JP2004005841A - Optical pickup device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To adjust the tilt of a lens holder to which an object lens is attached. <P>SOLUTION: A lens holder 14 to which an object lens 13 is attached is supported by each one end of four suspension wires 15, and each other end of the four suspension wires 15 is supported freely swinging at a suspension part 11e provided on an optical base 11. When the tilt angle of the lens holder 14 is adjusted so that the light axis K of the object lens 13 assumes an almost vertical posture relative to a signal plane of an optical disk, each other end of the four suspension wires 15 is previously supported at the upper and lower parts of left and right sides of the suspension part 11e, and then each one end of the four suspension wires 15 is joined by soldering at each tip part end plane 14d1 of four conductive terminals 14d provided so as to protrude upward and downward from the left and right sides of the lens holder 14 so that the light axis K of the object lens 13 assumes an almost vertical posture relative to the signal plane of the optical disk. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
According to the present invention, a lens holder on which an objective lens is mounted on an optical base is swingably supported on a suspension via a plurality of (four) suspension wires, and the objective lens is integrated with the lens holder to an optical disc. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup device that swings in a focus direction and a tracking direction and that can be tilt-adjusted so that an optical axis of an objective lens takes a posture substantially perpendicular to a signal surface of an optical disc.
[0002]
[Prior art]
Optical discs capable of recording and / or reproducing various information signals such as audio signals, video signals, and data signals at a high density use an optical pickup device movably provided in an optical disc drive to move a desired recording track on a signal surface at a high speed. It is frequently used because it can be accessed.
[0003]
At this time, the optical pickup device described above narrows down the laser light emitted from the semiconductor laser with an objective lens to obtain a light spot, irradiates the light spot to a recording track on the signal surface of the optical disk, and The information signal is reproduced by detecting the return light reflected by the reflection film with a photodetector. When an information signal is recorded on the signal surface of the optical disc, a recording light spot having a strong laser power is irradiated onto the signal surface, while when an information signal that has been recorded is reproduced, the laser power is weak. A light spot for reproduction is irradiated on the signal surface.
[0004]
By the way, when recording and / or reproducing information signals on an optical disk, it is preferable that the optical axis of the objective lens with respect to the signal surface of the optical disk is in a state of being exactly perpendicular from the viewpoint of suppressing optical aberration and the like. However, since it is very difficult to secure an accurate vertical state as described above due to an error in assembling the optical pickup, a tilt adjusting mechanism for adjusting the inclination of the optical axis of the objective lens with respect to the optical disk is required. It became so.
[0005]
FIG. 1 is a perspective view showing an optical pickup device provided with an example of a tilt adjusting mechanism in a conventional example.
[0006]
As shown in FIG. 1, in an optical pickup device 10A having a tilt adjustment mechanism as an example in a conventional example, an optical base 11 serving as a base is integrally formed by molding using an insulating resin material. I have. The upper surface 11a of the optical base 11 is formed substantially parallel to the signal surface of the optical disk (not shown), and a guide rail support portion 11b is formed in front of the upper surface 11a so as to be one step lower than the upper surface 11a. A guide rail GR provided in an optical disk drive (not shown) is slidably fitted to the support portion 11b, so that the optical base 11 is integrally formed with a lens holder 14 to which an objective lens 13 described later is attached. It can be moved in the radial direction.
[0007]
A flat surface 12a of a yoke base 12 formed by using a soft magnetic steel plate or the like is mounted on the upper surface 11a of the optical base 11, and a lens having an objective lens 13 mounted above the flat surface 12a. A holder 14 is swingably supported by a suspension 16 via four suspension wires 15 in total, up, down, left and right.
[0008]
More specifically, first, in the above-described yoke base 12, a pair of first yoke portions 12b and 12c are formed by being cut and raised upward from the flat surface 12a before and after the lens holder 14 is sandwiched. A pair of second yoke portions 12d and 12e are cut and raised upward and enter a pair of substantially rectangular through holes 14a and 14b which penetrate the holder 14 before and after the object lens 13 is sandwiched therebetween. ing.
[0009]
Further, a through-hole 12f for passing a laser beam is formed below the objective lens 13 in the flat surface 12a of the yoke base 12. Further, a pair of magnets 17, 17 are fixed inside a pair of first yoke portions 12b, 12c formed on the yoke base 12, and the pair of magnets 17, 17 are connected to a pair of second yoke portions 12d, 12e. , Respectively.
[0010]
Next, the lens holder 14 is made of a resin material having an insulating property and is formed in a small and light rectangular shape, and the objective lens 13 is provided at an upper portion inside a stepped hole for mounting an objective lens (not shown) formed at the center. Are attached by an adhesive or the like, and the focus coil 18 is fixed by an adhesive or the like while being wound along the outer peripheral portion of the rectangular shape. A total of four tracking coils 19 are individually fixed by an adhesive or the like.
