KR100320252B1 - Optical pickup - Google Patents

Abstract

In the conventional optical pickup, the vertical length is large as a structure for adjusting the inclination of the optical axis of the objective lens. In the case where only one objective lens is supported, the base is enlarged to arrange the adjustment curved surface.

Only one objective lens 4 is supported by the adjustment base 6, and the adjustment base 6 and the fixed base 13 are elastically fitted and held by the pressing member 15. In the adjustment base 6, sliding portions 6b and sliding portions 7b and 7b located on the objective lens 4 side than the sliding portion 6b are formed. On the side of the fixed base 13, the concave curved surface 13a, 11a, 11a in which the sliding portions 6b, 7b, 7b slide is centered on a point on the optical axis L of the objective lens 4. It is formed in spherical shape. By making the radiuses of the adjustment curved surface 13a and the adjustment curved surfaces 11a and 11a different, the adjustment base 6 can be stabilized and tilt adjustment can be performed.

Description

Optical pickup {OPTICAL PICKUP}

TECHNICAL FIELD The present invention relates to an optical pickup for use in an optical disk device, and more particularly, to an optical pickup that enables tilt adjustment of an optical axis of an objective lens.

For example, an optical pickup is provided in a disc device in which an MD (mini disc), DVD (digital versatile disc) or CD (compact disc) is loaded.

The optical pickup is provided with a light emitting element such as a laser diode, and the laser light emitted from the light emitting element is condensed by the objective lens to form minute spots for signal reading or signal writing on the recording surface of the disk. In the signal reading operation, the light of the laser reflected from the recording surface of the disk is received by a light receiving element such as a pinpot diode to obtain a detection output of the signal. Further, the objective lens is freely supported by fine motion, and finely driving means for finely driving the objective lens in the focus correction direction and the tracking correction direction based on a focus error signal or a tracking error signal detected by the light receiving element. Is installed.

In such an optical disk apparatus, a rotating drive means having a turntable for rotating the disk is mounted on the instrument chassis, and the optical pickup is provided so that the optical pickup can move in the radial direction of the disk. If the optical axis of the objective lens is inclined in the radial direction or the tangential direction in this assembled state, there is a problem such that the spot image of the light received by the light receiving element is distorted, causing an offset in focus error detection and tracking error detection. In addition, a problem such as deterioration of jitter due to the inclination in the radial direction occurs.

Therefore, it is necessary to perform tilt adjustment of the optical axis of the objective lens in the state where the optical pickup is mounted. 5 is a cross-sectional view showing an example of a conventional optical pickup 30 that enables the tilt adjustment.

This optical pickup 30 has an adjustment base 31 and a fixed base 32, and the fixed base 32 is fixed to a carriage moving along the recording surface of the disc.

The support base 33 is fixed to the adjustment base 31, and the lens holder 35 is elastically supported freely by the elastic support body 34, such as a sun spring or a leaf spring extended from this support 33. As shown in FIG. The objective lens 36 is held in the lens holder 35. In addition, a coil 37 or a magnet is fixed to the lens holder 35, and a magnet opposing the coil 37 or a coil opposing the magnet is provided on the adjustment base 31 to constitute a correction driving means. The objective lens 36 is driven in the focus correction direction and the tracking correction direction by this correction drive means.

The fixed base 32 is provided with an inclined mirror 38 which connects the optical axis extending from the light emitting element and the light receiving element with the optical axis of the objective lens 36.

The concave curved surface 32a for adjustment is formed in the said fixed base 32, and the convex curved surface 31a which slides the said concave curved surface 32a is formed in the lower surface of the adjusting base 31. As shown in FIG. These curved surfaces 31a and 32a have a curvature of a predetermined radius centered on a point on the optical axis Lo of the objective lens 36 (preferably the intersection of the optical axis Lo and the main plane of the objective lens 36). It has a cylindrical surface or a spherical surface.

A spring pressing screw 39 is inserted through the through hole 31b formed in the adjusting base 31 from above, and the tip of the screw 39 is fixed to the fixing base 32 by screwing. A compression spring 41 is fitted between the head of the screw 39 and the adjustment base 31. Moreover, the adjustment screw 42 is inserted in the through-hole 32b formed in the fixed base 32 from the bottom, and the front part of this screw 42 is screwed freely in the adjustment base 31. As shown in FIG.

