An optical backplane for propagating a light beam

An optical backplane 1 is provided that has at least first and second side walls 12, 13 that are generally parallel to one another and at least one optical relay element 20 disposed on at least one of the parallel side walls 12, 13. An optical signal coupled into the optical backplane 1 through an entrance facet 11 of the backplane. The optical signal is maintained within the optical backplane 1 by internal reflection at the parallel side walls 12, 13 of the backplane. The optic relay element 20 receives the optical signal reflected off of one of the side walls 12, 13 and reflects and refocuses the optical signal to guide the optical signal and prevent it from diverging as it propagates through the backplane 1 from the entrance facet to the exit facet 21.