Design and implementation of an electro-optical backplane with pluggable in-plane connectors

Abstract

The design, implementation and characterisation of an electro-optical backplane and an active pluggable optical connector technology are presented. The connection architecture adopted allows line cards to mate and unmate from a passive electro-optical backplane with embedded polymeric waveguides. The active connectors incorporate photonics interfaces operating at 850 nm and a mechanism to passively align the interface to the embedded optical waveguides. A demonstration platform has been constructed to assess the viability of embedded electro-optical backplane technology in dense data storage systems. The electro-optical backplane is comprised of both copper layers and one polymeric optical layer, whereon waveguides have been patterned by a direct laser writing scheme. The optical waveguide design includes arrayed multimode waveguides with a pitch of 250 μm, multiple cascaded waveguide bends, non-orthogonal crossovers and in-plane connector interfaces. In addition, a novel passive alignment method has been employed to simplify high precision assembly of the optical receptacles on the backplane. The in-plane connector interface is based on a two lens free space coupling solution, which reduces susceptibility to contamination. The loss profiles of the complex optical waveguide layout has been characterised and successful transfer of 10.3 Gb/s data along multiple waveguides in the electro-optical backplane demonstrated. © 2010 Copyright SPIE - The International Society for Optical Engineering.