JPH04341987A - Optical disk device - Google Patents

Abstract

PURPOSE:To prevent a lens and a disk from colliding with each other by lifting up the disk so as to keep it apart from a pickup while focus servo is not set even in the case of an optical pickup in which distance between the disk and the lens at the time of operation is short. CONSTITUTION:At the time of the recording and the reproduction of data, the disk 17 is positioned at a position 17a, and the data is recorded or reproduced by the optical pickup 15. While the focus servo is not set, the disk 17 is moved to the position 17b, and the disk 17 and the objective lens 16 or the disk 17 and a part of the pickup 15 are prevented from colliding with each other even if the disk 17 swings or the objective lens 16 moves. When the focus servo is set, the disk 17 is returned to the position 17a.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc device for recording or reproducing audio, images, data, etc.

0002

2. Description of the Related Art FIG. 2 shows the structure around an objective lens of a conventional optical disc device.

21 is a disk surface, 22 is a disk recording surface, 23 is an objective lens, 24 is a light spot of a laser beam, 25 is an optical pickup (including the objective lens 23), 26 is a base, 27 is a disk motor, 28 is a turntable, 29 is a clamper, 30 is an upper stopper,
31 is a lower stopper.

[0004] The operation of the above configuration will be explained below. A turntable 28 is fixed to a disc motor 27 fixed to a base 26. When the disk motor 27 rotates, the turntable 28 and the disk placed on the turntable 28 also rotate.

A clamper 29 fixes the disk to the turntable 28. The laser beam emitted from the optical pickup 25 is focused by the objective lens 23, passes through the disk surface 21, and irradiates a light spot 24 onto the disk recording surface 22.

The upper stopper 30 and the lower stopper 31 are
This is to limit the movable range of the objective lens 23.

[0007] In a compact disc player, this movable range is usually about ±1 mm. This is because the disk recording surface 22 moves up and down by about 1 mm due to surface runout of the disk, external vibrations, mechanical errors in the turntable 28, and the like. That is, in order to irradiate the light spot 24, the distance between the objective lens 23 and the disk recording surface 22 or between the objective lens 23 and the disk surface 21 must be kept constant, and the focus servo must be set to maintain the distance. Therefore, when the disk recording surface 22 moves up and down, the objective lens 23 also moves up and down accordingly. Generally, the working distance is the distance between the disk surface 21 and the lens 23 when the light spot 24 is being generated.

[0008]

However, in the above-mentioned conventional optical disc device, if the working distance is about 2 mm, the upper stopper 30 and the lower stopper 31 are required to prevent physical collision between the objective lens 23 and the disc surface 21. However, as drives and optical pickups become smaller, the working distance must be reduced. When the above-mentioned upper stopper 30 and lower stopper 31 are used, it is inevitable that the lens will collide with the disk when the focus servo is not applied.

There is also a device in which a bumper is provided around the lens so that the bumper collides with the disk before the lens collides with the disk, but this has the disadvantage that the disk may be scratched or dirt may remain.

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to provide an excellent optical disc device in which the lens does not collide with the disc when the focus servo is not applied, even if the working distance is small.

[0011]

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a disk on which information is written, a disk motor that rotates the disk, and an objective lens that focuses a laser beam on the disk. Equipped with an optical pickup for reading or writing information and a mechanism for changing the relative distance between the disk and the optical pickup, the distance between the disk and the optical pickup is adjusted when information is not being read or written. This prevents some parts from coming into contact with the

0012

[Function] With the above-described structure, the present invention prevents the disc from coming close to the lens due to errors in the disc or the turntable, even when the lens comes closest to the disc, that is, even when it hits the upper stopper. and lenses are separated to avoid collision.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of an embodiment. Figure 1
, 11 is the drive case, 12 is the base, 1
3 is a disk motor, 14 is a turntable, 15 is an optical pickup, 16 is an objective lens, and 17 is a disk.

The operation of the above configuration will be explained below. When recording and reproducing data, the disk 17 is at position 17a, rotated by the disk motor 13, and the optical pickup 1
5. Laser light is focused by the objective lens 16, and data is recorded and reproduced.

When ejecting the disk 17, the disk 17 is moved to position 17a, position 17b, and position 17c in order and brought out of cover 11.

When loading the disc 17,
On the contrary, the disk 17 is sequentially moved to position 17c, position 17b, and position 17a.

[0018] When the focus servo is not applied,
Since this is the time when data is not being recorded or reproduced, there is no need to keep the disk 17 rotating.

Therefore, at that time, it is possible to move the disk 17 to position 17b. By doing so, the objective lens 16 can be prevented from colliding with the disk 17.

When applying focus servo again, the disk 17 is moved from the position 17b to the position 17a, and then the disk 17 is rotated.

[0021]

Effects of the Invention As is clear from the above embodiments, the present invention is capable of preventing the disk from colliding with a part of the optical pickup including the objective lens even when the working distance is small and the focus servo is not applied. It has the effect of being able to.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an optical disc device of the present invention.

[Figure 2] Configuration diagram showing a conventional optical disc device

[Explanation of symbols]

11 Case 12 Base 13 Disc motor 14 Turntable 15 Optical pickup 16 Objective lens 17 Disc

Claims (1)

[Claims] 1. A disk on which information is written, a disk motor for rotating the disk, and an optical pickup for reading or writing information by having an objective lens for focusing a laser beam on the disk.
A mechanism for changing the relative distance between the disk and the optical pickup, and when not reading or writing information, maintains a distance between the disk and the optical pickup so that a portion of the disk and the optical pickup do not come into contact with each other. An optical disc device characterized in that: