WO2008023432A1

WO2008023432A1 - Lens drive device

Info

Publication number: WO2008023432A1
Application number: PCT/JP2006/316709
Authority: WO
Inventors: Yoshiya Usami
Original assignee: Pioneer Corporation
Priority date: 2006-08-25
Filing date: 2006-08-25
Publication date: 2008-02-28

Abstract

A lens drive device (150) has (i) support sections (20 and others) and (ii) a movable section (100) movably connected to the support sections through a pair of elastic members (21A) and having an objective lens. One end of each first elastic member is fixed to the movable section, and the other end of each elastic member is fixed to the support section. A second elastic member (21B) is formed projected from a part of each first elastic member. The forward end of each second elastic member is joined to the movable section or the support section.

Description

Specification

Lens drive device

Technical field

The present invention relates to the structure of a lens driving device for a disc player that records information on a disc-shaped recording medium or reads recorded information.

Background art

[0002] When reading information from an optical disc (optical recording medium) on which information is optically recorded, the objective lens is driven in the lens optical axis direction (focus direction) in order to focus the read beam on the disc surface, The objective lens is driven in the direction perpendicular to the lens optical axis direction (tracking direction) to cause the reading beam to follow the information track, or the objective lens is applied to the disk surface in order to irradiate the optical axis of the reading beam perpendicular to the disk surface. There is known a lens driving device that is driven in the warp direction (tilt direction).

[0003] Patent Document 1: Japanese Unexamined Patent Publication No. 2003-123286

Patent Document 2: Japanese Patent Laid-Open No. 2001-229556

Disclosure of the invention

Problems to be solved by the invention

[0004] In Patent Document 1 and the like described above, the control of the vibration attenuation rate in order to attenuate, for example, primary resonance in the focus direction and the tracking direction is an appropriate amount between the linear elastic member and the actuating base. This is done by filling a dumping agent (so-called damping agent). However, if the rotation speed of the optical disk increases, the resonance frequency based on the buckling or twisting of the movable part increases, and it is difficult to sufficiently reduce or eliminate the resonance only by filling the dumping agent. This causes a technical problem. Specifically, when the rotation frequency of the optical disk (for example, 160 kHz) is synchronized with the rolling frequency, “pitching resonance” in the forcing direction or “choing resonance” in the tracking direction may occur. Such a resonance causes a technical problem that the reproduction or recording quality of the optical disk is lowered.

[0005] The present invention has been made in view of the above-described conventional problems. It is an object of the present invention to provide an objective lens driving device capable of appropriately reducing or eliminating the vibration caused by the vibration.

Means for solving the problem

[0006] In order to solve the above problem, the lens driving device according to claim 1 includes: (i) a support portion; and (ii) a movably connected to the support portion via at least a pair of first elastic members. And a movable part having an objective lens, wherein one end of the pair of first elastic members is fixed to the movable part, and the other end of the pair of first elastic members The part is fixed to the support part, and a linear second elastic member protrudes from a part of the first elastic member (a branching base part), and the tip end of the second elastic member is the movable part. Or the support portion.

[0007] The operation and other advantages of the present invention will become apparent from the following embodiments.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a lens driving device according to an embodiment of the present invention as the best mode for carrying out the invention will be described in order.

(Embodiment of Lens Driving Device)

Embodiments according to the lens driving device of the present invention include (0 support part and (i) movably connected to the support part via at least a pair of first elastic members and have an objective lens. A movable part, wherein one end of the pair of first elastic members is fixed to the movable part, and the other end of the pair of first elastic members is attached to the support part. A fixed, part of the first elastic member (branching root part) is formed by projecting a second elastic member that is linear, and the tip of the second elastic member is the movable part or the support part It is joined to.

[0010] According to the embodiment of the lens driving device of the present invention, generally, a magnetic field (magnetic field) is formed between a pair of magnets by arranging a pair of magnets facing each other with a predetermined interval. In this magnetic field, by energizing the coil attached to the side surface of the movable part having the objective lens, the movable part held by the pair of first elastic members fixed to the support part is inclined. Move in the focus direction and tracking direction.

[0011] In particular, in the present embodiment, a part of the first elastic member (as one specific example, a branched root portion The tip end portion of the linear second elastic member formed so as to protrude from () is joined to the movable portion or the support portion. Here, the term “joining” according to the present invention means in addition to the meaning of direct contact or connection, for example, contact or indirect via a member such as a dumping agent (that is, an absorbent that absorbs vibration). It is a broad concept that includes the meaning of connecting.

