JPH08263848A - Objective lens inclination adjusting mechanism - Google Patents

Abstract

PURPOSE: To provide an objective lens inclination adjusting mechanism suitable for miniaturizing an optical pickup device. CONSTITUTION: A bearing part 9 and an assembled body 6' constituting a movable part other than the part 9 are mounted on a deck base together with guide rails 14, 11. The assembled body 6' whose bearing 13a is supported by the guide rail 14, and the recessed parts 8i, 8j are supported by adjustment pins 33a, 33b respectively. The adjustment pins 33a, 33b are fixed to a jig base fixing the deck base movably in the direction of Z, and the direction around the Z axis and the position in the direction of Y of the assembled body 6' are adjusted by vertically moving these two adjustment pins 33a, 33b. The bearing part 9 is positioned at the place away from an access coil 7 by a short interval 35. The assembled body 6' and the bearing part 9 are fixed to each other by injecting adhesives 36 into the interval 35 after coma aberration of an objective lens 5 is corrected by using the adjustment pins 33a, 33b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tilt adjusting mechanism for an objective lens of an optical recording / reproducing apparatus used for at least one of recording and reproducing on an optical recording / reproducing medium such as a magneto-optical disk or a CD.

[0002]

2. Description of the Related Art In an optical recording / reproducing apparatus, light emitted from a laser light source is focused on a signal recording surface of an optical recording / reproducing medium by an objective lens to record / reproduce information signals. At this time, if the optical axis of the objective lens is tilted with respect to the signal recording surface, coma aberration occurs and good signal recording / reproduction cannot be performed. Therefore, various tilt adjusting mechanisms that adjust the tilt of the optical axis of the objective lens in two directions with respect to the signal recording surface are used.

As a conventional example, an optical pickup device having an adjusting mechanism disclosed in Japanese Patent Laid-Open No. 5-303749 is shown in FIGS. 11 and 12. As shown in FIG. 11, this optical pickup device includes a support base 203 that is movable in the radial direction of an optical disc D rotated by a motor 201.
have. The support base 203 is a bobbin support member 216.
The lens bobbin 206 having the objective lens R is attached to the bobbin supporting member 216 via a flexible member 206b such as a wire.

The supporting substrate 203 is, as shown in FIG.
One side A is movably supported by a slide guide shaft 204 disposed on the sub chassis 202, and the other side B is movably supported by an inner edge 205 of the sub chassis 202. Support base 2
A height adjusting mechanism is provided on one side A and the other side B of 03, respectively. With these two sets of height adjustment mechanism,
One side A is moved in the direction of arrow a or arrow b with the slide guide shaft 204 as a fulcrum, and the other side B is moved in the direction of arrow c or arrow d with the inner edge 205 as a fulcrum, thereby being parallel to the paper surface. Objective lens R in different directions
Is adjusted without changing the height of the objective lens R.

[0005]

In the tilt adjusting mechanism of the objective lens having the structure shown in FIGS. 11 and 12, the tilt of the objective lens that can be adjusted is only in one direction, and the tilt can be set in the direction orthogonal thereto. In order to be adjustable, it is necessary to use another tilt adjusting mechanism together. Furthermore, two sets of tilt adjusting mechanisms are used in order to prevent the height of the objective lens from changing during tilt adjustment. This leads to an increase in size of the optical pickup device. That is, the tilt adjusting mechanism of the objective lens in FIGS. 11 and 12 is not suitable for downsizing the optical pickup device. In addition, even though the tilt is adjusted in only one direction,
Two sets of tilt adjustment mechanisms are used. Therefore, there is a problem that the cost becomes high. It is an object of the present invention to provide an objective lens tilt adjusting mechanism suitable for downsizing of an optical pickup device.

[0006]

An inclination adjusting mechanism for an objective lens according to a first aspect of the present invention includes an objective lens, a movable portion that supports the objective lens, and a movable portion that is movable in a first direction. , Having first and second guide members fixed to the base, and first and second bearings provided in the movable part, which are respectively guided by the first and second guide members, The movable portion has a first portion having at least the objective lens and the first bearing, and a second portion having at least the second bearing, with respect to the second portion. It is characterized in that it has means for adjusting the inclination of the first portion in two directions perpendicular to and substantially orthogonal to the optical axis of the objective lens.

In this objective lens tilt adjusting mechanism, the first portion of the movable portion having the objective lens is arranged in two directions perpendicular to and substantially orthogonal to the optical axis of the objective lens with respect to the second portion of the movable portion. The tilt is adjusted.

