Actuator for optical device and lens barrel equipped with same

Abstract

An optical device actuator comprises a movable frame (33) including a focusing lens (L11), a main shaft guide (40), a piezoelectric element (36a), a weight unit (36b), a fixed frame (30), and a spring (36c). The piezoelectric element (36a) imparts vibration to a first end (40a) side of the main shaft guide (40). The weight unit (36b) has a first weight (36ba), a small-diameter part (36bc), and a second weight (36bb). The first weight (36ba) is fixed to the piezoelectric element (36a) along an axial direction of the main shaft guide (40). The small-diameter part (36bc) is fixed to an end part of the first weight (36ba) on the opposite side thereof from the piezoelectric element (36a) along the axial direction of the main shaft guide (40), and has elasticity. The second weight (36bb) is fixed via the small-diameter part (36bc) to the first weight (36ba) along the axial direction of the main shaft guide (40).

Description

[Technical Field]

[0001] The present disclosure relates to an actuator for an optical device that drives an optical device such as a lens back and forth along an optical axis, and a lens barrel equipped with the same. [Background technology]

[0002] Conventionally, a vibration actuator for vibrating a guide shaft, such as a smooth impact drive mechanism (SIDM), which is capable of high-speed response, has been used to move a lens frame of a lens barrel back and forth in the optical axis direction. For example, Patent Document 1 discloses a drive device that includes a drive shaft, a piezoelectric element to which a first end of the drive shaft is fixed using adhesive or the like, a support member that supports the second end of the drive shaft in a state in which it can move parallel to the axial direction, and an external force absorbing support part (spring or the like) attached to the piezoelectric element to absorb the effect of an external force that would act on the drive part when the drive part including the drive shaft is subjected to an external force in a direction different from the axial direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2014 / 091656 Summary of the Invention

[0004] However, the above-described conventional drive device configuration has the following problems. In other words, in the configuration of the drive device disclosed in the above publication, even if an external force is applied to the drive shaft or the like in a direction other than the axial direction, the effect of the external force can be mitigated by an external force absorbing support part such as a spring.

[0005] However, in the conventional configuration, a so-called floating structure is adopted in which the first end of the drive shaft is supported in a state in which it can move in the axial direction. In other words, in the conventional configuration, the end of the guide shaft that guides the lens in the optical axis direction is supported in an unstable state. For this reason, when the drive device is mounted on, for example, a lens barrel including a focus lens group, it may be difficult to adjust the optical axes of the focus lens group guided by the guide shaft.

[0006] Furthermore, even if a stable ultrasonic vibration amplitude is obtained in the conventional configuration, if the piezoelectric element is vibrated at a frequency near the peak of a graph showing gain against frequency in order to obtain an even higher ultrasonic vibration amplitude within the stable region, the vibration may be amplified, causing the laminated portion to peel off and fail, resulting in a mechanically fatal resonance mode. An object of the present disclosure is to provide an actuator for optical equipment that can effectively prevent damage to a piezoelectric element due to resonance while ensuring high response characteristics, and a lens barrel equipped with the same.

[0007] The actuator for an optical device according to the present disclosure includes a movable frame including a lens, a guide shaft, a vibration imparting unit, a first weight, a first elastic element, a second weight, a first frame, and an elastic member. The guide shaft supports the movable frame movably along the optical axis of the lens. The vibration imparting unit imparts vibration to a first end of the guide shaft. The first weight is fixed to the vibration imparting unit along the axial direction of the guide shaft. The first elastic element is fixed to an end of the first weight opposite the vibration imparting unit along the axial direction of the guide shaft and has elasticity. The second weight is fixed to the first weight along the axial direction of the guide shaft via the first elastic element. The first frame supports the vibration imparting unit, the first weight, the first elastic element, and the second weight, which are arranged on the first end of the guide shaft. The elastic member is provided on the first end of the guide shaft and presses the vibration imparting unit along the axial direction against the first end of the guide shaft via the first weight, the first elastic element, and the second weight. (Effects of the Invention) According to the actuator for optical equipment according to the present disclosure, it is possible to effectively prevent damage to the piezoelectric element due to resonance while ensuring high response characteristics. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view showing a configuration of a lens barrel equipped with an actuator for an optical device according to an embodiment of the present disclosure. [Figure 2] An exploded view of the components that make up the lens barrel in Figure 1. [Figure 3] An exploded view of the components that make up the third and fourth group units included in the lens barrel of Figure 2. [Figure 4] 4 is a side view showing the direction of vibration applied by a piezoelectric element in the third and fourth group units of FIG. 3. [Figure 5] FIG. 4 is a front view of the third and fourth group unit in FIG. 3, viewed from the image sensor side. [Figure 6] Cross-sectional view of line JJ in Figure 5. [Figure 7] FIG. 3 is a view of the fixed frame included in the lens barrel of FIG. 2, seen from the image plane side. [Figure 8] Cross section of line LL in Figure 7. [Figure 9] FIG. 4 is an exploded perspective view showing the configuration of the periphery of a connection portion between a piezoelectric element and a spindle guide. [Figure 10] FIG. 4 is a cross-sectional view schematically showing the configuration around the piezoelectric element and the configuration of the press-fit portion on the second end side of the spindle guide. [Figure 11] FIG. 10 is an enlarged view showing a portion where the spindle guide is press-fitted into the guide holding frame. [Figure 12A] FIG. 11 is a diagram showing an equivalent vibration model of FIG. 10. [Figure 12B] FIG. 12B is a diagram showing an equivalent vibration model serving as a comparative example to FIG. 12A. [Figure 13A] Graph showing the results of comparing the frequency response characteristics of the guide shaft and weight. [Figure 13B] 12C is a graph showing the results of comparing the frequency response characteristics of the simplified vibration imparting mechanisms of FIGS. 12A and 12B. [Figure 14] A graph showing frequency response characteristics for each ratio of W14 to W15. [Figure 15] FIG. 10 is a perspective view illustrating focus control of the third and fourth group units. [Figure 16] FIG. 10 is an exploded perspective view showing the configuration of the periphery of a connection portion between a piezoelectric element and a main shaft guide included in an actuator for an optical apparatus according to another embodiment of the present disclosure. [Figure 17] FIG. 17 is a diagram showing an equivalent vibration model of the actuator for the optical device shown in FIG. [Figure 18] 17 is a graph showing the results of an experiment comparing the configuration of FIG. 16 with the configuration of a comparative example. [Figure 19] This is an enlarged graph of the bandwidth actually used in the graph of Figure 18. [Figure 20] FIG. 10 is an exploded perspective view showing a configuration including a three-stage weight unit included in an actuator for an optical device according to still another embodiment of the present disclosure. [Figure 21] This is an abstract model of the configuration of a conventional example (Patent Application No. 2020-566172) for simulation purposes, as a comparative example of the configuration shown in Figure 20. [Figure 22] 22 is an exploded perspective view showing a simulation model of the weight unit of FIG. 20, showing a configuration in which the weight unit model as a comparative example shown in FIG. 21 is divided into three (three stages). FIG. [Figure 23] FIG. 23 is an enlarged view of the divided first to third weight unit models included in FIG. 22. [Figure 24A] 21 is a graph showing the response of the simulation model of the present embodiment shown in FIG. 20. [Figure 24B] An enlarged view of part A in Figure 24A. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, more detailed description than necessary may be omitted. For example, detailed description of well-known matters or redundant description of substantially identical configurations may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding by those skilled in the art. The applicant provides the accompanying drawings and the following description to enable those skilled in the art to fully understand the present disclosure, and does not intend for them to limit the subject matter described in the claims.

