LASER MODULATION WAVE ADJUSTING DEVICE

PROBLEM TO BE SOLVED: To surely and readily adjust the amplitude change and/or the frequency change of a low frequency signal superposed on a laser beam. SOLUTION: In this laser modulation wave adjusting device, light monitored from an LD1 is branched, one branched light is received by a PD 13 and the other branched light is received by a PD 14 by carrying out filtering by an optical filter 12, the wavelength lock control of a laser beam outputted by the LD1 is carried out based on values of light received by the PDs 13, 14, and a low frequency signal f is superposed on the laser beam and outputted. The adjusting device is provided with a comparator 5 which obtains the amplitude displacement and/or frequency displacement of a laser beam generated by the low frequency signal f superposed on the laser beam based on the values of light received by the PDs 13, 14, and a low frequency control circuit 6 which adjusts the amplitude displacement and/or the frequency displacement of the laser beam generated by the low frequency signal f based on the amplitude displacement and/or the frequency displacement. COPYRIGHT: (C)2005,JPO&NCIPI