As a result, based on the second elastic member joined to the movable part or the support part, even if a driving force in the focus direction or the tracking direction is applied to the movable part, for example, pitching resonance (secondary It is possible to prevent almost or completely the occurrence of resonance such as resonance) or singing resonance. In other words, the occurrence of resonance can be effectively reduced or eliminated as compared with an objective lens driving device designed without the second elastic member. As a result of the above, in addition to improving the quality of servo control, it is possible to improve the quality of signal reading and writing on disk-shaped recording media.

In one aspect of the lens driving device of the present invention, the second elastic member protrudes from a substantially central portion (a position where the amplitude of the secondary resonance is maximum) of the first elastic member. Is formed.

[0014] According to this aspect, the second elastic member protrudes from the second elastic member so that the substantially central force of the first elastic member, which is the position where the amplitude of the pitching resonance (secondary resonance) in the focus direction is the maximum, is formed. The distal end portion of the second elastic member is joined to the movable portion or the support portion. Note that “substantially the center” in this case means a midpoint where the distances from both ends are equal in a narrow sense, and in a broad sense, the effect of this embodiment, which has a slight margin, increases. For example, the distance may be a predetermined distance from the midpoint as long as it can be obtained. As a result, the occurrence of this pitching resonance can be prevented more effectively.

[0015] Another aspect of the embodiment of the lens driving device of the present invention includes: (i) a tip portion of the second elastic member, the one end portion, and (ii) a dump between the movable portion. Or (iii) a dumping agent is filled between the tip portion and the other end portion of the second elastic member and (iv) the support portion.

[0016] According to this aspect, a dumping agent (so-called damping agent) is filled between the distal end portion of the second elastic member, the one end portion of the first elastic member, and (ii) the movable portion. Or (m) a dump between the tip of the second elastic member and the other end of the first elastic member and (iv) the support. The agent is filled. Accordingly, since the dumping agent contacts the second elastic member in addition to the first elastic member, the contact area with the dumping agent is increased. Therefore, it is possible to more effectively suppress the low-frequency vibration caused by the dumping agent, for example, based on the primary resonance, and to improve the fixing force of the first elastic member.

[0017] In another aspect of the lens driving device of the present invention, the second elastic member is formed so as to protrude in a substantially horizontal direction from a part (the root of the branch) of the first elastic member. ing.

[0018] According to this aspect, the second elastic member is formed so as to protrude from a part of the first elastic member (as one specific example, the central portion) in, for example, the substantially horizontal direction that is the tracking direction. . Therefore, in the optical axis direction of the objective lens, the second elastic member can be disposed in a space-saving manner in a space having substantially the same thickness as the first elastic member. Therefore, it is possible to reduce the thickness of the lens driving device.

[0019] Power! In addition, the second elastic member is formed so as to protrude from a part of the first elastic member, for example, in a substantially horizontal direction that is the tracking direction. In other words, the plane formed by the first elastic member and the second elastic member is substantially perpendicular to the optical axis direction of the objective lens. Therefore, the first elastic member and the second elastic member can hold the movable portion substantially perpendicular to the optical axis in a state where no other force is applied. As a result, it is possible to save the power required to make the movable part substantially perpendicular to the optical axis, and effectively reduce the power consumption of the control current that flows through the coil in order to perform various servo controls. Is possible.

In another aspect of the embodiment of the lens driving device of the present invention, the second elastic member has a flat plate shape.

[0021] According to this aspect, the shape of the second elastic member is, for example, a flat plate shape having a large width dimension in the tracking direction. Accordingly, since the second elastic member extends in only one direction such as the horizontal direction in the optical axis direction of the objective lens, it can be disposed in the lens driving device with a small space. Therefore, it is possible to reduce the thickness of the lens driving device.

In the aspect related to the second elastic member described above, the flat plate surface of the second elastic member may be configured to be substantially orthogonal to the optical axis direction of the objective lens.

