shape, so that an optical path can be secured when mounted on the objective lens driving device.

  In the present invention, a plurality of the lenses and the moving lens bodies are arranged along an optical axis direction, and the plurality of lenses are provided in the cam cylinder via the cam follower portions formed in each of the plurality of moving lens bodies. When applied to a lens driving device having a plurality of cam grooves for driving the lens, the effect is great. That is, in the present invention, since the speed reduction mechanism is provided, sufficient torque can be obtained even when a plurality of lenses are driven by a common drive source.

  Since the lens driving device according to the present invention includes a speed reduction mechanism between the electromagnetic mechanism and the conversion mechanism, a large torque can be obtained. In addition, since the lens is driven via the deceleration mechanism, the position of the lens can be controlled with high accuracy.

  A lens driving device to which the present invention is applied will be described below with reference to the drawings.

[Embodiment 1]
(overall structure)
FIG. 1 is a cross-sectional view of a lens driving device to which the present invention is applied. In FIG. 1 and FIGS. 6 (A), 7 (A), and 8 (A) used for the description of Embodiments 2, 3, and 4 to be described later, the lens is in the wide-angle position in the left half. The right half shows the telephoto position.

  In FIG. 1, the lens driving device 1 of the present embodiment includes a fixed lens 11, a front moving lens 21, and a rear moving lens 31 in order from the subject side along the optical axis direction as a lens system. A diaphragm 23 is fixed to the rear side (back side in the optical axis direction) of the moving lens 21. Of the three lenses, the fixed lens 11 is held by the cylindrical rotation preventing member 12 as a single lens. On the other hand, the moving lens 21 is configured as a moving lens body 20 in which the outer lens holder 22 is integrated, and the moving lens 31 is configured as a moving lens body 30 in which the outer lens holder 32 is integrated. The lenses 21 and 31 and the lens holders 22 and 32 are made of resin such as POM, PA, AS, ABS, and PE.

  As a driving means for driving such two lenses along the optical axis L, in this embodiment, the electromagnetic mechanism 3 is configured around the movable lens bodies 20 and 30, and the electromagnetic mechanism 3 and the movable lens body are provided. As will be described later, a speed reduction mechanism 5 that reduces and transmits the rotation of the rotor of the electromagnetic mechanism 3, and a direction along the optical axis L that transmits the rotation transmitted through the speed reduction mechanism 5. And a conversion mechanism 7 for converting the moving lens bodies 20 and 30 into linear motions.

  In the lens driving device 1 of this embodiment, the optical system, the electromagnetic mechanism 3, the speed reduction mechanism 5, the conversion mechanism 7, and the like are housed in a case 9. The case 9 includes a case main body 91 and a case lid 92 that fits in the case main body 91 from a direction along the optical axis F. The case lid 92 has an opening for securing an optical path.

(Configuration of electromagnetic mechanism 3)
In the lens driving device 1 of the present embodiment, the electromagnetic mechanism 3 has the same structure as the PM stepping motor, and includes a rotor 60 including a ring-shaped magnet 61 whose outer peripheral surface is magnetized in the circumferential direction, and a ring. And a stator 62 facing the outer peripheral surface of the magnet 61. The magnet 61 is disposed so as to surround the movable lens bodies 20 and 30 on the outer peripheral side, and is multipolarized in the circumferential direction. The stator 62 has two drive coils arranged along the optical axis direction. Each of the drive coils is sandwiched between the outer stator core and the inner stator core from both sides in the optical axis direction, and the outer stator core and the first inner stator core have a plurality of pole teeth arranged alternately along the inner peripheral surface of the drive coil. Is formed.

(Configuration of conversion mechanism 7)
FIG. 2 is a perspective view of a rotation preventing member used in the lens driving device shown in FIG. 3A and 3B are an explanatory diagram of a configuration for preventing the moving lens body from rotating in the lens driving device shown in FIG. 1, and an explanatory diagram of a cam groove formed in the cam cylinder. is there.

  In FIG. 1, the conversion mechanism 7 first includes a cylindrical rotation blocking member 12 that prevents the movable lens bodies 20 and 30 from rotating around the optical axis, and a cylindrical cam cylinder 40.

  As shown in FIG. 2, the rotation preventing member 12 is formed with three slits 15 extending in the optical axis direction in parallel in the circumferential direction.