[0011]
Next, the suspension 16 is formed in a U-shaped frame shape using a resin material having an insulating property, and the suspension 16 is formed on the yoke base 12 above a flat surface 12 a of the yoke base 12. One of the yoke portions 12b and 12c is fixed to the rear first yoke portion 12c using screws 20.
[0012]
A total of four suspension wires 15 are used in parallel with the signal surface of the optical disc (not shown) between the lens holder 14 and the suspension 16 by using a conductive wire that can be soldered. Are located. Also, one end of each of the four suspension wires 15 is supported by four protrusions 14 c formed to project upward and downward on the left and right side surfaces of the lens holder 14, and the distal end of each of the one end is connected to the lens holder 14. Solder together with the end of the focus coil 18 or the end of the tracking coil 19 to the four conductive pins 21 press-fitted vertically on the left and right sides, and connect each other end opposite to one end side. The suspension 16 is supported up and down on the left and right side surfaces, respectively, and the other end portion is soldered to a wiring board 22 fixed to the rear surface of the suspension 16.
[0013]
When the lens holder 14 is formed using a resin material having heat resistance to soldering, the four conductive pins 21 are not pressed into the upper and lower sides of the left and right side surfaces of the lens holder 14, and the four Four terminals (not shown) are integrally formed with the lens holder 14 on the left and right sides of the lens holder 14 in place of the conductive pins 21, and each terminal has an end of the focus coil 18 or a tracking coil 19. There is also a method in which the ends are pre-entangled and then one end of the suspension wire 15 is soldered together with the end of the focus coil 18 or the end of the tracking coil 19.
[0014]
Therefore, the focus coil 18 and the tracking coil 19 are electrically connected to the wiring board 22 via any one of the four suspension wires 15, and are further connected to the optical base 11 via the four cables 23 from the wiring board 22. A connector (not shown) on the signal source side is electrically connected to a connector circuit board 24 mounted substantially vertically along a side surface 11c substantially orthogonal to the formed guide rail support portion 11b. By connecting to the connector 25, a focus drive current and a tracking drive current are supplied to the focus coil 18 and the tracking coil 19.
[0015]
As a result, when respective drive currents are supplied to the focus coil 18 and the tracking coil 19, a gap between the pair of magnets 17, 17 fixed to the pair of first yoke portions 12b, 12c and the pair of second yoke portions 12d, 12e is obtained. The objective lens 13 attached to the lens holder 14 is swingable in a focus direction FO and a tracking direction TR with respect to an optical disc (not shown) via four suspension wires 15 by a magnetic field generated in the lens holder 14.
[0016]
Further, a leaf spring 26 for tilt adjustment is fixed on a leaf spring support 11d formed to protrude upward on the side surface 11c side of the optical base 11, and downward from a tip end portion of the leaf spring 26 for tilt adjustment. The bent portion 26a formed by bending is always in contact with the flat surface 12a of the yoke base 12. Then, the rear surface of the yoke base 12 is pressed against the urging force of the tilt adjusting leaf spring 26 abutting on the flat surface 12 a of the yoke base 12 by a tilt adjusting screw (not shown) provided on the rear surface of the optical base 11. And lift it up to adjust the tilt so that the optical axis K of the objective lens 13 attached to the lens holder 14 is substantially perpendicular to the signal surface of the optical disc (not shown), and then molded using a resin material. The decorative cover 27 is fitted over the lens holder 14.
[0017]
Although not shown here, a semiconductor laser that emits laser light toward the objective lens 13 and a laser light from the semiconductor laser are applied to the back of the optical base 11 by the objective lens 13 via a beam splitter. There is provided a photodetector for irradiating the light spot obtained by the narrowing down to the signal surface of the optical disk, detecting the return light reflected by the reflection film on the signal surface through the objective lens 13 and the beam splitter, and reproducing the information signal. ing.
[0018]
In order to reduce the size of the optical pickup device, improve the performance, and improve the productivity, a semiconductor laser that emits a laser beam, a hologram element that diffracts return light from an optical disc, and a hologram are provided on the back side of the optical base 11. There is provided a hologram device in which a photodetector for detecting return light diffracted by the element is integrally integrated.
[0019]
Next, FIG. 2 is a sectional view showing an optical pickup device provided with a tilt adjusting mechanism of another example in the conventional example.