[0023] With this configuration, the shape of the second elastic member is, for example, a width dimension in the tracking direction. The plate-like second elastic member can be disposed substantially perpendicular to the optical axis direction of the objective lens. Here, “substantially vertical” means that the angle formed between each other in a narrow sense is 90 degrees, and in a broad sense, the effect of this embodiment, which has a slight margin, is greatly reduced. As long as it is possible, for example, the angle formed by each other may be 90 ° ± 5 °. Therefore, the first elastic member and the second elastic member can hold the movable portion substantially perpendicular to the optical axis in a state where no other force is applied. As a result, it is possible to save the power required to make the movable part substantially perpendicular to the optical axis, effectively reducing the power consumption of the control current that flows through the coil to perform various servo controls. Is possible.

[0024] In another aspect of the lens driving device of the present invention, the second elastic member has a taper portion from a part of the first elastic member (as a specific example, a central portion). However, it is formed to protrude.

According to this aspect, the second elastic member is formed to protrude from a part of the first elastic member while having the tapered portion. In other words, the width and diameter of the second elastic member are formed in a tapered shape that increases toward the connecting position between the second elastic member and the first elastic member. Therefore, when a twisting or buckling force is applied to the first elastic member and the second elastic member, this force can be distributed to the tapered portion, so the first elastic member and the second elastic member It is possible to effectively prevent a transient force from being applied to the connection position with the member. As a result, it is possible to effectively prevent breakage of the connection position between the first elastic member and the second elastic member.

[0026] In another aspect of the embodiment of the lens driving device of the present invention, the second elastic member and the first elastic member have a Y shape or a U shape. .

[0027] According to this aspect, the second elastic member and the first elastic member have a Y shape or a U shape. Accordingly, since the shapes of the first elastic member and the second elastic member can be made symmetric, the manufacturing process for the first elastic member and the second elastic member can be simplified.

[0028] In another aspect of the embodiment of the lens driving device of the present invention, the first elastic member is formed by protruding a first part of the first elastic member (branch root part) and a third elastic member in a line shape, (i) Second elasticity The tip of the member is joined to the movable part, and the tip of the third elastic member is joined to the support, or (ii) the tip of the second elastic member is the support The tip of the third elastic member is joined to the movable part.

[0029] According to this aspect, the linear third elastic member is formed so as to protrude from a part of the first elastic member, and (i) the distal end portion of the second elastic member is joined to the movable portion, The distal end portion of the elastic member is joined to the support portion. Alternatively, (ii) the distal end portion of the second elastic member is joined to the support portion, and the distal end portion of the third elastic member is joined to the movable portion. Therefore, in addition to the second elastic member described above, based on the third elastic member joined to the support portion or the movable portion, for example, even if a driving force in the focus direction or the tracking direction is applied to the movable portion, It is possible to prevent almost or completely the occurrence of resonance such as pitching resonance (secondary resonance) or bowing resonance.

In another aspect of the embodiment of the lens driving device of the present invention, the pair of first elastic members are arranged on the side of the one end as viewed in a plan view from the optical axis direction of the objective lens, and The one side of the other end side is narrower or wider than the other side.

[0031] According to this aspect, the pair of first elastic members is one of the one end side and the other end side of the first elastic member when viewed in plan from the optical axis direction of the objective lens. Is narrower or wider than the other. In other words, one end of each of the pair of first elastic members is fixed to the movable portion, or the other end is fixed to the support portion so that an imaginary line extending in the longitudinal direction intersects. Accordingly, the rigidity of the movable part with respect to the rotational movement of the disk-shaped recording medium is improved.

As a result, for example, even if a driving force in the focus direction or the tracking direction is applied to the movable part, the occurrence of resonance such as pitching resonance (secondary resonance) or bowing resonance is almost or completely prevented. It is possible.

[0033] These effects and other advantages of the present invention will become more apparent from the embodiments described below.

[0034] As described above, according to the embodiment of the lens driving device of the present invention, (i) the support portion and (ii) the movably connected via the first elastic member and the objective lens A second elastic member protruding from the second elastic member, wherein the second elastic member protrudes from the second elastic member. The tip of the elastic member is joined to the movable part or the support part. As a result, based on the second elastic member joined to the movable part or the support part, for example, even if a driving force in the focus direction or the tracking direction is applied to the movable part, pitching resonance (secondary resonance) or It is possible to prevent almost or completely the occurrence of resonance such as ing resonance. In other words, the occurrence of resonance can be effectively reduced or eliminated as compared with an objective lens driving device designed without the second elastic member. As a result, in addition to improving the quality of servo control, it is possible to improve the quality of signal reading and writing on disk-shaped recording media.

Brief Description of Drawings

FIG. 1 is a plan view showing a basic configuration of a lens driving device 150 according to an embodiment of the present invention (FIG. 1).

