Optical modulator.

摘要

In an optical modulator provided with a laser light source emitting a laser light, that is to be modulated by an optical modulator, the laser light source is made a wavelength variable laser that emits a laser light the wavelength of which is variable, and there are provided modulation signal means for applying a modulation signal to the optical modulator, signal producing means for producing and outputting a signal in response to the change of the voltage of the modulation signal, driving current generating means for generating a driving current to be applied to the laser light source. By the output signal of the signal producing means, a wavelength chirping reverse to the wavelength chirping occurring in the optical modulator is given to the laser light that is emitted from the laser light source caused by that the driving current for the laser light source varies in response to the change in the modulation signal, whereby the wavelength chirping occurring in the optical modulator is canceled, and the wavelength chirping of the modulation signal light that is emitted from the optical modulator is reduced.