In the case where the concave curved surface 32a and the convex curved surface 31a are cylindrical surfaces, when the adjusting screw 42 is tightened or loosened, the curved surface 32a and the curved surface 31a are slid to move the adjusting base 31. It inclines in the arrow direction, and as a result, the inclination adjustment of the tangential direction Tan of the optical axis Lo is possible. In addition, the concave curved surface 32a and the convex curved surface 31a are spherical surfaces, and the adjustment screw 42 is provided in two places, and the optical axis Lo is tightened or loosened by tightening or loosening the respective adjustment screws 42. Tilt can be adjusted in both tangential and radial directions.

However, the above conventional optical pickup 30 has the following problems.

(1) In Fig. 5, since the concave curved surface 32a and the convex curved surface 31a constituting the sliding portion for adjustment are formed just below the objective lens 36, it is difficult to reduce the height dimension of the entire pickup. .

(2) In the thing shown in FIG. 5, the correction drive means which has the support body 33 on one side and the coil 37 etc. on the other side is provided between the optical axis Lo, and the adjustment base 31 and the fixed base 32 are provided. Since the dimension in the left-right direction of FIG. 5 is large across the optical axis Lo, the curved surfaces 31a and 32a extending from the left and right about the optical axis Lo can be formed. However, in the case of one supporting structure in which a correction driving means made of a coil and a magnet is provided between the lens holder 35 and the support 33, the adjustment base 31 and the fixed base 32 are smaller than the optical axis Lo. It will be placed to one side. Therefore, it is difficult to arrange the curved surface for adjustment directly under the objective lens, and the arrangement makes the adjustment base 31 and the fixed base 32 unnecessarily large. That is, the structure shown in Fig. 5 is limited in the degree of freedom of design.

(3) In the optical pickup 30 shown in Fig. 5, the adjustment base 31 is pressed against the fixed base 32 by the expansion elastic force of the compression spring 41, but the fixed base 32 is not increased unless this pressing load is increased. The adjustment base 31 cannot be stabilized on the phase. Therefore, the adjustment base 31 may deform | transform by the said pressing load. In order to prevent this deformation, the rigidity of the adjustment base 31 is inevitably increased, and the adjustment base 31 becomes large in weight, which hinders the weight reduction and increases the product cost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an optical pickup capable of accurately adjusting the inclination of the optical axis, increasing the degree of freedom in design, and miniaturizing, reducing the weight, and reducing the cost. do.

1 is a longitudinal sectional view showing an optical pickup of the present invention.

2 is an exploded perspective view showing the optical pickup of the present invention.

3 is a partially omitted perspective view showing the optical pickup of the present invention.

4 is an end view seen from the direction A of FIG.

5 is a cross-sectional view showing a conventional optical pickup.

Explanation of symbols on the main parts of the drawings

One … Adjustment moving part 2. Fixture

3…. Carriage 4... objective

5... Correction driving means 6. Fixed base

6a. Convex sphere 6b... Sliding part

7. Projection 7a... Convex sphere

7b. . Sliding part 8. Insertion hole

9. Adjusting member 11a. Adjustment surface

12... Through hole 13. Fixed base

13a. Adjustment surface 14. Wire (elastic support)

15... Pressing member 16. Cutout

17. Protrusion

The optical pickup of the present invention has an adjustment base equipped with a correction driving means for supporting the objective lens in a movable state and moving the objective lens, and a fixed base supporting the adjustment base, wherein the adjustment is performed from the side of the optical axis of the objective lens. One side of the base and the fixed base is provided with a sliding portion for sliding the sliding surface and the adjustment surface on the other side, the adjustment surface has a curvature of a predetermined radius around the point on the optical axis and the optical axis is radial and tangential It is formed toward the direction which can be tilt-adjusted to at least one of a direction, and it is characterized by the holding means which hold | maintains the said adjustment base and a fixed base after the said inclination adjustment.

