JP3227585B2 - Optical information recording / reproducing 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 information recording / reproducing apparatus for optically recording or reproducing information (including an apparatus having only a recording function, an apparatus having only a reproducing function or an apparatus having a recording function and a reproducing function). ), And more particularly, to a tilt angle adjustment mechanism of an objective lens installed in the apparatus.

[0002]

2. Description of the Related Art An optical information recording / reproducing apparatus has optical components for condensing and separating a light beam. Wavefront aberrations such as coma, astigmatism, spherical aberration, and optical axis shift may occur. In this case, the spot formed on the optical disc is affected by each aberration component and generates distortion, and this distortion causes deterioration of signal quality during recording or reproduction. In order to solve such a problem, in particular, as a method of correcting a coma aberration component depending on the tilt angle of the objective lens,
In some cases, an actuator, an objective lens, a shaft of a support section of the actuator, and a drive section magnet are unitized, and this unit is provided with a tilt adjustment function.

FIG. 4 is a perspective view showing an objective lens tilt angle adjusting mechanism of the above-mentioned conventional optical information recording / reproducing apparatus, FIG. 5 is a structural view of its components, and FIG. 6 is a sectional view of FIG. 4 and 5, reference numeral 50 denotes an optical disk; 51, an objective lens for emitting light to the optical disk 50;
Reference numeral 1 denotes an actuator unit to which the actuator unit 52 is attached. The actuator unit 52 includes a movable unit actuator, a support shaft of the actuator, and a drive unit magnet. 53 is an actuator unit 52
Inside the base 53, a semiconductor laser as a light source, a condensing lens system including a collimating lens and a condensing lens, an isolation optical system for separating and transmitting a light beam, and reflected light from the optical disc 50 are provided. An optical component including a light receiving element for receiving light is installed.
55 is an adjusting screw for adjusting the inclination angle of the actuator unit 52 with respect to the base 53, and 57 is a spring spring through which the adjusting screw 55 is inserted to support the actuator unit 51 and the base 53 with spring pressure. 59 is base 5
3 is a slide shaft for guiding the optical disk 3 in the radial direction of the optical disk 50.

Next, the connection state between the actuator unit 52 and the base 53 will be described with reference to FIG. 5
2a is a convex spherical portion provided on the actuator unit 1, and the convex spherical portion 52a is in sliding contact with the concave spherical portion 53a provided on the base 53. The radius of curvature 61 of the contact surface is configured to be the distance between the focal point formed on the optical disk 50 by the objective lens 51 and the contact surface. That is, the contact surface between the convex spherical portion 52a of the actuator unit 1 and the concave spherical portion 53a of the base 53 is in an arc shape centered on the image forming point of the objective lens 51, so that the spot position does not shift. .

Next, the operation of the conventional objective lens inclination adjusting mechanism configured as described above will be described. Base 53
The light flux between the actuator unit 52 and the actuator unit 52 is coupled by a parallel light flux, and can be focused on the optical disc 50 by focusing on the focus direction by the objective lens 51. The base 53 on which the actuator unit 52 is mounted can move around the slide shaft 59 while tracking data on the optical disk 50. For data tracking, it is necessary that the normal to the surface including the two slide shafts 59 and the normal to the surface of the optical disk 50 match.

FIGS. 7 and 8 are explanatory views for explaining a light spot image formed on the optical disk 50. FIG. 7 shows a light spot image when there is no coma aberration, and FIG. 8 shows a light spot image having coma aberration. Light spot images in each case are shown. As can be seen from the figure, when there is coma aberration, the light intensity distribution of the spot is more biased than when there is no coma aberration. Becomes Further, the same applies to the case of recording, which causes a deterioration in recording performance. Therefore, when there is coma, the actuator unit 52 operates the three adjustment screws 55 to tilt the objective lens 51, and corrects the tilt of the coma component generated due to optical component accuracy or assembly accuracy. .

[0007]

Since the conventional tilt adjusting mechanism is constructed as described above, the structure of the adjusting mechanism becomes complicated, making it extremely difficult to reduce the thickness.
Since the adjustment mechanism is complicated, the number of parts is large and cost reduction is difficult. In addition, in the case of adjusting the tilt angle by using the three-point adjusting screws, there is a problem that the adjustment is difficult due to interference between the screws during the adjustment.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an optical information recording / reproducing apparatus having an inclination mechanism capable of simplifying and thinning an adjustment mechanism and easily adjusting the inclination. The purpose is to get.

[0009]

An optical information recording / reproducing apparatus according to the present invention is provided with a base provided with a sliding shaft, and mounted on the sliding shaft on the base via a bearing sliding portion. A movable body that performs focusing and tracking of the light beam on the optical information recording carrier and performs information tracking and tracking, and irradiates the information track of the optical information recording carrier with the light beam to record or reproduce information. The bearing sliding portion has a sliding surface with the sliding shaft formed of a metal-based member, and a contact surface with the movable body formed of a plastic-based member. Joints are inclined with each other
It is formed in a curved surface shape whose angle can be adjusted .

[0010]

[0011]

In the optical information recording / reproducing apparatus configured as described above, the joint between the bearing sliding portion and the movable body is connected to each other.
Since it is formed in the shape of a curved surface whose tilt angle can be adjusted, the tilt angle between the bearing sliding portion and the movable body can be adjusted in all directions, and the coma aberration component can be corrected. In addition, the sliding surface of the bearing sliding portion formed of a metal member smoothes the sliding with the sliding shaft, and the contact surface with the movable portion formed of the plastic member is the contact surface of the sliding surface. Facilitates formation.

