An In-Line Optical Bandpass Filter with Fiber Gratings and an Optical Circulator and Its Application to Pulse Compression

Abstract

In-line optical bandpass filters having sharp spectral edges are demonstrated for the first time by combining an optical circulator and fiber gratings. The maximum transmission including the optical circulator is 65%. A spectral windowing technique using the filter enabled a picosecond pulse from a gain-switched DFB LD to be shortened from 35 ps to 28 ps.