METHOD AND DEVICE FOR CONTROLLING LASER POWER OF SEMICONDUCTOR LASER, METHOD AND DEVICE FOR RECORDING/ REGENERATING WITH PHOTOMAGNETIC RECORDING MEDIUM, AND METHOD AND DEVICE FOR RECORDING/REGENERATING WITH OPTICAL RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide a driving method for a semiconductor laser in which the power consumption of an output transistor is reduced. SOLUTION: The series circuit of an output transistor Qb and a semiconductor laser SL is applied with a variable power-source voltage Vcc which is controlled so that a difference between the variable power-source voltage Vcc and the peak hold voltage of the operation voltage of the semiconductor laser SL is almost constant.