Experimental Investigation of Free Space Optical Interconnects.

Abstract

Free space optical interconnects have applications in many optical systems such as crossbars, optical neural networks and telecommunications. The interconnect may be implemented in two ways; by the use of static holographic elements to fan out the input channels onto a modulating plane which allows only the only the appropriate channels to propagate1,2, or by using a dynamic holographic element to provide direct interconnection3,4. Ferroelectric, liquid crystal over silicon spatial light modulators (FLC/VLSI SLM’s) have been demonstrated to be suitable elements as both an amplitude modulating plane addressed by holographic elements, and as a phase modulating plane for encoding dynamic holograms. The aim of this paper is to assess the capabilities of FLC/VLSI SLM’s in both these roles using experimental test systems. In order to do this, performance criteria such as scalability, diffraction efficiency, uniformity, contrast ratio, optical throughput, and switching speed shall be considered. Finally, the analysis of these results will provide an insight into the performance of future FLC/VLSI SLM’s in optical free space routing systems.