JP3637696B2 - Adjustment method of optical pickup - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method of adjusting an optical video disc, a compact disc, an optical pickup for adjusting an optical axis of an optical pickup used for reading and writing of data of the optical recording medium such as a magneto-optical disk.
[0002]
[Prior art]
A conventional optical pickup actuator will be described below with reference to FIGS. FIG. 17 is a plan view of a conventional optical pickup, and FIG. 18 is a cross-sectional view taken along line CC and DD of the optical pickup in FIG.
[0003]
In FIG. 17 and FIG. 18, reference numeral 1 denotes an objective lens holding cylinder, and an objective lens 4 for condensing the laser 3 is fixed to the disk 2 on which information is recorded by means such as adhesion. Further, a focus coil 5 and a tracking coil 6 for operating in the focus direction and the tracking direction are fixed to the objective lens holding cylinder 1 by means such as adhesion. 7a and 7b are permanent magnets constituting a magnetic circuit for driving the objective lens holding cylinder 1 in the focus direction and the tracking direction, and the N pole is magnetized on the objective lens 4 side and the S pole is magnetized on the opposite side. . The disk 2 on which information is recorded is rotated by a spindle motor or the like (not shown). Reference numeral 8 denotes a conductive linear elastic member that holds the objective lens holding cylinder 1 in a neutral position, and supplies power to the focus coil 5 and the tracking coil 6. The permanent magnets 7a and 7b are non-magnetic elastic members so that a magnetic attractive force is not exerted by them. A spring substrate 9 is attached to both sides of the objective lens holding cylinder 1 by means such as adhesion, and is a relay substrate for supplying power from the linear elastic member 8 to the focus coil 5 and the tracking coil 6. Yes, one end is connected by soldering or the like so that each line conducts to each linear elastic member 8. Reference numeral 10 denotes a suspension holder in which a power supply (not shown) for supplying power to one end is fixed by means such as adhesion, and is a linear elastic member 8 and is fixed by soldering on the side opposite to the spring substrate 9. is there.
[0004]
The suspension holder 10 is fixed to a skew adjustment member 170 that serves as a skew adjustment of the objective lens and serves as a yoke for the permanent magnet. The skew adjustment member 170 is provided with a spherical surface centered on the objective lens 4 on the lower surface of the objective lens 4, and a part of the carriage 11 that can move from the inner circumference to the outer circumference of the disc board 2 is provided with an adhesive 18 or the like. The other two places are temporarily fixed by means such as screws 19 or the like. By tightening or loosening these two screws 19 separately, the skew can be adjusted around the objective lens 4 at the spherical surface where the carriage 11 and the skew adjusting member 170 are in contact with each other. Reference numeral 12 denotes a low clay such as silicon gel as a damping member in order to suppress the Q value of the primary resonance of the linear elastic member 8 generated in the system including the actuator including the objective lens holding cylinder 1 and the linear elastic member 8. It is a material.
[0005]
The operation of the optical pickup actuator configured as described above will be described. First, a current is supplied from an unillustrated power source to the FPC, and current is supplied to the focus coil 5 and the tracking coil 6 through the linear elastic member 8 and the spring substrate 9. By passing a current through the focus coil 5 and the tracking coil 6, the magnetic force generated from the permanent magnet 7 is received, and the focus coil 5 and the tracking coil 6 act according to Fleming's left hand rule, respectively. The actuator is driven. The objective lens 4 is controlled so that it is always focused on and follows the disk 2 by the direction and magnitude of the current flowing through the coils 5 and 6. Next, when the current supply is stopped, the spring force of the linear elastic member 8 always returns to the neutral position with respect to the focus direction and the tracking direction. Reference numeral 13 denotes an optical unit having a light emitting element and a light receiving element for the laser light 3, and the laser light 3 emitted from the optical unit 13 passes through an optical component 13a constituting a hologram and is a raised mirror 14 coated with a multilayer film. The light is completely reflected by the surface of the light and condensed by the objective lens 4, and an optical spot is formed on the disk 2. On the contrary, the laser beam 3 reflected from the disk board 2 is reflected by the rising mirror 14, passes through the optical component 13a constituting the hologram, and is condensed on a light receiving element (not shown). Based on the optical information collected on the light receiving element, the objective lens 4 is controlled so as to always focus on and follow the disk 2.
[0006]
Next, the contact when the optical pickup actuator as described above is displaced will be described.
[0007]
First, when the optical pickup actuator is displaced in the tracking direction, the objective lens holding cylinder 1 and the skew adjusting member 170 come into contact with each other. Since the center of gravity of the optical pickup actuator is designed in the coil portion G so as to coincide with the drive center, a rotational moment having a rotational radius r is generated. Therefore, when the carriage 11 is sought at a high speed due to high speed access, the optical pickup actuator is displaced with respect to the carriage 11 by the inertial force, and a rotational moment is generated in the optical pickup actuator for mechanical contact. Since out of focus control or the like occurs, it is necessary to seek the carriage 11 at a speed that does not cause mechanical contact.
[0008]
[Problems to be solved by the invention]
However, in the above-described conventional optical pickup actuator, the disk board 2, the actuator movable portion, the skew adjustment mechanism 170, and the carriage 11 are configured in the thickness direction, and it is difficult to further reduce the thickness.
[0009]
The present invention has been made to solve the above problems, there is provided a method of adjusting an optical pickup to improve the mass productivity with thinning can be easily.
[0010]
[Means for Solving the Problems]
Adjusting method of an optical pickup of the present invention to achieve this object, a skew adjusting mechanism for performing a skew adjustment of the optical pickup and the optical pickup is formed as a separate body fixedly supports the skew adjustment mechanism in the optical pickup Since the fixing means is detached from the optical pickup after the skew adjustment is performed, the optical pickup is rich in mass productivity and can be reduced in cost, thickness, weight and size by reducing the number of parts.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
According to a first aspect of the present invention, there is provided an objective lens for condensing and projecting laser light onto a recording surface of an optical recording medium, and an objective that can be moved in a focusing direction and a tracking direction with respect to the optical recording medium by bonding the objective lens. An adjustment method of an optical pickup comprising a lens holding cylinder and an actuator having a focus coil and a tracking coil for driving the objective lens holding cylinder in two directions, and adjusting an optical axis of the objective lens with respect to the optical recording medium The skew adjustment mechanism is formed separately from the optical pickup, and the skew adjustment mechanism includes a fixing unit that fixes and supports the optical pickup, and the skew adjustment mechanism is mounted on the objective lens while the optical pickup is fixed and supported by the fixing unit. Adjust the optical axis, and after adjusting the optical axis, release the fixed support of the optical pickup by the fixing means and Is intended to disengage said locking means from Kkuappu, will be able of separating and separated from the optical pickup skew adjustment mechanism to be unnecessary after skew adjustment, the optical pickup itself can be made thinner, lighter and compact.
[0012]
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a plan view of an optical pickup according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line AA and BB of the optical pickup shown in FIG. In FIGS. 1 and 2, reference numeral 1 denotes an objective lens holding cylinder, and an objective lens 4 for condensing a laser 3 is fixed to a disk board 2 on which information is recorded by means such as adhesion. Further, a focus coil 5 and a tracking coil 6 for operating in the focus direction and the tracking direction are fixed to the objective lens holding cylinder 1 by means such as adhesion. 7a and 7b are permanent magnets constituting a magnetic circuit for driving the objective lens holding cylinder 1 in the focus direction and the tracking direction, and the N pole is magnetized on the objective lens 4 side and the S pole is magnetized on the opposite side. . The disk 2 on which information is recorded is rotated by a spindle motor or the like (not shown). Reference numeral 8 denotes a conductive linear elastic member that holds the objective lens holding cylinder 1 in a neutral position, and supplies power to the focus coil 5 and the tracking coil 6. The permanent magnets 7a and 7b are non-magnetic elastic members so that a magnetic attractive force is not exerted by them. A spring substrate 9 is attached to both sides of the objective lens holding cylinder 1 by means such as adhesion, and is a relay substrate for supplying power from the linear elastic member 8 to the focus coil 5 and the tracking coil 6. Yes, one end is connected by soldering or the like so that each line conducts to each linear elastic member 8. Reference numeral 10 denotes a suspension holder in which an FPC (not shown) for supplying power to one end is fixed by means such as adhesion, and is a linear elastic member 8 and is fixed to the side opposite to the spring substrate 9 by soldering. It is. The suspension holder 10 has adjustment mounting holes 10a and 10b, and is used for skew adjustment of the objective lens 4 by an optical adjustment mechanism 17 described later. The suspension holder 10 is fixed to a carriage 11 that can move from the inner periphery to the outer periphery of the disc board 2 by means of adhesion or the like in order to read information recorded from the inner circumference to the outer circumference of the disc board 2. Reference numeral 12 denotes a damping member such as silicon gel in order to suppress the primary resonance Q value of the linear elastic member 8 generated in the system constituted by the actuator movable portion including the objective lens holding cylinder 1 and the linear elastic member 8. It is a low clay material.
[0013]
3 is a cross-sectional view in the X-axis direction passing through the adjustment mounting holes 10a and 10b in FIG. 1, and FIG. 4 is a cross-sectional view in the Y-axis direction passing through the adjustment hole 10a in FIG. On both sides, the optical adjustment mechanism 17 is fixed to the lifting jig 16 and the lifting jig 16 for adjusting the lifting and lowering movement to be fixedly attached to the adjustment mounting holes 10a and 10b formed in the suspension holder 10 of the optical pickup. The angle φ with respect to the radial direction (X-axis direction in the coordinate axis) and the tangential direction (Y-axis direction in the coordinate axis) with respect to the track direction of the disc board 2 around the optical center O of the objective lens 4 of the optical pickup. a rotation jig 15 for adjusting θ, and is configured separately from the optical pickup.
[0014]
The elevating jig 16 includes an elevating board 16c to which adjustment jig pins 16a and 16b inserted into the adjusting attachment holes 10a and 10b of the suspension holder 10 are attached to the upper side surface, and a lower side surface side of the elevating board 16c. The fixed substrate 16d to be disposed, and the side surface of the fixed substrate 16d are pivotally supported. The substantially arcuate end surface is brought into contact with the lower surface of the lift substrate 16c so that the lift substrate 16c is rotated. And a cam 16e to be raised or lowered. The rotating jig 15 has an arc surface having a radius R1 in the radial direction (X-axis direction) around the optical center O of the objective lens 4 of the optical pickup when the optical adjustment mechanism 17 is mounted on the suspension holder 10 of the optical pickup. An X-axis fixed substrate 15b formed on the upper surface, an X-axis rotating substrate 15a that is in sliding contact with the arc surface of the X-axis fixed substrate 15b and slides (φ direction) on the arc surface, and the objective lens 4, the Y-axis fixed substrate 15 d formed by an upper surface having an arc surface of radius R2 in the tangential direction (Y-axis direction) with the optical center O at the center, and the lower surface is in sliding contact with the arc surface of the Y-axis fixed substrate 15 d. In addition, the upper surface is fixed to the X-axis fixed substrate 15b, and the Y-axis rotating substrate 15c is slid (θ direction) on the arc surface.
[0015]
Next, the assembly of the optical pickup and the skew adjustment operation of the objective lens will be described with reference to FIGS. 1 to 16 as an example of the type of optical pickup held by the four elastic members 8.
[0016]
5 is an X-axis direction sectional view showing a process of inserting the adjustment jig pins 16a and 16b, FIG. 6 is an X-axis direction sectional view showing a state where the adjustment jig pins 16a and 16b are inserted, and FIG. 6 is a cross-sectional view in the Y-axis direction of FIG.
[0017]
First, the movable part including the objective lens holding cylinder 1 and the suspension holder are assembled by soldering or the like via the elastic member 8, and the actuator part as shown in FIGS. 1 to 3 is assembled. On the other hand, the carriage 11 to which the raising mirror 14 and the optical unit 13 are attached and the above-described actuator unit are inserted into the carriage 11. Next, the optical adjustment operation will be described.