[0020]
As shown in FIG. 2, in a conventional optical pickup device 60 having a tilt adjusting mechanism of another example, a semiconductor laser 62 for emitting laser light into a frame inside 61a of an optical base 61 serving as a base, a semiconductor laser 62, There is provided a rising mirror 63 that reflects the laser beam from 62 and raises the laser light toward the optical disk D via an objective lens 65 described later.
[0021]
A concave spherical portion 61c is formed at a position protruding upward from the upper surface 61b of the optical base 61 with a radius R around the center point LO of the objective lens 65, and is formed at the center of the concave spherical portion 61c. A through-hole 61c1 for passing the laser light from the semiconductor laser 62 is formed.
[0022]
On the other hand, above the upper surface 61b of the optical base 61, a movable portion frame 64 formed in a frame shape using a resin material is arranged. On the upper surface 64a of the movable frame 64, there are a total of four suspension wires (only two upper and lower suspension wires are shown) in which the objective lens 65 is mounted in the objective lens mounting stepped hole 66a. It is swingably supported by a suspension 68 via a 67.
[0023]
Further, below the objective lens 65 in the movable portion frame 64, a convex spherical portion 64c formed to project downward from the lower surface 64b is formed with a substantially radius R about the center point LO of the objective lens 65, In addition, a through hole 64c1 for allowing the laser light from the semiconductor laser 62 to pass therethrough is formed in the center of the convex spherical portion 64c.
[0024]
The tilt mechanism is constituted by the concave spherical portion 61c formed on the optical base 61 and the convex spherical portion 64c formed on the movable portion frame 64, and the movable portion frame 64 is placed on the concave spherical portion 61c of the optical base 61. Of the movable lens frame 64 so that the optical axis K of the objective lens 65 takes an attitude substantially perpendicular to the signal surface of the optical disc D. After tilting the tilt angle of the movable portion frame 64 by three-dimensionally displacing the movable portion 64c on the concave spherical portion 61c of the optical base 61 in the tilt direction, the upper surface 61b of the optical base 61 and the movable portion frame 64 are adjusted. An adhesive 69 is inserted between the lower surface 64b and the lower surface 64b, and the two 61 and 64 are adhered and fixed in a state where the tilt is adjusted.
[0025]
[Problems to be solved by the invention]
By the way, in the optical pickup device 10A having an example of the tilt adjusting mechanism in the conventional example shown in FIG. 1, as described above, the yoke base 12 is provided with the tilt adjusting screw (not shown) provided on the back side of the optical base 11. The rear surface is pushed up against the urging force of the tilt adjusting leaf spring 26 abutting on the flat surface 12a of the yoke base 12, so that the optical axis K of the objective lens 13 attached to the lens holder 14 is not shown in the optical disk. The tilt adjustment screw and the yoke base 12 / suspension 16 (not shown) are fixed using an adhesive or the like after the tilt adjustment is performed so as to take a posture substantially perpendicular to the signal surface. The tilt adjusting mechanism including the tilt adjusting screw and the tilt adjusting leaf spring 26 shown in the drawing is complicated and problematic.
[0026]
On the other hand, in the optical pickup device 60 having a tilt adjusting mechanism of another example of the conventional example shown in FIG. 2, the movable portion frame 64 is formed on the concave spherical portion 61c formed on the optical base 61 as described above. The movable spherical body 64 is tilted so that the optical axis K of the objective lens 65 takes an attitude substantially perpendicular to the signal surface of the optical disk D by slidably fitting the convex spherical portion 64c. After the adjustment, the adhesive 69 is inserted between the upper surface 61b of the optical base 61 and the lower surface 64b of the movable portion frame 64, and the two 61 and 64 are bonded and fixed in a tilt-adjusted state. Since the adhesive 69 is applied in the tilting direction (vertical direction), the shrinkage due to the temporal change of the adhesive 69 and the stress change due to the shrinkage due to the temperature change of the adhesive 69 are caused in the tilt direction. To generate the vertical direction), problems such as deviated tilt angle of the objective lens 65 after the tilt adjustment is occurring.
[0027]
Therefore, an optical pickup device with a simple structure that can reliably adjust the tilt of the objective lens with respect to the signal surface of the optical disk is desired.
[0028]
[Means for Solving the Problems]
The present invention has been made in view of the above problems, and a first invention is to support a lens holder to which an objective lens is attached at each one end of four suspension wires, and The other end is swingably supported by a suspension provided on a base, and the tilt angle of the lens holder is tilted so that the optical axis of the objective lens is substantially perpendicular to the signal surface of the optical disk. In an optical pickup device configured to be adjustable,
The other ends of the four suspension wires are supported in advance on the left and right sides of the suspension, and the one end of each of the four suspension wires is connected to the signal surface of the optical disc by the optical axis of the objective lens. The four terminals protruding up and down on the left and right side surfaces of the lens holder so as to take a substantially vertical posture are soldered or joined by a conductive paste or an adhesive at the end surfaces of the respective terminals. Optical pickup device.
