公开(公告)号：JPH02276024A

公开(公告)日：1990-11-09

申请号：JP8369389

申请日：1989-03-31

Applicant: SONY CORP

Inventor： OGAWA HIROSHI ,  KATSURAMOTO SHINJI ,  YAMAMOTO MASANOBU

IPC: G11B7/00 ,  G11B7/004 ,  G11B7/005 ,  G11B7/09 ,  G11B7/125

Abstract: PURPOSE:To suitably control 9 recording laser beam by forming an error signal in focusing, tracking, etc., of the recording laser beam based on the detecting output of returned laser beam intensity in a time range necessary until pits are practically formed on a recording medium. CONSTITUTION:In the prescribed time range necessary until the pits are practically formed on an optical disk 1 by the laser beam outputted when an optical head 20 is in a recording mode, a detecting output by a photodetector 22 is sampled. Further based on a detecting output voltage, the laser beam focus error signal and the tracking error signal are formed, a head servo control operation is executed. Thus the head servo control operation can be suitably executed without being affected by the pits formed on the optical disk 1.