An objective lens tilt adjusting mechanism according to a second aspect of the present invention is fixed to a base that supports the objective lens, a movable part that supports the objective lens, and the movable part so as to be movable in a first direction. The first and second guide members, and the first and second bearings provided on the movable portion, which are guided by the first and second guide members, respectively. The fulcrum for tilt adjustment in a direction substantially perpendicular to the optical axis of the lens is the first bearing located in the direction of the optical axis of the objective lens.

In this tilt adjustment mechanism for the objective lens, the fulcrum of tilt of the movable portion is located substantially on the optical axis of the objective lens, and therefore the movement of the objective lens in the optical axis direction accompanying tilt adjustment is small.

An objective lens tilt adjusting mechanism according to a third aspect of the present invention is fixed to an objective lens, a movable portion that supports the objective lens, and a base that movably supports the movable portion in a first direction. The first and second guide members, and the first and second bearings provided on the movable portion, which are guided by the first and second guide members, respectively, and the movable portion is at least A first portion having the objective lens and the first bearing, and a second portion having at least the second bearing, the second portion being spaced apart in the first direction. It is connected to the first part at two points, and the height of the second part with respect to the first part at the two points is adjustable, and is perpendicular to the optical axis of the objective lens with the first bearing as a fulcrum. In addition, it is characterized in that the tilt can be adjusted in two directions that are substantially orthogonal to each other.

In this objective lens tilt adjusting mechanism, the height of the first portion of the movable portion having the objective lens is adjusted with respect to the second portion at two points separated in the moving direction of the movable portion. The portion of (1) moves with the first bearing as a fulcrum, and the inclination is adjusted in two directions perpendicular to and substantially orthogonal to the optical axis of the objective lens.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. First Embodiment First, a first embodiment of the present invention will be described with reference to FIGS. 1 to 5 show a first embodiment of the present invention, in which a coarse access drive device of an objective lens of an information recording / reproducing apparatus using a magneto-optical disk as a recording medium is perpendicular to an optical axis of the objective lens, In addition, an example is shown in which an objective lens tilt adjusting mechanism that adjusts the tilt of the optical axis of the objective lens is applied in the rotation directions around two axes that are orthogonal to each other.

As shown in FIG. 1 (a perspective view of the entire apparatus),
A spindle motor 3 for rotating a disc 2 is fixed to the deck base 1, and the disc 2 is positioned in a cartridge 4 having an opening 4a in the center (FIG. 2). The movable portion 6 having the objective lens 5 is supported and driven by the deck base 1 so as to be movable in the X direction, as will be described later. A fixed optical system 30 having a laser, a photodetector and the like is fixed on the deck base 1.

Further, as shown in FIG. 3 (a perspective view of the movable portion) and FIG. 4 (an exploded perspective view of the movable portion), the movable portion 6 is movable by arranging an access coil 7 wound in a quadrangular prism at the center. Part 6
The rigidity of the entire access coil 7 is mainly responsible for the overall rigidity. The carriage 8 provided on the access coil 7 is formed of a spherical epoxy resin containing silica, and has a fixing portion 8a bonded to the side surface of the access coil 7 on the Y (-) side. The surface of the access coil 7 on the Y (-) side is reinforced.

A bearing 9 on the reference side is adhered and fixed to the side surface on the Y (+) side of the access coil as will be described later, bearings 9a and 9b are formed on the bearing 9, and both ends thereof are formed on the deck base 1. The guide rail 11 (FIG. 1) fixed above is inserted. A fixing portion 8b for a mirror is formed on the Y (-) side of the fixing portion 8a, and the mirror 12 is adhesively fixed thereto. The light reflected by the mirror 12 is input to and output from the lens 5.

Below the mirror 12 of the fixed portion 8a, a driven side bearing portion 13 is located, and a guide rail 14 is provided.
(FIG. 1) is inserted into the U-shaped bearing 13a. The guide rails 11 and 14 are made of silicon carbide ceramics or stainless steel with a fluorine-based coating. The fixed portion 8a and the connecting portion 8c are the carriage 8
Are formed integrally with each other, and the bearing portion 9 and the bearing portion 1 are further formed.
The access coil 7 is mainly responsible for the rigidity between the three.
The carriage 8 may be formed by insert molding the access coil 7.

A fixing portion 8f is formed on the Z (+) side of the fixing portion 8a. The X (+) side of the fixing portion 8f is brought into contact with the X (−) side surface of the holding member 10 to be positioned and adhesively fixed.

The spring 15 provided between the holding member 10 and the holder 16 is formed by pressing a thin stainless plate into a substantially U-shape by pressing. The two springs 15
The holding member 10 and the holder 16 are respectively insert-molded with plastic.