[0029]
According to a second aspect of the present invention, a lens holder to which an objective lens is attached is swingably supported in a movable portion frame via a plurality of suspension wires, and is provided below the objective lens in the movable portion frame. The formed convex spherical portion is slidably fitted on the concave spherical portion formed on the optical base, and the movable lens is positioned such that the optical axis of the objective lens takes a posture substantially perpendicular to the signal surface of the optical disk. The tilt angle of the movable frame is adjusted by displacing the convex spherical portion of the frame on the concave spherical surface of the optical base, and then the outer surface of the movable frame is placed on the optical base. In an optical pickup device fixed using an adhesive,
The upper portion of the outer surface of the movable portion frame body whose tilt angle has been adjusted by tilting the upper portion of the fixed wall provided on the optical base in the direction substantially parallel to the signal surface of the optical disk using the adhesive. An optical pickup device characterized by being adhered.
[0030]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the optical pickup device according to the present invention will be described in detail in the order of <first embodiment> and <second embodiment> with reference to FIGS.
[0031]
<First embodiment>
FIG. 3 is a perspective view showing an optical pickup device according to a first embodiment of the present invention,
FIG. 4 is a perspective view showing a case where the lens holder to which the objective lens is attached is soldered to four suspension wires in a state where the lens holder is tilt-adjusted, in the optical pickup device according to the first embodiment of the present invention;
FIG. 5 shows the optical pickup device of the first embodiment according to the present invention, in which the tilt of the lens holder to which the objective lens is attached is adjusted when the four terminals and four suspension wires attached to the side surfaces of the lens holder are used. It is the side view which showed typically for explaining a positional relationship, (a) has shown the state where a lens holder cannot rotate, (b), (c) has shown the state where a lens holder can rotate. FIG.
[0032]
The optical pickup device 10B of the first embodiment according to the present invention shown in FIGS. 3 and 4 is the same as the optical pickup device 10A of the conventional example described above with reference to FIG. Here, for convenience of explanation, the same reference numerals are given to the above-described constituent members, and the above-described constituent members are appropriately described as needed. , A description will be given focusing on the points different from the conventional one.
[0033]
As shown in FIGS. 3 and 4, in the optical pickup device 10B of the first embodiment according to the present invention, like the optical pickup device 10A of the conventional example described above with reference to FIG. Although the lens holder 14 on which the objective lens 13 is mounted is swung in the focus direction FO and the tracking direction TR with respect to the optical disk (not shown) via a plurality of (four) suspension wires 15, Explaining the points different from the example of the optical pickup device 10A in the conventional example, the leaf spring support 11d is not formed on the upper surface 11a of the optical base 11, and the tilt fixed on the leaf spring support 11d with this. The adjusting leaf spring 26 is not provided.
[0034]
Further, the suspension 16 is not fixed to the first yoke portion 12c cut and raised behind the yoke base 12 using the screw 20, and instead of the suspension 16, a suspension portion 11e is provided behind the upper surface 11a of the optical base 11. It is integrally formed in the shape of a character frame, whereby the dimensional accuracy of the suspension portion 11e formed on the optical base 11 can be ensured.
[0035]
In the first embodiment, a suspension 16 separate from the optical base 11 is fixed to the first yoke portion 12c of the yoke base 12 using a screw 20, similarly to the conventional example described with reference to FIG. It is applicable even if it is done.
[0036]
The lens holder 14 for mounting the objective lens 13 is formed by molding using a resin material having heat resistance and insulation properties for soldering. This lens holder 14 does not have the four protrusions 14c and the four conductive pins 21 provided on the upper and lower sides of the left and right sides as described in the conventional example. In addition, four terminals 14 d are provided so as to protrude from the left and right side surfaces integrally with the lens holder 14 in accordance with the approximate center position of the objective lens 13. The end of the focus coil 18 and the end of the tracking coil 19 are previously entangled with one of the four terminals 14d protruding up and down on the left and right side surfaces of the lens holder 14.
[0037]
Here, in the first embodiment, when the lens holder 14 to which the objective lens 13 is attached is swingably supported on the suspension portion 11e formed on the optical base 11 via four suspension wires 15, Damping material in which the suspension wires 15 are arranged substantially in parallel with the signal surface of an optical disk (not shown) and the other ends of the four suspension wires 15 are filled in the upper and lower sides of the left and right side surfaces of the suspension portion 11e, respectively. In the state of being fixed by the adhesive 28 and the adhesive 29, the tip portions of the other ends are soldered to the wiring board 22 which is fixed to the rear surface of the suspension portion 11e with an adhesive.
