Two fixed input optical fibers may be aligned with two movable output optical fibers. The two output fibers are moved by exchanging the positions so that either output fiber may be optically aligned with either input fiber. In another optical switch either one of two movable fibers may be optically aligned...http://www.google.fr/patents/US4896935?utm_source=gb-gplus-shareBrevet US4896935 - Fiber optic switch
