A 4 X 4 Nonblocking Acoustooptic Waveguide Space Switch

Abstract

Optical space switch arrays and matrices in waveguide format constitute vitally important components in wideband multichannel fiber optic communication systems.(1) Most of the existing optical waveguide space switch matrices utilize electrooptic (EO) effects in LiNbO3 and may be cataloged into two types, namely, those utilizing parallel channel waveguide (directional-coupler) switches(2) in one and those utilizing intersecting channel waveguide (TIR-, X- or digital) switches(3) in the other. However, all switch matrices referred to above are configured in stages (or tandem), and require a large number of basic cross-point switches as the size of the switch matrix or the number of input and output ports increase. As a result, the real estate of the substrate and the optical propagation losses and crosstalks as well as the complexity in both electrode layouts and electronic driver circuits greatly increase with the size of the switch matrix. Furthermore, both the optical insertion loss and the crosstalks may vary widely with the route the light takes.