[0012]

FIG. 1 is a sectional view (XX section of FIG. 2 described later) showing an embodiment of the present invention. In the drawing, reference numeral 1 denotes an actuator, 3 denotes an objective lens attached to the actuator 1, and 5 denotes an objective lens. Is a bearing sliding portion. The bearing sliding portion 5 includes a cylindrical body 5a formed of a metal-based member, and a spindle-shaped plastic spherical body 5b formed on the peripheral surface of the cylindrical body 5a. Spherical body 5b
Are fixed by press-fitting or bonding. The bearing sliding portion 5 has a hole 1 provided substantially at the center of the actuator 1.
a, and the bearing sliding portion 5 and the actuator 1 are in contact with each other so that the tilt angle can be adjusted. Reference numeral 7 denotes an adhesive for fixing the actuator 1, the bearing sliding portion 5, and the cylindrical body 5a and the plastic spherical body 5b.
The adjustment is performed after the tilt angle between the actuator and the actuator 1 is adjusted. Reference numeral 9 denotes a focusing coil for focusing. FIG.
Is a plan view of the present embodiment, in which 11 is a tracking coil for tracking.

FIG. 3 is an explanatory diagram for explaining the mounting state of the actuator 1. In the figure, reference numeral 13 denotes a rubber damper, and the rubber damper 13 supports the actuator 1 and components attached to the actuator 1. Reference numeral 15 denotes a base on which the actuator 1 is mounted, 17 denotes a sliding shaft mounted substantially at the center of the base 15, 19 denotes a focusing magnet mounted on the base 15 and around the sliding shaft 17, and 21 denotes a focusing magnet. This is a set of tracking magnets attached to the side of the base 15 so as to face each other.

In the actuator 1 supported by the rubber damper 13, the rubber damper 13 is fixed to the base 15, the cylindrical body 5a of the bearing sliding portion 5 is inserted through the sliding shaft 17, and the plastic spherical body 5b is moved. By fitting into the hole 1a provided in the actuator 1, the base 15
Mounted on top. The focusing coil 9 attached to the actuator 1 and the focusing magnet 19 form a magnetic circuit to perform focusing, and the tracking coil 1 attached to the actuator 1 is formed.
1 and a tracking magnet 21 to form a magnetic circuit for tracking.

Next, a description will be given of a method of correcting the aberration by correcting the inclination of the coma. XX of the actuator 1 while monitoring the spot image to be formed with an optical microscope or the like.
There is a method of tilting the actuator 1 itself with a holding jig supporting the direction (see FIG. 2) or tilting the base 2 integrated with the sliding shaft 17 to adjust. At this time, the contact surface between the hole 1a of the actuator 1 and the plastic spherical body 5b of the bearing sliding portion 5 is spherical, and an angle can be given in all directions around the sliding shaft 17. That is, the coma aberration of the spot formed on the optical disk can be corrected by the tilt angle correction because the actuator 1 itself tilts about the sliding shaft 17. After adjusting the tilt angle, the adhesive 7 is injected into the joint between the bearing sliding portion 5 and the actuator 1 or fixed from the side surface of the actuator 1 with a screw or the like.

[0016]

As described above, according to the present invention, the joint between the bearing sliding portion and the movable body is formed into a curved surface capable of adjusting the inclination angle with respect to each other, so that the inclination angle between the bearing sliding portion and the movable body can be adjusted. As a result, the tilt adjusting mechanism of the movable body can be simplified, and the tilt adjusting mechanism can be easily thinned. Further, the inclination angle between the bearing sliding portion and the movable body can be easily adjusted in all directions. Furthermore, since the mechanism is simple, the tilt angle can be adjusted easily and accurately, and the cost can be reduced because the number of parts is small.

Further, since the sliding surface of the bearing sliding portion with the sliding shaft is formed of a metal-based member, the sliding with the sliding shaft becomes smooth. Further, since the contact surface of the bearing sliding portion with the movable portion is formed of a plastic member, the formation of the portion is facilitated.

[Brief description of the drawings]

FIG. 1 is a sectional view of one embodiment of the present invention.

FIG. 2 is a plan view of one embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating an attached state of an actuator 1.

FIG. 4 is a perspective view showing an objective lens inclination adjusting mechanism of a conventional optical information recording / reproducing apparatus.

FIG. 5 is a diagram showing a component configuration of an objective lens tilt angle adjusting mechanism of a conventional optical information recording / reproducing apparatus.

FIG. 6 is a sectional view of FIG. 4 showing a conventional example.

FIG. 7 is an explanatory diagram illustrating a light spot image formed on an optical disk 50.

FIG. 8 is an explanatory diagram illustrating a light spot image formed on an optical disk 50.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Actuator 3 Objective lens 5 Shaft bearing part 5a Cylindrical body 5b Plastic spherical body 7 Adhesive

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-263622 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G11B 7/08 G11B 7/09 G11B 7 / 095

Claims (1)

(57) [Claims] 1. A base provided with a sliding shaft, and attached to the sliding shaft on the base via a bearing sliding portion to focus a light beam on an optical information recording carrier and track information tracking. And an optical information recording / reproducing apparatus configured to irradiate an information track of an optical information recording carrier with a light beam to record or reproduce information, wherein the bearing sliding portion is configured to be the sliding shaft. sliding surface is formed by a member of the metal-based, and the contact surface between the movable member is formed by members of the plastic-based, the coupling portion of tilt adjustment with each other of the bearing sliding portion and said movable member
Optical information recording and reproducing apparatus characterized by being formed on the integer can be curved, it was.