JPH04281228A - Objective lens driving device - Google Patents

Abstract

PURPOSE:To determine the central position of the objective lens of an optical information recorder in exact alignment with the mounting holes of a base. CONSTITUTION:Two pieces of adjusting screws 4, 4 are mounted in the form of holding a track spring 3 in a slit 1a of the track spring mounting part of the base 1 in such a manner that the angle of the track spring 3 in the track direction can be adjusted.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an objective lens driving device for an optical information recording device, and more particularly to a support mechanism for a movable part that holds an objective lens.

0002

[Prior Art] Conventionally, this type of optical information recording device
In order to accurately focus the laser light emitted from the semiconductor laser onto the medium for optical recording and reproduction, the objective lens is movable in the focus direction, which is perpendicular to the medium, and in the track direction, which is the radial direction. It has a support mechanism and a drive mechanism. These supporting and driving methods generally use a supporting method using a spring or the like and an electromagnetic force using a magnet and a coil.

For example, as shown in FIG. 3, a movable member 6 that holds the objective lens 5 is coupled to the track holder 2 via a focus spring 7, and can move in the focus direction, and is connected to the track holder slit 2a. A track spring 3 is fixed to the base slit 1a by adhesive, and can be moved in the track direction. The positioning of the neutral position of the objective lens 5 in the track direction with respect to the mounting hole 1b of the base 1 was determined by the parts system and assembly system.

0004

[Problems to be Solved by the Invention] However, in the conventional mechanism described above, the focus movable assembly is positioned using a jig so that the lens has a reference position relative to the base such as the mounting hole, and the slit in the track holder and the slit in the base are Since the track spring is fixed to the lens with adhesive, there is a risk that the accurate positioning accuracy of the neutral point of the lens relative to the base in the track direction may deteriorate due to variations in the shape of the slit, shrinkage of the adhesive, etc.

[0005] In other words, if the objective lens cannot be accurately positioned with respect to the base, there will be a difference in the left and right movable distance of the movable member in the track direction, resulting in a problem that the alignment accuracy of the optical axis will become inaccurate. do.

The present invention has been made in view of the above-mentioned conventional circumstances, and therefore, an object of the present invention is to provide a novel objective lens driving device capable of solving the above-mentioned problems inherent in the conventional technology. It's about doing.

[0007]

[Means for Solving the Problems] In order to achieve the above object, the objective lens driving device according to the present invention has a track spring installed in a slit in the track spring mounting portion of the base so that the angle of the track spring in the track direction can be adjusted. The objective lens is held with screws in such a manner that the objective lens is held with screws, thereby adjusting the deviation of the neutral position of the objective lens with respect to the base in the track direction that occurs during the assembly process.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment of the present invention will be specifically explained with reference to the drawings.

FIG. 1 is a plan view showing an embodiment of the present invention, and FIG. 2 is a side view thereof.

Referring to FIGS. 1 and 2, the track spring 3
The opening of the base slit 1a of the attachment part is widened in the thickness direction of the track spring 3, and two adjusting screws 4, 4 are mounted facing each other with the track spring 3 sandwiched between the opening.

By adjusting the track spring 3 in the track direction using the adjusting screw 4, it is possible to accurately position the neutral position of the objective lens 5 with respect to the mounting hole 1b of the base 1.

0012

[Effects of the Invention] As explained above, according to the present invention,
Since the positioning of the neutral point of the lens relative to the base in the track direction can be adjusted using a screw on the track spring, it is now possible to accurately determine the position of the lens, which originally varied.

In other words, according to the present invention, the reference with respect to the base in the track direction of the lens becomes accurate, so that the left and right movement distance and characteristics are balanced left and right, and the optical head of the objective lens driving device This provides the advantage of being able to accurately align the position with respect to the axis.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the present invention.

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

[Figure 3]
FIG. 2 is a plan view showing an example of a prior art.

FIG. 4 is a perspective view of the focus movable assembly.

[Explanation of symbols]

1...Base 1a...Base slit 1b...Mounting hole 1c...Yoke 2...Track holder 2a...Track holder slit 3...Track spring 4...adjustment screw 5...Objective lens 6...Movable member 7...Focus spring 8...Magnet

Claims (2)

[Claims] 1. A movable member that holds an objective lens that focuses laser light on a recording medium, a coil that is fixed to the movable member and drives the movable member in a track direction and a focus direction, and a magnet that constitutes a base. 1. An objective lens drive device comprising a magnetic circuit comprising a yoke, the objective lens drive device comprising a mechanism for adjusting a neutral position of the objective lens in its natural state in the track direction. 2. The mechanism for adjusting the neutral position of the objective lens in its natural state in the track direction is a mechanism that adjusts the track spring in the base slit by holding both sides of the track spring in the base slit with screws and feeding the screws. The objective lens driving device according to claim 1, further characterized in that: