| 摘要 |
PURPOSE:To record and reproduce data accurately and stably by detecting and holding the tracking error of a sector mark and performing recording and reproducing on a basis of this held error till detection of the next mark. CONSTITUTION:A sector mark SM is discriminated from the reflected light from a recording surface 10a by a circuit 18 to turn on a switch 22, and meanwhile, a circuit 20 detects the tracking error of the mark SM from the same reflected light, and a signal TER indicating this error is held in a circuit 24 through the switch 22. The tracking error of the mark SM is stored in the circuit 24 even after the mark SM passes a head 16 in accordance with rotation of a disc 10 and the switch 22 is turned off, and a tracking servo actuator 14 performs the control to hold the head 16 in a correct tracking position on a basis of the stored signal TER. |