[0010] (Embodiment 1) A lens barrel 10 equipped with an actuator for an optical device according to an embodiment of the present disclosure will be described below with reference to FIGS. 1 to 15. FIG. (1) Lens barrel configuration 1, lens barrel 10 according to this embodiment includes an optical system including multiple lenses, first unit 11, second unit 12, cam frame 13, third and fourth unit 14, fifth unit 16, exterior unit 17, and base ring 18. Lens barrel 10 is attached to a mount portion of a camera body (not shown) at the base ring 18.

[0011] 1 is the optical axis direction of the optical system of lens barrel 10. Hereinafter, the subject side in the optical axis direction means the side opposite to the image plane side where the image sensor (not shown) of the camera body is disposed. Hereinafter, the optical axis direction of the optical system of lens barrel 10 will be referred to as the optical axis AX direction. (1-1) Optical system configuration As shown in FIG. 2, the optical system of lens barrel 10 is made up of first unit 11, second unit 12, cam frame 13, third and fourth unit 14, fifth unit 16, exterior unit 17, base ring 18, etc.

[0012] First group unit 11 is a cylindrical member, and multiple lenses are arranged inside it on the subject side. First group unit 11 moves forward and backward along the optical axis AX while holding multiple lenses on the subject side. This allows the distance between the lenses to be changed, enabling wide-angle and telephoto photography.

[0013] Second unit 12 is a cylindrical member arranged on the inner circumferential surface side of first unit 11. Second unit 12 holds a plurality of lenses. The plurality of lenses included in second unit 12 are arranged closer to the image plane in the direction of optical axis AX than the plurality of lenses included in first unit 11. 2, cam frame 13 is a cylindrical member with cam grooves formed therein. Cam frame 13 is disposed on the outer peripheral surface side of second unit 12 and third / fourth unit 14. Cam pins provided on the outer peripheral surface of third / fourth unit 14 are fitted into the cam grooves of cam frame 13.

[0014] The third / fourth unit 14 is a focus unit including a focus lens L11, and like the first unit 11 and the second unit 12, holds a plurality of lenses. The third / fourth unit 14 is a substantially cylindrical member and holds a plurality of lenses. As shown in FIG. 2, the plurality of lenses included in the third / fourth unit 14 are arranged closer to the image surface in the direction of the optical axis AX than the plurality of lenses included in the second unit 12. The third / fourth unit 14 also holds a focus lens L11, as shown in FIG. 3. Of the plurality of lenses included in the third / fourth unit 14, the focus lens L11 is arranged closer to the image surface in the direction of the optical axis AX. As shown in FIG. 3, the third / fourth unit 14 is further configured to include a main yoke 31 and an opposing yoke 34 arranged on the outer periphery of a substantially cylindrical fixed frame 30, and a drive coil 33c arranged in a movable frame 33. Driven by a drive unit including the drive coil 33c, the third / fourth unit 14 moves the movable frame 33, including the focus lens L11, back and forth in the direction of the optical axis AX while holding the plurality of lenses.

[0015] Cam pins provided to protrude from the outer peripheral surface of third / fourth unit 14 (fixed frame 30) receive a rotational drive force applied from a rotational drive source and move along cam grooves formed in cam frame 13. In this way, the multiple lenses included in first unit 11 through third / fourth unit 14 can be moved back and forth in the direction of optical axis AX to adjust the distance between the multiple lenses, enabling wide-angle photography, telephoto photography, and the like.

[0016] The detailed configuration of the third / fourth group unit 14 will be described later. 2, fifth unit 16 is a substantially cylindrical member that is arranged on the inner peripheral surface side of first unit 11. Fifth unit 16 holds a plurality of lenses. Cam frame 13 is attached to fifth unit 16 in a relatively rotatable state. 2, exterior unit 17 is a cylindrical member that constitutes the exterior portion of lens barrel 10. An annular focus ring, zoom ring, etc. are rotatably attached to the outer circumferential surface of exterior unit 17.

[0017] Base ring 18 is attached to the end of exterior unit 17 on the image plane side, and together with exterior unit 17 constitutes the exterior portion of lens barrel 10. Base ring 18 is then attached to the camera body (not shown). (1-2) Configuration of the 3rd and 4th group unit 14 Lens barrel 10 of this embodiment is a lens unit that moves focus lens L11 held by movable frame 33 back and forth in the direction of optical axis AX. Specifically, third / fourth group unit 14 that constitutes lens barrel 10 includes, as shown in FIG. 3, fixed frame 30, main yoke 31, magnet (drive unit) 32 (see FIG. 6, etc.), movable frame 33, main shaft guide (guide shaft) 40, sub shaft guide 41, opposing yoke 34, guide holding frame (second frame body) 35, and vibration imparting mechanism (vibration imparting unit) 36.

[0018] In the third / fourth group unit 14, the fixed frame (first frame body) 30, the movable frame 33 that holds the focus lens L11, the main shaft guide 40, the guide holding frame (second frame body) 35, and the vibration imparting mechanism 36 constitute an actuator for optical equipment that moves the movable frame 33 back and forth along the optical axis AX. 3 to 8 show the configuration of the third and fourth group unit 14. Fig. 6 is a cross-sectional view taken along line JJ in Fig. 5, and Fig. 8 is a cross-sectional view taken along line LL in Fig. 7.

