Abstract: A light emitting unit is caused to emit a laser beam having a pulse width T1 broader than a pulse width T2 used at a time of recording, and a light receiving unit is caused to receive the laser beam and to output a first detection signal. A first control signal V1 is generated by comparing a value held at a peak level of the first detection signal with a target value of a quantity of the laser beam, and a second control signal V2 is generated by comparing the first control detection signal with the target value of a quantity of the laser beam.

Abstract: An optical disc apparatus has a disc motor which rotates an optical disc, a pickup which has a laser element driven by a drive current and irradiates the optical disc with a laser beam, a plurality of signal lines which transfers control information of the drive current to the pickup, and a drive control circuit which serially transfers the control signal to the pickup using at least one of the plurality of signal lines.

Abstract: A light emitting unit is caused to emit a laser beam having a pulse width T1 broader than a pulse width T2 used at a time of recording, and a light receiving unit is caused to receive the laser beam and to output a first detection signal. A first control signal V1 is generated by comparing a value held at a peak level of the first detection signal with a target value of a quantity of the laser beam, and a second control signal V2 is generated by comparing the first control detection signal with the target value of a quantity of the laser beam.