In the said means, since the adjustment curved surface and the sliding part are provided in one side rather than the optical axis of an objective lens, pick-up can be made small compared with arrange | positioning the said adjustment curved surface directly under an objective lens.

Further, the adjustment curved surface may be a cylindrical surface capable of tilting the optical axis of the objective lens in the radial direction or the tangential direction, or may be a concave spherical surface which can freely tilt the optical axis in both the radial direction and the tangential direction as described below.

The center of curvature of the adjustment curved surface may be on the optical axis of the objective lens, but the center of curvature is preferably a position close to the objective lens, and more preferably, the center of curvature is the intersection of the optical axis of the objective lens and the main plane of the objective lens. Or near it.

For example, a sliding part may be provided in the adjustment base, a concave adjustment curved surface may be provided in the fixed base, or a convex adjustment curved surface may be provided in the adjustment base and a sliding part may be provided in the fixed base. In each of the above cases, the sliding portion may be a convex curved surface, a concave curved surface or a convex or concave rail shape curved in one direction, or may be a protrusion having a hemispherical tip.

It is preferable that the said adjustment curved surface consists of several curved surfaces of different curvature centering on the point on an optical axis, and the sliding part which slides each of these curved surfaces is provided.

By setting the sliding points on each of the curved surfaces having different curvatures, the adjustment base can be tilted and adjusted more stably than setting the sliding points on the curved surfaces of the same curvature when the adjustment curved surfaces are disposed to one side from the optical axis.

Furthermore, the objective lens is supported only on one side with the elastic support interposed on the adjustment base, and the correction driving means is disposed between the objective lens and the support of the elastic support, and the adjustment curved surface and the sliding portion are optical axes of the objective lens. Rather, it may be provided on the support side of the elastic support.

In the said means, since the adjustment curved surface and the sliding part provided between the adjustment base and the fixed base are arrange | positioned to one side than the said optical axis, the coil and the magnet which comprise correction drive means are comprised between the objective lens and the support part of an elastic support body. Even if disposed, the optical axis of the objective lens can be tilted in the tangential direction and / or the radial direction. In addition, since there is no need to install an adjustment curved surface directly under the objective lens, and the adjustment base and the fixed base do not need to be made larger than necessary, miniaturization can be achieved, and the thickness can be reduced.

Moreover, in this invention, it is preferable that the said adjustment curved surface and a sliding part slide at least 3 points.

When the sliding point of the adjustment curved surface and the sliding part is formed in three places, the adjustment base can be adjusted inclined stably.

For example, in the case of sliding at three points, one of the sliding points is formed at the position farthest from the center of the point on the optical axis, and the remaining two points are formed at a position closer to the objective lens than the position. Or forming one point at a position far from the center and two other points at a position close to the center is preferable in terms of stably supporting the adjustment base on the fixed base.

Moreover, in this invention, it is preferable that the said adjustment curved surface is a concave spherical surface, and a sliding part slides this concave spherical surface, and inclination adjustment to both a radial direction and a tangential direction of the said adjustment base is possible.

Moreover, it is preferable that the said holding means is a spring member which presses an adjustment base and a fixed base between the said adjustment curved surfaces.

As the holding means, after adjusting the inclination of the optical axis using the adjustment curved surface and the sliding portion, the adjustment base and the fixed base may be adhesively fixed using UV adhesive or the like, or the adjustment base may be sandwiched between the adjustment base and After adjusting the fixing base, it may be fixed by screws. Alternatively, the spring can be fixed by sandwiching the adjustment base and the fixed base with a spring member. If the adjustment base and the fixed base are held with the adjustment curved surface in this way, the work for the adhesive fixation or the screw tightening fixation after the adjustment is unnecessary. Moreover, it is not necessary to make rigidity of an adjustment base higher than necessary, and thickness reduction and tilting can be aimed at.

In addition, when the adjustment base and the fixed base are sandwiched and held by the spring member as described above, the adjustment base is tilted and adjusted as it is, and the adjustment base is left as it is by the spring member after the adjustment is completed. And maintenance of the fixed base can be continued. In this case, after the adjustment is completed, the adjustment base and the fixed base may be adhesively fixed with a UV adhesive or an anaerobic adhesive.

Furthermore, it is preferable that adjustment means for sliding the sliding part on the adjustment curved surface is provided. In this case, it is preferable that the adjustment means is provided with an adjustment member provided on the sliding part side and an adjustment screw for sliding the adjustment member. Do.

For example, a pressing member is provided on the adjusting member to pressurize the adjusting member always in one direction, and a screw is attached to the adjusting member to which the front end abuts, and the sliding portion is tightened or loosened by tightening or loosening the adjusting screw. It can be tilted by sliding on the adjustment surface.

As described above, the present invention can also be applied to a structure in which only one objective lens is supported, thereby increasing the degree of freedom in design. In addition, the adjustment base can be kept stable and can be downsized. In addition, cost reduction can be achieved because a large amount of adjustment fixtures and the like are not required for positioning, and the equipment can be simplified.

Embodiment of the Invention

EMBODIMENT OF THE INVENTION Hereinafter, the optical pickup of this invention is demonstrated with reference to drawings.

1 is a partially omitted cross-sectional view showing an optical pickup of the present invention, FIG. 2 is an exploded perspective view showing an optical pickup, FIG. 3 is a partially omitted perspective view showing an optical pickup, and FIG. 4 is a view in the direction A of FIG.

The optical pickup 10 shown in FIG. 1 is comprised by the adjustment movable part 1, the fixed part 2, and the carriage 3 which mounts the adjustment movable part 1 and the fixed part 2. As shown in FIG. The carriage 3 is moved by the pick-up transfer mechanism (slit mechanism) along the recording surface of the disk along the radial direction of the disk (from the inner peripheral surface to the outer peripheral surface side).

As shown in FIGS. 1-3, the adjustment movable part 1 is provided with the objective lens 4 and the correction drive means 5 on the adjustment base 6. As shown in FIG. The proximal end of the four wires 14 constituting the elastic support is fixed to the support portion 6c of the adjustment base 6, and is supported in a state in which only one side of the lens holder 4a is supported in front of the wire 14. The objective lens 4 is held in the lens holder 4a. In FIG. 1, the optical axis of the objective lens 4 is indicated by L. In FIG.

The correction drive means 5 is disposed in the middle of the support portion 6c and the lens holder 4a. This correction drive means 5 is a moving magnet system, a coil 5a consisting of a tracking coil and a focusing coil is provided on the adjustment base 6 side, and the magnet 5b is provided on the lens holder 4a. By the correction current applied to the coil 5a, the lens holder 4a and the objective lens 4 are focused in the focusing direction (symbol F direction in FIG. 1: up and down direction) and tracking direction (symbol T direction in FIG. 1: ground plane). In the direction perpendicular to the direction of rotation).

As shown in FIG. 3, the back center part of the adjustment base 6 is formed with the convex spherical surface 6a, and the sliding part 6b which consists of a hemispherical protrusion toward the back from a part of the said convex spherical surface 6a is integrated. It is formed. Further, the lower end of the convex spherical surface 6a is provided with an integrally protruding rectangular adjustment member 9.

As shown in FIG. 2, the linear slit insertion hole 8 is drilled in the bottom face of the adjustment base 6. In addition, two projections 7 and 7 protruding outward are integrally formed at both ends of the bottom of the adjustment base 6. Convex spherical surfaces 7a and 7a are formed at portions facing the fixing part 2 of the projecting portions 7 and 7, respectively, and sliding portions 7b comprising hemispherical protrusions on a part of the convex spherical surfaces 7a and 7a. , 7b) are integrally formed (see FIG. 3).

The fixed part 2 has the fixed base 13 formed in substantially concave shape, as shown to FIG. The concave spherical adjustment curved surface 13a is formed in the position which opposes the said convex spherical surface 6a (sliding part 6b) of this fixed base 13. The concave spherical adjustment curved surfaces 11a and 11a opposite to the convex spherical surfaces 7a and 7a (sliding portions 7b and 7b) are formed at both ends of the protruding portions 11 and 11 of the fixed base 13. Is formed. In addition, a part of the adjustment curved surface 13a is formed with a rectangular through-hole 12 having a size sufficient to allow the adjustment member 9 to be inserted therethrough.

