Optical frequency comb generating device and optical pulse generating device using same, and optical frequency comb generating method and optical pulse generating method using same

An optical frequency comb generating device having a substrate having an electro-optical effect, a Mach-Zehnder type optical waveguide formed on the substrate, two optical modulation parts independently modulating optical waves propagating in two branch waveguides of the Mach-Zehnder type optical waveguide, and a phase regulator controlling a phase difference between the optical waves propagating in the two branch waveguides and in which a continuous light beam is input to the Mach-Zehnder type optical waveguide, RF signals are supplied to the two optical modulation parts, and an output light beam as an optical frequency comb is output from the Mach-Zehnder type waveguide, comprising:

• amplitude adjusting means for adjusting a voltage amplitude of an RF signal supplied to at least one of the optical modulation parts;
• monitoring means for monitoring the average intensity of the output light beam and outputting an output signal;
• and
• a bias control circuit that controls the amplitude adjusting means to change a difference in voltage amplitude between the RF signals supplied to each optical modulation part, that detects a variation of the output light beam corresponding to the variation of the difference in voltage amplitude from the output signal of the monitoring means, and that controls the phase regulator on the basis of the detection result to adjust the phase difference.