An all-fiber interleaver with different output spectrum bandwidths based on M-Z interferometer(MZI) using two 3×3 and a 3×3 fiber couplers with almost rectangular wavelength response is developed by using a new configuration.The results indicate that when the length differences of interference arms are the same and the coupling coefficients of the couplers are some certain values, the device splits a input beam with channel spacing of 50 GHz into two beams for odd channels at 10 Gb/s and for eve...