As shown in FIG. 1, in the state which the adjustment movable part 1 and the fixed part 2 were combined, the said adjustment curved surface 13a in which the sliding part 6b provided in the adjustment base 6 was formed in the fixed base 13 is shown. A sliding part 7b provided in the adjustment base 6 abuts at two points on the adjustment curved surfaces 11a and 11a. As a result, the adjustment base 6 can slide at three points with respect to the fixed base 13.

In a state where the adjustment base 6 is provided on the fixed base 13 with the three points interposed above, the adjustment curved surface 13a is centered on one point on the optical axis L of the objective lens 4. It has a concave spherical surface having a predetermined radius of curvature. Similarly, the adjustment curved surfaces 11a and 11a are also concave spherical surfaces having a predetermined radius of curvature around the one point. The center of curvature of the adjustment curved surface 13a and the center of curvature of the adjustment curved surfaces 11a and 11a coincide. However, the curvature radii are different in the adjustment curved surface 13a and the adjustment curved surfaces 11a and 11a, and the curvature radii are shorter in the adjustment curved surfaces 11a and 11a. That is, the adjustment curved surface 13a and the adjustment curved surfaces 11a and 11a are located on the spherical surface of concentric and different radius. Moreover, the adjustment curved surface 13a and the adjustment curved surface 11a, 11a may be located on the same spherical surface.

The center of the radius of curvature may be on the optical axis L or almost on the optical axis L, and it is preferable that the center of the radius of curvature is close to the objective lens 4, and most preferably, the center is the optical axis L and the objective lens ( 4) is the intersection with the main plane.

The pressing member 15 is used as a holding means for holding the adjustment movable part 1 and the fixed part 2 mutually. The pressing member 15 is made of a concave plate spring-like elastic pressing member whose longitudinal section is formed so as to have a pressing force in a direction in which the surfaces 15a and 15b face each other. The projection part 17 is provided in the outer surface 15a on the side of the adjustment movable part 1 outside. The protrusion 17 is flexible and is bent by pressing the protrusion 17 inward. Moreover, the cutout part 16 of the magnitude | size which has a sufficient margin with respect to the adjustment member 9 is formed in the surface 15b by the side of the fixed part 2 when the adjustment member 9 is penetrated.

As shown in FIG. 1 and FIG. 4, in the fixed part 2, between the carriage 3 (or the fixed base 13 may be supported) and the adjusting member 9 supporting the fixed base 13. The coil spring 23 is provided in this. The adjusting member 9 integrally protruding from the adjusting base 6 protrudes backward through the through-hole 12 formed in the fixed base 13. The adjusting member 9 is provided with a catching portion 9a to catch one end of the coil spring 23 and the other end of the coil spring 23 to catch the catching portion 3c provided in a part of the carriage 3. have. As a result, the adjusting member 9 is always in a state of being pressed in the direction of the arrow P in FIG.

Further, as shown in FIG. 4, two adjusting screws 21 and 22 are provided at the rear end of the adjusting member 9, and the front end thereof is in contact with the adjusting member 9. The adjustment screws 21 and 22 are provided in the screw mounting parts 3a and 3b formed in the carriage 3, respectively.

1 and 4, the adjusting screw 21 adjusts the adjusting base 6 in the tangential direction Tan, and the adjusting screw 22 adjusts the adjusting base 6 in the radial direction Rad. To adjust. The coil spring 23 imparts a pressing force to the adjusting member 9 in the middle direction (P direction) of the adjusting direction, so that the adjusting member 9 adjusts with each adjusting screw 21. It is pressed against the tip of the screw 22.

Next, the assembly method of the optical pickup 10 of this invention is demonstrated.

As shown in Figs. 1 to 3, the adjusting movable part 1 and the fixing part 2 are assembled, and then the pressing member 15 is used to hold the fixing base 13 and the adjusting base 6.

