A compact and scalable free-space optical crossbar

The authors have introduced the design for a compact and scalable free-space optical crossbar. A 256 channel system switching from monomode fibres to multimode fibres which can operate at up to 1 Gbit/s per channel should be realisable using currently available technology. This scheme operates by the use of a diffractive fanout element to multiply image an array of Gaussian beamlets onto a reflective electrically addressed liquid crystal spatial light modulator. This scheme demonstrates an excellent application for computer generated fanout holograms. Experimental investigations have demonstrated that crosstalk between adjacent channels is greatly reduced by the use of Gaussian beamlets.<>