JP2007048336A - Optical pickup apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical pickup apparatus in which interval between the optical pickup apparatus and a turntable can be secured when the optical pickup apparatus is moved to innermost peripheral side. <P>SOLUTION: An objective lens drive apparatus 10 of the optical pickup apparatus is provided with a lens holder 2 holding an objective lens 22, a tilting wire 51, a focusing wire 53, and a tracking wire 55 supporting the lens holder 2, and a dumper base 3 supporting these wire. The tilting wire 51 supports a first supporting part 61 of the lens holder 2, the focusing wire 53 and the tracking wire 55 support a second supporting part 62 of the lens holder 2, A focusing coil is wound at the periphery and between the first supporting part 61 and the second supporting part 62. Only the tilting wire 51 exists at the first supporting part 61, and projection quantity of the first supporting part 61 can be suppressed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an optical pickup device used in an optical disc apparatus.

  An optical pickup device used in an optical disk device generally includes an optical base that can move along the radial direction of the optical disk, an objective lens driving device mounted on the optical base, a laser light source that emits laser light, A photodetector for detecting the laser beam reflected by the optical disc, and an optical system for guiding the laser beam emitted from the laser light source to the optical disc and for guiding the laser beam reflected by the optical disc to the photodetector.

  The objective lens driving device includes an objective lens, a lens holder that holds the objective lens, a plurality of actuator coils provided in the lens holder for displacing the lens holder, and a plurality of lenses that support the lens holder at one end. It has a suspension wire and a damper base that supports the other ends of the plurality of suspension wires.

  In an objective lens driving device of an optical pickup device used for an optical disc apparatus compatible with a Blu-ray Disc, tilting control of the objective lens is required in addition to focus control and tracking control of the objective lens. For this reason, a total of six suspension wires (a set of two wires for a focus coil, a wire for a tracking coil, and a wire for a tilting coil) are arranged on both sides of the lens holder that supports the objective lens. It will be.

  As an objective lens driving device for such an optical pickup device, an objective lens driving device 100 as shown in FIG. 5 is known (see Patent Document 1).

  The objective lens driving device 100 includes an objective lens denoted by reference numeral 102, and the objective lens 102 is held by a lens holder 101. A tilting coil 109 for tilting is wound around the outer periphery of the side portion of the lens holder 101.

  Tilting magnets 106 c and 106 d are arranged at positions facing the tilting coil 109. Although not shown in FIG. 5, a focusing coil and a tracking coil are attached to the lens holder 101, and focusing and tracking magnets are disposed at positions facing the focusing coil and the tracking coil.

  Suspension wires 108a and 108b and suspension wires 108c and 108d are arranged in parallel in the horizontal direction on the upper portions 107a and 107b on both sides of the lens holder 101, respectively.

  On the other hand, suspension wires 108e and 108f are disposed on the lower portions 107c and 107d on both sides of the lens holder 101, respectively.

  A total of six suspension wires 108 a to 108 f of the objective lens driving device 100 are connection suspension wires for supplying current to a focusing coil (not shown), a tracking coil (not shown), and a tilting coil 109, respectively. At the same time, the lens holder 101 is supported so as to be displaceable.

  In the objective lens driving apparatus 100, among the four suspension wires locked to the upper portions 107a and 107b on both sides of the lens holder 101, the suspension wires 108a and 108c are the focusing coils, and the suspension wires 108b and 108d are the tracking. It is electrically connected to the coil. The suspension wires 108e and 108f are electrically connected to the tilting coil 109.

  In the configuration as described above, the lens holder 101 (and the objective lens 102) is moved (moving in the focusing direction and tracking direction) or tilted by controlling the current to the focusing coil, tracking coil, and tilting coil 109. be able to. As a result, the laser beam can be correctly focused on the track on the recording surface of the optical disk.

JP 2000-149292 A

  By the way, in an optical disc apparatus that records and reproduces an optical disc such as a Blu-ray disc, the distance between the disc recording surface and the objective lens is shorter than an optical disc device that reproduces or records and reproduces an optical disc such as a conventional CD or CD-R. . In addition, an optical disc such as a Blu-ray disc has a lead-in area up to the inner periphery side of the disc as compared with an optical disc such as a CD. For this reason, in an optical disc apparatus compatible with a Blu-ray disc or the like, the optical pickup device must be able to move closer to the disc recording surface than in the prior art and be able to move to the inner circumference side of the optical disc.