[0038]
Thereafter, the tilt angle of the lens holder 14 is adjusted in advance as described later, and then one end of each of the four suspension wires 15 is connected to the four terminals 14 d which are projected vertically on the left and right side surfaces of the lens holder 14. When soldering together with the end of the focus coil 18 and the end of the tracking coil 19 which have been entangled in advance, four ends of each of the four suspension wires 15 are projected upward and downward on the left and right side surfaces of the lens holder 14. The terminal 14d is characterized in that it is soldered at the end face of the end of the terminal 14d or joined using a conductive paste. Thus, the focus coil 18 and the tracking coil 19 are electrically connected to one of the four suspension wires 15.
[0039]
At this time, before soldering at one end of each of the four suspension wires 15 at four terminals 14 d protruding up and down on the left and right side surfaces of the lens holder 14, FIGS. 5A to 5C show. As described above, the lens holder 14 is rotated about the center point LHO of the lens holder 14 so that the optical axis K of the objective lens 13 attached to the lens holder 14 takes a posture substantially perpendicular to the signal surface of the optical disk (not shown). Need to be moved.
[0040]
More specifically, the state shown in FIG. 5A shows a state where the lens holder 14 to which the objective lens 13 is attached cannot rotate in the tilt direction. That is, when the lens holder 14 to which the objective lens 13 is attached is tilted in the tilt direction (up-down direction) about the center point LHO of the lens holder 14, one end of each of the four suspension wires 15 is connected to the lens holder 14. Of the four terminals 14d projecting up and down on the right and left side surfaces of the optical disk, the four suspension wires 15 are substantially parallel to the signal surface of the optical disk (not shown). Are supported in advance by the suspension portion 11e of the optical base 11 so that one end of each of the four suspension wires 15 is connected to the terminal 14d when the lens holder 14 rotates in the tilt direction (vertical direction). Is pushed up (or pushed down) by the part extended by the Soldering it would stay away from the site which extends out of the d becomes difficult.
[0041]
Therefore, in the first embodiment, as shown in FIGS. 5B and 5C, the lens holder 14 to which the objective lens 13 is attached is in a state where it can be rotated in the tilt direction. That is, at the distal ends of the four terminals 14d projecting up and down on the left and right side surfaces of the lens holder 14, an arc-shaped end surface 14d1 having a radius r around the center point LHO of the lens holder 14 is formed by molding. ing. If one end of each of the four suspension wires 15 is arranged outside the arc-shaped end surface 14d1 of each of the four terminals 14d, each one end of each of the four suspension wires 15 becomes four terminals 14d. Since the lens holder 14 can be rotated in the tilt direction about the center point LHO without contact, the optical axis K of the objective lens 13 attached to the lens holder 14 as shown in FIG. When the optical disk is tilted by θ with respect to the optical disk shown in the figure, the lens holder is set so that the optical axis K of the objective lens 13 takes a substantially perpendicular attitude to the optical disk (not shown) as shown in FIG. After tilt adjustment of the inclination angle of the fourteen, the one ends of the four suspension wires 15 can be soldered at the respective arc-shaped end surfaces 14d1 of the four terminals 14d.
[0042]
Note that one end of each of the four suspension wires 15 may be joined using a conductive paste at each of the arc-shaped end surfaces 14d1 of the four terminals 14d.
[0043]
Therefore, according to the optical pickup device 10B of the first embodiment, it is not necessary to provide a special tilt adjustment mechanism on the optical base 11, so that the optical pickup device 10B can be provided at low cost.
[0044]
In the above-described first embodiment, the lens holder 14 is formed using a resin material having heat resistance to soldering, and the four terminals 14 d protruding up and down on the left and right side surfaces of the lens holder 14. And the ends of the focus coil 18 and the tracking coil 19 are previously entangled with any of the four terminals 14d, so that one end of each of the four suspension wires 15 is connected to the four terminals 14d. In the above description, the electrical connection is made at the arcuate end face 14d1 of the lens. However, the present invention is not limited to this. If the lens holder 14 is formed of a resin material having no heat resistance, the four terminals 14d are integrated. Instead of this, four conductive terminals (not shown) are press-fitted vertically above and below the left and right side surfaces of the lens holder 14 so as to protrude. When formed and arranged in the same manner as described above, four suspension wires 15 can be electrically connected to the arcuate end faces of the four conductive terminals in a state where the lens holder 14 is tilt-adjusted, and the four conductive wires are connected. The end of the focus coil 18 and the end of the tracking coil 19 can also be electrically connected to the sex terminal.