[0019] The fixed frame 30 is a substantially cylindrical member that forms the outer shell of the third / fourth group unit 14, and includes a main yoke 31, a magnet 32, a movable frame 33, a main shaft guide (guide shaft) 40, and a sub shaft guide 41. A part of the fixed frame 30 is used as a first frame that forms part of an actuator for optical equipment, which will be described later. As shown in FIGS. 3 and 6, the main yoke 31 is a substantially U-shaped member when viewed from the side, and two main yokes 31 are provided on the outer peripheral surface side of the fixed frame 30 as shown in FIG.

[0020] As shown in Fig. 6, the magnet 32 ​​is provided between the substantially U-shaped portions of the main yoke 31, and constitutes an actuator that drives the movable frame 33 together with a drive coil 33c (described later). The magnet 32 ​​generates a magnetic field M in the Z direction (inward in the radial direction) indicated by the arrow in Fig. 6. More specifically, the magnet 32 ​​arranged on the upper side in Fig. 6 generates a magnetic field M in the downward direction in the figure, and the magnet 32 ​​arranged on the lower side generates a magnetic field M in the upward direction in the figure.

[0021] As shown in Figures 4 and 6, the movable frame 33 is movable back and forth in the direction of the optical axis AX relative to the fixed frame 30, and has a main shaft bearing portion 33a, a sub shaft bearing portion 33b, a drive coil 33c, and a main body portion 33d. The main shaft bearing portion 33a is a through hole formed in the main body portion 33d along the direction of the optical axis AX, and the main shaft guide 40 is inserted into the through hole.

[0022] Similar to the main shaft bearing portion 33a, the sub-shaft bearing portion 33b is a through hole formed in the main body portion 33d along the optical axis AX direction, and the sub-shaft guide 41 is inserted into the through hole. The spindle guide 40 slidably engages with the spindle bearing portion 33a and, as shown in FIGS. 3 and 4, is disposed along the optical axis AX as a guide member for moving the movable frame 33 relative to the fixed frame 30. A first end 40a of the spindle guide 40 in the direction of the optical axis AX is connected to a vibration imparting mechanism 36 (piezoelectric element 36a) described later (see FIGS. 8 and 9). Meanwhile, a second end 40b opposite the first end 40a is supported in a fixed state in a press-fit hole 35a (see FIGS. 10 and 11) formed in the guide holding frame 35. As shown in FIG. 4, when the movable frame 33 is moved, a predetermined vibration is imparted to the spindle guide 40 by the vibration imparting mechanism 36 described later in the vibration imparting direction shown in the figure.

[0023] 10, the first end 40a of the spindle guide 40 is inserted into an insertion hole 30a formed in the fixed frame 30. An annular gap d is formed between the inner peripheral surface of the insertion hole 30a and the outer peripheral surface of the spindle guide 40. The annular gap d is formed so as to surround the outer peripheral surface of the spindle guide 40. The counter shaft guide 41 is inserted into the counter shaft bearing portion 33b and is disposed substantially parallel to the main shaft guide 40, as shown in Figures 3 and 4. One end of the counter shaft guide 41 in the direction of the optical axis AX is held by the fixed frame 30, and the opposite end is held by a guide holding frame 35, which will be described later. The counter shaft guide 41 functions as a guide member for the movable frame 33 so as to maintain the attitude of the movable frame 33 together with the main shaft guide 40 when the movable frame 33 moves back and forth in the direction of the optical axis AX along the main shaft guide 40.

[0024] 6, the drive coil 33c is fixed to the main body 33d side of the movable frame 33, and is disposed near the main yoke 31 and magnet 32 ​​fixed to the fixed frame 30. When the movable frame 33 is moved, a current flows through the drive coil 33c in the X-axis direction perpendicular to the plane of the drawing, as shown in FIG. 6, a magnetic field directed radially inward, generated by the magnet 32, and a current flowing through the drive coil 33c, can generate a Lorentz force F1 in the Y-axis direction (leftward) in the drawing on the movable frame 33. Therefore, when a current flows through the drive coil 33c, the movable frame 33 moves back and forth in the direction of the optical axis AX.

[0025] In the lens barrel 10 of this embodiment, the thrust applied to the movable frame 33 depends on the Lorentz force F1 generated by the magnet 32 ​​and the drive coil 33c. In other words, in this embodiment, the thrust of the movable frame 33 does not depend on the vibration applied from the vibration applying mechanism 36, which will be described later. 5, the main body 33d holds the focus lens L11 in its central portion. A main shaft guide 40 and a sub shaft guide 41 are inserted into a main shaft bearing 33a and a sub shaft bearing 33b, which are provided on the outer periphery of the portion of the main body 33d that holds the focus lens L11.

[0026] The opposing yoke 34 is attached so as to cover the opening of the main yoke 31, which is substantially U-shaped. 3, the guide holding frame 35 is disposed on the image plane side opposite the subject side in the direction of the optical axis AX of the movable frame 33. The guide holding frame 35 holds the ends of the main shaft guide 40 (the second end 40b side) and the sub shaft guide 41 at a position on the image plane side of the movable frame 33.

[0027] The guide holding frame 35 also has a press-fit hole 35a into which the second end 40b of the spindle guide 40 is press-fitted and fixed, and a groove portion 35b formed concentrically with the press-fit hole 35a on the outer periphery of the press-fit hole 35a (see Figures 10 and 11). Here, focus control of the third / fourth group unit 14 will be described. 15, the position detection unit 52 is composed of a sensor magnet 53 fixed to the movable frame 30, and an MR element (not shown) fixed to the fixed frame 30 so as to face the sensor magnet 53. The position detection unit 52 may be composed of an encoder, and may be anything that can detect the position of the movable frame 33 relative to the fixed frame 30.

[0028] The position detection unit 52 is electrically connected to the control unit 51, and outputs the amount of movement of the sensor magnet 53 in the optical axis direction to the control unit 51. A coil terminal portion 55 of the drive coil 33c is electrically connected to the control unit 51. The control unit 51 can move the movable frame 33 to a desired position by passing a drive current through the drive coil 33c based on the current position of the movable frame 33 obtained from the position detection unit 52.