  As shown in FIG. 3A, in the moving lens bodies 20 and 30, projections 221 and 321 as cam follower portions are formed around the lens holders 22 and 32. The projecting portions 221 and 321 are formed at three positions at intervals of 120 °, and the base portions thereof are connecting arm portions 223 that connect the supporting portions 222 and 322 that support the lenses 21 and 31 and the projecting portions 221 and 321. 323. Accordingly, the connecting arm portions 223 and 323 are positioned in the slit 15 of the rotation preventing member 12 in a state where the protruding portions 221 and 321 are projected outward from the rotation preventing member 12 slit 15. Therefore, the rotation of the lens moving bodies 20 and 30 is blocked by the slit 15 of the rotation blocking member 12.

  In this embodiment, one of the three connecting arm portions 223 and 323 is long and curved, so that an elastic force is applied. Therefore, the three protrusions 221 and 321 of the moving lens bodies 20 and 30 can be easily inserted into the cam grooves 41 and 42 of the cam cylinder 40 described below with reference to FIG. The lens body 20 can move in the direction of the optical axis while being supported by the cam grooves 41 and 42 without play.

  In FIG. 1 again, in this embodiment, the cam cylinder 40 is disposed so as to surround the rotation prevention member 12 on the outer peripheral side. Cam grooves 41 and 42 are opened on the inner wall of the cam cylinder 40 as shown in a developed view of FIG. Of the two cam grooves 41, 42, the cam groove 41 corresponds to the protrusion 221 of the front moving lens body 20, and has three oblique linear grooves. Therefore, when the protrusion 221 is engaged with the cam groove 41 and the cam cylinder 40 is rotated, the protrusion 221 moves along the cam groove 41 and the movable lens body 20 moves in the optical axis L direction. Become. The cam groove 42 corresponds to the protrusion 321 of the rear moving lens body 30 and is formed as three arc-shaped grooves. Therefore, when the protrusion 321 is engaged with the cam groove 42 and the cam cylinder 40 is rotated, the protrusion 321 moves along the cam groove 41 and the movable lens body 30 moves in the optical axis L direction. Become.

  The cam cylinder 40 is made of a slippery material, for example, a resin such as POM, PA, AS, ABS, or PE, and is subjected to high-precision groove processing by an inner surface transfer method or the like.

(Configuration of deceleration mechanism 5)
4A and 4B are a cross-sectional view and a bottom view taken along line A1-A1 'of the lens driving device 1 according to Embodiment 1 of the present invention.

  In the lens driving device 1 configured as described above, in this embodiment, as shown in FIGS. 1 and 4A and 4B, between the electromagnetic mechanism 3 and the conversion mechanism 7, that is, the rotor 60 and the cam cylinder. The speed reduction mechanism 5 is configured so as to be mechanically connected to 40.

  In this embodiment, a differential spur gear speed reduction mechanism 5A is used as the speed reduction mechanism 5. This differential spur gear speed reduction mechanism 5A is an outer ring formed around the optical axis L with respect to the cam cylinder 40 side. The spur gear 511, the annular internal spur gear 513 arranged so as to surround the external spur gear 511, and the meshing of the external spur gear 511 and the internal spur gear 513 rotating together with the rotor 60. And a rotor-side rotating member 515 whose position is displaced in the circumferential direction.

  Here, the internal spur gear 513 has a protrusion 514 protruding downward from the rectangular hole 911 of the case 91 so that it can swing in the radial direction, but cannot rotate around the optical axis L. is there. The rotor-side rotating member 515 is a protrusion that protrudes downward from the rotor 60 and contacts the outer peripheral edge of the internal spur gear 513. Further, the rotor 60 is provided with a ring portion 516 inscribed in the external spur gear 511. Further, the number of teeth of the internal spur gear 513 is different from the number of teeth of the external spur gear 511.

  Therefore, in the differential spur gear reduction mechanism 5A, when the rotor 60 rotates, the rotor-side rotating member 515 rotates. As a result, the internal spur gear 5 does not rotate but swings in the radial direction, and the external spur gear The meshing position between 511 and the internal spur gear 513 is displaced in the circumferential direction.

Therefore, if the number of teeth of the internal spur gear 513 is Z1 and the number of teeth of the external spur gear 511 is Z2, the rotation of the rotor 60 is expressed by the following equation (Z1-Z2) / Z1.
It is transmitted with the reduction ratio.

(System configuration example of a camera equipped with the lens driving device 1)
FIG. 5 is a system configuration diagram of a camera equipped with a lens driving device to which the present invention is applied.