  However, in order to further move the optical pickup device to the innermost peripheral side of the optical disk, there is a problem that the optical pickup device has to be downsized as compared with an optical pickup device such as a CD. This is because when a conventional optical pickup device is used, a part of the optical pickup device, for example, the lens holder comes into contact with the outer periphery of the turntable (not shown) on the innermost peripheral side of the optical disc. This is because it is impossible to read the disk information on the inner circumference side and write to the area.

  Such a problem will be described in the conventional objective lens driving device 100. In the objective lens driving apparatus 100, the suspension wires 108a and 108b are arranged in parallel in the horizontal direction on the upper portion 107a of the lens holder 101 as described above.

  For this reason, the upper part 107a which fixes suspension wire 108a, 108b protrudes greatly in the turntable direction. When the optical pickup device moves to the innermost peripheral side of the optical disc, the protrusion of the upper portion 107a narrows a necessary clearance between the lens holder 101 and the turntable. For this reason, when used in an optical disc apparatus applied to a Blu-ray disc or the like, the lens holder 101 of the objective lens driving device 100 comes into contact with the turntable. In order to avoid this contact, the lens holder 101 of the objective lens driving device 100 must be further downsized. However, such downsizing makes it difficult to manufacture and causes an increase in manufacturing cost. There was a point.

  Further, the suspension wire 108b itself located on the turntable direction side also causes the clearance between the suspension wire 108b and the turntable to be narrowed when the optical pickup device moves to the innermost peripheral side of the optical disk.

  In view of the above problems, the present invention provides an optical pickup device that can sufficiently secure a clearance between the optical pickup device and the turntable when the optical pickup device moves to the innermost peripheral side of the optical disk. Objective.

  In order to achieve the above object, an optical pickup device of the present invention includes an optical base capable of moving along the radial direction of an optical disc, an objective lens driving device mounted on the optical base, and the optical base. A laser light source that emits laser light, a photodetector that detects the laser light reflected by the optical disc, and a laser beam that guides the laser light emitted from the laser light source to the optical disc and is reflected by the optical disc. In the optical pickup device comprising an optical system that guides the light to the photodetector, the objective lens driving device holds the objective lens that focuses the laser light emitted from the laser light source onto the optical disc, and the objective lens Lens holder and a pair of first suspensions each supporting the lens holder on both sides thereof Wire, a second suspension wire, a third suspension wire, and a damper base that supports the first, second, and third suspension wires, and one end side of each of the two first suspension wires is the lens holder. The upper ends of the two sides of the lens holder are respectively supported, the other ends thereof are supported by the damper base, and the one end sides of the two second and third suspension wires respectively support the lower portions of the both sides of the lens holder. The other end side is supported by the damper base, the actuator coil is wound around the lens holder and between the first suspension wire and the second and third suspension wires. It is characterized by.

  Furthermore, in the optical pickup device of the present invention, the actuator coil is any one of a focusing coil, a tilting coil, and a tracking coil, and each of the tilting coil, the focusing coil, and the tracking coil includes the first coil. Current is preferably supplied from each of the first, second and third suspension wires.

  Furthermore, in the optical pickup device of the present invention, a first support portion is provided on the upper part of each side of the lens holder in order to support the one end side of the first suspension wire, and the second and third suspension wires have the first support portion. In order to support one end side, a second support part is provided at the lower part of both side parts of the lens holder, and the first support part and the second support part are disposed independently of each other with a space therebetween. It is preferable that the focusing coil is wound between the first support portion and the second support portion.

  Furthermore, in the optical pickup device of the present invention, it is preferable that a cross-sectional area of each wire of the first suspension wire is larger than a cross-sectional area of each wire of the second and third suspension wires.

  Furthermore, in the optical pickup device of the present invention, the first, the second suspension moment of the first suspension wire is the same as the sum of the second moments of the second and third suspension wires. It is preferable that a cross-sectional area of each of the second and third suspension wires is set.

  In the optical pickup device of the present invention, it is preferable that the first support portion and the second support portion are formed integrally with the lens holder.