[0045]
Furthermore, in the above-described first embodiment, one end of each of the four suspension wires 15 is attached to the focus coil 18 at the arc-shaped end face 14d1 of the four terminals 14d in a state where the lens holder 14 is tilt-adjusted. And the ends of the tracking coil 19 are soldered together or electrically connected using a conductive paste. However, the present invention is not limited to this. In the case where four terminals other than the above are additionally provided above and below the left and right side surfaces of the lens holder 14, one end of each of the four suspension wires 15 is connected with the lens holder 14 being tilt-adjusted. The four terminals 14d are joined at the tip end arc-shaped end surfaces 14d1 of the four terminals 14d using an adhesive, and the four suspension wires are connected. The tip of each end of the 15 to another four terminals with the focus coil 18 and tracking coil 19 may be soldered.
[0046]
<Second embodiment>
FIG. 6 is a perspective view showing an optical pickup device of a second embodiment according to the present invention,
FIG. 7 shows an optical pickup device according to a second embodiment of the present invention, in which a lens holder having an objective lens mounted thereon is swingably supported in a movable unit frame via four suspension wires. After adjusting the tilt, a perspective view showing a state where the movable portion frame body is bonded on the optical base using an adhesive,
FIG. 8 is a cross-sectional view for explaining a tilt adjusting mechanism formed on the optical base and the movable frame in the optical pickup device according to the second embodiment of the present invention.
[0047]
The optical pickup device 10C of the second embodiment according to the present invention shown in FIGS. 6 and 7 is the same as the optical pickup device 10A of the conventional example described above with reference to FIG. This is configured by combining with the optical pickup device 60 of another example in the conventional example described above. Here, for convenience of explanation, the same reference numerals are given to the components described above, and The constituent members described above will be appropriately described as needed, and constituent members different from the conventional ones will be assigned new reference numerals, and the description will focus on the points different from the conventional ones.
[0048]
In the optical pickup device 10C of the second embodiment according to the present invention shown in FIGS. 6 and 7, the optical pickup device 10A of the conventional example described above with reference to FIG. The technical idea of another example of the optical pickup device 60 in the conventional example described above is applied.
[0049]
In the second embodiment, the movable portion frame 41 disposed above the upper surface 11a of the optical base 11 is formed in a frame shape using a resin material, and the upper surface 41a of the movable portion frame 41 is opened, and A suspension portion 41b is formed integrally with the rear portion.
[0050]
The lens holder 14 to which the objective lens 13 is attached is supported by the suspension portion 41b via a plurality of (four) suspension wires 15 in the movable portion frame 41, and the objective lens attached to the lens holder 14 Numeral 13 is swingable with respect to an optical disc (not shown) in a focus direction FO and a tracking direction TR.
[0051]
The difference from the example of the optical pickup device 10A of the conventional example described above with reference to FIG. 1 with the application of the movable frame 41 in the second embodiment will be described. The yoke base 12 is not provided on the movable member 41. Instead of this, a pair of yoke members 43, 43 bent in a U-shape are provided on the front portion of the movable frame 41 and the rear suspension portion 41b from the lower surface 41e side to the upper surface 41a side. Is fixed by press-fitting or the like. Then, the pair of yoke members 43, 43 are bent in a U-shape, and a pair of magnets 17, 17 are fixed to each one piece, and each other piece opposing each one piece is placed in the lens holder 14. It penetrates before and after the object lens 13 and enters into a pair of substantially rectangular through holes 14a and 14b. Further, a separate suspension 16 is not provided above the yoke base 12, and a suspension portion 41 b is integrally formed in the movable frame 41 instead of the suspension 16.
[0052]
One end of each of the four suspension wires 15 is supported by each of four protrusions 14c formed so as to protrude up and down on the left and right side surfaces of the lens holder 14, and the tip of each one end is connected to the left and right sides of the lens holder 14. The four conductive pins 21 press-fitted on the upper and lower sides are soldered together with the end of the focus coil 18 or the end of the tracking coil 19, and the other end opposite to the one end is suspended. A wiring in which the upper and lower sides of the right and left side surfaces of the portion 41b are fixedly supported by a damping material 44 and an adhesive 45, respectively, and the other end portion is fixed to the rear surface of the suspension portion 41b with an adhesive. Each is soldered to the substrate 22.
[0053]
In the second embodiment, as in the conventional example described above with reference to FIG. 1, when the lens holder 14 is formed using a resin material having heat resistance to soldering, the lens holder The four conductive pins 21 are not pressed into the upper and lower sides of the left and right sides of the lens holder 14, and instead of the four conductive pins 21, four terminals are integrally formed with the lens holder 14 on the upper and lower sides of the left and right sides of the lens holder 14. (Not shown), the terminal of the focus coil 18 or the end of the tracking coil 19 is previously entangled with each terminal, and then the suspension wire together with the end of the focus coil 18 or the end of the tracking coil 19 is provided. There is also a method of soldering each of the 15 ends.
