Before the direction of inclination detecting optical memory and reproduction - disc device, and inclination detecting experience

摘要

PROBLEM TO BE SOLVED: To improve the quality of a light spot and recording and reproducing characteristics of a device by correcting the inclination of an optical disk to the optical axis of a light spot at respective radial positions of the inner periphery, the middle periphery and the outer periphery of the disk so that detected values of a tilt detecting means become proper values. ;SOLUTION: The tilt of an optical disk 101 is detected by comparing the amplitude of a front half part with that of a rear part or the level (upper envelope) of an upper side signal of reproduced signals being difference signal outputs of a bisected photodetector at the time staggered mark shaped continuous pits which are previously prepitted on the optical disk 101 are reproduced in a tracking-on state. The tilt is detected by using the difference signal between the signal from first shift pits and second shift pits while detecting the first shift pits and the second shift pits which are formed by being shifted to a first side direction and a second side direction from the track prodivided on the disk 101.;COPYRIGHT: (C)2000,JPO