  According to the first aspect of the present invention, since the upper portions on both sides of the lens holder are supported by a pair of first suspension wires, only one suspension wire exists on the upper portions of the side portions. . For this reason, the amount of protrusion in the turntable direction at the upper part of the side portion of the lens holder can be minimized, and the optical pickup device and the turntable are sufficiently separated when the optical pickup device moves to the innermost peripheral side of the optical disk. Secure clearance. Therefore, it is not necessary to reduce the size of the lens holder, and the manufacturing cost of the optical pickup device can be reduced.

  According to the third aspect of the present invention, since the first support portion and the second support portion are disposed independently of each other at a distance from each other on the side portion of the lens holder, the first support portion and the second support portion are provided. A space for winding the focusing coil can be secured. Therefore, the winding operation of the focusing coil can be facilitated, and the manufacturing cost of the optical pickup device can be reduced.

  According to the invention of claim 4, the cross-sectional area of each wire of the first suspension wire is larger than the cross-sectional area of each wire of the second and third suspension wires. Therefore, as described in claim 5, the first, second, and second moments of the first suspension wire are equal to the sum of the sectional moments of the second and third suspension wires. And the cross-sectional area of each wire of the third suspension wire can be set. Thereby, it is possible to balance the sum of the sectional moments of the first suspension wire and the sum of the sectional moments of the second and third suspension wires. Thereby, by matching the moment of the upper part of the lens holder and the moment of the lower part of the lens holder, the lens holder can be mechanically stabilized and accurate and precise driving can be realized.

  According to the sixth aspect of the present invention, the first support portion and the second support portion are formed integrally with the lens holder, so that the lens holder can be easily molded.

  Hereinafter, embodiments of an optical pickup device according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a perspective view showing an overall configuration of an optical pickup device 1 according to an embodiment of the present invention. The optical pickup device 1 includes an optical base 11 that can move along the radial direction of an optical disk (not shown), an objective lens driving device 10 that is mounted on the optical base 11, and a laser that emits laser light. A light source 12, a photodetector 13 that detects laser light reflected by the optical disk, and an optical system that guides the laser light emitted from the laser light source 12 to the optical disk and guides the laser light reflected by the optical disk to the photodetector 13 ( (Not shown).

  The optical pickup device 1 reads information on an optical disc recording surface and writes information on the recording surface as the optical base 11 moves along the radial direction of the optical disc loaded in the optical disc apparatus. .

  FIG. 2 is a perspective view showing the overall configuration of the objective lens driving device 10 of the optical pickup device 1 according to the embodiment of the present invention. The objective lens driving device 10 includes a lens holder 2, a damper base 3, a yoke 4, suspension wires (tilting wires 51 and 52, focusing wires 53 and 54, and tracking wires 55 and 56) (see FIG. 3), It has.

  As shown in FIGS. 2 to 4, the lens holder 2 includes a lens holder main body 21, an objective lens 22, a focusing coil 23, tracking coils 241 to 244, and tilting coils 251 to 254. The focusing coil 23, the tracking coils 241 to 244, and the tilting coils 251 to 254 constitute an actuator coil of the objective lens driving device 10.

  The lens holder body 21 has a substantially rectangular shape and is disposed on the yoke 4. The lens holder main body 21 is supported by the suspension wire (tilting wires 51 and 52, focusing wires 53 and 54, and tracking wires 55 and 56) so as to be displaceable with respect to the yoke 4. On the bottom surface of the lens holder main body 21, a circular hole (not shown) provided below the objective lens 22, which will be described later, and two rectangular through holes 211, 212 through which yoke pieces 431-434 described later pass. And.

  The objective lens 22 is fixed at the center of the upper surface of the lens holder main body 21, and converges the laser light emitted from the laser light source 12 on the recording surface of the optical disk (not shown) and reflects the laser light on the recording surface of the optical disk. Pass through.

  The focusing coil 23 is a rectangular coil, and passes through a magnetic field formed between a magnet 44 and yoke pieces 431 and 432, which will be described later, and between a magnet 45 and yoke pieces 433 and 434. It is wound around the holder body 21 (side surface outer periphery). As shown in FIG. 4, when viewed from the side of the lens holder 2, the focusing coil 23 includes a tilting wire 51 (52) (first suspension wire) and a focusing wire 53 (54) (second suspension), which will be described later. Wire) and the tracking wire 55 (56) (third suspension wire). More specifically, the focusing coil 23 is wound between a first support portion 61 and a second support portion 62 described later around the lens holder main body 21. Further, the lead wire ends of the focusing coil 23 are respectively wound around connection protrusions 64 described later, and are electrically connected to the focusing wires 53 and 54.