  When the lens driving device 1 according to this embodiment is mounted on a camera, an imaging element (not shown) captures reflected light from a subject into the lens 11 and the moving lenses 21 and 31 on the far side along the optical axis. Are arranged).

  In such a camera, as shown in FIG. 5, a zoom driver 81 that realizes a zooming operation by driving the moving lens bodies 20 and 30 having the lenses 21 and 31 and an image signal obtained from the image sensor 82 are processed. An ISP (Image Signal Processor) 83, a storage device 84 for storing image data, a control logic unit 85, one or a plurality of memories 86 for temporarily storing an image for electronic processing, and an optical image or electronic processing It has a display means 87 for displaying an electronic image and an MPU (Micro Processing Unit) 88 as a system controller for controlling these members.

  Here, the camera module corresponding to the lens driving device 1 includes a mechanical part of the lens driving device 1 including the moving lens bodies 20 and 30 including the lenses 21 and 31, a zoom driver 81 of the image sensor 82, and an ISP 83. The control logic unit 85 and the MPU 88 constitute a control unit. In addition, the image sensor 81, the ISP 83, and the control unit constitute an image acquisition unit. The MPU 88 includes a zoom command reading unit that reads a zoom command, serves as an operation position confirmation unit that confirms the operation position of the lenses 211 and 31, and also serves as a current position detection unit that detects the positions of the lenses 21 and 31.

  In addition, by providing a sensor for detecting the positions of the lenses 21 and 31, that is, the positions of the movable lens bodies 20 and 30, the sensor may constitute a part of the current position detecting means. The control logic unit 85 may be incorporated in the MPU 88. The display means 87 includes a display element made up of a liquid crystal element and a display driver that drives the display element. The display driver may be arranged in the circuit board 89. Moreover, as a display element, you may use LED (Light Emitting Diode), EL (Electro Luminescence), and another display element. In addition, when a plurality of memories 86 are provided as shown in FIG. 5, digital zoom can be performed by performing smoother electronic processing (digital processing) using temporarily stored images, or with a plurality of different resolutions. Images can be combined.

(Driving method for moving lenses 21 and 31)
With reference to FIGS. 1-5, the drive method to the optical axis L direction with respect to the moving lens bodies 20 and 30 is demonstrated.

  First, it is assumed that the lenses 21 and 31 are in the wide-angle position that is located on the most front side. The wide-angle position is a position illustrated in the left half of FIG. 1 and is a position where both the moving lens bodies 20 and 30 have moved forward. When the lenses 21 and 31 are in the wide-angle position, the zoom switch is operated, and when the MPU 88 receives an enlargement zooming command, the zoom driver 81 issues a command to drive the moving lens bodies 20 and 30 to the telephoto side. Then, the zoom driver 81 energizes the drive coils 60 and 62 and the rotor 60 rotates. In this embodiment, the rotation of the rotor 60 is transferred to the cam cylinder 40 via the rotor-side rotating member 515, the internal spur gear 513, and the external spur gear 511 that constitute the differential spur gear reduction mechanism 5A as the speed reduction mechanism 5. Communicated. Here, when the cam cylinder 40 rotates in the arrow X direction in FIG. 3B, the lenses 21 and 31 move from the wide-angle position to the telephoto position, and when the cam cylinder 40 rotates in the arrow Y direction in FIG. 31 move from the telephoto position to the wide-angle position.

  That is, when the cam cylinder 40 rotates around the optical axis L in the direction of the arrow X, the protrusions 221 and 321 rotate together with the cam cylinder 40 in the direction of the arrow V in FIG. The parts 223 and 323 abut against the side wall 151 on one side of the slit 15. Accordingly, rotation of the movable lens bodies 20 and 30 around the optical axis is prevented. For this reason, as a result of the protrusions 221 and 321 of the moving lens bodies 20 and 30 moving along the cam grooves 41 and 42 of the cam cylinder 40, the moving lens bodies 20 and 30 move to the back side along the optical axis. . In this way, the moving lens bodies 20 and 30 move from the wide-angle position to the telephoto position as shown in the right half of FIG.

