OPTICAL FREQUENCY SHIFTER AND ITS CONTROL METHOD

摘要

PROBLEM TO BE SOLVED: To obtain an optical frequency shifter which yields a large and desired amount of optical frequency shift. SOLUTION: A wavelength conversion apparatus 300A which consists of an optical coupler 303, a wavelength conversion device 304 and an optical filter 305 and another wavelength conversion apparatus 300B which consists of an optical coupler 307, a wavelength conversion device 308 and an optical filter 309 are connected in tandem. By multiplexing signal light 301 and control light 302 and supplying the resultant light to the wavelength conversion device 304, converted light is generated and outputted. This converted light constitutes the input light of a wavelength conversion apparatus 300B. When the input light (the converted light from the wavelength conversion apparatus 300A) and control light 306 are multiplexed and inputted into the wavelength conversion device 308, converted light is generated and outputted. The difference of the frequencies of the converted light outputted from the wavelength conversion apparatus 300B and input light 301 represents the frequency difference defined by the control light 302 and 306.