  Thus, the focusing coil 23 is disposed in a magnetic field formed between the magnet 44 and the yoke pieces 431 and 432 and between the magnet 45 and the yoke pieces 433 and 434. Therefore, by supplying the current to the focusing coil 23, the entire lens holder 2 can be moved up and down along the focusing direction (reference F direction shown in FIG. 2).

  As shown in FIG. 2, the tracking coil is composed of four tracking coils 241 to 244. Two of these tracking coils 241 to 244 are provided between the focusing coil 23 and the magnets 44 and 45, and two tracking coils are provided on both side surfaces of the lens holder main body 21 in the tangential direction (Tg direction shown in FIG. 2). It is fixed to install. Further, the lead wire ends of the tracking coils 241 to 244 are wound around connection protrusions 65, which will be described later, and are electrically connected to the tracking wires 55 and 56, respectively. Each of the tracking coils 241 to 244 is disposed in a magnetic field formed between the magnet 44 and the yoke pieces 431 and 432 and between the magnet 45 and the yoke pieces 433 and 434. Therefore, the current supply to the tracking coils 241 to 244 allows the entire lens holder 2 to move left and right along the tracking direction (reference numeral Tr direction shown in FIG. 2).

  As shown in FIG. 3, the tilting coil is composed of four tilting coils 251 to 254. These tilting coils 251 to 254 are between the focusing coil 23 and yoke pieces 431 to 434 described later, and are within two rectangular through holes 211 and 212 formed on the bottom surface of the lens holder main body 21. Two pieces are fixed on the circumferential surface. Further, the lead wire ends of the tilting coils 251 to 254 are wound around connection protrusions 63 described later, and are electrically connected to the tilting wires 51 and 52. The tilting coils 251 to 254 are arranged in a magnetic field formed between the magnet 44 and the yoke pieces 431 and 432 and between the magnet 45 and the yoke pieces 433 and 434. Therefore, by supplying current to the tilting coils 251 to 254, the entire lens holder 2 can be rotated around an axis parallel to the tangential direction (the reference numeral Tg direction in FIG. 2).

  The damper base 3 is disposed on one side of the lens holder 2 and includes a damper base main body 31 and a wire support portion 32. Since the damper base 3 is fixed to the yoke 4, the lens holder 2 can also be moved (moving in the focusing direction and tracking direction) or tilted with respect to the damper base 3.

  The damper base body 31 is disposed at a predetermined interval from the lens holder 2 in the tangential direction (Tg direction), and is screwed onto the bottom plate portion 41 of the yoke 4 described later by screws 33 (see FIG. 2). ).

  The wire support portions 32 are provided integrally with the damper base body 31 on both sides of the damper base body 31 in the tracking direction (Tr direction). Each wire support portion 32 includes an upper through hole 323 through which the tilting wire 51 (52) is inserted, and lower through holes 324 and 325 through which the focusing wire 53 (54) and the tracking wire 55 (56) are inserted, respectively. I have. Each wire support portion 32 supports the tilting wire 51 (52), the focusing wire 53 (54), and the tracking wire 55 (56) via a damping material 322, respectively. Two filling recesses 321 for filling the damping material 322 are provided above and below each wire support portion 32. The damping material 322 prevents the resonance of the lens holder 2 caused by the tilting wires 51 and 52, the focusing wires 53 and 54, and the tracking wires 55 and 56 when the entire lens holder 2 moves or tilts.

  As shown in FIGS. 2 and 4, the yoke 4 includes a bottom plate portion 41, two magnet attachment portions 421 and 422, four yoke pieces 431 to 434, and two magnets 44 and 45. I have.

  As described above, the damper base body 31 is fixed to the upper surface of the bottom plate portion 41.

  As shown in FIG. 2, the magnet attachment portion 421 is erected on the bottom plate portion 41 so as to be positioned between the lens holder 2 and the damper base 3. The magnet attachment portion 422 is erected on the bottom plate portion 41 so that the lens holder 2 is positioned between the magnet attachment portion 421 and the magnet attachment portion 422. These magnet mounting portions 421 and 422 have a substantially U-shaped cross section so as to surround the magnets 44 and 45, respectively.

