JP4982821B2 - Lens drive device - Google Patents

Description

  The present invention relates to a lens driving device for an optical pickup device, and more particularly to a lens driving device that is easy to manufacture.

  An optical pickup device capable of recording and / or reproducing information with respect to an optical disk represented by a CD or a DVD has been developed. In addition, an optical pickup device capable of recording / reproducing information on an optical disk such as a Blu-ray Disc or an HD DVD using a blue-violet semiconductor laser having a wavelength of about 400 nm has been rapidly developed. Here, in the objective lens for forming the condensing spot in the optical pickup device, a focusing operation for appropriately forming the condensing spot on the information recording surface of the optical disc at the time of recording and / or reproducing information, and the optical disc And a tracking operation to properly follow the track. In addition to these operations, in addition to these operations, a tilt adjustment operation for adjusting the tilt of the objective lens to correct aberrations is often performed in order to cope with the high-speed recording / reproduction of a DVD that has been increasing in recent years. ing. In addition, in the case of HD DVD, since the substrate thickness is relatively large and the numerical aperture is increased, it is more important to perform the tilt adjustment operation with high accuracy.

Patent Document 1 discloses a lens driving device that supports a lens holder so that a focusing operation, a tracking operation, and a tilt adjustment operation can be performed by a total of four wire-like suspension members, two on each side. The suspension member has a function of elastically supporting the lens holder and a function of supplying electric power to the coil in order to generate a magnetic force necessary for each operation.
JP 2005-216357 A

  However, for example, an optical pickup device mounted on a notebook personal computer or the like is required to have a thickness of about 5 to 10 mm. In order to mount on such an optical pickup device, there is a problem that it is difficult to solder the suspension member by simply making the lens driving device of Patent Document 1 compact as it is, and some device is desired.

  The present invention has been made in view of such problems, and an object thereof is to provide a lens driving device that can be mounted on a thin optical pickup device.

The lens driving device according to claim 1 is a lens driving device for an optical pickup device,
A movable holder for holding the lens;
A plurality of conductive wires attached to the base at one end side;
A holder substrate for fixing the other end of the wire to the holder;
The holder substrate has a plurality of conductive surfaces for soldering the wire, and at least one conductive surface has a distance to the farthest position in both directions perpendicular to the axis of the wire to be soldered to the holder substrate. Are different from each other ,
Another conductive surface of the one conductive surface close to the distant position, wherein the other conductive surface to which the wire adjacent to the wire to be soldered to the one conductive surface is soldered is The first conductive surface is shifted in a direction along the axis of the wire .

  According to the lens driving device of the present invention, the holder substrate has a plurality of conductive surfaces for soldering the wire, and at least one conductive surface is perpendicular to the axis of the wire to be soldered thereto. In this case, the distance to the farthest position is different from each other. Therefore, when the wire is soldered to the conductive surface, it is possible to prevent the soldering iron from hitting the wire and inhibiting the soldering operation. Even if the area of the surface is small, a wide area for soldering will be secured, so that the wire can be soldered easily in a short time while suppressing the dimensions of the holder substrate. It is suitable for mounting on a thin optical pickup device.

  A lens driving device according to a second aspect is the lens driving device according to the first aspect, wherein the conductive surface has a length in a direction along the wire that is shorter than a length in a direction perpendicular to the wire. Therefore, the holder substrate can be made more compact.

  According to a third aspect of the present invention, in the lens driving device according to the first or second aspect, the adjacent conductive surfaces are arranged so that the distances from the positions where the wires are fixed to the base are different. Therefore, the holder substrate can be made compact and thin.

  According to a fourth aspect of the present invention, there is provided the lens driving device according to the third aspect, wherein the holder substrate fixes the wire between the conductive surface and a fixing position on the base side of the wire. When the holder is tilted for tilt adjustment or the like, for example, the length of the plurality of wires is equal between the support portion and the fixed position. , Malfunction due to fulcrum misalignment can be suppressed.