[0029] Furthermore, the control unit 51 is also electrically connected to the vibration imparting mechanism 36 and can control the operation of the vibration imparting mechanism 36 . In this embodiment, the control unit 51 is configured to be able to freely change the vibration magnitude and vibration frequency of the vibration imparting mechanism 36 in accordance with the current position and speed of the movable frame 33. For example, it is preferable that the vibration speed of the spindle guide shaft is greater than the movement speed of the movable frame 33.

[0030] As a result, the relative speed between the spindle guide 40 and the movable frame 33 changes between ± and 0. Therefore, it is possible to cancel out the friction component whose direction is reversed depending on the speed. Furthermore, in this embodiment, when the movable frame 33 moves, the control unit 51 controls the vibration imparting mechanism 36 so that the spindle guide 40 vibrates at a speed that is at least twice the moving speed of the movable frame 33, within a range that does not exceed the limit of mechanical strength.

[0031] This is because if the vibration is made at a speed less than twice the normal speed, when the vibration of the spindle guide 40 reverses, the relative speed between the movable frame 33 moved by the drive coil 33c and the spindle guide 40 vibrated by the vibration imparting mechanism 36 becomes close to 0, and the friction component whose direction reverses depending on the speed cannot be sufficiently offset, and the load such as static friction between the spindle guide 40 and the movable frame 33 increases, causing the vibration imparting mechanism 36 to unintentionally affect the movable frame 33. (1-3) Configuration of vibration imparting mechanism 36 3 and 4, the vibration imparting mechanism 36 is a mechanism that imparts vibration to the main shaft guide 40 in a direction substantially parallel to the axial direction of the main shaft guide 40, and is disposed at a position where it abuts against the end (first end 40a) of the main shaft guide 40 on the subject side, as shown in Figures 7 and 8. The vibration imparting mechanism 36 has a piezoelectric element 36a, a weight unit 36b, a spring 36c, a holder (first frame) 36d, and a buffer sheet (buffer material) 36e, as shown in Figure 3.

[0032] In this embodiment, the vibration imparting mechanism 36 is controlled to impart vibrations within a range of, for example, 20 kHz to 60 kHz. The piezoelectric element 36a is an element having piezoelectricity that generates force when a voltage is applied, and generates ultrasonic vibrations by repeatedly expanding and contracting when an AC voltage is applied. The piezoelectric element 36a is used as an ultrasonic vibrator that applies predetermined ultrasonic vibrations to the spindle guide 40 in order to reduce frictional resistance that occurs between the movable frame 33 (main body part 33d) and the spindle guide 40.

[0033] The application of vibration to the spindle guide 40 by the piezoelectric element 36a will be described in detail later. The weight unit 36b is a substantially cylindrical member with a bottom, and is connected to the end of the piezoelectric element 36a on the subject side, as shown in Fig. 9. Furthermore, the end of the piezoelectric element 36a opposite to the side connected to the first end 40a of the main shaft guide 40 is fixed with an adhesive to the bottom surface of the weight unit 36b. As shown in Figs. 9 and 10, the weight unit 36b has a multi-stage structure including two weights (first and second weights 36ba, 36bb), and has a first weight 36ba, a second weight 36bb, a small diameter portion 36bc, and a flange portion 36bd.

[0034] As shown in Fig. 9, the first weight 36ba is disposed on the side where the piezoelectric element 36a is inserted and is fixed to the end of the piezoelectric element 36a. A flange portion 36bd is provided on the outer peripheral surface of the first weight 36ba. The first weight 36ba has a mass ratio of, for example, 2:1 to the second weight 36bb. In other words, the first weight 36ba has a mass that is approximately two-thirds of the entire weight unit 36b.

[0035] The second weight 36bb is connected to the first weight 36ba via the small diameter portion 36bc along the axial direction of the spindle guide 40, and is formed to include the bottom portion of the substantially cylindrical weight unit 36b with a bottom. As described above, the second weight 36bb has a mass ratio of, for example, 1:2 to the first weight 36ba. In other words, the second weight 36bb has a mass that is approximately 1 / 3 of the entire weight unit 36b.

[0036] In this way, by making the masses of the first weight 36ba and the second weight 36bb different rather than equal, the vibration modes of the first weight 36ba and the second weight 36bb can, in principle, be designed independently, even if there are constraints on the spring constant of the elastic element connecting the two. The small diameter portion 36bc is a portion that connects the first weight 36ba and the second weight 36bb, and has an outer diameter that is smaller than the outer diameters of the first weight 36ba and the second weight 36bb. Therefore, the small diameter portion 36bc has a thinner wall thickness than the first and second weights 36ba and 36bb, resulting in lower rigidity and functioning as an elastic element (first elastic element). That is, the small diameter portion 36bc is fixed to the end of the first weight 36ba opposite the piezoelectric element 36a along the axial direction of the spindle guide 40, and has elasticity.

[0037] The flange portion 36bd is formed on the end of the outer circumferential surface of the substantially cylindrical weight unit 36b on the image plane side, opposite the subject side. The flange portion 36bd is formed in a substantially annular shape that protrudes radially outward from the outer circumferential surface of the weight unit 36b, and is pressed along the axial direction of the spindle guide 40 by a spring 36c, which will be described later. As shown in Fig. 9, spring 36c is an elastic member formed as a solenoid spring, and is attached to the outer peripheral surface side of weight unit 36b. As shown in Fig. 10, one end of spring 36c is engaged with flange portion 36bd of weight unit 36b, and the opposite end is held inside holder 36d, and is disposed in holder 36d in a compressed state.

[0038] As a result, the spring 36c presses the piezoelectric element 36a toward the end face of the first end 40a of the spindle guide 40 via the weight unit 36b along the axial direction of the spindle guide 40 (direction of the optical axis AX). In other words, the spring 36c is provided to transmit the behavior of the piezoelectric element 36a to the spindle guide 40 by biasing the piezoelectric element 36a in a direction that vibrates the spindle guide 40.

[0039] Furthermore, when an external force is applied in a direction intersecting the axial direction of the spindle guide 40, the spring 36c supports the spindle guide 40 in a state in which the spindle guide 40 can move in a direction intersecting the axial direction. This makes it possible to prevent damage to the connection between the end face on the first end 40a side of the spindle guide 40 and the end face of the piezoelectric element 36a facing this. Furthermore, the surface of the spring 36c is coated with vibration-proof grease, which improves the vibration-proofing performance of the vibration imparting mechanism 36.