The lens 5 is fixed to the center of the holder 16, and the focus coil 17 wound in a square shape is fixed to both sides of the holder 16 in the Y direction. Holding member 10, spring 15, holder 16, focus coil 1
7 and the objective lens 5 constitute an objective lens supporting device.

As shown in FIG. 2 (cross-sectional view showing the magnetic circuit), a center yoke 19 around which a short ring 18 is fixed is arranged in the space inside the access coil 7. Further, a magnet 20 is arranged so as to form a magnetic gap with the center yoke 19, and the magnet 20 is located inside the side yoke 21 having a substantially U-shape (Z
The side yoke 21 is fixed to the (−) side, and both ends of the side yoke 21 abut on both ends of the center yoke 19 to form a magnetic circuit for access.

On the side surface of the side yoke 21 on the Y (-) side, a magnet 22 is fixed so as to face the lower side 17a of the focus coil 17 on the Y (+) side, and the magnet 23 is on the Y (-) side. Lower side 1 of focus coil 17
It is fixed to the yoke 24 so as to face 7a. The yoke 24 is fixed on the deck base 1.

Next, the operation of the first embodiment configured as described above will be described. As shown in FIG. 2, in the focus coil 17, a magnetic field in the Y direction opposite direction acts on the upper and lower sides, and when a current is passed through the focus coil 17, a force in the Z direction is generated on these two sides, and the lens 5 is moved. It can be driven in the Z direction. At this time, the spring 15 supporting the holder 16 bends in the Z direction to drive the lens 5 in the Z direction (FIG. 3).

The access coil 7 has a magnet 2
The magnetic field generated by 0 generates a force in the X direction, and
Drive in the direction. At this time, as shown in FIG. 1, the movable part 6 includes the bearings 9a, 9b and 13a and the guide rails 11 and 14.
Slides in the X direction.

Further, as shown in FIG.
Since the magnetizing directions of 0, 22, and 23 are set, the leakage magnetic field in the vicinity of the light spot of the lens 5 on the optical disc 2 by the magnets 22 and 23 is in the Y (+) direction, and the leakage magnetic field by the magnet 20 is Y ( −) Turn to cancel each other. Therefore, the leakage magnetic field in the vicinity of the light spot of the lens 5 on the optical disc 2 becomes slightly smaller in the Y direction. Therefore, the influence on the field means (not shown) that gives a magnetic field at the time of erasing and recording information on the optical spot on the optical disc 2 is small.

Since the side yoke 21 is located in the opening 4a of the disc cartridge 4, the side yoke 21 can be brought close to the optical disc 2 and the height of the electromagnetic drive device can be reduced.

Further, as shown in FIG. 4, the carriage 8
Is composed of a fixed portion 8b for fixing the bearing portion 13 and the mirror 12, a fixed portion 8a, a connecting portion 8c, and projecting portions 8g, 8h, and thus has a simple structure with no waste. Further, since the access coil 7 mainly has rigidity between the protruding portions 8g and 8h and the bearing portion 13, the connecting portion 8c only needs to have a dimension such that resin flows during molding. Therefore, the mass of this portion may be minute.

When the movable portion 6 is driven in the X direction, warpage deformation of the entire movable portion 6 in the X and Z directions, twist deformation around the Y axis, etc. cause resonance, but the movable portion 6 is caused.
Since the access coil 7 bears the overall rigidity and the rigidity thereof is high, there is no problem. Furthermore, the access coil 7
Is a metal of copper or aluminum, and therefore has a higher elastic modulus than plastic, and can increase the frequency of these resonances.

Further, in a coil movable electromagnetic drive device, the coil is always required for the movable part, but since this coil is made to be the main structure and bears the rigidity of the whole, it is another main structure. Carriage should be minimal.

Next, the main part of the present invention will be described. As can be seen from FIGS. 2 and 3, the bearing 13 a of the driven-side bearing portion 13 has a cylindrical surface where it contacts the guide rail 14. Therefore, the guide rail 14 and the bearing 13a are in contact with each other at one point. Further, the guide rail 14 is the objective lens 5
And the Y direction position is the same. The bearing 13a is located close to the objective lens 5 in the X direction.

On the Y (+) side of the connecting portion 8c, projecting portions 8g and 8h projecting on both sides in the X direction are formed.
Conical recesses 8i and 8j having an apex angle of about 90 to 120 ° are formed on the surface on the (−) side.

