JP3089999B2 - Optical pickup device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pickup device for recording and reproducing information on an optical disk, a magneto-optical disk or the like.

[0002]

2. Description of the Related Art Generally, for example, in a pickup for an optical disk, a beam for reading or writing is
Since it is necessary to irradiate the optical disc surface in focus with the objective lens in focus and follow this beam in the track direction of the optical disc, the objective lens is orthogonal to the focus direction which is the optical axis direction and the focus direction. It is movably supported in the tracking direction.

As a method of supporting the objective lens in a movable state on the optical pickup main body, there are conventionally a spring type and a sliding type.
No. 104227 or Japanese Patent Application No.
Wire type (4W as proposed in -261144)
Equation) is known.

Here, the configuration of the optical pickup device proposed by the present applicant will be described with reference to FIGS.

In this optical pickup device, the inner surface of the center of the suspension base 4 is applied to the plate-shaped fixed base 1 and the outer side of the mounting plate 2 erected at the end thereof, and is fixed to the outside of the suspension base 4. The suspension base 4 and the fixing plate 3 are fixed to the mounting plate 2 with the washer 6 and screws 7 with the plate 3 applied thereto. Here, the fixing plate 3 and the mounting plate 2 constitute a fixing member 5.

The end of the suspension base 4 facing the fixing plate 3 is separated from the fixing plate 3 by a small distance except for the center, thereby forming a space 8. A space between both ends of the fixed plate 3 and the space 8 formed in the suspension base 4 is filled with a damper member 9 made of gel or rubber which is stable against temperature change, and both are joined at the ends. And enhance the damper effect.

Further, one end of a suspension wire 10 serving as a support member of two to four upper and lower members is fixed on the side surface of the fixing plate 3 by heating or the like by soldering or the like, and is extended in the horizontal direction in FIG. The movable member 11 made of resin is supported. Therefore, the movable member 11 has a flexible 4.
It is supported by the tip of the wire 10 so as to be movable with a slight force. In this case, the stretched state of the wire 10 is
When viewed from the upper surface with respect to, it is set in a C shape. Grooves 12 and 13 are formed in the suspension base 4 and the movable member 11 where the wire 10 is stretched, respectively, and the wire 10 is guided along the grooves 12 and 13.

The movable member 11 includes a lens holder 15 for holding the objective lens 14 and a holder plate 16 made of, for example, a printed circuit board, which is located near the center of the holder and to which the other end of the wire 10 is connected and fixed. Have. In this case, the position where the wire is fixed on the movable member 11 is set such that the object lens 1
4 is set at a position symmetrical to 4. Here, the virtual intersection point O refers to an intersection point on an extension of the plurality of (two to four) wires 10 stretched in a C shape, and is defined similarly in the following.

The objective lens 14 and the virtual intersection O
The lens holder 15 on a straight line perpendicular to the straight line passing through the center of the fixed plate 3 is provided with a pair of annular focus coils 17 whose interiors are hollow at positions symmetrical about the virtual intersection O, These focus coils 17
Are provided with a pair of tracking coils 18, respectively. A pair of yokes 19 are erected from the fixed base 1 outside the hollow portion of the focus coil 17 and outside thereof so as to sandwich the focus coil 17 and the tracking coil 18.
Is provided with a magnet 20.

Therefore, by controlling the current of the focus coil 17, the lens holder 15 moves in the focus direction (optical axis direction) indicated by the arrow shown in FIG. As a result, the optical disk D moves in the tracking direction indicated by the arrow in FIG.

When the track is moved (particularly during a track search, etc.), the movable member 11 supported by the fixed member 5 in a floating state by the wire 10 swings, but the focus coil 17 and the tracking coil 18 are moved by the yoke 19 and the yoke 19. By contacting the magnetic circuit including the magnet 20, the magnetic circuit functions as a stopper.

The virtual intersection O of the movable member 11
Opposite part 21 symmetrical with the objective lens 14 about the center
Functions as a damper block, and the above-described groove 13 is formed in the damper block portion 21 so as not to interfere with the portion where the wire 10 passes as described above. An auxiliary balancer 22 whose mass is adjusted is provided at the center of the damper block portion 21 so as to balance the left and right masses in FIG.

