SHORT WAVELENGTH LIGHT SOURCE AND, OPTICAL RECORDING APPARATUS USING THE SAME

摘要

PROBLEM TO BE SOLVED: To obtain stable higher harmonics both at a continuous operation and at a modulation operation by setting a variation of an average output at the modulation operation with a short wavelength light source and a variation for the continuous operation within a specific value. SOLUTION: A wavelength variable DBR semiconductor laser is used at an SHG blue laser comprising an optical waveguide type wavelength conversion device and a semiconductor laser to make an average power at a modulation operation equal to a power at a continuous operation. Modulation is carried out to make an average output of the semiconductor laser constant, thereby setting a variation of the average output within 20%. Since the average outputs of the semiconductor laser as a fundamental harmonic at the continuous operation and modulation operation are made equal, a temperature of a semiconductor laser chip and an average carrier density in an active layer can be made constant and an oscillation wavelength of the wavelength variable DBR semiconductor laser can be maintained constant, whereby stable modulation characteristics for a blue light are realized.