The angle θ between the recess 8i, the bearing 13a and the recess 8j is about 90 °. Although θ may be about 60 to 120 °, the further away from 90 °, the greater the crosstalk at the time of tilt adjustment described later. Therefore, θ is preferably closer to 90 ° so that adjustment work can be performed easily. .

The bearing portion 9 on the reference side is formed separately from the carriage 8, and bearings 9a and 9b having a square cross section and inclined by 45 ° are formed at two locations separated in the X direction. Hereinafter, assembling of the movable portion and tilt adjustment will be described.

The assembly 6'in which parts other than the bearing part 9 of the movable part 6 are assembled, and the bearing part 9 are attached to the deck base 1 on the guide rails 14,
Assemble with 11. As shown in FIG. 5, the assembly 6'is supported on the Y (-) side by a guide rail 14 that is in contact with the Z (+) side of the bearing 13a at one point, and on the Y (+) side the tip is Z (-). ) Side, it is supported by two adjusting pins 33a and 33b having spherical surfaces that fit into the recesses 8i and 8j. At this time, the assembly 6 ′ is provided with a spring or the like at the center of the assembly 6 ′ from the Z (+) side as indicated by an arrow 32 so as not to rattle the guide rail 14 and the adjustment pins 33 a and 33 b. Can be suppressed.

The deck base 1 is fixed to a jig base (not shown), and the adjustment pins 33a and 33b are movable on the jig base only in the Z direction without rattling in the X and Y directions.

The assembly 6'is positioned by the two adjusting pins 33a and 33b and the guide rail 14 in position and rotation about the X, Y and Z axes. The bearing portion 9 is positioned with a slight gap 35 in the Y direction with respect to the access coil 7, and is pressed against the guide rail 11 from the direction of the arrow 34 by a spring or the like, and is positioned with respect to the X, Y, and Z axes. And the position of rotation is defined.

The light emitted from the laser of the fixed optical system 30 is incident on the objective lens 5 via the mirror 12, and the emitted light is incident on the detection optical system 31 such as the television camera 31. Then, the adjustment pin 33a or 3 is used to correct the coma aberration of the light emitted from the objective lens detected by the detection optical system 31.
By moving 3 b up and down to adjust the position of the assembly 6 ′ in the height direction relative to the bearing portion 9, two directions that are substantially perpendicular to the optical axis of the objective lens 5 parallel to the Z direction and are orthogonal to each other. Of the objective lens 5 with respect to the disk 2 is adjusted. That is, the α and β axes shown in FIG.
45 ° from the X and Y axes on the Y plane and orthogonal to each other
When the adjustment pin 33a is moved up and down, the assembly 6'rotates around the α axis with the bearing 13a as a fulcrum. When the adjustment pin 33b is moved up and down, the assembly 6'is
Rotates about the β axis with the bearing 13a as a fulcrum.

After adjusting the coma aberration, the access coil 7
The adhesive 36 is injected into the gap 35 between the bearing 9 and the bearing 9 to fix the bearing 9 to the assembly 6 '. As described above, with respect to the reference side bearing (defining at least two points in the guide direction), the fixed side of the support member of the objective lens is tilt-adjusted in two directions perpendicular to the optical axis of the objective lens and substantially orthogonal to the optical axis. Since the objective lens tilt adjusting mechanism that can be fixed after that is provided, the following advantages can be obtained.

1. It is not necessary to dispose a spherical surface for adjusting the tilt, a screw, a spring, or the like on the movable portion of the objective lens supporting device or the optical pickup. Therefore, the objective lens supporting device and the movable portion can be made small, thin, and lightweight, and the cost thereof can be low.

2. Center of tilt of objective lens (bearing 13
Since a) is located substantially below the objective lens, the objective lens hardly moves in the Z direction even if the inclination is adjusted by one set of inclination adjusting mechanisms. The objective lens is
Although it moves in the Y direction, since the bearing 13a can be arranged under the objective lens at a distance of, for example, about 5 to 10 mm, the objective lens moves in the X and Y directions with respect to the tilt adjustment of 0.5 °. The amount can be sufficiently reduced to 0.1 mm or less.
Furthermore, since the bearing 13a is positioned almost directly below the objective lens, the distance between the bearing 13a and the bearings 9a and 9b can be reduced, and the movable part of the optical pickup can be downsized especially in the Y direction, and the weight can be reduced. become.

3. The tilt of the objective lens can be adjusted by one tilt adjusting mechanism in two directions perpendicular to the optical axis and orthogonal to each other. Therefore, no other tilt adjusting mechanism is required, the movable part of the optical pickup can be made compact and lightweight, and the manufacturing cost can be low.

