| 摘要 |
PURPOSE:To hold prescribed recording power and reproducing power by detecting a position of a movable part of an optical head and correcting plural laser beams in laser power in accordance with the position of the movable part. CONSTITUTION:An output signal from a position detecting mechanism 16 is processed by a movable part position detecting circuit 17 and outputted as an absolute position of a flexible part 2 in an information recording medium surface. In a laser power correcting circuit 18, a laser power setting value is corrected in accordance with the position of the movable part 2 in order to hold the prescribed recording power and reproducing power on the information recording medium surface against variations of laser power transmittivity of the individual laser beams. Based on this corrected value, the individual laser beams of a semiconductor laser 3 are driven by a semiconductor laser driving circuit 12. By this method, the individual laser beams can be held with the prescribed laser power on the information recording medium surface without depending on the position of the movable part 2. |
