Patent ID: 7466639

Claim:
An optical disk device comprising: an optical pickup including a plurality of semiconductor lasers having different wavelengths, an objective lens, an actuator for moving said objective lens to cause it to approach or keep away from a recording surface of an optical disk, a spherical aberration corrector for correcting spherical aberrations of laser beams and photodetectors for detecting reflected rays from said optical disk; a drive circuit for actuating said semiconductor lasers and drive circuits for moving said actuator and said spherical aberration corrector, respectively; a signal processing circuit for generating signals from the reflected rays detected by said photodetectors; and a system controller for outputting a control signal to said drive circuit adapted to move said actuator so as to move aid objective lens in relation to said optical disk, outputting controls signals for activating said plurality of lasers of different wavelengths to said drive circuit and a control signal for controlling said spherical aberration corrector to said drive circuit and discriminating the kind of said optical disk from signals generated from said signal processing circuit, said spherical aberration corrector being operative to correct spherical aberrations in correspondence with respective ones of said plurality of semiconductor lasers.