4. Since the driven side bearing 13a, which is the center (fulcrum) of tilt adjustment, has a cylindrical surface and contacts the guide rail 14 at one point, even if the assembly 6'is tilted in two directions, the bearing 13a and the guide rail 14a are adjusted. The contacting point of 14 does not change even if the contacting point moves slightly. Therefore, the slip performance does not change.

If the bearing 13a is constructed by a plane parallel to the X and Y planes, for example, the contact position and the length of the bearing 13a will be moved during tilt adjustment. Since the position and rotation of the assembly 6'with respect to the X, Y, and Z axes are determined by the two recesses 8i, 8j, the assembly 6'can be positioned with respect to the guide rail even if the bearing 6 on the reference side is not provided. The accuracy can be increased.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention. For example, the following modifications are naturally included in the present invention. Be done.

Although the sliding bearing is used in the embodiment, other bearings such as a radial bearing may be used. In the embodiment, the movable part is driven by electromagnetic drive, but a rack and pinion, a lead screw or the like may be used.

The guide rail may be integrally formed with the yoke and the deck base. In the embodiment, the laser and the like are provided separately from the movable part, but all the optical system such as the laser may be arranged in the movable part 6.

In the embodiment, the mirror 12 is arranged in the assembly 6'which is tilt-adjusted with respect to the guide rails 11 and 14. However, when the tilt is adjusted, the fixed bearing 9 is provided with an arrangement portion.
You may fix it here.

The assembly 6'is tilt-adjusted about two axes which are perpendicular to the optical axis of the objective lens and are orthogonal to each other. The bearing 13a is formed by interlocking the two adjusting pins 33a and 33b. It is also possible to adjust the tilt around the X axis and the Y axis centering around.

In the embodiment, the support spring that supports the objective lens only in the focus direction (Z direction) is used, but a support spring or the like may be configured to be movable in the focus and tracking directions.

In the embodiment, the magnetic circuit for driving the objective lens in the focus direction is arranged on the fixed-side deck base with respect to the movable portion, but it may be arranged on the movable portion. In the embodiment, the adjustment pins 33a and 33b are brought into contact with the recesses 8i and 8j of the protrusions 8g and 8h.
The inclination may be adjusted by contacting two points (access coil portions near the adjustment pins 33a and 33b in FIG. 3) on both sides of the Z (-) side in the X direction on the Y (+) side.

In this case, the carriage 8 has the connecting portion 8
Since the c and the projecting portions 8g and 8h are unnecessary, the carriage 8 can be made smaller. Second Embodiment Next, referring to FIGS. 6 and 7,
A second embodiment of the present invention will be described. In the figure, members equivalent to those already described in the first embodiment are designated by the same reference numerals. Hereinafter, the description will be given with an emphasis on a part peculiar to the present embodiment.

On the Y (+) side of the carriage 8, the mounting portion 8
1, 8k are formed to have an L-shaped cross section. The bearing portion 9 has a mounting portion 9c and a Z portion protruding in the Y (-) direction.
A mounting portion 9d that projects toward the (-) side is formed.

The bearing portion 9 and the carriage 8 are held by the spring 40 so that the mounting portion 8l and the mounting portion 9d are in close contact with each other and the spring 40 is movable therebetween. A compression spring 41 is provided between the mounting portion 8k and the mounting portion 9c.
Insert two screws 42 from the Z (-) side through the hole 8p and screw into the tap 9e. With this, by rotating the two screws 42, the distance between the mounting portion 8k and the mounting portion 9c can be adjusted.

The position of the bearing portion 9 in the X direction with respect to the carriage 8 is restricted by the two bosses 8m on the carriage 8 contacting the inside of the mounting portion 9c. Hole 8p-bearing 13
The angle formed by the a-hole 8p is set to about 90 °. 90
By setting the angle to °, it is possible to easily adjust the inclination of the optical axis of the objective lens. The angle θ may be about 60 ° to 120 °, but as the angle θ deviates from 90 °, the crosstalk at the time of tilt adjustment, which will be described later, that is, the amount of tilting in the other adjustment direction when adjusting in one direction increases. It is preferable that θ be close to 90 ° so that the above can be easily performed.

Guide rails 11, 1 on the deck base 2
By rotating the two screws 42 of the movable part 6 assembled together with 4, the position of the assembly 6'in the height direction relative to the bearing part 9 is adjusted, and the objective lens 5 is moved to the optical axis of the objective lens. The tilt can be adjusted in two directions perpendicular to the axis and orthogonal to each other.