That is, the convex spherical surface 6a (sliding part 6b) of the adjusting base 6 opposes the adjusting curved surface 13a of the fixing part 2, and at this time penetrates the adjusting member 9 extending from the convex spherical surface. It penetrates into the hole 12 and protrudes to the rear of the fixed base 13. When the adjustment movable part 1 is completely combined with the fixed part 2, the sliding part 6b of the adjustment base 6 abuts on the adjustment curved surface 13a of the fixed base 13 so that a sliding movement is possible, The sliding parts 7b and 7b of the base 6 abut against the adjustment curved surfaces 11a and 11a of the fixing part 2 so as to be slidable. That is, the adjustment base 6 and the fixed base 13 abut on three points with the concave curved adjustment surface 13a and the adjustment curved surfaces 11a and 11a interposed therebetween.

In addition, one surface 15a of the pressing member 15 is inserted into the insertion hole 8 formed in the adjustment base 6 from the bottom, and the other surface 15b is formed on the rear surface of the central portion of the fixed base 13. It comes in contact with the curved surface 13b. When the pressing member 15 is plugged in from below, the adjusting member 9 enters into the cutout 16 formed in the surface 15b of the pressing member 15. When the surface 15a of the pressing member 15 is inserted into the insertion hole 8, when the projection 17 is bent by the insertion force and fully inserted to the position shown in Fig. 1, the cavity portion in the adjustment base 6 The projection 17 is returned to its original state from the inside, and the pressing member 15 is locked so that it does not come off from the adjusting base 6. At this time, the adjusting base 6 and the fixed base 13 are held by the elastic force of the pressing member 15, and the sliding portions 6b, 7b, 7b and the adjusting curved surfaces 13a, 11a, 11a are always mutually different. Is pressurized.

In addition, the through hole 12 formed in the fixed base 13 and the cutout portion 16 formed in the pressing member 15 are opened sufficiently larger than the cross section of the adjusting member 9, so that the adjusting member 9 has a through hole. It is possible to move in (12) and notch (16). The opening area of the through hole 12 and the cutout 16 is a size through which the engaging portion 9a provided in the adjusting member 9 can pass. Alternatively, the locking member 9a may be attached to the adjusting member 9 after the adjusting member 9 is inserted through the through hole 12 and the cutout 16.

Further, each end of the coil spring 23 is hooked to the engaging portion 9a provided on the adjusting member 9 and the engaging portion 3c on the carriage 3 side, and at the same time or before adjustment with the adjusting screw 21. A screw 22 is provided so that its tip abuts on one surface of each of the adjusting members 9.

Next, the adjustment method of the optical pickup of this invention is demonstrated.

The adjustment method in this case is performed by operating the adjusting screws 21 and 22. As shown in Fig. 4, when the adjusting screw 22 is rotated in the R (+) direction, that is, in the direction of loosening the screw with respect to the screw mounting portion 3b, the adjusting member 9 is applied to the pressing force of the coil spring 23. To the R (+) direction. For this reason, the adjustment movable part 1 rotates circularly along the adjustment curved surface 13a, 11a, 11a to the plus (+) side of Rad direction (radial direction). On the contrary, if the adjusting screw 22 is rotated in the R (-) direction, that is, in the direction of tightening the screw with respect to the screw mounting portion 3b, the adjusting member 9 is applied to the pressing force of the coil spring 23. In the R (-) direction. For this reason, the adjustment movable part 1 rotates circularly to the negative (-) side of Rad direction.

When the adjusting screw 21 is tightened in the T (-) direction, the adjusting member 9 adjusts to the negative (-) side of the Tan direction (tangential direction) shown in FIG. 1 against the pressing force of the coil spring 23. It rotates circularly along the curved surface 13a, 11a, 11a. In addition, when the adjusting screw 21 is released and moved in the T (+) direction, the adjusting member 9 receives the pressing force of the coil spring 23 and moves in an arc shape to the positive (+) side in the Tan direction shown in FIG. .

Between the upper limb adjustment operations, the fixed base 13 and the adjustment base 6 are held by the elastic clamping force of the pressing member 15 with the adjustment curved surface 13a interposed therebetween. Therefore, the sliding parts 6b, 7b, 7b formed in the adjustment movable part 1 slide the adjustment curved surface 13a, 11a, 11a of the fixing part 2, respectively.

