| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical disk device which allows stable servo operation. SOLUTION: The device is provided with a recording signal processing section 7 which outputs recording signals to an optical disk 1, an optical head(object lens) 3 which irradiates the recording surface of the optical disk with a light beam, a laser control section 8 which controls the intensity of the light beam in response to the signal to be recorded, an arithmetic section 40 which calculates the value corresponding to the level of the signal to be recorded and an optical detector 4 which receives the reflected light from the optical disk to convert it into an electric signal. And the level of the output signal from the photodetector 4 are adjusted based on the gain calculated by the arithmetic section to control the position etc., of the optical head 3 in accordance with this adjusted signal. As the results, AGC is applied to each servo group of autofocus, tracking etc., in reference to the signal level to be recorded and the gain is thereby kept constant over the whole region of recording data. Accordingly stable servo operations are performed to allow reliable focus and tracking control. |
