Optical disk

Abstract

Abstract PURPOSE:To prevent the disturbance of a tracking error signal in an ID part and to permit exact tracking control by setting the optical depth direction of the ID pit part and the guide groove for tracking control at the relative direction with respect to a disk reference plane. CONSTITUTION:Pits 10 of the ID part D are formed as projecting parts which project upward from the reference plane K of an optical disk LD. The optical depth direction of the pits 10 are set at the opposite direction with respect to the guide grooves E formed as recesses at lambda/8n with the reference plane K of the disk LD. The projecting height of the pits 10 is set at lambda/4n with respect to the reference plane K. The disturbance of the tracking error signal in the ID part D is thereby prevented with the simple structure and the exact tracking control is permitted.

Inventors

• 👤 Masami Emoto
• 👤 江本　正美
• 👤 Hideo Inuzuka
• 👤 犬塚　英雄

Bibliographic Details