Free-space optical crossbar network integrated in a single block of LiNbO3 crystal

A free-space optical crossbar network integrated in a single block of LiNbO(3) crystal is proposed, which consists of stages of 2×2 switches making use of the electro-optic effect of crystal and in-between routing devices for permutation based on double refraction and internal double reflection on interfaces. Two basic configurations are suggested. A control algorithm for the crossbar network is discussed, which may control a nonblocking interconnection between any input and output. The integrated crossbar network is low energy loss, nonblocking, easy to assemble, and insensitive to environment. A 3×3 crossbar network is designed and the experiment is demonstrated.