(a)) and side view (Fig. 1 (b)).

FIG. 2 is a plan view (FIG. 2 (a)) schematically showing the detailed configuration of the movable portion 100, the support wire 21A, and the support wire groove 22c in the lens driving device 150 according to the present embodiment; FIG. 2 is a plan view (FIG. 2 (b)) schematically showing detailed configurations of a movable portion 100, a support wire 21A, and a support wire groove 22c in a lens driving device 150 according to a comparative example.

FIG. 3 is one and other schematic views (FIGS. 3A and 3B) schematically showing a modification of the branch wire according to the present embodiment.

FIG. 4 is one and other schematic views (FIGS. 4A and 4B) schematically showing a modification of the branch wire according to the present embodiment.

Explanation of symbols

[0036] 10 liter cut base

11, 12 Magnet

20 Support base

21 A support wire

21B branch wire

22a Leader

22b connection

22c Support wire groove 22d wire groove

30 Lens holder

80, 90 coin board

100 moving parts

Example

[0037] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0038] (1) Basic configuration

Next, a basic configuration of the lens driving device 150 according to the embodiment of the present invention will be described with reference to FIG.

[0039] (1 1) Overall configuration

First, the overall configuration of the lens driving device 150 will be described with reference to FIG. FIG. 1 is a plan view (FIG. 1 (a)) and a side view (FIG. 1 (b)) showing a basic configuration of a lens driving device 150 according to an embodiment of the present invention. .

As shown in FIGS. 1 (a) and 1 (b), in the lens driving device 150 according to the embodiment of the present invention, a magnet 11 for forming a magnetic field is formed on a plate-shaped actuator base 10. Alternatively, a pair of L-shaped yokes 13 to which 12 is fixed are arranged to face each other with a predetermined magnetic gap, and are fixed to the actuator base 10 with a plurality of screws 14. Further, a support base 20 is fixed on the actuator base 10 with screws 14, and four support wires 21A of the support base 20 (that is, a specific example of the first elastic member according to the present invention) attach the movable portion 100. At the position between the magnets 11 and 12, it can be tilted and supported so as to be movable up and down and left and right.

[0041] The movable part 100 includes an adhesive or the like on the side surface in the jitter (arrow J) direction of the substantially rectangular lens holder 30 in which the objective lens 31 is housed and the lens holder 30 facing the magnet 11. A fixed coil substrate 80 and a coil substrate 90 fixed with an adhesive or the like on the side surface in the jitter direction of the lens holder 30 facing the magnet 12 are provided. Four holding portions 32a and 32b formed so as to protrude in the tracking direction (arrow T in the figure) of the lens holder 30 are supported by the four support carriers 21A, so that the movable portion 100 can be tilted. At the same time, it is supported so as to be movable in the focus (arrow F in the figure) and tracking directions. [0042] The support wire 21A is composed of a conductive rod-like or plate-like elastic member, one end of which is expanded and formed to form a lead-out portion 22a, and a part of the support wire 21A is formed when the support base 20 is molded. By the outsert molding or the like, it is integrally molded inside the support wire groove 22c provided in the support base 20.

[0043] In particular, in the present embodiment, a linear branch wire 21B (that is, the second elastic wire according to the present invention) formed by protruding a part of the support wire 21A (as one specific example, the central portion) is also provided. The tip of one example of the member is joined to a support base 20 fixed on the actuator base 10. The details of the support wire 21A, the branch wire 21B, and the support wire groove 22c will be described later. Similarly, the other end of the support wire 21A is rolled and formed to form a connection portion 22b, which is fixed to the four holding portions 32a and 32b provided in the lens holder 30 with an adhesive or the like.

A magnetic field (magnetic field) is formed between the magnets 11 and 12 by arranging the magnets 11 and 12 to face each other with a predetermined interval. In this magnetic field, when the coil for tilt control, focus control, and tracking control on the coil substrates 80 and 90 fixed to the lens holder 30 is energized, the movable part 100 tilts, Move in the focus direction and tracking direction.

[0045] (2) Examination of Detailed Configuration, Action, and Effect of Example

Next, with reference to FIG. 2, a detailed configuration according to the present embodiment, and examination of actions and effects will be described. FIG. 2 is a plan view schematically showing the detailed configuration of the movable portion 100, the support wire 21A, and the support wire groove 22c in the lens driving device 150 according to the present embodiment (FIG. 2 (a)). FIG. 2 is a plan view (FIG. 2 (b)) schematically showing the detailed configuration of the movable part 100, the support wire 21A, and the support wire groove 22c in the lens driving device 150 according to the comparative example.