[0040] That is, in the configuration of this embodiment, the first end 40a side of the spindle guide 40 is fixed to the inner surface side of a holder 36d (described later) via a weight unit 36b and a spring 36c. 9 and 10, the holder 36d is a substantially cylindrical member with a bottom, and contains the piezoelectric element 36a, the weight unit 36b, and the spring 36c in its cylindrical internal space. As described above, the bottom surface of the holder 36d supports the subject-side end of the contained spring 36c. Furthermore, as shown in FIG. 10, the holder 36d is fixed to the fixed frame 30 so as to cover the insertion hole 30a formed in the fixed frame 30.

[0041] As a result, the holder 36d and a part of the fixed frame 30 form a first frame body. 9 and 10, the buffer sheet 36e is a sheet-like member made of polyimide resin or the like, and is held between the end face of the first end 40a side (object side) of the main shaft guide 40 and the end face of the piezoelectric element 36a on the image plane side by the biasing force of the spring 36c. The end face of the main shaft guide 40 on the first end 40a side and the opposing end face of the piezoelectric element 36a are connected via the buffer sheet 36e.

[0042] <Applying vibration to the spindle guide 40> In this embodiment, the piezoelectric element 36a applies a predetermined ultrasonic vibration to the spindle guide 40 along the vibration application direction (a direction substantially parallel to the axial direction) shown in FIG. 4 so that the static friction generated between the movable frame 33 (main body portion 33d) and the spindle guide 40 changes to dynamic friction. The piezoelectric element 36a is made of piezoelectric ceramics such as lead zirconate titanate (Pb(ZrTi)O3), barium titanate (BaTiO3), lead titanate (PbTiO3), or the like.

[0043] Ultrasonic vibrations are elastic vibration waves (sound waves) with high frequencies that are inaudible to the human ear (for example, sounds with frequencies of 20 kHz or more that cannot be sensed by the ear as steady sounds), and in a broad sense refer to sounds that are used for purposes other than human hearing, regardless of whether they are audible to humans. Here, if the acceleration at which the spindle guide 40 vibrates due to the ultrasonic vibration is α and the mass of the movable frame 33 is mk, the force required for the movable frame 33 to vibrate at the same acceleration α as the spindle guide 40 is α × mk. Furthermore, the force that can be transmitted from the spindle guide 40 to the movable frame 33 is the friction force T acting between the spindle guide 40 and the movable frame 33.

[0044] In the state of T≧α×mk, the spindle guide 40 and the movable frame 33 move substantially integrally. That is, the movable frame 33 vibrates at an acceleration α in accordance with the vibration of the spindle guide 40 at the acceleration α caused by the piezoelectric element 36a. At this time, the force (friction force T) that can be transmitted to the movable frame 33 is equal to or greater than the force (α×mk) required to vibrate the movable frame 33 at the acceleration α. ​​Therefore, the vibration of the spindle guide 40 is transmitted to the movable frame 33 at the same acceleration α, and the spindle guide 40 and movable frame 33 move approximately as one unit without slipping relative to each other.

[0045] On the other hand, in the state of T<α×mk (relationship (1)), the spindle guide 40 and the movable frame 33 do not move together, and a relative slip occurs. In other words, even if the piezoelectric element 36a causes the spindle guide 40 to vibrate at an acceleration α, the movable frame 33 cannot vibrate at the acceleration α, and instead does not vibrate, or vibrates at an acceleration smaller than the acceleration α. ​​When vibrating at an acceleration smaller than the acceleration α, the amplitude of the movable frame 33 is smaller than the amplitude of the spindle guide 40. At this time, the force (friction force T) that can be transmitted to the movable frame 33 is smaller than the force (α × mk) required for the movable frame 33 to vibrate at the acceleration α. ​​For this reason, the vibration of the spindle guide 40 cannot be transmitted to the movable frame 33 at the same acceleration α, and relative slippage occurs between the spindle guide 40 and the movable frame 33.

[0046] Furthermore, in the state where T<α×mk, as long as the vibration caused by the piezoelectric element 36a continues, relative slippage continues to occur between the spindle guide 40 and the movable frame 33. In this state, the friction between the spindle guide 40 and the movable frame 33 becomes kinetic friction rather than static friction. In other words, while vibration by the piezoelectric element 36a continues in the state where T<α×mk, a state of dynamic friction is always maintained between the spindle guide 40 and the movable frame 33. Generally, dynamic friction force is smaller than static friction force. Therefore, when the state in which dynamic friction is generated is maintained, the movable frame 33 can be driven with a driving force that is smaller than that in the state in which static friction is generated.

[0047] Furthermore, if a dynamic friction state is maintained, the so-called stick-slip phenomenon, which occurs when an object transitions from a static friction state to a dynamic friction state when it starts to move, does not occur. As a result, by maintaining a dynamic friction state, an object can be moved with a small driving force without stick-slip occurring, which is advantageous for high-precision driving of minute movement amounts.

[0048] Furthermore, in the state where T<α×mk, the movable frame 33 vibrates at an acceleration smaller than the acceleration α. ​​In other words, the movable frame 33 may vibrate at an amplitude smaller than that of the main shaft guide 40. This vibration amount is smaller than the amplitude of the main shaft guide 40 and smaller than the amplitude of the piezoelectric element 36a. The amplitude of the piezoelectric element 36a is sufficiently smaller than the accuracy required for position control of the driven body (movable frame 33), for example, 1 / 10 or less. Therefore, even if the driven body (movable frame 33) vibrates due to the piezoelectric element 36a, this does not pose a problem in terms of position control.

[0049] As a result, the ultrasonic vibrations applied from the piezoelectric element 36a to the spindle guide 40 can effectively reduce the frictional resistance at the contact portion between the main body 33d of the movable frame 33 and the spindle guide 40. As a result, the Lorentz force F1 (see FIG. 6) generated by the actuator (the magnet 32 ​​and the drive coil 33c) can move the movable frame 33 to a desired position at high speed and with high precision.

[0050] Fig. 12A is an equivalent vibration model showing the configuration of a vibration imparting mechanism 101, which is a simplification of the vibration imparting mechanism 36 of the present disclosure. Fig. 12B is an equivalent vibration model showing the configuration of a vibration imparting mechanism 201 as a comparative example of the vibration imparting mechanism 36 of the present disclosure. That is, in the configuration of vibration imparting mechanism 101 of the present disclosure shown in Fig. 12A, weight unit 36b is configured as a two-stage multi-stage (first and second weights 36ba, 36bb) connected to each other via an elastic element (small diameter portion 36bc). In contrast, in the configuration of vibration imparting mechanism 201 of the comparative example shown in Fig. 12B, it is configured as a single rigid body.

