A novel scheme for optical pulse multiplication using fiber coupler loop-connecting configuration

Connecting an input port and an output port of a single-mode fiber coupler to form a fiber-loop, and making the time delay of the fiber-loop odd multiple of the half-period of the input optical pulse stream, we can obtain a pulse stream with multiplying repetition rate at the other output port of the coupler. Utilizing three loop-connecting fiber couplers cascaded, a pulse stream with eight times the repetition rate is achieved.