  The yoke pieces 431 to 434 are erected on the bottom plate portion 41 so as to penetrate the two rectangular through holes 211 and 212 formed in the lens holder main body 21. The yoke pieces 431 and 432 are inserted into the through hole 211, and the yoke pieces 433 and 434 are inserted into the through hole 212, respectively. The yoke pieces 431 to 434 are arranged at predetermined intervals from the tilting coils 251 to 254, respectively (see FIG. 3). This prevents the yoke pieces 431 to 434 from contacting the tilting coils 251 to 254 provided on the inner peripheral surfaces of the through holes 211 and 212 of the lens holder 2 when the entire lens holder 2 moves or tilts. Because.

  As shown in FIG. 2, the magnet 44 faces the yoke pieces 431 and 432, forms a magnetic field between the yoke pieces 431 and 432, and the magnet 45 faces the yoke pieces 433 and 434, 45 and the yoke pieces 433 and 434 form a magnetic field.

  The suspension wire includes tilting wires 51 and 52 that are first suspension wires, focusing wires 53 and 54 that are second suspension wires, and tracking wires 55 and 56 that are third suspension wires. The focusing wires 53 and 54 that are the second suspension wires and the tracking wires 55 and 56 that are the third suspension wires are arranged in parallel in the tracking direction (Tr direction).

  One end side of each of the tilting wires 51 and 52 supports the left and right first support portions 61 and 61 (upper side portions) of the lens holder 2, respectively, and the other end side thereof supports the wire support portion 32 of the damper base 3. The upper through-hole 323 is penetrated. The tilting wires 51 and 52 allow the entire lens holder 2 to be moved or tilted by elastically deforming a portion extending between the first support portion 61 and the above-described filling recess 321. Furthermore, in order to make the sum of the sectional moments of the tilting wires 51 and 52 the same as the sum of the sectional moments of the focusing wires 53 and 54 and the tracking wires 55 and 56, each of the tilting wires 51 and 52 The cross-sectional area of the wires is set to have a cross-sectional area larger than the cross-sectional areas of the focusing wires 53 and 54 and the tracking wires 55 and 56.

  One end side of each of the focusing wires 53, 54 supports the left and right second support portions 62, 62 (lower side portions) of the lens holder 2, and the other end side of each of the focusing wires 53, 54 is the wire support portion 32 of the damper base 3. It penetrates the lower through hole 324. The focusing wires 53 and 54 allow the entire lens holder 2 to be moved or tilted by elastically deforming a portion extending between the second support portion 62 and the above-described filling recess 321.

  One end side of each of the tracking wires 55 and 56 supports the left and right second support portions 62 of the lens holder 2, and the other end side thereof is inserted through the lower through hole 325 of the wire support portion 32 of the damper base 3. Yes. The tracking wires 55 and 56 are arranged in parallel with the focusing wires 53 and 54 in the tracking direction (Tr direction), respectively (see FIG. 3). The tracking wires 55 and 56 enable movement or tilting of the entire lens holder 2 by elastically deforming a portion extending between the second support portion 62 and the above-described filling recess 321.

  The other ends of the tilting wires 51 and 52, the focusing wires 53 and 54, and the tracking wires 55 and 56 are electrically connected to a substrate (not shown) provided on the optical base 11. On both sides of the lens holder 2, the above-described first support portions 61, 61 are integrally provided on the upper portion (upper side portion), and the above-described second support portions 62, 62 are integrally provided on the lower portion (lower side portion). .

  The 1st support part 61 and the 2nd support part 62 are mutually independently arrange | positioned at intervals up and down. Accordingly, the focusing coil 23 can be wound between the first support portion 61 and the second support portion 62 at the side portion of the lens holder 2.

  Further, the connection protrusions 63 to 65 described above are disposed on both sides of the lens holder 2 at positions spaced from the first support portions 61 and 61 and the second support portions 62 and 62 to the side opposite to the damper base 3. It is provided integrally.

  The first support portion 61 is formed integrally with the lens holder main body 21 so as to protrude outward from the upper part of both side portions of the lens holder main body 21 in the tracking direction (Tr direction). Each first support portion 61 has a through hole 611 for penetrating one end side of the aforementioned tilting wires 51 and 52. By filling each through hole 611 with a damping material, one end side of the tilting wires 51 and 52 is held.

