Optical disk apparatus, signal processing apparatus, and playback control method for optical disk apparatus

摘要

Signals (A, B, C, and D) obtained by reading information recorded on an optical disk are summed and amplified by an summing amplifier (N 1 ) to generate an RF signal. The RF signal is detected by a detection circuit (N 5 ) to obtain an off-track sate detection signal. If the off-track state detection signal repeatedly alternates between an off-track state and an on-track state, a duty detection unit (N 8 ) measures the duty of the off-track state detection signal. From the result, a sensitivity determining unit (N 9 ) determines the detection sensitivity of the off-track state detection signal in the detection circuit (N 5 ) and a detection sensitivity adjusting circuit (N 6 ) adjusts the detection sensitivity of the off-track state detection signal in the detection circuit (N 5 ).