The entire fixing member 5 is moved in the longitudinal direction, that is, in the radial direction of the optical disk D by, for example, rotation of a rod-shaped screw screw 23.

In the device configured as described above, a structure for suppressing unnecessary resonance in a high frequency band is adopted as a mounting structure of the objective lens 14. As shown in FIG. 6, a mounting portion of the objective lens 14 with respect to the lens holder 11 is formed with a lens receiving recess 15 a having a through hole formed through a central portion thereof in a downward direction, and an upper end of the through hole. Is enlarged. At the bottom of the lens receiving recess 15a and around the upper end opening of the through hole, a not-shown prescribed boss having a projecting thickness set at a predetermined height is formed in a ring shape along the opening. Is formed.

In the optical pickup device configured as described above, when the optical pickup device is driven, the focus coil 1 is driven.
The lens holder 15 moves in the focus direction (optical axis direction) in accordance with the current flowing through the tracking coil 7 and the tracking coil 18.
In this case, the optical disk D is accessed by moving in the tracking direction. In such a case, by providing the damper block portion 21 having the balancer function and the auxiliary balancer 22, the right and left mass balance in FIG. Therefore, generation of unnecessary rotational force at the time of access can be significantly suppressed.

As a result, the dynamic balance not only in the focus direction, which is the optical axis direction, but also in the tracking direction in which the screw 23 moves in the direction of the arrow can be significantly improved, and the settling at the time of access can be improved.

The fixed plate 3 and the suspension base 4
By connecting the damper members 9 between both ends thereof, unnecessary resonance is removed and the damper effect at the time of driving the apparatus can be greatly improved.

[0018]

By the way, the optical pickup device having the above-mentioned structure has many advantages as described above, but it is necessary to adjust individual adjustments when assembling each element of the device or assembling it into each type of equipment. Consideration is somewhat lacking.

That is, the suspension base 4 and the fixing plate 3 are fixed to the mounting plate 2 with the washer 6 and the screw 7 by contacting the fixing plate 3 to the outside of the suspension base 4, so that the screw shaft (X axis) can be rotated. When adjusting the X-axis tilt (tilt) of the objective lens 14, the adjustment screw 24 inserted from below the fixed base 1 is attached to the suspension base 4.
It is necessary to make the adjusting screw 24 advance and retreat against the fixing force (tightening force) of the screw 7. For this adjustment work, the management of the tightening force of the screw 7 is a very important position. If the tightening force is too strong, it is difficult to adjust, and if it is weak, the adjustment position will be out of order. The work efficiency is extremely poor because of the high skill required.

In addition to the X-axis tilt adjustment described above, this optical pickup device is incorporated in an optical pickup device main body prepared to guide an optical information signal obtained from an objective lens to a photoelectric conversion element. In order to finally use the optical pickup device as a unit, it is necessary to adjust the Y-axis tilt (tilt) of the objective lens 14 with respect to the optical pickup device main body.
Since the adjustment is performed mainly on a ball (ball) disposed between the base and the base of the apparatus main body (not shown), it is difficult to perform the adjustment work again.

[0021]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has a lens provided with an objective lens.
Optical disk with holder using multiple suspension wires
To swing in the focus and tracking directions
Supported on a fixed base and integrated with the fixed base
X-axis tilt adjustment of the objective lens with respect to the optical disk
And an optical pickup device for performing Y-axis tilt adjustment, which is provided separately from the lens holder, and
A plurality of suspenders having one end fixed to the lens holder.
Left and right to support the other end of the
Projecting between the wire support portion and the left and right wire support portions.
A first protruding portion that serves as a rotation fulcrum for X-axis tilt adjustment;
Suspension base integrally formed with
Supporting the first protrusion formed on the cushion base.
A second protrusion for rotating the first protrusion in the X-axis tilt direction;
A first groove, the first groove being located near the objective lens, and
A rotation support for adjusting the Y-axis tilt substantially orthogonal to the projection
A fixed base formed with a second projection serving as a point,
Insert the lens holder with the objective lens
Swingable to the fixed base via suspension wire
Body fixed base to be mounted while supported
Supporting the second protrusion formed on the fixed base;
Second groove for rotating the projection portion in the Y-axis tilt direction
A side portion of the main body fixing base formed with
The first projection formed on the mounting base is fixed to the fixing base.
X-axis tilt adjustment in a state of being elastically biased to the base side
1 adjusting means, and the second adjusting means formed on the fixed base.
A state in which the protrusion is elastically urged toward the body fixing base.
And second adjusting means for adjusting the Y-axis tilt by
An optical pickup device is provided.

