| Wavelength division multiplexing and demultiplexing (WDDM) are considered key technologies to enhance the fiber optic transmission bandwidth. Optical communication systems based on WDDM technologies not only provide high speed data paths, but also provide the convenience of channel independence and data format transparency. I have designed and fabricated the first multi-mode WDDM based on axial graded index (AGRIN) lenses in conjunction with substrate-guided waves and a volume holographic grating. The diffraction-limited AGRIN lenses employed significantly increase the output coupling efficiency and reduce crosstalk when compared with the best homogeneous lens solutions previously reported. An active packaging strategy is effectively implemented and verified.; In high performance multi-chip-modules (MCMs), local area networks (LANs) and massive parallel processors (MPPs), connections among different chip elements are critical. Since for a massive parallel high performance computing, both the internal clock rate of the processor and the connection speed determine the system performance. Self-routing and non-blocking crossbar switches are ideal for such applications. Electronic switches, though easy to construct, are susceptible to RC delay. With increasing transmission rate and distance, the large resistance and capacitance will eventually limit the system speed to the connection speed. Building non-blocking and self-routing crossbar switches with optics is a natural choice for high performance parallel processing systems. Crossbar-based optical interconnection represents the most desirable network switching configuration due to its fast switching speed and low latency in transmitting high speed signals. In this dissertation, I present two types surface-normal non-blocking all optical crossbar interconnect based on surface-normal holograms. A prototype polymer-based 4 x 4 crossbar is experimentally demonstrated at 750, 780, 810 and 840 nm. The unique wavelength demultiplexing and beam routing properties of the volume holograms, in combination with the WDDM, reduce the required sixteen wavelengths to four wavelengths while maintaining the required sixteen (4 x 4) individual interconnects. Furthermore, the elimination of edge coupling significantly enhances the packaging reliability. |