In the adjustment, the adjustment base 6 rotates along the spherical trajectory around the point on the optical axis L. As shown in FIG. Therefore, the optical axis L of the objective lens 4 provided in the adjustment movable part 1 inclines in a tangential direction and a radial direction. By carrying out the adjustment in the state where the carriage 3 constituting the fixing part 2 is installed in the chassis of the disk apparatus, the above-described recording surface of the disk provided on the rotation drive means (turn table) formed in the chassis. Inclination adjustment of the optical axis L becomes possible.

After the adjustment is made, the posture of the adjustment base 6 is stabilized by the elastic force of the coil spring 23 shown in FIG. 4, and the fixed base 13 and the adjustment base 6 are held by the pressing member ( 15), the tilt of the optical axis L after the adjustment does not occur. And since the curvature radius of the adjustment curved surface 13a and the adjustment curved surface 11a differs, and a sliding part slides each said adjustment curved surface, even if the adjustment base 6 is the structure supported only at the right side of FIG. ) Support is stable.

In addition, after the adjustment, the fixing base 13 and the adjusting base 6 may be fixed with an adhesive, and both of the bases 13 and 6 may be stopped by screws.

The optical pickup 10 of the present invention is not limited to the above embodiment, and the adjustment curved surface may be provided on the adjustment base side with the sliding portion on the fixed base side, and the number or position of the sliding portion and the adjustment curved surface may be changed as appropriate. have.

And although the through-hole 12 is formed in the fixed base 13 in the said embodiment, it is also possible to make the adjustment member 9 protrude from the lower surface of the fixed base 13, without forming the through-hole 12. have.

As described above, the optical pickup of the present invention does not need to provide an adjustment curved surface directly under the objective lens, and the whole can be made thin because the adjustment curved surface can be provided on one side with respect to the optical axis of the objective lens.

Moreover, even if it is a structure which supports only one side provided with the correction drive means between the objective lens and the support end of the elastic support, it is not necessary to enlarge the fixed base or the like, and the adjustment base can be tilted with good accuracy.

In addition, since it is not necessary to pressurize the adjustment base and the fixed base with a strong spring as in the prior art, it is not necessary to make the adjustment base or the like excessively high in rigidity, and the whole can be made light in weight.

Claims (8)

The adjustment base and the fixed base which have an adjustment base equipped with the correction drive means which supports an objective lens in a movable state, and slides an objective lens, and the fixed base which supports this adjustment base, and are located to the side of the optical axis of the said objective lens. The sliding surface is provided on one side of the control surface, the sliding portion for sliding the adjustment surface on the other side, the adjustment curved surface has a curvature of a predetermined radius around the point on the optical axis and the optical axis at least in the radial direction and the tangential direction It is formed toward the direction which can be tilt-adjusted to one side, and the holding means which hold | maintains the said adjustment base and a fixed base after the said inclination adjustment is provided, It is characterized by the above-mentioned. The optical pickup according to claim 1, wherein the adjustment curved surface comprises a plurality of curved surfaces having different curvatures centered on a point on an optical axis, and a sliding portion for sliding the plurality of curved surfaces, respectively, is provided. The objective lens of claim 1, wherein only one side of the objective lens is supported on the adjustment base with the elastic support interposed therebetween, and the correction driving means is disposed between the objective lens and the support of the elastic support, and the adjustment curved surface and the sliding portion An optical pickup, which is provided on the support side of the elastic support rather than the optical axis of the objective lens. The optical pickup according to any one of claims 1 to 3, wherein the adjustment curved surface and the sliding portion slide at at least three points. The optical pickup according to claim 1, wherein the adjustment curved surface is a concave spherical surface, and the sliding portion slides the concave spherical surface so that the inclination adjustment in both the radial direction and the tangential direction of the adjustment base is possible. The optical pickup according to claim 1, wherein the holding means is a spring member which presses the adjustment base and the fixed base between the adjustment curved surfaces. The optical pickup according to claim 1, wherein adjustment means for sliding the sliding portion to the adjustment curved surface is provided. 8. The optical pickup according to claim 7, wherein the adjustment means is provided with an adjustment member provided on the sliding portion and an adjustment screw for sliding the adjustment member.