OPTICAL DISK DRIVE, FOCUS OFFSET ADJUSTING METHOD

摘要

PROBLEM TO BE SOLVED: To precisely adjust the focusing to the optimum point in a simple configuration by using a reproduction function of a PRML system. SOLUTION: In the optical disk drive, the signals from the optical pickup head 11 are input to the signal processor 14 through an RF amplifier 13 and an A/D computer. The signal processor 14 processes the signals input in an equalizer error producing circuit by using an PRML (Partial Response and Maximum Likelihood) system and produces equalizer error signals from those signals to output to the controller 18. The controller 18 sets up the focus offsets to use for focusing in the optical pickup head 11 based on the equalizer errors output from the signal processor 14. COPYRIGHT: (C)2007,JPO&INPIT