[0054]
8, a concave spherical portion 11h is formed on the upper surface 11a of the optical base 11 with a radius R about the center point LO of the objective lens 13, and the concave spherical portion 11h A through-hole 11h1 for passing a laser beam is formed in the center of the hole.
[0055]
Further, below the objective lens 13 in the movable frame 41, a convex spherical portion 41f projecting downward from the lower surface 41e is formed with a substantially radius R about the center point LO of the objective lens 13, In addition, a through hole 41f1 for allowing laser light to pass therethrough is formed in the center of the convex spherical portion 41f.
[0056]
A tilt mechanism is configured by the concave spherical portion 11h formed on the optical base 11 and the convex spherical portion 41f formed on the movable portion frame 41, and the movable portion frame 41 is placed on the concave spherical portion 11h of the optical base 11. Of the movable lens frame 41 so that the optical axis K of the objective lens 13 takes a substantially perpendicular attitude with respect to the signal surface of the optical disc (not shown). After the spherical portion 41f is three-dimensionally displaced in the tilt direction on the concave spherical portion 11h of the optical base 11, the tilt angle of the movable portion frame 41 is adjusted, and then the tilt angle of the movable portion frame 41 is adjusted. The upper portions of the left and right outer surfaces 41c and 41d are adhered and fixed to the respective upper portions of the fixed walls 11f and 11g vertically suspended on the upper surface 11a of the optical base 11 using an adhesive 42. At this time, the upper portions of the fixed walls 11f and 11g formed on the optical base 11 are formed on the outer surfaces 41c and 41d so that the upper portions of the left and right outer surfaces 41c and 41d of the movable frame 41 are easily bonded. The corner is recessed one step as shown.
[0057]
Accordingly, the adhesive 42 fills the space above the left and right outer surfaces 41c and 41d of the movable frame 41 and the space above the fixed walls 11f and 11g vertically suspended on the upper surface 11a of the optical base 11. Accordingly, the bonding direction of the bonding material 42 is substantially parallel to the signal surface of the optical disk (not shown). In other words, the bonding material 42 is bonded in a direction substantially perpendicular to the tilt direction (vertical direction). Unlike the case of the optical pickup device 60 of another example in the conventional example shown in FIG. 2, the shrinkage due to the temporal change of the adhesive 42 and the stress change due to the shrinkage due to the temperature change of the adhesive 42 are caused in the tilt direction (vertical direction). ), The problem of the tilt angle of the objective lens 13 being shifted after the tilt adjustment does not occur at all, so that the quality of the optical pickup device 10C is improved and the reliability is improved. It can contribute to.
[0058]
Thereafter, a decorative cover 46 (FIG. 6) molded using a resin material is fitted over the lens holder 14.
[0059]
In the first and second embodiments, the case where the moving coil system (MC system) is applied by fixing the focus coil 18 and the tracking coil 19 to the swingable lens holder 14 has been described. Although not shown in the drawings, a moving magnet system (MM system) in which a focus coil and a tracking coil are fixed to the optical base 11 serving as a fixed part and a magnet is fixed to a lens holder side serving as a movable part is used. ) Can be applied to the tilt adjustment which is a main part of the present invention.
[0060]
【The invention's effect】
In the optical pickup device according to the present invention, the lens holder to which the objective lens is attached is supported by one end of each of the four suspension wires, and the four suspension wires are provided. The other end of the lens is swingably supported on a suspension provided on the base, and the tilt angle of the lens holder is adjusted so that the optical axis of the objective lens is substantially perpendicular to the signal surface of the optical disk. In doing so, the other ends of the four suspension wires are supported in advance on the left and right sides of the suspension, and the one end of each of the four suspension wires is connected with the optical axis of the objective lens with respect to the signal surface of the optical disk. Soldering at the end surfaces of the tips of the four terminals protruding up and down on the left and right sides of the lens holder so as to take a substantially vertical posture. Since joined by only or a conductive paste or adhesive, there is no need to provide a special tilt adjustment mechanism on Opti Cal base can provide an optical pickup apparatus inexpensively.
[0061]
According to the second aspect of the present invention, in particular, the lens holder to which the objective lens is attached is swingably supported in the movable portion frame through a plurality of suspension wires, and is provided below the objective lens in the movable portion frame. The convex spherical part formed on the optical base is slidably fitted on the concave spherical part formed on the optical base, and the movable part is set so that the optical axis of the objective lens takes a position substantially perpendicular to the signal surface of the optical disk. The tilt angle of the movable part frame is adjusted by displacing the convex spherical part of the frame on the concave spherical part of the optical base, and then the outer surface of the movable part frame is bonded to the optical base with an adhesive. To fix the optical disk, the upper part of the outer surface of the movable part frame whose tilt angle has been adjusted by tilting the upper part of the fixed wall provided on the optical base to the part substantially parallel to the signal surface of the optical disk using an adhesive. Since the adhesive adheres to the lens, no shrinkage due to the temporal change of the adhesive or a change in stress due to the shrinkage due to the temperature change of the adhesive occurs in the tilt direction (up-down direction), so that the tilt angle of the objective lens is shifted after the tilt adjustment. The problem described above does not occur at all, and it is possible to contribute to improvement in quality and reliability of the optical pickup device.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an optical pickup device provided with an example of a tilt adjustment mechanism in a conventional example.
FIG. 2 is a cross-sectional view showing an optical pickup device including a tilt adjusting mechanism of another example in a conventional example.
FIG. 3 is a perspective view showing an optical pickup device of a first embodiment according to the present invention.
FIG. 4 is a perspective view showing a case where the lens holder to which the objective lens is attached is soldered to four suspension wires in a state where the tilt is adjusted in the optical pickup device according to the first embodiment of the present invention.
FIG. 5 is a perspective view of the optical pickup device according to the first embodiment of the present invention, in which when adjusting the tilt of the lens holder to which the objective lens is attached, four terminals and four suspension wires attached to the side surfaces of the lens holder; FIGS. 3A and 3B are side views schematically illustrating a positional relationship of FIGS. 3A and 3B, wherein FIG. 3A illustrates a state in which the lens holder cannot rotate, and FIGS. FIG.
FIG. 6 is a perspective view showing an optical pickup device according to a second embodiment of the present invention.
FIG. 7 is a perspective view of an optical pickup device according to a second embodiment of the present invention, in which a lens holder to which an objective lens is attached is swingably supported in a movable unit frame via four suspension wires. FIG. 9 is a perspective view showing a state in which the movable frame is adhered to the optical base using an adhesive after tilt adjustment of the body.
FIG. 8 is a cross-sectional view illustrating a tilt adjustment mechanism formed on an optical base and a movable frame in the optical pickup device according to a second embodiment of the present invention.
[Explanation of symbols]
10B ... the optical pickup device of the first embodiment,
10C: Optical pickup device of second embodiment,
11 optical base, 11a upper surface, 11e suspension part,
11f, 11g: fixed wall, 11h: concave spherical part,
13: objective lens, 13a: ring-shaped edge,
14 ... Lens holder, 14d ... Terminal, 14d1 ... Arc end face
14e: Stepped hole for mounting an objective lens,
15 ... Suspension wire,
41: movable frame, 41a: upper surface, 41c, 41d: left and right outer surfaces,
41f: convex spherical part,
42 ... adhesive,
K: optical axis of objective lens,
LHO: the center point of the lens holder,
LO: The center point of the objective lesbian.

Claims (2)

A lens holder to which an objective lens is attached is supported by each one end of four suspension wires, and the other end of each of the four suspension wires is swingably supported by a suspension provided on a base. In an optical pickup device configured such that the tilt angle of the lens holder can be adjusted so that the optical axis of the objective lens takes a posture substantially perpendicular to the signal surface of the optical disc,
The other ends of the four suspension wires are supported in advance on the left and right sides of the suspension, and the one end of each of the four suspension wires is connected to the signal surface of the optical disc by the optical axis of the objective lens. The four terminals protruding up and down on the left and right side surfaces of the lens holder so as to take a substantially vertical posture are soldered or joined by a conductive paste or an adhesive at the end surfaces of the respective terminals. Optical pickup device. A lens holder to which an objective lens is attached is swingably supported in a movable frame by a plurality of suspension wires, and a convex spherical portion formed below the objective lens in the movable frame is optically mounted. The convex spherical portion of the movable portion frame is fitted slidably on the concave spherical portion formed on the base so that the optical axis of the objective lens takes a posture substantially perpendicular to the signal surface of the optical disk. Was displaced on the concave spherical portion of the optical base to adjust the tilt angle of the movable portion frame, and then the outer surface of the movable portion frame was fixed on the optical base using an adhesive. In an optical pickup device,
The upper portion of the outer surface of the movable portion frame body whose tilt angle has been adjusted by tilting the upper portion of the fixed wall provided on the optical base in the direction substantially parallel to the signal surface of the optical disk using the adhesive. An optical pickup device characterized by being adhered.

Images