  On the other hand, when the cam cylinder 40 rotates around the optical axis L in the direction of arrow Y, the protrusions 221 and 321 rotate together with the cam cylinder 40 in the direction of arrow W in FIG. Thus, the connecting arm portions 223 and 323 abut against the side wall 152 on the other side of the slit 15. Accordingly, rotation of the movable lens bodies 20 and 30 around the optical axis is prevented. For this reason, as a result of the protrusions 221 and 321 of the moving lens bodies 20 and 30 moving along the cam grooves 41 and 42 of the cam cylinder 40, the moving lens bodies 20 and 30 move forward along the optical axis. In this way, the moving lens bodies 20 and 30 return from the telephoto position shown in the right half of FIG. 1 to the wide-angle position shown in the left half of FIG.

(Effect of this embodiment)
As described above, since the lens driving device 1 according to the present embodiment includes the speed reduction mechanism 5 between the electromagnetic mechanism 3 and the conversion mechanism 7, a large torque can be obtained. Therefore, sufficient torque can be obtained even if the two moving lenses 21 and 31 are driven by the common electromagnetic mechanism 3. Further, since the moving lenses 21 and 31 are driven via the speed reduction mechanism 5, the positions of the moving lenses 21 and 31 can be controlled with high accuracy.

[Embodiment 2]
6A and 6B are a cross-sectional view of the lens driving device according to Embodiment 2 of the present invention and a cross-sectional view taken along the line A2-A2 '. Since the basic configuration of the lens driving device of the present embodiment and the lens driving devices of Embodiments 3 and 4 to be described later is the same as that of Embodiment 1, common portions are denoted by the same reference numerals. The detailed description thereof is omitted.

  6A and 6B, also in the lens driving device 1 of the present embodiment, the speed is reduced so as to mechanically connect the electromagnetic mechanism 3 and the conversion mechanism 7, that is, the rotor 60 and the cam cylinder 40. A mechanism 5 is configured.

  In this embodiment, a bevel gear planetary speed reduction mechanism 5B is used as the speed reduction mechanism 5, and this bevel gear planetary speed reduction mechanism 5B is configured with an annular tooth portion 521 configured around the optical axis L with respect to the lower surface of the rotor 60, Each shaft core is connected to the cam cylinder 40 side, and includes a plurality of bevel gears 523 that make a planetary motion on the annular tooth portion 52.

  Accordingly, the rotation of the rotor 60 is decelerated via the rolling of the bevel gear 523 and transmitted to the cam cylinder 40. Therefore, a large torque can be obtained and the positions of the movable lenses 21 and 31 can be controlled with high accuracy.

[Embodiment 3]
7A and 7B are a cross-sectional view of the lens driving device according to Embodiment 3 of the present invention and a cross-sectional view taken along the line A3-A3 ′.

  7A and 7B, also in the lens driving device 1 of the present embodiment, the speed is reduced between the electromagnetic mechanism 3 and the conversion mechanism 7, that is, the rotor 60 and the cam cylinder 40 are mechanically connected. A mechanism 5 is configured.

  In this embodiment, a spur gear planetary speed reduction mechanism 5C is used as the speed reduction mechanism 5, and the spur gear planetary speed reduction mechanism 5C is formed in an annular shape around the optical axis L with respect to the rotor 60 side. The outer teeth 533 formed in an annular shape around the optical axis L on the lower end side of the rotating element member 12 inside the inner teeth 531 and the respective shaft cores are connected to the cam cylinder 40 side, and the inner teeth A plurality of spur gears 535 that perform a planetary movement between 531 and the external tooth portion 533 are provided.

  Accordingly, the rotation of the rotor 60 is decelerated through the rolling of the spur gear 535 and transmitted to the cam cylinder 40. Therefore, a large torque can be obtained and the positions of the movable lenses 21 and 31 can be controlled with high accuracy.

[Embodiment 4]
8A and 8B are a cross-sectional view of a lens driving device according to Embodiment 4 of the present invention and a cross-sectional view taken along the line A4-A4 '.

  8A and 8B, also in the lens driving device 1 of this embodiment, the speed is reduced so as to mechanically connect between the electromagnetic mechanism 3 and the conversion mechanism 7, that is, the rotor 60 and the cam cylinder 40. A mechanism 5 is configured.

  In this embodiment, a ball retainer type reduction mechanism 5D is used as the reduction mechanism 5. This ball retainer type reduction mechanism 5D is arranged around the optical axis L and is rolled by the rotational driving force from the rotor 60. And a retainer 543 that holds the plurality of balls 541 in a rollable manner and is connected to the cam cylinder 40 side.