[0018]
First, in order to perform temporary positioning with respect to the carriage 11, the suspension holder 10 is held down to perform positioning. The suspension holder 10 in this positioned state is positioned above the optical adjustment mechanism 17 as shown in FIGS. In this state, the cam 16e is rotated in the direction of arrow A from the position shown in FIG. As shown in FIG. 5 (b), the adjustment jig pins 16 a and 16 b are inserted into the adjustment mounting holes 10 a and 10 b of the suspension holder 10 through the insertion holes 11 a and 11 b of the carriage 11 as the lift board 16 c is lifted. The FIG. 6 shows a cross-sectional state in the X-axis direction through which the adjustment jig pins 16a and 16b are inserted, and FIG. 7 shows a cross-sectional state in the Y-axis direction.
[0019]
FIG. 8 is an X-axis direction sectional view showing a process of fixing and integrating the suspension holder 10 and the optical adjustment mechanism 17, and FIGS. 9 and 10 are views showing a process of performing skew adjustment in the Y-axis direction. In FIG. 8, with the adjustment jig pins 16a and 16b inserted through the adjustment mounting holes 10a and 10b, the adjustment jig pin 16b is moved in the direction of arrow C as shown in FIG. The suspension holder 10 is held by the adjustment jig pins 16a and 16b, and the suspension holder 10 and the optical adjustment mechanism 17 are fixedly integrated. As shown in FIG. 9 or FIG. 10, the Y-axis rotating board 15c is moved in the θ direction based on a signal obtained from the optical unit 13 by performing each control of focus and tracking on the disk board 2 in this fixed and integrated state. The skew is adjusted in the Y-axis direction by rotating the objective lens 4 by a predetermined angle at which the best optical point is obtained with the radius R2 centered on the optical center O of the objective lens 4.
[0020]
11 and 12 are diagrams illustrating a process of performing skew adjustment in the X-axis direction.
When the skew adjustment in the Y-axis direction (tangential direction) is completed, X and X are controlled based on the signal obtained from the optical unit 13 by controlling each of the focus and tracking on the disk 2 in the same manner as the skew adjustment in the θ direction. As shown in FIG. 11 or FIG. 12, the shaft rotation board 15a is rotated by a predetermined angle at a radius R1 centered on the optical center O of the objective lens 4 to adjust the skew in the X-axis direction.
[0021]
FIG. 13 is a diagram illustrating an adhesive filling process, and FIG. 14 is a diagram illustrating a process of fixing and integrating. In FIG. 13, after the skew is adjusted by rotating it in the θ direction and the φ direction by a predetermined angle as described above, the adhesive 18 is filled in as shown in FIG. 13 in order to maintain this state. The adhesive 18 holds the relationship between the suspension holder 10 and the carriage 11 after skew adjustment, and after the adhesive 18 is cured, the adjustment jig pin 16b is moved in the direction of arrow D as shown in FIG. The fixed integration between the suspension holder 10 and the two adjustment jig pins 16a and 16b is released.
[0022]
15 is a cross-sectional view in the X-axis direction showing the process of pulling out the adjustment jig pins 16a and 16b, and FIG. 16 is a cross-sectional view in the Y-axis direction of FIG.
[0023]
The fixing jig pins 16a and 16b, which have been released from the fixed integration, rotate the cam 16e in the direction of arrow E as shown in FIG. 14, thereby moving the lifting board 16c into the arrow as shown in FIGS. It is lowered in the F direction and extracted from the insertion holes 11a and 11b of the carriage 11.