[0051] Note that 102 and 202 indicate configurations corresponding to an abstract mass element obtained by adding up the masses of the piezoelectric element 36a and the weight unit 36b, and 303 and 403 indicate configurations corresponding to a spring element made of the material of the piezoelectric element 36a. 103 and 203 indicate configurations corresponding to the spring 36c, 104 and 204 indicate configurations corresponding to the spindle guide 40, and 105 and 205 indicate configurations corresponding to the groove 35b. 106 and 206 indicate configurations corresponding to an abstract thrust generating portion of the piezoelectric element 36a, 107 indicates configurations corresponding to the small diameter portion (first elastic element) 36bc of the present disclosure, and 304 indicates configurations corresponding to the second weight connected to 102 by 107.

[0052] Furthermore, x and X indicate positions on the axial directions 109 and 209 of the weight unit 36b and the spindle guide 40, and F and (-F) are the excitation forces (expansion and contraction forces) generated by the piezoelectric element 36a at the position 106. Note that in the simplified vibration imparting mechanisms 101 and 201, the buffer sheet 36e is omitted. First, the following equation (100) shows the transfer function from the excitation force (-F) to the weight position x of the vibration imparting mechanism 201 as a simplified comparative example shown in FIG. 12B, and the following equation (101) shows the transfer function from the excitation force F to the spindle guide position X.

[0053]

number

[0054]

number

[0055] The characteristics of equations (100) and (101) are expressed as quadratic forms with anti-resonance points at W1 and W2 and resonance points at W3 and W4 (see FIG. 13A). In this configuration, the following relational expressions are satisfied: W4 <W1<W3 W2×10 <W4 20×1000 <W4 / 2π 50×1000 <W3 / 2π (In the above equations, W1, W2, W3, and W4 are in radians per second.) At this time, the vibration characteristics on the spindle guide 40 side are expressed by equation (101) in the configuration of the comparative example, and are expressed by equation (102) in the configuration of this embodiment.

[0056]

number

[0057] That is, as shown in FIG. 13B, according to the configuration of this embodiment, the peak portion of the gain with respect to frequency that appears in the graph of the comparative example indicated by the dashed line is eliminated, and one relatively gentle peak appears. Therefore, in the region where high response performance is obtained, it is possible to effectively suppress the occurrence of defects such as mechanically fatal resonance modes that cause peeling of the laminated portion of the piezoelectric element 36a. As a result, compared to the configuration of the comparative example, the degree of freedom in selecting the vibration frequency in design can be increased.

[0058] Furthermore, among the determined W12, W13, W14, W15, and W16 in the above-described mechanical elements, in the band where the maximum response amount of the characteristics of this embodiment shown in FIG. 13B is obtained, W14 and W15 are elements that in principle have a large effect on the characteristics, and therefore, in terms of design, they must satisfy the following conditions (see FIG. 14). 0.725 <W15 / W14<0.8 ·····(2) When this ratio (W15 / W14) is 0.725 or less, the response gain (vibration amplitude) decreases. On the other hand, when W15 / W14 exceeds 0.8, the response gain (vibration amplitude) has a strong tendency to oscillate, as shown in FIG.

[0059] From the above results, it is preferable that the ratio indicated by W15 / W14 satisfies the above relational expression (2). (Embodiment 2) The configuration of an actuator for an optical device according to an embodiment of the present disclosure will be described below with reference to FIGS.

[0060] As shown in FIG. 16, the actuator for optical equipment of this embodiment is characterized in that, instead of the multi-stage weight unit 36b of the first embodiment, the weight is multi-staged by combining a single weight unit 36b with a washer (second weight) 136. According to the configuration of this embodiment, the weight unit 36b and the washer 136 are connected via an elastic element, thereby forming a multi-stage weight (first and second weights).

[0061] After assembling the piezoelectric element 36a, weight unit 36b, spring 36c, holder 36d, spindle guide 40, etc., the inner diameter portion of the washer 136 is adhesively fixed (elastically supported) to the outer periphery of the tip portion of the weight unit 36b that protrudes from the center hole of the holder 36d. This allows the comparison between the configuration of the comparative example without the washer 136 and the configuration of this embodiment with the washer 136 attached to be compared under substantially the same conditions.

[0062] Fig. 17 is an equivalent vibration model that schematically shows the experimental model. As shown in Fig. 17, the piezoelectric element 36a engages with the outside, and the added washer 136 and elastic adhesive (first elastic element) 137 become branches extending therefrom. Therefore, excluding the elastic adhesive (first elastic element) 137 and washer 136 that form the branches, the structure of this embodiment is exactly the same as the structure of the conventional example shown in Figure 12B, and the basic structure of its characteristics (shape of the frequency characteristics) is also similar.

[0063] Here, this added branch portion (elastic adhesive (first elastic element) 137, washer 136) acts as a kind of vibration damper (generally a structure called a dynamic vibration absorber) that is attached to the structure of the conventional example, mitigating the sharp resonance points seen in the conventional example and narrowing the prohibited area for setting the vibration frequency. Here, the characteristics of the configuration of this embodiment will be described with reference to FIGS.

[0064] FIG. 18 shows the results of an experiment comparing the configuration of this embodiment with a comparative example. In FIG. 18, the characteristics obtained with the configuration of this embodiment are shown by a solid line, and the characteristics obtained with the configuration of the comparative example are shown by a dashed line. FIG. 18 shows that the extremely sharp resonance peaks that were prominent in the comparative example shown by the dashed line are alleviated by adding the configuration of this embodiment (washer 136 and elastic adhesive 137) and change to a gentle slope.

[0065] Here, the first elastic element 137 and the washer 136 effectively alleviate the resonance point of W4 in the frequency band used, but have no effect on the resonance point of W3, which is a local vibration mode around the piezoelectric element in the high frequency band. Next, FIG. 19 shows an enlarged view of the band portion actually in use in the graph of FIG.

[0066] As shown in FIG. 19, in the configuration of the comparative example, in order to place the drive frequency at a point that is far enough away from the resonance point w101 (22 kHz), the drive frequency is set to w102 (33 kHz), with a design preference of approximately 1.5 times (or 0.67 times) being considered. On the other hand, in this embodiment, in principle, the drive frequency can also be set to w103 (27 kHz).

