EVALUATING METHOD OF OPTICAL PICKUP DEVICE, TEST DISK, AND OPTICAL DISK

摘要

PROBLEM TO BE SOLVED: To provide an evaluating method capable of smoothly evaluating separation performance (interlayer separation characteristics) of S-shaped curves in an optical pickup device and to provide a test disk used for the same.;SOLUTION: Time length B in a flat section of a focus error signal existing between an S-shaped curve S0 and an S-shaped curve S1 is determined and a separation degree of the S-shaped curves S0 and S1 is detected from a ratio B/A of the time length B to a time interval A between the S-shaped curves S0 and S1. When the ratio B/A is a threshold α or more, the interlayer separation characteristics of the optical pickup device are evaluated to be appropriate.;COPYRIGHT: (C)2009,JPO&INPIT