  The second support portion 62 is formed integrally with the lens holder main body 21 so as to protrude outward from the lower portions of both side portions of the lens holder main body 21 in the tracking direction (Tr direction). Each of the second support parts 62 has through holes 621 and 622 for allowing the one end side of the focusing wire 53 (54) and the tracking wire 55 (56) to pass through. That is, the through hole 621 and the through hole 622 are arranged in parallel in the tracking direction (Tr direction). By filling the through holes 621 and 622 with a damping material, one end sides of the focusing wires 53 and 54 and the tracking wires 55 and 56 are held.

  As described above, the lead ends of the tilting coils 251 to 254 are wound around the connection protrusion 63. One end of the tilting wires 51 and 52 penetrating the first support portion 61 and extending to the connection protrusion 63 is electrically connected to the lead wire ends of the tilting coils 251 to 254 at the connection protrusion 63. Therefore, current is supplied to the tilting coils 251 to 254 by the tilting wires 51 and 52.

  As described above, the lead wire end of the focusing coil 23 is wound around the connection protrusion 64. One ends of the focusing wires 53 and 54 that pass through the second support portion 62 and extend to the connection protrusions 64 are electrically connected to the lead wire ends of the focusing coil 23 at the connection protrusions 64. Accordingly, current is supplied to the focusing coil 23 by the focusing wires 53 and 54.

  As described above, the lead ends of the tracking coils 241 to 244 are wound around the connection protrusion 65. One ends of the tracking wires 55 and 56 extending through the second support portion 62 and extending to the connection protrusion 65 are electrically connected to the lead wire ends of the tracking coils 241 to 244 at the connection protrusion 65. Accordingly, current is supplied to the tracking coils 241 to 244 by the tracking wires 55 and 56.

Next, the effect of this embodiment is demonstrated.
First, the operation of the lens holder 2 will be described. As described above, the lens holder 2 is provided with focusing wires 53 and 54, tracking wires on the damper base 3 so as to move or tilt with respect to the yoke 4 provided with the magnets 44 and 45 and the yoke pieces 431 to 434. 55 and 56 and tilting wires 51 and 52 are supported. Therefore, when the current supply by the focusing wires 53 and 54, the tracking wires 55 and 56, and the tilting wires 51 and 52 is controlled, the focusing coil 23, the tracking coils 241 to 244, and the tilting coils 251 to 254 cause the magnetic field described above to The lens holder 2 provided with the focusing coil 23, the tracking coils 241 to 244, and the tilting coils 251 to 254 is moved or tilted with respect to the yoke 4 because the focusing coil 23, the tracking coils 241 to 244 and the tilting coils 251 to 254 are provided. Become.

  According to the present embodiment, the tilting wires 51 and 52 are supported one by one on the first support portions 61 and 61 provided on both side upper portions of the lens holder main body 21, respectively. Therefore, the protrusion amount of the first support portion 61 from the lens holder body 21 in the turntable (not shown) direction, that is, the tracking direction (Tr direction) can be minimized. Therefore, when the optical pickup device 1 moves to the innermost peripheral side of the optical disc (not shown), a sufficient clearance between the optical pickup device 1 and the turntable (not shown) can be ensured. Therefore, it is not necessary to reduce the size of the lens holder main body 21 in order to ensure this clearance, so that an increase in manufacturing cost of the optical pickup device 1 can be avoided.

  Further, since the first support portion 61 and the second support portion 62 are arranged independently at an interval in the vertical direction on the side portion of the lens holder main body 21, the first support portion 61 and the second support portion 61 are provided. The focusing coil 23 can be wound between the two. Therefore, the winding operation of the focusing coil 23 can be facilitated, and the manufacturing cost can be reduced through the reduction of the operation time.

  Furthermore, the cross-sectional areas of the tilting wires 51 and 52 are larger than the cross-sectional areas of the focusing wires 53 and 54 and the tracking wires 55 and 56. Therefore, the tilting wires 51, 52 and the focusing wires 51, 52 are focused so that the sum of the sectional moments of the tilting wires 51, 52 is the same as the sum of the sectional moments of the focusing wires 53, 54 and the tracking wires 55, 56. The cross-sectional areas of the wires 53 and 54 and the tracking wires 55 and 56 can be set. Thereby, a balance can be taken between the sum of the sectional moments of the tilting wires 51 and 52 and the sum of the sectional moments of the focusing wires 53 and 54 and the tracking wires 55 and 56. Therefore, by matching the moment of the upper part of the lens holder 2 with the moment of the lower part of the lens holder 2, the lens holder 2 can be mechanically stabilized and an accurate and precise drive can be realized.

