Multichannel acousto-optic crossbar switch

We analyze an acousto-optic crossbar switch architecture that can be used to implement an N x N point-to-point switch with just N hardware complexity. In our analysis, we determine that insertion loss and cross talk are minimized if we place the output ports in the diffraction far field of the acousto-optic cell. Using this result, we develop an optimum switch design based on Fourier optics: a Fourier transform lens is used both to scale the output beams for efficient coupling to the output ports and to provide a necessary optical fan-in from input to output ports. We demonstrate the performance of switch configurations using single-mode fiber input ports in conjunction with single-mode fiber, multimode fiber, and photodiode output ports.