JPS6220139A - Optical disk device - Google Patents

Abstract

PURPOSE:To read information at any position out of a disk at high speed by recording and reproducing alternately information on front and back faces in time series. CONSTITUTION:The faces of disks 3 and 2 of an optical disk 10 are assumed to be a front and back, respectively, and the information X is slit into four blocks A-D. The blocks A and C are recorded on the recording film of the disk 3 being a front, and the blocks B and D are recorded on the recording film of the disk 2 being a back. Then, during the same rotation, the group of the blocks A and B and that of the blocks C and D are simultaneously recorded on inherent faces. Thus the time necessary for recording can be halved. At reproduction, data on the blocks A and B and that on the blocks C and D can be simultaneously reproduced, thereby shortening the reproducing time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an optical disc device, and particularly to an optical disc device suitable for high-speed recording and reproduction.

[Background of the invention]

The conventional device is Hitachi Hyoron VOL, 65N (1, 10 (1
983-10) As in P23-P28, recording and playback are performed only from one side of the disc, and when recording and playback is performed on the back side, stop the rotation of the disc, turn it over, and then record and playback. There is. On the other hand, if optical heads for recording and reproduction are arranged on both sides of the disk, the speed can be increased, but two sets of optical heads and their driving parts are required each, making the apparatus expensive.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of these conventional examples and to provide an inexpensive optical disc device that can perform high-speed recording and reproduction.

[Summary of the invention]

In order to achieve such an object, in the present invention, optical heads are provided on one drive stand for the front and back sides of an optical disk, and these two optical heads are arranged on one drive stand, and optical heads are provided for the front and back sides of the optical disk. It is characterized by recording and reproducing information alternately in chronological order.

According to the present invention, information at any arbitrary position can be read from a disc at high speed, and since only one drive device is required, an inexpensive optical disc device can be realized.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure shows an example of an optical disc used in the present invention. This optical disc 1o has two transparent substrates (discs) 2 and 3 with a recording film 1 on one surface.

The respective recording films 1 are placed facing each other and assembled by adhesion via spacers 4 and 5. The disk 3 side of the optical disk 10 is the front side, and the disk 2 side is the back side, and the information X is divided into four blocks A, B, C, and D as shown in FIG.
, C are recorded on the recording film of the disk 3, which is the surface, and B, D
shall be recorded on the recording film of disk 2, which is the back side,
If this is done during the same rotation, blocks A and B are simultaneously recorded, and blocks C and D are simultaneously recorded on their respective surfaces.

The time required for recording is halved. Similarly, when it comes to playback, the playback time can also be shortened by playing back the data of blocks A and B and blocks C and D at the same time. Third
In the figure, optical heads 6 and 7 having lenses 9 for focusing light at their tips are arranged on both sides of an optical disk, and these two optical heads are connected to one drive system 8.

The two optical heads 6.7 each have a fine tracking mechanism so that they can read and write information at approximately the same radial position on the disk, and each optical head has a fine tracking mechanism that allows the recording and
The reproduction area can be covered by one drive system 8.

Although the information X is divided into four parts in this embodiment, it is not limited to this, and may be divided into two or more. Also, recording was done alternately on the front and back sides, but for example, A and B were recorded on the front and
C and D may be recorded on the back side.

Furthermore, the track-circumference of the optical disc is divided into multiple parts,
(Each one is called a sector.) If the above-mentioned information is divided into blocks for each sector, information management becomes easier. In addition, if the two disks 2 and 3 are assembled into a sphere whose sectors on the front and back sides are at approximately the same position when viewed from the respective optical heads, it is possible to read and write information easily.
The waiting time can be minimized and a high-speed optical disk device can be realized.

In the explanation so far, one set of optical discs has been described, but if a plurality of pieces of information are divided and recorded over a plurality of discs, the speed can be further increased several times.

In addition, information Xi, X2. If X3... is written, Xi,
X3. For example, X5... is recorded on the surface, and X2°X4.
A high-speed optical disc device can also be made by recording and reproducing X6... on the back side.

〔Effect of the invention〕

As explained above, according to the present invention, information is divided,
Since recording and reproduction can be performed simultaneously on the front and back sides of the disc, the speed can be doubled compared to the conventional method. Moreover, the two optical heads for this purpose can cover the area from the inner periphery to the outer periphery of the disk using a single drive system, making it possible to realize an inexpensive optical disk device.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an example of a double-sided optical disk used in the present invention, FIG. 2 is a view showing an example of an information arrangement, and FIG. 3 is an example of the relationship between the optical head and the disk in the optical disk device of the present invention. FIG. 1... Record Q II'J, 2, 3... Disc, 6,
7... Optical head, 8... Head feed drive system.

Claims (1)

[Claims] 1. An optical disc device having an optical disc having a recording film on both sides and an optical head on both sides of the recording film, in which information is recorded on both sides in a time-series manner. An optical disc device characterized by: 2. An optical disc device according to claim 1, characterized in that information is recorded by dividing the information into sectors in chronological order. 3. The optical disc device according to claim 1, wherein the optical heads on both sides are moved by one drive system.