  According to a fifth aspect of the present invention, in the lens driving device according to the fourth aspect, the support portion is a conductive surface, and the wire is fixed to the support portion using a conductive member. Therefore, in addition to the conduction between the wire and the conductive surface, it is possible to ensure a defect such as a contact failure by ensuring the conduction between the wire and the support portion. Note that the wire may be fixed to the support portion using a member having a damping property, thereby improving the vibration characteristics of the wire.

  A lens driving device according to a sixth aspect of the present invention is the lens driving device according to the fourth aspect, wherein the wire is fixed to the support portion using an adhesive, so that, for example, an epoxy UV curing adhesive Can be easily fixed, and the wire fulcrum can be formed while suppressing shrinkage during curing.

  A lens driving device according to a seventh aspect is the lens driving device according to any one of the first to sixth aspects, wherein the holder is driven by a coil in a magnetic circuit, and the wire supplies power to the coil. An elastic force corresponding to the biasing force of the coil is generated.

  ADVANTAGE OF THE INVENTION According to this invention, the lens drive device which can be mounted in a thin optical pick-up apparatus can be provided.

  Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 is a perspective view of a lens driving device according to the present embodiment. A plate-like base 1 that also serves as a yoke is fixed to a housing of an optical pickup device (not shown). A housing 2 is fixed on the base 1. A base substrate 3 is attached to the front side of the housing 2 in the figure. One end of a total of six wires 4, three on each side, is fixed to the base substrate 3, and the wires 4 on each side are aligned in parallel in the vertical direction and extend along the base 1. Exist. The other end of the wire 4 is soldered to the side surface of the holder 5 via a holder substrate 14 made of glass epoxy. The wire 4 has a function of movably supporting the holder 5 with respect to the base 1 and a function of supplying power to a coil to be described later from the base substrate 3 to which a wiring (not shown) is connected. The casing 2 is filled with a gel (not shown) having a damping effect for the wire 4.

  The resin holder 5 has a substantially pentagonal plate shape, and an objective lens 6 is mounted in a circular opening (not shown) on the back side in the drawing. This objective lens 6 is used for condensing a laser beam on an information recording surface of an optical disk in an optical pickup device. Further, the holder 5 has two rectangular openings 5a and 5b on the front side in the figure, and further has a balancer 5c adjacent to the rectangular openings 5a and 5b. Note that the holder 5 is connected between the objective lens 6 side and the opposite side with pillar portions 5d and 5e arranged on both sides of the rectangular opening 5a, and pillars arranged on both sides of the rectangular opening 5b. It can be said that it is connected with the parts 5e and 5f. With such a configuration, the rigidity of the holder 5 can be ensured to be high even if the rectangular openings 5a and 5b have a relatively large cross-sectional area. In addition, when the central axis of the central column portion 5e intersects the optical axis of the objective lens 6 (including its extension line), a good balance of the holder 5 can be obtained.

  In the rectangular opening 5a, a pair of magnets 9A and 10A backed by the yokes 7A and 8A are disposed opposite to each other. The first coil group G1 (inner coil 12A and outer coil 13A) is arranged so as to wind around the magnet 9A and the yoke 7A. Between the first coil group G1 and the magnet 10A, a tracking coil 11A wound so that the first coil group G1 and the winding axis are orthogonal to each other is disposed.

  On the other hand, in the rectangular opening 5b, a pair of magnets 9B and 10B backed by the yokes 7B and 8B are disposed opposite to each other. The second coil group G2 (inner coil 12B and outer coil 13B) is arranged so as to wind around the magnet 9B and the yoke 7B. Between the second coil group G2 and the magnet 10B, a tracking coil 11B wound so that the second coil group G2 and the winding axis are orthogonal to each other is disposed. The first coil group G1 is attached to the rectangular opening 5a via a holding body 15A that holds both sides thereof, and the second coil group G2 is attached to the rectangular opening 5b via a holding body 15B that holds both sides thereof. It has been.

  FIG. 2 is a view of the holder substrate 14 shown in FIG. 1 as viewed in the direction of arrow II. Hereinafter, only the right holder substrate 14 will be described, but the configuration is the same except that the left holder substrate 14 also has a mirror image relationship. In FIG. 2, a plate-like holder substrate 14 is soldered to the glass epoxy base 14a bonded to the holder 5 and the ends of the three wires 4 arranged in parallel in the vertical direction in FIG. Conductive surfaces 14b, 14c, and 14d, support portions 14e, 14f, and 14g that support the wires 4, and terminal portions 14h, 14i, and 14j that connect the wirings H1, H2, and H3 from the coils described above.

  The holder substrate 14 has a corner portion cut out in an arc shape to form a relief portion 14x. By using this space, an unnecessary portion of the wire 4 can be easily cut short. The rectangular conductive surfaces 14b, 14c, and 14d in which the horizontal length along the wire 4 is shorter than the vertical length orthogonal to the wire 4 are the positions of the adjacent conductive surfaces in the horizontal direction. By making them different, they are arranged in a so-called staggered pattern. In addition, the center line of the upper conductive surface 14b in FIG. 2 is arranged to be shifted toward the center of the holder substrate 14 with respect to the axis of the wire 4 to be soldered thereto, that is, the conductive surface 14b is soldered thereto. The distance x1 from the axis of the wire 4 to the farthest position in the vertical direction (upward in FIG. 2) is the farthest position from the axis of the wire 4 in the vertical direction (downward in FIG. 2) It is smaller than the distance x2. On the other hand, the center line of the lower conductive surface 14d in FIG. 2 is arranged to be shifted toward the center of the holder substrate 14 with respect to the axis of the wire 4 to be soldered thereto. That is, in the conductive surface 14d, the distance y1 from the axis of the wire 4 soldered to the farthest position in the vertical direction (downward in FIG. 2) is the vertical direction (FIG. 2) from the axis of the wire 4. And the distance y2 to the farthest position toward the upper side). With the above configuration, the vertical dimension of the holder substrate 14 can be suppressed. The center line of the central conductive surface 14c coincides with the axis of the wire 4 soldered thereto, but may be similarly shifted in either direction.

  On the other hand, the conductive support portions 14e, 14f, and 14g are arranged in a line along the vertical direction orthogonal to the horizontal direction in which the wires 4 extend, and are electrically connected to the conductive surfaces 14b, 14c, and 14d on the holder substrate 14, respectively. And are electrically connected to the terminal portions 14h, 14i, and 14j, respectively. The terminal portions 14h, 14i, and 14j are connected to wirings H1 to H3 from the tracking coil 11A or 11B, the focusing coil 13A or 13B, and the tilt adjustment coil 12A or 12B.

  When the wires 4 are soldered to the conductive surfaces 14b and 14d, as shown by dotted lines, the solder material SW and the soldering iron T are brought closer to the wires 4 from the center. In the case of the conductive surface 14c, the solder material SW and the soldering iron T may be approximated from any direction. The solder SD melted from the solder material SW by the soldering iron T is solidified on the conductive surface, and the wire 4 can be fixed to be conductive.

  According to the present embodiment, since the center lines of the conductive surfaces 14b and 14d are deviated from the axis of the wire 4 to be soldered thereto, the soldering iron T hits the wire 4 and obstructs the soldering operation. Therefore, even if the areas of the conductive surfaces 14b and 14d are small, a wide area for soldering is ensured, and thereby the wire 4 can be easily and quickly formed while suppressing the dimensions of the holder substrate 14. Therefore, it is suitable for mounting on a thin optical pickup device.

  However, only by soldering the wire 4 to the conductive surfaces 14b, 14c, and 14d arranged in a staggered manner, the length from the base of the wire 4 to the support point is different, and for example, the balance at the time of tilt adjustment is deteriorated. There is a fear. Therefore, each wire 4 is fixed to the support portions 14e, 14f, 14g arranged in a line, and by using this as a support point, the length from the base of the wire 4 to the support point is made equal, thereby Balance is maintained during tilt adjustment. Here, when each wire 4 is fixed to the support portions 14e, 14f, and 14g, if an epoxy UV curing adhesive SC is used, the wire 4 can be easily fixed and the shrinkage at the time of curing can be suppressed and the wire fulcrum can be formed. . Further, when a plurality of places are soldered on the wire 4, there is a possibility that heat transfer occurs to the already solidified solder through the wire 4, which may cause melting and misalignment, but such a problem can be avoided. Furthermore, if the wire 4 is bonded to the support portions 14e, 14f, 14g before the wire 4 is soldered to the conductive surfaces 14b, 14c, 14d, the soldering workability is improved. On the other hand, when the solder 4 is used to fix the wires 4 to the support portions 14e, 14f, and 14g, the conductivity between the wires 4 and the wirings H1 to H3 is increased, and supplied from the outside via the wires 4. The transmitted electric power can be effectively transmitted to each coil, and the difficulty of soldering work can be reduced. On the other hand, if each wire 4 is fixed to the solder support portions 14e, 14f, and 14g using an adhesive having a damping property, the vibration characteristics of the holder 5 can be improved.

  FIG. 3 is a view showing a holder substrate 14 ′ according to another embodiment. In this Embodiment, it is set as the structure supported with the wire 4 of one side (a total of four), and the support part to fix is not provided. The conductive surfaces 14b and 14d are connected to terminal portions 14h and 14j that connect the wirings H1 and H3 from the coil. In addition, the escape part 14x which is an arc-shaped notch is formed in the edge part of the base 14a. This is provided so that the base 14a and the wire 4 do not come into contact during the tracking operation. Since other points are the same as those in the above-described embodiment, description thereof is omitted.

  FIG. 4 is a view of the base substrate 3 shown in FIG. 1 as viewed in the direction of arrow IV. In FIG. 4, a plate-like base substrate 3 includes a glass epoxy (or flexible substrate) base 3 a bonded to the housing 2, six holes 3 b that pass through the ends of the wires 4, and a direction perpendicular to the paper surface. 6 includes three conductive surfaces 3c to which the ends of the wires 4 are soldered, and six terminal portions 3d to which wiring (not shown) to which power is supplied from the outside is connected.

  The conductive surface 3c orthogonal to the wire 4 has a dimension in the direction in which the adjacent wires 4 are arranged on one side (vertical direction in FIG. 4) smaller than the dimension in the direction orthogonal to the wire 4 (horizontal direction in FIG. 4). Yes. Further, in the longitudinal direction of the conductive surface 3c (horizontal direction in FIG. 4), the length Δ1 on the side close to the outer edge of the base substrate 3 with respect to the wire 4 is 0.6 mm or more, and the length Δ2 on the opposite side thereof. Is 0.3 mm or more, and Δ1> Δ3.

  When soldering the end portions of the wires 4 to the conductive surfaces 3 c, a solder material (not shown) and a soldering iron are brought close to the wires 4 from the left and right outer edges of the base substrate 3. The solder SD melted from the solder material with the soldering iron is solidified on the conductive surface 3c, and the wire 4 can be fixed to be conductive.

  According to the present embodiment, when the wire 4 is soldered to the conductive surface 3c, it is possible to prevent the soldering iron from coming into contact with the wire 4 and hinder the soldering operation, and thus the area of the conductive surface 3c is reduced. Even if it is small, a wide area for soldering can be secured, so that the wire can be easily soldered in a short time while suppressing the size of the base substrate 3, so that a thin optical pickup can be obtained. It is suitable for mounting on an apparatus. Further, by setting the length Δ1 of the conductive surface 3c to 0.6 mm or more, a wider area for soldering can be ensured even if the area of the conductive surface 3c is small. Further, by setting the length Δ2 of the conductive surface 3c to 0.3 mm or more, the wire diameter of the solder is generally 0.3 mm. Therefore, the solder SW before solidification is soldered with the wire 4 interposed therebetween. It can be approached from the side opposite to T (see dotted line), and workability is improved.

  Next, the operation of the lens driving device according to this embodiment will be described. In FIG. 1, the direction of the magnetic field across the outer coil 13A is the same as the direction of the magnetic field across the outer coil 13B. Here, when power is supplied through the wire 4, current flows through the outer coils 13 </ b> A and 13 </ b> B in the same direction (clockwise in this case) with the same current value. The magnetic force is generated upward in the figure, and the magnetic force upward in the figure is generated in the outer coil 13B. Accordingly, the holder 5 to which the first coil group G1 and the second coil group G2 are fixed moves upward in the drawing, thereby realizing the focusing operation by moving the objective lens 6 in the optical axis direction. Can do. If the direction of the current is reversed, the holder 5 moves downward.