  Accordingly, the rotation of the rotor 60 is decelerated via the rolling of the ball 541 and transmitted to the cam cylinder 40. Therefore, a large torque can be obtained and the positions of the movable lenses 21 and 31 can be controlled with high accuracy.

  Since the lens driving device according to the present invention includes a speed reduction mechanism between the electromagnetic mechanism and the conversion mechanism, a large torque can be obtained. In addition, since the lens is driven via the deceleration mechanism, the position of the lens can be controlled with high accuracy.

It is sectional drawing of the lens drive device to which this invention is applied. It is a perspective view of the rotation prevention member used for the lens drive device shown in FIG. (A), (B) is explanatory drawing of the structure for preventing the rotation of a moving lens body in the lens drive device shown in FIG. 1, and explanatory drawing of the cam groove formed in the cam cylinder. (A), (B) is sectional drawing in the A1-A1 'line of the lens drive device which concerns on Embodiment 2 of this invention, and its bottom view. It is a system block diagram of the camera carrying the lens drive device to which this invention is applied. (A), (B) is sectional drawing in the A2-A2 'line of the lens drive device which concerns on Embodiment 2 of this invention, and its bottom view. (A), (B) is sectional drawing in the A3-A3 'line of the lens drive device which concerns on Embodiment 3 of this invention, and its bottom view. (A), (B) is sectional drawing in the A4-A4 'line of the lens drive device which concerns on Embodiment 4 of this invention, and its bottom view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lens drive device 3 Electromagnetic mechanism 5, 5A, 5B, 5C, 5D Deceleration mechanism 7 Conversion mechanism 11 Fixed lens 12 Rotation prevention member 20, 30 Moving lens body 21 Front moving lens 31 Rear moving lens 40 Cam cylinder 60 Rotor

Claims (7)

In a lens driving device having a moving lens body provided with a lens, and driving means for moving the moving lens body along the optical axis of the lens,
The drive means is disposed so as to surround the moving lens body on the outer peripheral side, and includes an electromagnetic mechanism including a rotor that rotates around the optical axis, a reduction mechanism that reduces and transmits the rotation of the rotor, and the deceleration mechanism A lens driving device comprising: a conversion mechanism that converts the rotation transmitted through the mechanism into a driving force in a direction along the optical axis to move the moving lens body linearly. 2. The conversion mechanism according to claim 1, wherein the conversion mechanism is associated with a cylindrical cam cylinder rotatable around the optical axis, and a cam groove formed on the moving lens body side and extending in the circumferential direction on the cam cylinder. With a matching cam follower
The lens driving device, wherein the speed reduction mechanism is configured to mechanically connect the rotor and the cam cylinder.   In Claim 2, the speed-reduction mechanism includes an external spur gear that is annularly formed around the optical axis with respect to the cam cylinder side, an annular internal spur gear that is disposed so as to surround the external spur gear, And a differential spur gear reduction mechanism provided with a rotor-side rotating member that rotates integrally with the rotor and displaces the meshing position of the external spur gear and the internal spur gear in the circumferential direction. A lens driving device.   3. The speed reduction mechanism according to claim 2, wherein the speed reduction mechanism is configured such that an annular tooth portion configured around the optical axis with respect to the rotor side and each shaft core are coupled to the cam cylinder side, and planetary motion is performed on the annular tooth portion. A lens driving device comprising a bevel gear planetary reduction mechanism having a plurality of bevel gears.   3. The speed reduction mechanism according to claim 2, wherein the speed reduction mechanism includes an inner tooth portion formed around the optical axis with respect to the rotor side, an outer tooth portion formed around the optical axis inside the inner tooth portion, and A lens drive characterized in that each shaft core is a spur gear planetary reduction mechanism having a plurality of spur gears that are connected to the cam cylinder side and planetarily move between the inner tooth portion and the outer tooth portion. apparatus.   3. The cam cylinder according to claim 2, wherein the speed reduction mechanism is arranged in a ring around the optical axis and rolls by a rotational driving force from the rotor, and holds the plurality of balls in a rollable manner. A lens drive device characterized by being a ball retainer type speed reduction mechanism having a retainer connected to the side. In any one of Claims 1 thru | or 6, the said lens and the said moving lens body are arrange | positioned in multiple along an optical axis direction,
The lens drive device according to claim 1, wherein the cam cylinder includes a plurality of cam grooves that drive the plurality of lenses via the cam follower portion formed in each of the plurality of moving lens bodies.

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