Optical disk drive unit, and an optical disk reproducing method using the same

In the optical disc drive apparatus according to the present invention (100), motor (2) rotates the optical disc (1) at a desired rotational speed. An optical pickup (3) is irradiated with a laser beam (5) from the built-in semiconductor laser (4) to the optical disc (1), to obtain an optical disk reproduced signal from the laser beam reflected by the (1) (7). Laser drive unit (8) driving current of the semiconductor laser (4) to (9) is controlled to a desired level, it superimposes the desired level of the high frequency current (11) to the drive current (9). Controller (12) is in the high-speed reproduction mode, the rotational speed of the optical disk (1) is set higher than the rotational speed in the normal reproduction mode, normal reproduction power of the laser beam irradiated to the optical disc (1) (5) set high than the power in the mode is set lower than the level of the level of the high frequency current (11) in the normal reproduction mode.