[0046] As shown in FIG. 2 (a), in the lens driving device 150 according to the present embodiment, in particular, it is formed to protrude from a part of the support wire 21A (as one specific example, the central part). The leading end of the linear branch wire 21B (that is, a specific example of the second elastic member according to the present invention) is joined to a support base 20 fixed on the actuator base 10. Here, “joining” according to the present embodiment means indirect through a member such as a dumping agent (that is, an absorbent that absorbs vibration) in addition to the meaning of direct contact, connection, or fixing. Contact, connection, or Is a broad concept with a fixed meaning. Further, the direction in which the branch wire 21B protrudes from a part of the support wire 21A may be substantially parallel to the optical axis of the objective lens 31 or may be substantially orthogonal to the optical axis.

Specifically, the support wire groove 22c is formed in a substantially concave shape in substantially the same direction as the longitudinal direction of the support wire 21A at the four corners of the surface of the support base 20 facing the movable portion 100. The support wire groove 22c is a groove through which the support wire 21A and the branch wire 21B are passed. The support wire groove 22c is filled with a dumping agent (so-called dubbing agent) between the support wire 21A and the branch wire 21B to prevent vibration of the support wire 21A and the branch wire 21B up to a predetermined frequency. Here, the predetermined frequency that can be buffered is, for example, a frequency up to about 60 Hz, which can be adjusted by the type and physical characteristics of the damping agent. This damping agent is a gel-like chemical substance for control, and is filled between the support wire 21A and the branch wire 21B and the support wire groove 22c to buffer the vibration of the support wire 21A and the branch wire 21B. In addition, the fixing force of the support wire 21A and the branch wire 21B is strengthened.

As a result, based on the branch wire 21B joined to the support base 20, even if a driving force in the focus direction or the tracking direction is applied to the movable part, for example, pitching resonance (secondary resonance) or side resonance, etc. It is possible to prevent almost or completely the occurrence of this resonance. As shown in the comparative example of FIG. 2 (b), in the objective lens driving device designed without the branch wire 21B, when the rotation frequency of the optical disk (eg, “160 kHz”) and the rolling frequency are synchronized, It becomes technically difficult to suppress the occurrence of pitching resonance in the focus direction.

On the other hand, in the present embodiment, the distal end portion of the linear branch wire 21B formed so as to protrude from a part of the support wire 21A (as one specific example, the central portion) is Since it is joined to the support base 20 fixed on the inner base 10, the occurrence of resonance can be effectively reduced or eliminated. As a result of the above, in addition to improving the quality of servo control, it is possible to improve the quality of signal reading and writing on disk-shaped recording media.

[0050] In particular, the branch wire 21B is formed from a part of the support wire 21A (as one specific example, the central portion). For example, it is preferably formed so as to protrude in a substantially horizontal direction which is a tracking direction.

. Therefore, in the optical axis direction of the objective lens, the branch wire 21B can be disposed in a space-saving manner in a space having substantially the same thickness as the support wire 21A. Therefore, it is possible to reduce the thickness of the lens driving device.

In other words, the branch wire 21B is formed so as to protrude from a part of the support wire 21A, for example, in a substantially horizontal direction that is a tracking direction. In other words, the plane formed by the support wire 21A and the branch wire 21B is substantially perpendicular to the optical axis direction of the objective lens. Therefore, the support wire 21A and the branch wire 21B can hold the movable part 100 substantially perpendicular to the optical axis in a state where no other force is applied. As a result, it is possible to save power for making the movable part 100 substantially perpendicular to the optical axis, effectively reducing the power consumption of the control current that flows through the coil to perform various servo controls. It is possible to do.

[0052] (3) Modification of branch wire (part 1)

Next, a modification of the branch wire according to the present embodiment will be described with reference to FIG. FIG. 3 is one and other schematic views (FIGS. 3A and 3B) schematically showing a modification of the branch wire according to the present embodiment.

