Optical disk recording medium

Abstract

The present invention provides an optical disc recording medium capable of stable tracking servo and high-density recording and reproduction, an optical disc device of the medium, and a standard original disc manufacturing method of the medium. The optical disk recording medium of the present invention has on the disc-shaped magneto-optical recording medium, the groove portion that is arranged in spiral shape and concentric circle shape, the groove portion, is arranged on the groove portion and the groove portion again, is divided into a plurality of A data recording area of ​​a sector and a plurality of pre-pit areas of a pair of wobbled pits are arranged between the data recording areas.

Description

technical field [0001] The present invention relates to an optical disc recording medium which utilizes the temperature rise generated by laser irradiation to record and erase information, and uses the magneto-optical effect to read out recorded signals, the optical disc device for recording and reproducing, and its standard original disc manufacturing method. Background technique [0002] In the past, as an optical memory that irradiates an information recording medium with a light beam and detects its reflected light to reproduce information, such as a ROM-type memory that uses phase pits to record information, and a primary memory that uses light beams to open holes in the recording film to record information. Write-once (WRITE ONCE) optical memory, a phase-change optical memory that uses light beam irradiation to change the crystal phase of the recording film for recording, and a magneto-optical memory that uses light beam irradiation and an external magnetic field to cha...

AI Technical Summary

Problems solved by technology

However, in the conventional optical disc recording medium, in order to obtain the guide signal for tracking, the track pitch cannot be lower than 1.2 times the half-amplitude of the beam.

In this way, once the track pitch is lower than 1.2 of the half-amplitude of the beam, the first problem will be formed, that is, it will become very difficult to track and record the track.

This is not only the cutting of the recording track by laser, but also the magnetic separation between adjacent recording tracks by using the groove and the groove, because one of the groove and the groove needs to be used as a magnetic separation area, so also have the same problem

[0022] The second problem is that as the track density increases, because the recording tracks are close together, the adjacent tracks are erased during recording, resulting in so-called cross-talk erasure.

However, in practice, it is difficult to form a complete rectangular groove on the substrate of the optical disc.

Especially when deeper grooves are formed by injection molding, which is a commonly used method of forming plastic substrates, it is difficult to make the slope angle close to 90°

When the inclination angle is close to 90°, there will be problems such as that the disc is not easy to peel off from the disc manufacturing mold, and the production will be difficult.

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