[0024]
The operation of the optical pickup actuator configured as described above will be described. First, a current is supplied from a power source (not shown) to the FPC, and current is supplied to the focus coil 5 and the tracking coil 6 through the linear elastic member 8 and the spring substrate 9. By passing a current through the focus coil 5 and the tracking coil 6, the magnetic force generated from the permanent magnets 7 a and 7 b is received, and the focus coil 5 and the tracking coil 6 act according to Fleming's left-hand rule, respectively. The actuator movable part including is driven. The objective lens 4 is controlled so that it is always focused on and follows the disk 2 by the direction and magnitude of the current flowing through the coils 5 and 6. Next, when the current supply is stopped, the spring force of the linear elastic member 8 always returns to the neutral position with respect to the focus direction and the tracking direction. Reference numeral 13 denotes an optical unit having a light emitting element and a light receiving element for the laser beam 3, and the laser beam 3 emitted from the optical unit 13 passes through an optical component 13a constituting a hologram and is a raised mirror 14 coated with a multilayer film. The light is completely reflected by the surface of the light and condensed by the objective lens 4, and an optical spot is formed on the disk 2. On the other hand, the laser beam 3 reflected from the disk board 2 is reflected by the rising mirror 14, passes through the optical component 13a constituting the hologram, and is focused on a light receiving element (not shown). Based on the optical information collected on the light receiving element, the objective lens 4 is controlled so as to always focus on and follow the disk 2.
[0025]
【The invention's effect】
As described above, according to the present invention, the skew adjustment mechanism for adjusting the skew of the optical pickup is formed separately from the optical pickup, and after the skew adjustment is performed by fixing and supporting the skew adjustment mechanism to the optical pickup, the optical pickup Since the skew adjustment mechanism is separated from the optical pickup, the optical pickup is highly mass-productive, and has the effect of reducing the number of parts, thereby reducing the cost, thickness, weight and size.
[Brief description of the drawings]
FIG. 1 is a plan view of an optical pickup according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along lines AA and BB of the optical pickup shown in FIG. Cross-sectional view in the X-axis direction passing through FIG. 4 Cross-sectional view in the Y-axis direction passing through the adjustment hole in FIG. 1 FIG. 5 Cross-sectional view in the X-axis direction showing the process of inserting the adjustment jig pin FIG. FIG. 7 is a cross-sectional view in the X-axis direction showing a state where the tool pin is inserted. FIG. 7 is a cross-sectional view in the Y-axis direction of FIG. 9 is a diagram illustrating a process of performing skew adjustment in the Y-axis direction. FIG. 10 is a diagram illustrating a process of performing skew adjustment in the Y-axis direction. FIG. 11 is a diagram illustrating a process of performing skew adjustment in the X-axis direction. 12 is a diagram showing a process of adjusting skew in the X-axis direction. FIG. 13 is an adhesive filling process. FIG. 14 is a diagram showing a process of fixing and integrating. FIG. 15 is a cross-sectional view in the X-axis direction showing a process of pulling out the adjusting jig pin. FIG. 16 is a cross-sectional view in the Y-axis direction of FIG. FIG. 18 is a plan view of the optical pickup of FIG. 17. FIG. 17 is a cross-sectional view of the optical pickup of FIG.
DESCRIPTION OF SYMBOLS 1 Objective lens holding | maintenance cylinder 4 Objective lens 10 Suspension holder 10a, 10b Adjustment attachment hole 11 Carriage 11a, 11b Insertion hole 13 Optical unit 15 Rotating jig | tool 15a, 15c Rotating board | substrate 15b, 15d Fixed board | substrate 16 Lifting jig | tool 16a, 16b Adjustment jig pin 16c Elevating board 16d Fixed board 16e Cam 17 Optical adjustment mechanism 18 Adhesive 20 Coil spring

Claims (1)

An objective lens for condensing and projecting laser light onto a recording surface of an optical recording medium, an objective lens holding cylinder that can be moved in a focusing direction and a tracking direction with respect to the optical recording medium by bonding the objective lens, and holding the objective lens a of the optical pickup adjusting method and an actuator having focusing coils and tracking coils for driving the cylinder in two directions, a skew adjusting mechanism for adjusting the optical axis of the objective lens relative to the optical recording medium and the optical pickup The skew adjustment mechanism includes a fixing unit that fixes and supports the optical pickup, and the skew adjustment mechanism adjusts the optical axis of the objective lens in a state where the optical pickup is fixed and supported by the fixing unit. the fixed from the optical pickup to release the support of the optical pickup according to the post-adjustment fixing means Adjustment method for an optical pickup, characterized in that disengaging the stage.

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