Recording disk

Abstract

Abstract PURPOSE:To realize the recording with a constant linear speed and to increase the recording density of an information signal, by forming a pregroup of a recording disk with unit pregroup of a prescribed length to use it as the linear speed information. CONSTITUTION:The unit pregroups 2a, 2b, 2c... of a prescribed lenght, i.e., the spiral grooves plus non-groove parts of a prescribed length provided between the pregroups are set previously at the positions corresponding to the recording part on a disk substrate 1a. Then a recording layer 1b is coated on the substrate 1a. When the information signal is recorded on such disk 1, the tracking is secured via a pregroup 2. At the same time, the speed of revolution of the disk 1 is controlled so that the time corresponding to the laser beam is constant for each unit pregroup. In such a way, the recording is possible with a constant linear speed and the recording density is increased for the information signal.

Inventors

• 👤 Masahiko Sato
• 👤 政彦 佐藤

Bibliographic Details