Patent ID: 9746699
Date: 2017-08-29
CPC Classifications: G02B,G02F,H04B,H04J

Claim:
1. An optical frequency shifter comprising: a splitter configured to branch a first optical signal having a first frequency component; a first mutual phase modulator configured to generate a second optical signal having a second frequency component and a third optical signal having a third frequency component with mutual phase modulation of the first optical signal and a first optical beat signal having a desired frequency interval; a first phase converter configured to change a phase of an output of the first mutual phase modulator so as to be different from the second optical signal and the third optical signal; a second mutual phase modulator configured to generate the second optical signal and the third optical signal with mutual phase modulation of an output signal of the first phase converter and a second optical beat signal having a desired frequency interval; and a combiner configured to interfere between an output of the second mutual phase modulator and another optical signal obtained by branching of the splitter.