[0067] According to the configuration of this embodiment, the amplitude ratio compared to the comparative example is +4.5 dB (1.7 times), which indicates the possibility of obtaining a large amplitude. As described above, according to the configuration of this embodiment, the stepped structure can be very simply added to the conventional method to achieve an improvement in the amplitude amount to the extent shown here. [Other embodiments] Although one embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment, and various modifications are possible without departing from the gist of the disclosure.

[0068] (A) In the above embodiment, the weight unit 36b has been described as having a two-stage structure including the first weight 36ba and the second weight 36bb, but the present invention is not limited to this. For example, as shown in FIG. 20, the weight unit may have a multi-stage configuration of three or more stages, such as a weight unit 336b having two small diameter portions 36bc between two first weights 36ba and two second weights 36bb, and a third weight 36be between the two small diameter portions 36bc.

[0069] More specifically, a configuration with three or more stages will be described below with reference to FIGS. 21 to 24. FIG. That is, when the number of stages is increased, the above-mentioned response equation becomes higher order (8th order equation, 10th order equation), and the calculation becomes complicated. Here, as a third embodiment, the significance of the case of increasing the number of stages to three will be explained using simulation results.

[0070] Figure 21 shows an abstract model of the configuration of the conventional example (Patent Application No. 2020-566172) for simulation purposes. In FIG. 21 , reference numeral 240 denotes a spindle guide model corresponding to the spindle guide 40. Similarly, reference numeral 236e denotes a buffer sheet model corresponding to the buffer sheet 36e. Reference numeral 236a denotes a piezoelectric element model corresponding to the piezoelectric element 36a. Reference numeral 236b denotes a weight unit model corresponding to the weight unit 36b. Reference numeral 235 denotes a frame model A fixed to an absolute coordinate system in the simulation. Reference numeral 236d denotes a frame model B fixed to an absolute coordinate system in the simulation. Reference numeral 255 denotes an adhesive bonding model, which adhesively bonds the piezoelectric element model 236a and the weight unit model 236b. Reference numeral 235ab denotes a spindle elastic body model, which elastically bonds the spindle guide 240 and the frame model A 235. Reference numeral 236c denotes a spring elastic element model, which elastically bonds the weight unit model 236b and the frame model B 236d.

[0071] FIG. 22 shows a simulation model of this embodiment, which has a configuration in which the weight unit model 236b shown in FIG. 21 is divided into three (three stages). In the configuration shown in Fig. 22, reference numeral 336ba denotes a first weight unit model, reference numeral 336bb denotes a second weight unit model, and reference numeral 336bc denotes a third weight unit model.

[0072] FIG. 23 is an enlarged view of the divided first to third weight unit models 336ba, 336bb, and 336bc included in FIG. The first weight unit model 336ba is adhesively bonded to the piezoelectric element model 236a at a first end thereof by the adhesive bonding model 255, and is elastically coupled to the elastic body model 336ca at a second end opposite to the first end.

[0073] The second weight unit model 336bb is elastically coupled to the first elastic body model 336ca at a first end thereof, and is elastically coupled to the second elastic body model 336cb at a second end opposite to the first end thereof. The third weight unit model 336bc is elastically coupled to the second elastic body model 336cb at a first end thereof, and is elastically coupled to the spring elastic element model 236c at a second end opposite to the first end thereof.

[0074] 24A and 24B show the responsiveness of the simulation model of this embodiment. In FIGS. 24A and 24B, the results of this embodiment are shown by solid lines, and the characteristics of the conventional example are shown by dotted lines. In Fig. 24A, in this embodiment, a local gain change can be seen near the target vibration frequency of 30 kHz (see part A of the dashed line in the figure). Fig. 24B is an enlarged view of the area near 30 kHz in Fig. 24A.

[0075] In FIG. 24B, it can be seen that the local gain change forms a local flat portion 400 (stable region) compared to the characteristic (dotted line) of the conventional example. In this flat region, an improvement in vibration amount of approximately 3 dB to 5 dB (1.4 to 1.8 times) is observed compared to the characteristics of the conventional example (dotted line). The above simulation results show that a configuration with three stages of weight units also provides significant performance benefits.

[0076] In actual design, for example, rubber, elastic resin, or the like may be used as an elastic element connecting the multiple weights arranged in multiple stages. (B) In the above embodiment, an example has been described in which the first weight 36ba has a larger mass than the second weight 36bb (2 / 3 and 1 / 3 of the mass of the weight unit 36b), but the present invention is not limited to this.

[0077] For example, the multi-stage weight units may have the same mass, or may have a multi-stage weight unit configuration with a difference in mass at a ratio other than 2:1. (C) In the above embodiment, an example has been described in which a constricted portion (small diameter portion 36bc) that is thinner and less rigid than the first weight 36ba and the second weight 36bb is used as the elastic element connecting the first weight 36ba and the second weight 36bb. However, the present invention is not limited to this.

[0078] For example, rubber, elastic resin, or the like may be used as an elastic element connecting the multiple weights arranged in multiple stages. (D) In the above embodiment, an example was described in which the buffer sheet 36e was provided between the end face of the spindle guide 40 on the first end 40a side and the end face of the piezoelectric element 36a facing the end face. However, the present disclosure is not limited to this.

[0079] For example, the end face of the spindle guide 40 on the first end 40a side and the end face of the piezoelectric element 36a facing this may be fixed with an adhesive. However, as in the above embodiment, by providing a buffer material such as the buffer sheet 36e between the end face of the spindle guide 40 on the first end 40a side and the end face of the piezoelectric element 36a facing it, it is possible to more effectively prevent damage to the connection portion between the end face of the spindle guide 40 on the first end 40a side and the end face of the piezoelectric element 36a facing it.

[0080] (E) In the above embodiment, an example has been described in which the second end 40b side of the spindle guide 40 is press-fitted and fixed into the press-fit hole 35a of the guide holding frame 35. However, the present disclosure is not limited to this. For example, the second end of the spindle guide is not limited to being fixed by press-fitting, and may be fixed using an adhesive or the like.

[0081] (F) In the above embodiment, an example has been described in which the actuator for an optical device according to the present disclosure is applied to the third / fourth group unit 14 included in the lens barrel 10 having multiple lens groups. However, the present disclosure is not limited to this. The application of the actuator for optical equipment according to the present disclosure is not limited to, for example, the fourth group unit of a lens barrel, but may also be an actuator that drives an image sensor or other movable frames.

