Patent ID: 8462599
Filing Date: 2013-06-11
Classification: B82Y,G11B,H01S

Abstract:
1. A recording apparatus comprising: a self-excited oscillation semiconductor laser that has a double quantum well separate confinement heterostructure and includes a saturable absorber section to which a negative bias voltage is applied and a gain section into which a gain current is injected; an optical separation unit that separates an oscillated light beam from the self-excited oscillation semiconductor laser into two oscillated light beams; an objective lens that condenses one of the separated oscillated light beams on an optical recording medium; a light reception element that receives the one of the oscillated light beams separated by the optical separation unit; a pulse detection unit that detects a pulse of the oscillated light beam received by the light reception element; a reference signal generation unit that generates a master clock signal; a phase comparison unit that calculates a phase difference between the master clock signal and the pulse; a recording signal generation unit that generates a recording signal using a negative voltage at a timing of the master clock signal; and a control unit that controls the negative bias voltage to be applied to the saturable absorber section based on the recording signal and that outputs a direct current voltage during a non-oscillation period of the self-excited oscillation semiconductor laser and outputs a period voltage changed at a desired period during an oscillation period of the self-excited oscillation semiconductor laser; wherein the control unit controls the gain current to be injected into the gain section of the self-excited oscillation semiconductor laser based on the phase difference and adjusts an interval of the pulse during the oscillation period.