Abstract

The nonlinear optical loop mirror is a fiber-based Sagnac interferometer. The device can be made from standard communications fiber and couplers and is extremely stable. The most useful version, for all-optical switching, is the two- wavelength loop mirror as illustrated in Fig. 1. The loop coupler is a 50:50 splitter and can be made to be broadband. The two couplers inside the loop couple the optical switch in and out of the loop. This arrangement achieves two functions; it effectively separates the optical circuits of the switch and signal beams and it makes the switch power available for re-use.

© 1992 Optical Society of America