JPH0711866B2 - Light beam address detection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a method for detecting an address and generating a recording / reproducing timing for positioning a light beam for optically recording / reproducing information at a predetermined position on an optical disk. Regarding

[Conventional technology]

In an optical disk device, a groove called a groove is formed on the recording surface of an optical disk, and either a land area or a groove area between the grooves is used as a track for recording / reproducing information, and pre-recorded on the track. A method of reading the stored address information, moving the light beam to a desired address, and recording / reproducing the information at an arbitrary position on the optical disc is widely known and has already been put into practical use.

In addition, as a method of positioning the light beam on the track on the optical disc, like the push-pull method, the influence of the diffraction of the light beam due to the groove is detected from the reflected light when the optical beam is irradiated onto the optical disc, and the light beam is detected. The method of optically detecting the tracking position error of is generally well known.

[Problems to be Solved by the Invention]

In the conventional technique, either the land area or the groove area of the optical disk is used for recording / reproducing information, so that the address information is recorded only in one of the land area or the groove area used as a track.

Therefore, when recording / reproducing is performed on both the land area and the groove area, for example, when recording / reproducing operation is performed on the groove area of the optical disc for recording / reproducing on the land area, the address information is recorded in the groove area. However, since the address information and the recording / reproducing timing cannot be detected, there is a problem that a special optical disk in which the address information is recorded in both the land area and the groove area is required.

An object of the present invention is to solve such a problem in an optical disk device and to enable recording / reproducing in both a land area and a groove area by using an optical disk having the same format as a conventional one, and substantially reduce the track density of the optical disk. It is an object of the present invention to provide a light beam address detection method capable of increasing the recording capacity by increasing the recording capacity.

[Means for Solving the Problems]

According to the present invention, a light beam for recording / reproducing information is positioned on an optical disk in which address information is recorded in either a land area or a groove area. Therefore, the address where the light beam is located on the optical disk is detected. ,
In the light beam address detection method, two or more light beams are continuously arranged in the land area and groove area on the adjacent optical disk, and at least one light beam is an area where address information is recorded. Based on the content of the address information read from this area and the timing when the address information is detected, the position of the light beam on the area where the address information is not recorded is recognized and the recording / reproducing operation is performed. It is characterized by determining the timing of.

[Action]

In the light beam address detection method of the present invention, since two or more light beams are arranged in the continuous land area and groove area, at least one light beam is extracted from the area originally used as the information recording track. Can read the address information of the optical disk. For the light beam passing through the area where the address information is not recorded, the address information is recorded by generating the recording / reproducing timing using the address information read by the adjacent light beam and the timing thereof. Accurate recognition of addresses and generation of recording / reproducing timing are possible even for a light beam in a non-existing region.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an optical disk device for implementing a light beam address detection system according to the present invention. In this optical disk device, the optical head 1 outputs two light beams 3a and 3b corresponding to the two light emitting means 2a and 2b, respectively. The light beams 3a and 3b are reflected by the optical disc 4 and returned to the optical head 1 to receive the address signals 5a and 5b and the tracking position error signal 6 corresponding to the light beams 3a.
Is output.

As shown in FIG. 2, the light spots formed by the light beams 3a and 3b form light spots 7a and 7b on the optical disc 4, respectively. At this time, it is assumed that the address information 30 is recorded on the land area 8 and the address information is not recorded on the groove area 9 on the optical disc 4.

Here, the light beam 3a is controlled by the actuator 15 by the tracking servo means 10 so that the tracking position error signal 6 becomes zero. As a result, the light spot 7a on the optical disk 4 by the light beam 3a is always positioned on the land area 8, and the address of the light spot 7a on the optical disk 4 is the address recognition means 11 as in the prior art.
Can be read by. At this time, the recording / reproducing of the information by the light beam 3a can be considered in the same manner as the conventional optical disk device for recording / reproducing only in the land area 8.

Now consider the light beam 3b corresponding to the light emitting means 2b. Second
As shown in the figure, the light spot 7b formed by the light beam 3b is placed in the groove area 9 adjacent to the land area 8 where the light spot 7a corresponding to the light beam 3a is located.
By recognizing the address of 3a, the current position of the light beam 3b can be known.

When recording / reproducing to / from the group area 9, the controller 20
By the switching signal 21 output from the switching means 12 to the switching means 12, the input of the data reproducing means 14 is switched to the address signal 5b, and the data in the groove area 9 as well as the land area 8 can be reproduced. Similarly, a switching signal 22 output from the controller 20 to the recording control means 13 causes a light emitting means.
By selecting 2b and performing the recording operation, it is possible to perform recording on the groove area 9.

As described above, according to the present invention, it becomes possible to perform recording / reproducing in both the land area and the groove area with respect to the optical disc having the same format as the conventional one.

〔The invention's effect〕

According to the present invention, it is possible to perform recording / reproducing in both the land area and the groove area by using the optical disc having the same format as the conventional one. Therefore, it is possible to increase the capacity of the optical disc and to perform recording / reproducing with respect to the optical disc device recorded by the conventional optical disc device, so that the compatibility can be maintained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an optical disk device which implements a light beam address detection system according to the present invention, and FIG. 2 is a view showing a positional relationship between two light spots on an optical disk. . 1 ... Optical head 2a, 2b ... Light emitting means 3a, 3b ... Optical beam 4 ... Optical disk 7a, 7b ... Optical spot 8 ... Land area 9 ... Groove area 10 ... Tracking control means 11 ... Address Recognition means 12 …… Switching means 13 …… Record control means 14 …… Data reproduction means 20 …… Controller

Claims (1)

[Claims] 1. A light beam for recording / reproducing information on / from an optical disc having address information recorded on either a land area or a groove area,
In a light beam address detection method for detecting an address where a light beam is located on an optical disk, two or more light beams are successively arranged in a land area and a groove area on an adjacent optical disk, and at least 1 The light beam of the book is placed on the area where the address information is recorded, and the content of the address information read from this area and the timing when the address information is detected indicate that the address light is not recorded on the area. A light beam address detection method characterized by recognizing the position of the light beam on the disk and determining the timing of the recording / reproducing operation.