A three-dimensional (3-D) substrate-guided-wave to free-space multistage optoelectronic interconnection using wavelength division multiplexing and space division demultiplexing

An integrated 3-D guided-free-space four-stage optoelectronic fan-out (6×6, 2×6, 6×6: and 2×6) interconnect using wavelength division multiplexing (WDM) is proposed and then demonstrated together with 40 (2×4×5) 3-D optoelectronic fan-outs using space division demultiplexing (SDDM). This channel separation is one order of magnitude smaller than that using wavelength-selective detecting techniques in WDM. A signal to noise ratio of 57 dB is experimentally determined, with two channel 40 (2×4×5) fan-outs having a channel separation of 600 μm in SDDM. The interconnection scheme presented herein allows each pixel in a transmitting plane to communicate simultaneously and reconfigurably with many pixels in the subsequent planes in a truly 3-D feature. This system can utilize vertical cavity surface emitting laser diodes, photo detecting planes, and planar compact guided-free-space fan-out interconnects, allowing compact multistage integration. By using 2-D spatially separated or multiplexed hologram arrays on a thin light guiding plate, the interconnection capability is greatly enhanced as compared to other techniques. This novel optoelectronic interconnect technology may have widespread applications in microelectronic systems and fiber-optic communication networks