During assembly, the bearings 9a, 9b, 13a
The bearing 9 and the assembly 6'may be lightly pressed in the Z (-) direction so that the guide rails 11 and 14 do not rattle.

As described above, the fixed portion of the supporting member of the objective lens is connected to the reference side bearing at two height-adjustable points, and the two points and the driven side bearing are located at a substantially right angle. Configured to be.

This embodiment has the following advantages. 1. Compared to the first embodiment, the movable part 6 includes screws and the like and becomes heavy, but the inclination adjusting jig has a simple structure.

2. Since the tilt adjusting mechanism is arranged at a place around the bearing where a space is available, it can be arranged in the movable part of the optical pickup even if the objective lens supporting device is small. 3. Except for the advantage 1 of the first embodiment, it has the same advantages as the first embodiment. Moreover, the same modifications as those of the first embodiment are possible.

Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIGS. 8 and 9. A hemispherical convex portion 8n is formed on the Y (+) side of the carriage 8. The position of the convex portion 8n in the X direction is the same as that of the bearing 13a.

On the Y (-) side of the bearing portion 9, there is formed a hemispherical concave portion 9f which is surface-engaged with the convex portion 8n. The convex portion 8n and the concave portion 9f are brought into contact with each other, and the screw 52 is screwed into the tap of the convex portion 8n. A compression spring 51 is inserted between the screw 52 and the bearing portion 9.

As a result, the carriage 8 and the bearing 9 are
The convex portion 8n and the concave portion 9f are slidable, and the spring 51 and the screw 5
It is temporarily held by 2. In this state, the movable portion 6 is assembled to the deck base 1 together with the guide rails 11 and 14. At this time, in the assembly 6 ', the X (-) side surface of the X (-) side connecting portion 8c' is abutted against the jig so that the assembly 6'is prevented from rotating around the Z axis.

The inclination of the objective lens 5 about the X axis is adjusted by sliding the projection 8n and the recess 9f in the Z direction and tilting the assembly 6'about the bearing 13a about the X axis. Also,
To adjust the inclination of the objective lens 5 about the Y axis, the convex portion 8n and the concave portion 9f are slid around the screw 52, and the assembly 6'is moved to the bearing 1.
The rotation is performed around the Y axis around 3a.

As described above, the bearing portion 9 on the reference side and the assembly 6'to which the supporting member of the objective lens is fixed are provided in the spherical portion 8.
By assembling with n and 9f in contact with each other, the inclination can be adjusted around two axes that are perpendicular to the optical axis of the objective lens and orthogonal to each other with respect to the reference side bearing portion.

The X-direction positions of the centers of the convex portion 8n and the concave portion 9f are preferably aligned with the optical axis of the bearing 13a and the objective lens 5. In this case, the Z of the objective lens 5 is adjusted when adjusting the tilt around the Y-axis. There is an advantage that the position in the direction is hard to change.

Further, it is preferable that the Z-direction positions of the centers of the convex portion 8n and the concave portion 9f coincide with the nodal point of the objective lens 5. In this case, the Z-direction of the objective lens 5 is adjusted when adjusting the tilt around the Y-axis. And there is no movement in the X direction.

[Modification of First Embodiment] A modification of the first embodiment will be described with reference to FIG. Carriage 8
Has a reference-side bearing portion 13 ′ below the objective lens 5. The bearing portion 13 'has two bearings 13'a and 13'b for receiving the guide rail 14, which are provided at a predetermined interval in the X-axis direction. A bearing 9 ′ on the driven side is fixed to the access coil 7 by adhesion on the opposite side of the bearing 13 ′ in the Y-axis direction. The bearing portion 9'has a U-shaped bearing 9'a.

The tilt adjustment of the objective lens 5 about the X axis is performed by rotating the assembly 6'about the X axis with the guide rail 14 as the central axis. At this time, since the center of rotation is below the objective lens 5, the objective lens 5 does not move in the Z direction.

The X (+) side surface of the fixed portion 8f and the holding member 1
The 0 (X) -side surface is a cylindrical surface centered on an axis that passes through the nodal point of the objective lens 5 and is parallel to the Y axis, and tilt adjustment about the Y axis of the objective lens 5 is This is performed by causing the holding member 10 to slide in the Z direction with respect to the fixed portion 8f.

[Summary] Although several embodiments have been described above, the present invention can be summarized as follows.

1. An objective lens, a movable part supporting the objective lens, and a movable part movably supported in a first direction,
The first and second guide members fixed to the base, and the first and second bearings provided in the movable portion and guided by the first and second guide members, respectively, The portion has a first portion having at least the objective lens and the first bearing, and a second portion having at least the second bearing, and the first portion with respect to the second portion. An inclination adjusting mechanism for an objective lens, comprising means for adjusting an inclination of a part in two directions perpendicular to and substantially orthogonal to the optical axis of the objective lens.