As shown in FIG. 3 (a), in the modification of the branch wire according to the present embodiment, the branch wire 21B protrudes from the substantially central portion of the support wire 21A while having a tapered portion. Formed. In other words, the branch wire 21B is also formed by the branch wire 21B protruding so that the force at the center of the support wire 21A, which is the position where the amplitude of the pitching resonance (secondary resonance) in the focus direction is maximized, and the tip of the branch wire 21B is Bonded to the support base 20. Note that “substantially the center” in this case means a midpoint where the distances from both ends are equal in a narrow sense, and in a broad sense, the effect of this embodiment, which has a slight margin, increases. For example, the medium point force may be separated by a predetermined distance as long as it can be obtained. As a result, it is possible to more effectively prevent the occurrence of the pitching resonance.

[0054] In other words, the width and diameter of the branch wire 21B are formed in a tapered shape that increases toward the connecting position between the branch wire 21B and the support wire 21A. Therefore, when twisting or buckling force is applied to the support wire 21A and branch wire 21B, Since this force can be distributed to the tapered portion, it is possible to effectively prevent a transient force from being applied to the connecting position between the support wire 21A and the branch wire 21B. As a result, it is possible to effectively prevent breakage of the connecting position between the support wire 21A and the branch wire 21B. Note that the support wire 21A and the branch wire 21B may have a Y shape or a U shape. As a result, since the shapes of the support wire 21A and the branch wire 21B can be made symmetric, the manufacturing process of the support wire 21A and the branch wire 21B can be simplified.

[0055] In particular, the shape of the branch wire 21B is preferably, for example, a flat plate shape in which the width dimension in the tracking direction is increased. Therefore, in the optical axis direction of the objective lens, the branch wire 21B extends only in one direction such as the horizontal direction, so that it can be disposed in the lens driving device in a space-saving manner. Therefore, it is possible to reduce the thickness of the lens driving device.

[0056] Power! The shape of the branch wire 21B is, for example, a flat plate with a large width in the tracking direction, and the flat surface of the branch wire 21B is arranged substantially perpendicular to the optical axis direction of the objective lens. Also good. Here, “substantially vertical” means that the angle between each other in a narrow sense is 90 degrees, and in a broad sense, the effect of this embodiment, which has a slight margin, is greatly reduced. As long as it can be obtained, for example, the angle formed by each other may be 90 ° ± 5 °. Therefore, the support wire 21A and the branch wire 21B can hold the movable portion 100 substantially perpendicular to the optical axis in a state where no other force is applied. As a result, it is possible to save power for making the movable part 100 substantially perpendicular to the optical axis, and it is possible to effectively reduce the power consumption of the control current flowing through the coil in order to perform various types of servo control. It is possible to suppress this.

As shown in FIG. 3 (b), in another modification of the branch wire according to the present embodiment, the branch wire 21C is formed so as to protrude from a part of the support wire 21A, and the branch The distal end portion of the wire 21C is joined to the holding portions 32a and 32b via, for example, a wire groove 22d and a dumping agent. Note that the branch wire 21C may be formed inside the pair of support wires 21A as viewed in a plan view from the optical axis direction of the objective lens 31, or may be formed outside the pair of support wires 21A. It may be formed so as to be substantially orthogonal to the axial direction. As a result, branch wire 2 Based on 1C, the occurrence of resonance can be effectively reduced or eliminated.

[0058] (4) Variation of branch wire (part 2)

Next, a modification of the branch wire according to the present embodiment will be described with reference to FIG. FIG. 4 is one and other schematic views (FIGS. 4A and 4B) schematically showing a modification of the branch wire according to the present embodiment.

[0059] As shown in FIG. 4 (a), in the variation of the branch wire according to the present embodiment, as described above, the linear branch formed by protruding the central force of the support wire 21A. The tip of the wire 21B is joined to the support base 20 fixed on the actuator base 10.

[0060] The branch wire 21C is formed so as to protrude from a part of the support wire 21A, and the holding portion 32a, via the tip portion force of the branch wire 21C, for example, the wire groove 22d and the dumping agent, It is joined to 32b. Note that the branch wire 21B and the branch wire 21C may be respectively formed inside the pair of support wires 21A as viewed in a plan view when viewed from the optical axis direction of the objective lens 31, or may be respectively formed outside. They may be formed, or may be formed so as to be substantially orthogonal to the optical axis direction. As a result, it is possible to more effectively reduce or eliminate the occurrence of resonance based on the branch wire 21B and the branch wire 21C.