In the above invention, the suspension base is provided.
The first protrusions formed on the base and the fixed base.
The second protrusion formed is an arc-shaped protrusion, and the second protrusion is fixed.
The first groove formed in the base and the body fixing base
Characterized in that the second groove formed on the side of the groove is a V-groove.
It is assumed that. Further, the invention described above is characterized in that:
Connect one end of the pension wire to the top and bottom of the lens holder.
Fixed to intersect at a virtual intersection, and
The other end of the pension wire is "C-shaped" with respect to one end
Formed on the suspension base in the expanded state
It is characterized by being supported by the left and right wire support parts
is there.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of an optical pick-up device according to the present invention will be described below in detail with reference to FIGS.

For the sake of convenience, the same components as those described above are denoted by the same reference numerals and described.
The description of the same operation is omitted.

The structure of the optical pick-up device in which the movable member is supported on the fixed member by means of a wire stretched in a C-shape is the same as in the above embodiment. The present invention is characterized by a supporting relationship to a fixing portion serving as a base in connection with an improvement in the shape of the fixing member, and a mounting (supporting) relationship to an optical pickup device main body for constituting an optical pick-up device as a unit. Have

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIGS. 1 and 4, a position substantially symmetrical with an objective lens 14 about a virtual intersection O of a wire 10 of a lens holder 15 as a movable member 11 (a position corresponding to the auxiliary balancer 22). The object lens 14 extends toward the suspension base 40 serving as a fixing member.
Virtual intersection O and fixed member (suspension base 40)
A pair of stoppers 2 in a direction orthogonal to a straight line passing through the center of
5, 25 are integrally formed.

The concave portion 15a of the lens holder 15 for accommodating and fixing the objective lens 14 is made large in diameter so as to have a margin of about 10 μm in one radial direction of the lens, so that thermal expansion of the lens can be prevented. The mechanical stress of the lens holder 15 having a large coefficient of thermal expansion is prevented from directly acting on the lens, so that the lens is prevented from being distorted.

On the other hand, the suspension base 40 facing the end face side of the lens holder 15 is provided with a suspension base body 41 and a plurality of suspension wires 10.
It is integrally formed of a synthetic resin with a fixing plate 42 serving as a wire support . Suspension base body 41 has a stopper receiving portion 43, 43 opposing each other via the stopper 25 by a predetermined distance on one side, the grooves 1 2, 1 2 on the top and bottom surface for guiding the wire 10, 10 Each is formed. Thus, the stopper 2 in the tracking direction
Reference numerals 5 and 25 are arranged at positions separated from the objective lens 14.

That is, the stopper in the thin type optical pickup device of the present invention is the lens holder 1.
Since the reflection mirror is located immediately below the lens mounting portion 5 so as to be surrounded in an overlapped state, when the movable member performs a tracking operation, the inner surface of the lens holder 15 and the reflection mirror come into contact with each other and the optical axis This is set so as to prevent the displacement, prevent the coil of the movable member 15 from contacting the yoke, prevent the occurrence of a layer short-circuit, and secure a movable range required for tracking the lens.

More specifically, as shown in FIG. 3, radii RM and RR from a virtual intersection O corresponding to a point where the reflecting mirror M and the inner surface 15b of the lens holder 15 and the mirror M face each other, and the yoke 19 and the focus. Since the radius RS from the virtual intersection O of the stopper 25 to the radius RC from the virtual intersection O corresponding to the point facing the coil 17 is large, the influence of variations in stopper accuracy is reduced.

Further, the stoppers 25, 25
By arranging the movable member at a position apart from 4, the increase in the mass of the movable member due to the addition of the stopper function becomes a part of the balancer, thereby preventing the substantial increase in the mass of the movable member.