  The combination of each coil and each suspension wire in the above embodiment is an example, and the combination can be changed as appropriate. For example, the first suspension wire is a focusing wire electrically connected to the focusing coil, the second suspension wire is a tracking wire electrically connected to the tracking coil, and the third suspension wire is a tilting coil. It may be a tilting wire electrically connected to. In this case, the cross-sectional area of each wire of the focusing wire is larger than the cross-sectional area of each wire of the tracking wire and tilting wire, and as described above, the total of the secondary moments of the cross-section of the focusing wire is the tracking wire and tilting wire. It is desirable to be the same as the sum of the moments of section of the wire and wire.

1 is a perspective view showing an overall configuration of an optical pickup device according to an embodiment of the present invention. It is a perspective view which shows the whole structure of the objective lens drive device shown in FIG. It is a top view of the objective lens drive device shown in FIG. It is a side view of the objective lens drive device shown in FIG. It is sectional drawing of the conventional objective lens drive device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical pick-up apparatus 10 Objective lens drive device 11 Optical base 12 Laser light source 13 Photo detector 2 Lens holder 21 Lens holder main body 211, 212 Rectangular through-hole 22 Objective lens 23 Focusing coils 241 to 244 Tracking coils 251 to 254 Tilting coils 3 damper base 31 damper base body 32 support portion 321 filling recess 322 damping material 323 upper through hole 324, 325 lower through hole 33 screw 4 yoke 41 bottom plate portion 421, 422 magnet mounting portion 431-434 yoke piece 44, 45 magnet 51 , 52 Tilting wires 53, 54 Focusing wires 55, 56 Tracking wire 61 First support portion 611 Through hole 62 Second support portions 621, 622 Through holes 63-65 Connection protrusion 100 Objective lens drive Device 101 Lens holder 102 Objective lens 106c, 106d Tilt magnets 107a, 107b Upper 107c, 107d Lower 108a-108e Suspension wire 109 Tilting coil

Claims (6)

An optical base capable of moving along the radial direction of the optical disc;
An objective lens driving device mounted on the optical base;
A laser light source that is provided on the optical base and emits a laser beam; and a photodetector that detects the laser beam reflected by the optical disc;
In an optical pickup device comprising: an optical system that guides laser light emitted from the laser light source to the optical disc and guides laser light reflected by the optical disc to the photodetector;
The objective lens driving device includes an objective lens for condensing laser light emitted from the laser light source on an optical disc, a lens holder for holding the objective lens, and two lens holders each supporting the lens holder on both sides thereof. A pair of first suspension wires, second suspension wires, third suspension wires, and a damper base for supporting the first, second, and third suspension wires, each one end of the two first suspension wires The side supports upper portions of both side portions of the lens holder, the other end sides thereof are supported by the damper base, and one end sides of the two second and third suspension wires respectively are both sides of the lens holder. The lower end of the part is supported, and the other end side thereof is supported by the damper base, and the lens A surrounding holder, and the first suspension wire, an optical pickup device characterized by a coil actuator wound between said second and third suspension wires. The actuator coil is one of a focusing coil, a tilting coil, and a tracking coil,
2. The optical pickup device according to claim 1, wherein a current is supplied to each of the tilting coil, the focusing coil, and the tracking coil from each of the first, second, and third suspension wires. In order to support the one end side of the first suspension wire respectively, a first support portion is provided on the upper part of each side of the lens holder,
In order to support the one end side of the second and third suspension wires, a second support part is provided at the lower part of both side parts of the lens holder,
The first support part and the second support part are disposed independently of each other with a space therebetween,
The optical pickup device according to claim 2, wherein the focusing coil is wound between the first support portion and the second support portion.   The optical pickup device according to claim 1, wherein a cross-sectional area of each wire of the first suspension wire is larger than a cross-sectional area of each wire of the second and third suspension wires.   Each wire of the first, second, and third suspension wires is such that the sum of the cross-sectional secondary moments of the first suspension wire is the same as the sum of the cross-sectional secondary moments of the second and third suspension wires. The optical pickup device according to claim 1, wherein the cross-sectional area is set. The optical pickup device according to claim 3, wherein the first support part and the second support part are formed integrally with the lens holder.

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