[0082] (G) In the above embodiment, an example has been described in which vibration is applied from the vibration applying mechanism 36 to the spindle guide 40 in a direction substantially parallel to the axial direction of the spindle guide 40. However, the present disclosure is not limited to this. The vibration applied to the spindle guide from the vibration applying portion may be applied in a direction intersecting the axial direction, for example, when reducing dynamic friction resistance.

[0083] (H) In the above embodiment, an example has been described in which ultrasonic vibration is applied from the vibration applying mechanism 36 to the spindle guide 40. However, the present disclosure is not limited to this. The vibrations applied from the vibration applying unit are not limited to ultrasonic vibrations, and any vibrations that reduce the frictional resistance occurring between the movable frame and the main shaft guide may be applied, for example, vibrations in the audible range.

[0084] Furthermore, the ultrasonic vibrations applied from the vibration applying unit are not limited to the range of 20 kHz to 60 kHz described in the above embodiment, and ultrasonic vibrations outside this range may also be applied. (I) In the above embodiment, an example has been described in which a solenoid spring is used as the elastic member, but the present disclosure is not limited to this.

[0085] For example, other elastic members such as leaf springs may be used in addition to the solenoid springs. That is, the elastic member is not particularly limited as long as it presses the guide shaft in the axial direction. (J) In the above embodiment, a configuration has been described in which a part of the fixed frame 30 serving as the first frame and the guide holding frame 35 serving as the second frame are provided as separate members. However, the present disclosure is not limited to this.

[0086] For example, the first frame and the second frame may be integrated into one body. (K) In the above embodiment, an example has been described in which anti-vibration grease is applied to the spring 36c, but the present invention is not limited to this. For example, it is not essential to apply vibration-proof grease to elastic members such as springs, and they may not be applied. [Industrial Applicability]

[0087] The actuator for optical equipment of the present disclosure has the effect of being able to effectively prevent damage to the piezoelectric element due to resonance while ensuring high response characteristics, and is therefore widely applicable as an actuator to be mounted in various optical equipment. [Explanation of symbols]

[0088] 10 Lens barrel 11 1st group unit 12 2nd group unit 13 Cam frame 14 3rd and 4th group units 16 5th group unit 17 Exterior unit 18 Base Ring 30 Fixed frame (first frame) 30a Insertion hole 31 Main York 32 Magnet (drive unit) 33 Movable frame 33a Main shaft bearing part 33b Counter shaft bearing part 33c Drive coil (drive unit) 33d Main body 34 Opposing Yoke 35 Guide holding frame (second frame) 35a press-fit hole 35b Groove 36 Vibration mechanism (vibration applying part) 36a Piezoelectric element (vibration applying part) 36b weight unit 36ba 1st weight 36bb 2nd weight 36bc small diameter part (first elastic element) 36bd flange 36c Spring (elastic member) 36d Holder (first frame) 36e Cushioning sheet (cushioning material) 40 Main shaft guide (guide shaft) 40a 1st end 40b 2nd end 41 Sub-shaft guide 51 Control section 52 Position detection unit 53 Sensor Magnet 55 Coil terminal 101 Vibration mechanism 103 Weight Unit 104 Spring 105 Spindle guide 106 Groove 107 Piezoelectric element 109 Axial direction 136 Washer (second weight) 137 Elastic adhesive (first elastic element) 336b Weight Unit 336be 3rd weight AX optical axis d Gap F1 Lorentz force L11 focus lens M magnetic force

Claims

1. a movable frame including a lens; a guide shaft that supports the movable frame so that the movable frame is movable along the optical axis of the lens; a vibration applying unit that applies vibration to a first end side of the guide shaft; a first weight fixed to the vibration applying portion along the axial direction of the guide shaft; a first elastic element having elasticity and fixed to an end of the first weight on the opposite side to the vibration applying portion along the axial direction of the guide shaft; a second weight fixed to the first weight along the axial direction of the guide shaft via the first elastic element; a first frame supporting the vibration applying portion, the first weight, the first elastic element, and the second weight, which are disposed on the first end side of the guide shaft; an elastic member provided on the first end side of the guide shaft and pressing the vibration applying portion in the axial direction against the first end of the guide shaft via the first weight, the first elastic element, and the second weight; An actuator for an optical device comprising:

2. The first weight has a different mass from the second weight. The actuator for an optical device according to claim 1 .

3. a third weight provided between the first elastic element and the second weight in the axial direction of the guide shaft and fixed to an end of the first elastic element opposite to the first weight; a second elastic element that connects the third weight and the second weight in the axial direction of the guide shaft and has elasticity; Furthermore, 3. The actuator for optical equipment according to claim 1 or 2.

4. The apparatus further includes a second frame body that supports a second end side of the guide shaft opposite to the first end side in a fixed state.

3. The actuator for optical equipment according to claim 1 or 2.

5. The vibration applying portion is provided with a shock absorbing material disposed between the first end of the guide shaft and the vibration applying portion.

3. The actuator for optical equipment according to claim 1 or 2.

6. The cushioning material is formed in a sheet shape. The actuator for an optical device according to claim 5 .

7. the second frame has a press-fitting hole into which the second end of the guide shaft is fixedly supported by press-fitting; The actuator for an optical device according to claim 4.

8. The second frame further has a groove formed concentrically with the press-fit hole on the outer circumferential side of the press-fit hole. The actuator for an optical device according to claim 7 .

9. The elastic member is disposed between the second weight and the first frame.

3. The actuator for optical equipment according to claim 1 or 2.

10. The elastic member is a solenoid spring. The actuator for an optical device according to claim 9.

11. The elastic member is coated with vibration-proof grease.

3. The actuator for optical equipment according to claim 1 or 2.

12. a first end of the vibration applying portion opposite to the end connected to the guide shaft is adhesively fixed to the first weight; 3. The actuator for optical equipment according to claim 1 or 2.

13. the vibration applying unit applies vibration to the first end of the guide shaft along the axial direction of the guide shaft.

3. The actuator for optical equipment according to claim 1 or 2.

14. The vibration applying unit is a piezoelectric element.

3. The actuator for optical equipment according to claim 1 or 2.

15. The lens is a focus lens.

3. The actuator for optical equipment according to claim 1 or 2.

16. The actuator for optical equipment according to claim 1 or 2; a plurality of lens groups arranged so that the direction of the optical axis is aligned with that of the lens; A lens barrel comprising:

Images