Further, by providing a stopper receiving portion for the stopper 25 of the movable member on the suspension base 40, which is a fixed member, there are various advantages of eliminating the influence of X-axis tilt adjustment described later on stopper accuracy.

On the other side surface of the suspension base body 41, the left and right ends of the wires 10 , 10 having one end fixed to the lens holder 15 are separately supported on the left and right.
A fixed plate 42 is disposed as a wire support . The fixed plate 42 is orthogonal to a straight line (X axis) passing through the center of the objective lens 14 and the virtual intersection O, but is inclined with respect to the X axis. It has bending elastic displacement parts 42a, 42a.

The wire 10 guided by the grooves 13 is guided into the grooves 12 on the fixing plate 42, and an ultraviolet curing adhesive (UV adhesive) is formed in the grooves 12, 12.
Is fixed at. By fixing the end of the wire 10 with the UV adhesive in this manner, the mounting distortion due to heat can be removed as compared with the above-described heating and fixing by soldering. This improves the mounting accuracy with respect to.

On the straight line (X axis) passing through the center of the objective lens 14 and the virtual intersection O in the suspension base body 41, a pair of circles for rotatably supporting the suspension base 40 on the fixed base 1. Arc projection 4
3a and 43a. The center of rotation of the arc-shaped projection 43a is substantially coincident with the plane center of the lens orthogonal to the optical axis of the objective lens 14.

The pair of arc-shaped projections 43a, 43a of the suspension base body 41 are respectively supported by V-grooves 101, 101 serving as mounting plates that are erected on the fixed base 1, and the suspension base 40 is bent in a U-shape. One side is elastically rotatably held by the fixed base 1 by the formed leaf spring 44. Due to this sandwiching, the suspension base 40 moves in the direction of rotation around the arc-shaped projections 43a, 43a toward the side where the leaf spring 44 is urged, but the end of the adjusting screw 45 screwed from the lower surface of the fixed base 1 is The mounting posture is maintained by contacting the lower surface of the suspension base body 41. Thus, by rotating the adjusting screw 45 to advance and retreat with respect to the fixed base 1, the suspension base 40 can easily adjust a fine rotation position around the X-axis around the arc-shaped projections 43a, 43a (X-axis). Tilt adjustment), and finally assembled as one optical unit. Therefore, by such mounting, it is possible to avoid the delicate management of the screw tightening force as in the above-described conventional device.

The fixed base 1 is located on a straight line perpendicular to a straight line passing through the objective lens 14, the virtual intersection O and the center of the fixed plate 3, and the central axis of the plane of the lens including the optical axis of the objective lens 14. Arc-shaped projections 46a, 46a are respectively formed on the side portions 46 so as to be rotatable about the (Y axis) as a fulcrum. On the other hand, the arc-shaped projections 46a, 46a are received on a side portion 47 of a main body fixing base of an optical pickup device main body (not shown) for accommodating one unit of the optical unit to be mounted on a device as a pickup device. A pair of V-grooves 48 for supporting rotation (the other is not shown)
Is formed.

The optical pickup device rotatably supported in the Y-axis direction by the V-groove 48 has the fixed base 1 and the lower surface of the main body fixed base bent in a U-shape (not shown) as in the above embodiment. The Y-axis tilt is easily adjusted by the advance / retreat operation of the adjusting screw inserted from the lower surface of the main body fixing base, and the Y-axis tilt is easily adjusted.

In the embodiment of the present invention, an arc-shaped projection is provided on one side for adjusting the X-axis and the Y-axis, and the other is a V-groove.
Instead of the arc-shaped projection, any shape of projection for swinging may be used, and the other side may be flat, but a groove type is preferable for stabilizing the mounting position. 1 and 2, reference numeral 49 denotes a lens cover.

Here, the operation of the present embodiment configured as described above will be described.

In the pickup device constructed as described above, when it is driven, the focus coil 1
The lens holder 24 moves in the focusing direction (optical axis direction) according to the current flowing through the tracking coil 7 and the tracking coil 18.
In this case, the disk D is accessed by moving in the tracking direction. In such a case, the provision of the damper block portion 21 having the balancer function and the auxiliary balancer 22 allows the right and left mass balance in FIG. Therefore, generation of unnecessary rotational force at the time of access can be significantly suppressed.

Further, since the fixed plate 42 is elastically displaced with respect to the suspension base body 41, unnecessary resonance is removed by the damper function between both ends, so that the damper effect at the time of driving the apparatus can be greatly improved. At the time of access, unnecessary resonance in a particularly high frequency band is almost certainly suppressed, and the Q of resonance (a symbol numerically indicating the high-frequency performance of a component) can be controlled.

According to the optical pickup device according to the present invention described in detail above, particularly, the suspension base
First formed protrusion and first groove formed in fixed base
Are used as pivot points for X-axis tilt adjustment, and
Formed on the main body fixing base and the second protrusion formed on the main body.
The second groove is used as a pivot point for Y-axis tilt adjustment.
X axis tilt adjustment and Y axis tilt adjustment are individually
X-axis tilt adjustment and Y-axis adjustment
There is an effect that Ru can make axial tilt adjustment in a short time.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing one embodiment of an optical pickup device of the present invention.

FIG. 2 is a perspective view showing an assembled state of the optical pickup device of the present invention.

FIG. 3 is an explanatory diagram illustrating an arrangement relationship of stoppers in a lens holder.

FIG. 4 is a plan view and a side view showing a relationship between a movable member and a fixed member of the optical pickup device of the present invention.

FIG. 5 is a plan view of a conventional optical pickup device.

FIG. 6 is a schematic side view of a conventional optical pickup device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Fixed base, 10 ... Suspension wire, 11 ...
Movable member, 14: objective lens, 15: lens holder, 4
0: suspension base, 41: suspension base body, 42: fixing plate, 42a: elastic displacement part, 43a:
Arc-shaped projections, 44: leaf spring, 46a: arc-shaped projections.

──────────────────────────────────────────────────続 き Continuing from the front page Examiner Masaya Tonogawa (56) References JP-A-5-20703 (JP, A) JP-A 8-10643 (JP, A) (58) Fields investigated (Int. Cl. ⁷⁾ , DB name) G11B 7/08-7/095

Claims (3)

(57) [Claims] 1. A lens holder having an objective lens mounted thereon is
Of the optical disk by the number of suspension wires
Fixed base that can swing in the tracking and tracking directions
The objective lens is supported and integrated with the fixed base.
Adjust the X-axis tilt and Y-axis
In an optical pickup device for performing tilt adjustment, the optical pickup device is provided apart from the lens holder, and
Multiple suspensions with one end secured to the lens holder
Left and right wires that support the other end of the
Protruding between the wire support portion and the left and right wire support portions.
Integrates with the first projection, which is a pivot point for shaft tilt adjustment
A suspension base formed on the suspension base and the first protrusion formed on the suspension base
To rotate the first protrusion in the X-axis tilt direction.
A first groove for positioning the objective lens,
Y-axis tilt adjustment substantially perpendicular to the first protrusion
Base with a second projection serving as a pivot point for
And the lens holder to which the objective lens is attached.
Swinging on the fixed base via a number of suspension wires
A main body fixed base mounted in a movably supported state, and the second protrusion formed on the fixed base.
A second protrusion for rotating the second protrusion in the Y-axis tilt direction;
A side portion of the main body fixing base formed with two grooves, and the first protrusion formed on the suspension base
With the X axis chilled elastically toward the fixed base side.
A first adjusting means for adjusting the distance between the first base and the second protrusion formed on the fixed base;
Y-axis tilt adjustment while elastically biasing toward the fixed base
An optical pickup device, comprising: 2. The suspension base formed on the suspension base.
A first protrusion and the second protrusion formed on the fixed base;
Before the protrusion is formed on the fixed base as an arc-shaped protrusion
Before the first groove and the side of the body fixing base are formed
2. The optical pickup device according to claim 1, wherein said second groove is a V-groove . 3. One end of the plurality of suspension wires.
Are fixed so that they intersect at virtual intersections above and below the lens holder.
And the other end of the plurality of suspension wires
With the support extended in a “C” shape to one end.
Supported by left and right wire support parts formed on the pension base
Optical pickup apparatus according to claim 1 or claim 2, wherein the the.