2. An objective lens, a movable part supporting the objective lens, and a movable part movably supported in a first direction,
The first and second guide members fixed to the base, and the first and second bearings provided in the movable portion and guided by the first and second guide members, respectively, The tilt adjustment of the objective lens is characterized in that the fulcrum when adjusting the tilt in the direction substantially perpendicular to the optical axis of the objective lens is the first bearing positioned in the direction of the substantially optical axis of the objective lens. mechanism.

3. 3. The objective lens tilt adjusting mechanism according to claim 2, wherein the means for adjusting the tilt in the two directions is provided on the second portion side of the first portion. 4. The second portion is connected to the first portion at two points separated in the first direction, and the means for adjusting the inclination in the two directions is independent of the second portion at the two points. The tilt adjusting mechanism for an objective lens according to the above item 3, wherein the height of one portion is adjustable.

5. In the fulcrum and the two points separated in the first direction, one of the two points is located on a line passing through the fulcrum in a direction orthogonal to the first direction and the optical axis direction. The tilt adjusting mechanism for an objective lens described in the fourth item.

6. An objective lens, a movable part supporting the objective lens, and a movable part movably supported in a first direction,
The first and second guide members fixed to the base, and the first and second bearings provided in the movable portion and guided by the first and second guide members, respectively, The portion has a first portion having at least the objective lens and the first bearing, and a second portion having at least the second bearing, and the first portion with respect to the second portion. When fixing the part after adjusting the tilt in at least one direction perpendicular to the optical axis of the objective lens, hold at least one of the second part and the first part using a tilt adjusting jig. A tilt adjusting mechanism for an objective lens, characterized by adjusting tilt.

7. An objective lens, a movable part supporting the objective lens, and a movable part movably supported in a first direction,
The first and second guide members fixed to the base, and the first and second bearings provided in the movable portion and guided by the first and second guide members, respectively, The part has a first part having at least the objective lens and the first bearing, and a second part having at least the second bearing, and the second part is separated in the first direction. Are connected to the first portion at two points, and the relative height direction position of the second portion with respect to the first portion at the two points is independently adjustable, and the first bearing is used as a fulcrum. A tilt adjusting mechanism for an objective lens, wherein the tilt can be adjusted in two directions perpendicular to and substantially orthogonal to the optical axis of the objective lens.

8. The fulcrum of the inclination of the first portion is the first bearing, and the objective lens and the first bearing are arranged substantially in the optical axis direction of the objective lens. A tilt adjustment mechanism for the objective lens described.

9. In the fulcrum and the two points separated in the first direction, one of the two points is located on a line passing through the fulcrum in a direction orthogonal to the first direction and the optical axis direction. The tilt adjusting mechanism for an objective lens according to the above item 8.

10. Recording or reproducing of optical recording and reproducing medium,
Alternatively, in an optical recording / reproducing apparatus used for recording and reproducing, a guide member and a movable portion movable along the guide member are provided, and the movable portion is an objective lens,
An inclination adjusting mechanism for an objective lens, which adjusts an inclination of an optical axis of the objective lens in a rotation direction around two axes which are perpendicular to the optical axis of the objective lens and are orthogonal to each other.

11. Item 11. The tilt adjusting mechanism for an objective lens according to Item 10, wherein the guide member includes first and second guide rails. 12. The movable portion has a fulcrum for tilting the objective lens below the objective lens (on the side opposite to the optical recording / reproducing medium), and the fulcrum is in contact with the first guide rail, and the tilt of the objective lens 12. The tilt adjusting mechanism for an objective lens according to the above 11, wherein the adjusting mechanism is provided at a position apart from the fulcrum.

13. 13. The tilt adjusting mechanism for an objective lens according to claim 12, wherein the fulcrum has a shape of a side surface of a cylinder orthogonal to the guide rail, and is in contact with the first guide rail.

14. 14. The tilt adjusting mechanism for an objective lens according to claim 13, wherein the fulcrum is a bearing provided on the movable portion, and the bearing contacts the first guide rail.

15. It has two height-adjustable adjusting pins, and the adjusting pins come into contact with the movable part from below to tilt the optical axis of the objective lens in a rotation direction around any two of the three-dimensional coordinate axes. The tilt adjusting mechanism of the objective lens according to the above item 12, wherein the tilt adjusting mechanism adjusts.

