OPTICAL CLOCK SIGNAL EXTRACTION CIRCUIT

摘要

PROBLEM TO BE SOLVED: To extract a clock signal from the light signal of very high speed without depending on a polarized wave and with simple constitution. SOLUTION: A first means 1-1 outputting an optical frequency distribution signal obtained by Fourier-transforming an intensity modulation RZ light signal on a time space and developing it on a real space, a second means 2 inputting the light frequency distribution signal and filtering only an optical frequency distribution component on the real space, which corresponds to the clock frequency of the intensity modulation RZ light signal and a third means 1-2 outputting a light clock signal obtained by Fourier-transforming the optical frequency distribution component and reproducing it on the time space are included. A space filter or an array waveguide is used for the second means 2.