| 摘要 |
PROBLEM TO BE SOLVED: To provide the digital disk player capable of automatically discriminating whether a loaded disk is a single layer disk or a dual layer disk in a short time. SOLUTION: This DVD(digital video disk) player 1 is composed of an optical pickup 14, a focus error amplifier 18, a focus servo processor 20, a focus actuator driver 22, a focus zero-cross detecting part 24, a timer 26, a system controller 28 and an RF amplifier 40. An objective lens 14a is raised or lowered at a fixed speed, and when a focus zerocross signal corresponding to a signal recording surface of the 1st layer is outputted from a focus zero-cross detecting part 24, the timer 26 is started up. A mark signal for showing prescribed timing for likely obtaining a focus zero-cross signal corresponding to a signal recording surface of the 2nd layer is generated by the timer 26, and when the focus zero- cross signal in this timing is outputted, the disk 10 is judged to be the dual layer disk. |