  On the other hand, when a current is passed through the inner coil 12A in the clockwise direction and a current is passed through the inner coil 12B in the counterclockwise direction, the inner coil 12A is Is generated, and the inner coil 12B has a downward magnetic force in the figure. Therefore, a moment acts on the holder 5 around its central axis. Tilt adjustment of the objective lens 6 can be performed by tilting the holder 5 using such moment. 2, the direction of the magnetic field is changed by magnetizing the magnet 10B side of the magnet 9B to the south pole, and magnetizing the magnet 9B side of the magnet 10B to the north pole, and the inner coil 12A, 12B, when the direction of current flow in the outer coil 13A is the same clockwise and the direction of current flow in the outer coil 13B is counterclockwise, while performing the focusing operation by the outer coils 13A and 13B, the clockwise magnetic circuit Is formed, and there is an advantage that the gap magnetic flux density is increased.

  Furthermore, by passing an electric current through the tracking coils 11A and 11B, the holder 5 can be moved together with the objective lens 6 in a direction perpendicular to the optical axis, thereby performing a tracking operation.

  The present invention has been described above with reference to the embodiments. However, the present invention should not be construed as being limited to the above-described embodiments, and can be modified or improved as appropriate.

It is a perspective view of the lens drive device concerning this Embodiment. It is the figure which looked at the holder board | substrate 14 shown in FIG. 1 in the arrow II direction. It is a figure which shows the holder board | substrate 14 'concerning the modification of this Embodiment. It is the figure which looked at the base substrate 3 shown in FIG. 1 in the arrow IV direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base 2 Case 3 Base board 3a Base 3b Hole 3c Conductive surface 3d Terminal part 4 Wire 5 Holder 5a Rectangular opening 5b Rectangular opening 5c Balancer 5d Column 5e Column 5f Column 6 Objective lens 7A Yoke 7B Yoke 9A Magnet 9B 10A magnet 10B magnet 11A tracking coil 11B tracking coil 12A inner coil 12B inner coil 13A outer coil 13B outer coil 14 holder substrate 14a base 14b, 14c, 14d conductive surface 14e, 14f, 14g support portion 14h, 14i, 14j terminal portion 14x escape Part 15A Holder (Adhesive)
15B Holder (Adhesive)
G1 First coil group G2 Second coil group H1-H3 Wiring SC Adhesive (cream solder)
SD Solder SW Solder material

Claims (7)

A lens driving device for an optical pickup device,
A movable holder for holding the lens;
A plurality of conductive wires attached to the base at one end side;
A holder substrate for fixing the other end of the wire to the holder;
The holder substrate has a plurality of conductive surfaces for soldering the wire, and at least one conductive surface has a distance to the farthest position in both directions perpendicular to the axis of the wire to be soldered to the holder substrate. Are different from each other ,
Another conductive surface of the one conductive surface close to the distant position, wherein the other conductive surface to which the wire adjacent to the wire to be soldered to the one conductive surface is soldered is The lens driving device is shifted in a direction along the axis of the wire with respect to the one conductive surface .   The lens driving device according to claim 1, wherein the conductive surface has a length in a direction along the wire that is shorter than a length in a direction orthogonal to the wire.   3. The lens driving device according to claim 1, wherein the adjacent conductive surfaces are arranged so that the distances from a position where the wire is fixed to the base are different. 4.   The holder substrate has a support portion for fixing the wire between the conductive surface and a fixing position on the base side of the wire, and the support portion and the fixing position in the plurality of wires. The lens driving device according to claim 3, wherein the lengths between are equal.   The lens driving device according to claim 4, wherein the support portion is a conductive surface, and the wire is fixed to the support portion using a conductive member.   The lens driving device according to claim 4, wherein the wire is fixed to the support portion using an adhesive.   7. The holder according to claim 1, wherein the holder is driven by a coil in a magnetic circuit, and the wire generates an elastic force corresponding to an urging force of the coil while supplying electric power to the coil. The lens driving device according to any one of the above.

Images