As shown in FIG. 4 (b), in another modification of the branch wire according to the present embodiment, the tip portion force support wire 21A of the branch wire 21B and other added support wires are used. Together with 21D, it is joined to a support base 20 fixed on the actuator base 10. The other added support wire 21D may be formed on the right side or the left side of the pair of support wires 21A as viewed in a plan view from the optical axis direction of the objective lens 31, and may be formed on the inner side or the outer side. It may be formed in such a manner that it may be arranged so as to be substantially orthogonal or substantially parallel to the optical axis direction.

[0062] In addition to the two support wires 21A described above and one other support wire 21D, a plurality of three-dimensionally or planarly bonded support bases 20 are provided. The support wire may support the movable part 100 with the branch wire. Specifically, as shown in FIG. 1 (b), (i) a new holding part is added between the holding part 32a and the holding part 32b and (ii) ) A new drawer between the drawer 22a and the drawer 22a The support wire 21A and the branching wire 21B that join the new holding part and the new lead-out part may be added. As a result, the occurrence of resonance can be more effectively reduced or eliminated based on the plurality of branch wires 21B and the plurality of support carriers 21D.

In the embodiment described above, the force that the branch wire 21B is formed in a flat plate shape substantially orthogonal to the focus direction is not limited to this. For example, the flat plate surface of the branch wire 21B may substantially intersect the focus surface. Further, the shape of the branch wire 21B is not limited to a flat plate. For example, the branch wire 21B may have a cross-shaped branch wire 21B in which two flat plates are crossed, or a branch wire in which two or more flat plates are crossed. It may be 21B. Further, it may be a branch wire 21B having a substantially circular cross section formed with a diameter larger than that of the shaft portion. In this way, by making the shape in which a plurality of flat plates intersect with each other into a shaft shape having a large diameter, stress against twisting is further increased, and torsional resonance can be prevented.

[0064] Further, the force at which the connecting position between the branch wire 21B and the support wire 21A is formed in a tapered shape is not limited thereto. For example, a shape that is not formed in a tapered shape may be used. In this case, in order to strengthen the connection position of the branch wire 21B and the support wire 21A, a reinforcing member is separately provided in this portion. Can be considered.

The present invention is not limited to the above-described embodiments, and the entire specification can be modified as appropriate without departing from the gist or philosophy of the invention that can be read. The apparatus is also included in the technical scope of the present invention. Industrial applicability

The lens driving device according to the present invention can be used for a lens driving device for reproducing an information recording medium such as an optical disk.

Claims

The scope of the claims

[1] A lens driving device comprising: (a support part; and (i) a movable part that is movably connected to the support part via at least a pair of first elastic members and has an objective lens, One end portions of the pair of first elastic members are fixed to the movable portion, and the other end portions of the pair of first elastic members are fixed to the support portion,

A part of the first elastic member is formed by projecting a second elastic member, and a tip end portion of the second elastic member is joined to the movable portion or the support portion. A lens driving device.

[2] The lens driving device according to [1], wherein the second elastic member is formed so as to protrude from a substantially central portion of the first elastic member.

[3] (i) A dumping agent is filled between the tip end portion and the one end portion of the second elastic member, and (ii) the movable portion, or (iii) the second elasticity 2. The lens driving device according to claim 1, wherein a dumping agent is filled between a tip portion of the member and the other end portion, and (iv) the support portion.

4. The lens driving device according to claim 1, wherein the second elastic member is formed so as to protrude in a substantially horizontal direction from a part of the first elastic member.

[5] The lens driving device according to claim 1, wherein the second elastic member has a flat plate shape.

[6] The flat surface of the second elastic member is substantially orthogonal to the optical axis direction of the objective lens! The lens driving device according to claim 5, wherein:

7. The lens driving device according to claim 1, wherein the second elastic member protrudes while having a partial force taper portion of the first elastic member.

[8] The lens driving device according to claim 1, wherein the second elastic member and the first elastic member have a Y shape or a U shape. .

[9] A partial force linear third elastic member of the first elastic member is formed to protrude,

(i) The distal end portion of the second elastic member is joined to the movable portion, and the distal end portion of the third elastic member is joined to the support portion, or (ii) the second elastic member The tip portion is joined to the support portion, and the tip portion of the third elastic member is joined to the movable portion. The lens driving device according to claim 1, wherein:

The pair of first elastic members is narrower than one of the one end side and the other end side when viewed in plan from the optical axis direction of the objective lens, or 2. The lens driving device according to claim 1, wherein the lens driving device is widened.