16. The angle between one of the two adjusting pins and the fulcrum and the other adjusting pin is 90 °.
15. The tilt adjusting mechanism for an objective lens according to the above item 15.

17. 13. The tilt adjusting mechanism for an objective lens according to claim 12, further comprising a bearing portion of the second guide rail, and two height-adjustable screws connecting the bearing portion and the movable portion. 18. Item 18. The tilt adjusting mechanism for an objective lens according to Item 17, wherein an angle between one of the two screws and the fulcrum and the other screw is 90 °.

[0085]

According to the first aspect of the present invention, the inclination of the fixed side of the support member of the objective lens with respect to the bearing on the reference side can be adjusted in two directions perpendicular to and substantially orthogonal to the optical axis of the objective lens. A mechanism is obtained, which contributes to downsizing and cost reduction of the movable portion of the objective lens supporting device and the optical pickup device.

According to the second aspect of the present invention, since the driven side bearing, which is a fulcrum for tilt adjustment, and the objective lens are arranged substantially on the optical axis, the movement of the objective lens in the optical axis direction during tilt adjustment is very small. .

According to the invention of claim 3, the height can be adjusted at two points separated in the moving direction of the bearing, and the driven side bearing is used as the fulcrum for tilt adjustment. Therefore, a tilt not requiring a special fulcrum for tilt adjustment is required. An adjustment mechanism can be obtained, which is effective in reducing the size and weight of the optical pickup device.

[Brief description of drawings]

FIG. 1 is a perspective view of an information recording / reproducing apparatus including an objective lens tilt adjusting mechanism according to a first embodiment of the present invention.

FIG. 2 is a sectional view of the information recording / reproducing apparatus of FIG.

3 is a perspective view of a movable portion of the information recording / reproducing apparatus of FIG.

FIG. 4 is an exploded perspective view of a movable part shown in FIG.

FIG. 5 is a side view of the movable part shown in FIG.

FIG. 6 is a perspective view of a movable part of an information recording / reproducing apparatus including an objective lens tilt adjusting mechanism according to a second embodiment of the present invention.

FIG. 7 is a side view of the movable portion shown in FIG.

FIG. 8 is a perspective view of a movable part of an information recording / reproducing apparatus including an objective lens tilt adjusting mechanism according to a third embodiment of the present invention.

9 is a side view of the movable portion shown in FIG.

FIG. 10 is a perspective view of a movable portion of an information recording / reproducing apparatus including an objective lens tilt adjusting mechanism that is a modification of the first embodiment.

FIG. 11 is a perspective view of an optical pickup device having a conventional objective lens tilt adjusting mechanism.

12 is a side view of the optical pickup device shown in FIG.

[Explanation of symbols]

5 ... Objective lens, 6 ... Movable part, 8 ... Carriage, 9 ... Bearing part, 11 ... Guide rail, 13 ... Bearing part, 14 ... Guide rail, 41 ... Compression spring, 42 ... Screw.

Claims (3)

[Claims] 1. An objective lens, a movable portion for supporting the objective lens, first and second guide members fixed to a base for supporting the movable portion in a first direction, and the first and second guide members. A first and a second bearing provided on the movable part, each of which is guided by a second and a second guide member, the movable part including at least the objective lens and the first bearing. And a second portion having at least the second bearing, and the first portion with respect to the second portion in two directions perpendicular and substantially orthogonal to the optical axis of the objective lens. An inclination adjusting mechanism for an objective lens, characterized in that it has means for adjusting inclination. 2. An objective lens, a movable part for supporting the objective lens, first and second guide members fixed to a base for supporting the movable part in a first direction, and the first and second guide members. And first and second bearings provided in the movable portion, which are guided by the second and second guide members, respectively, and are used when adjusting the inclination of the movable portion in a direction substantially perpendicular to the optical axis of the objective lens. A tilt adjusting mechanism for an objective lens, wherein a fulcrum is the first bearing positioned substantially in the optical axis direction of the objective lens. 3. An objective lens, a movable part for supporting the objective lens, first and second guide members fixed to a base for supporting the movable part in a first direction, and the first part. A first and a second bearing provided on the movable part, each of which is guided by a second and a second guide member, the movable part including at least the objective lens and the first bearing. And a second portion having at least the second bearing, the second portion being connected to the first portion at least at two points spaced in the first direction. The height of the second portion with respect to the first portion at the two points can be adjusted, and the inclination can be adjusted in two directions perpendicular to and substantially orthogonal to the optical axis of the objective lens with the first bearing as a fulcrum. A tilt adjustment mechanism for the objective lens.