Multiplexed Photopolymeric Holograms for Guided-Wave Optical Backplane Aimed at High Performance Computer Applications

The major bottleneck to upgrade the system performance of a high performance computer is primarily at the backplane level where interconnect distance seriously jeopardizes the data rate. Both material and device research works are needed to further enhance the data rate at the backplane level. Radiant Research, Inc. (RRI), proposes photopolymer-based multiplexed waveguide holograms for optical backplane interconnection scheme that is capable of providing the equivalent interconnectivity and the architecture flexibility promised by the three-dimensional optical interconnects while maintaining the packaging reliability, low system insertion loss and cost-effectiveness. The total aggregate bandwidth is expected to be two orders of magnitude higher than a single-channel optical interconnection and three orders of magnitude higher than that of electrical interconnection. The guided wave optical backplane employed is a ~mm thick waveguiding plate in conjunction with multiplexed volume holograms based on photopolymeric materials. Two-dimensionally ( 2D) pixelated signals can be bidirectionally transmitted and received using the third dimension. As a result, the highest interconnectivity can be realized while maintaining the TEMoo optical signal mode profile which significantly simplifies the system packaging. The system insertion loss is therefore greatly reduced. The idea presented herein is a truly bidirectional optical backplane bus with broadcast capability that is equivalent to EEE standardized bus protocols for VMEbus, Futurebus+ and FASTBUS. In phase I, the three-dimensionality of the proposed system will be demonstrated using a two dimensional (2-D) VCSEL array in conjunction with 2-D photopolymer-based waveguide holograms.