Patent ID: 6449232
Filing Date: 2002-09-10
Classification: G11B

Abstract:
A method for determining the type of a disk, including:a first step of determining a substrate thickness of the disk based on a focusing error signal representing a positional deviation of the focal point of a light beam from a recording surface of the disk, when a focusing section is moved in such a way as to approach or withdraw from the recording surface of the disk, the focusing section including a plurality of focusing characteristics for bringing the light beam into a focus on the disk; a second step of determining the number of recording surfaces of the disk using a focusing error signal when the focusing section is moved in such a way as to approach or withdraw from the recording surface of the disk; and a third step of determining whether or not the disk can be recorded and reproduced using a tracking error signal representing a positional deviation of the focal point of a light beam from a track of the disk, when the light beam crosses the track, wherein after the first step is performed, the second stop and the third step are performed in the descending order or in the ascending order while the focusing characteristics of the focusing section are switched in accordance with the substrate thickness of the disk determined by the first step.