GUIDED-WAVE PLANAR OPTICAL INTERCONNECTS USING HIGHLY MULTIPLEXED POLYMER WAVE-GUIDE HOLOGRAMS

A new intraplanar interconnection scheme using substrate guided modes in conjunction with a highly multiplexed waveguide volume hologram is presented. 1-to-50 passive and 1-to-2-to-100 acoustooptically addressed reconfigurable interconnections were demonstrated with a fan-out diffraction efficiency of 55% at 514-nm wavelength. A coordinate transformation converts the three-dimensional (3-D) diffraction problem into a two-dimensional (2-D) one which significantly simplifies the theoretical calculation. Intraplane massive fan-out optical interconnection using substrate guided mode provides us with both collinear and coplanar fan-out capability for data and clock signals. Collinearity of signal distribution allows us to process the 2-D input signal array which is not achievable using conventional single-mode integrated optical devices. The applicability of the reported concept can be transferred to any substrate of interest, such as GaAs and Si, as long as the transparency of the substrate holds. The laminated waveguide device containing a highly multiplexed dichromated gelatin (DCG) hologram was evaluated. It demonstrated an outstanding survivability in harsh environments, including low and high temperature (-100 to +180-degrees-C), water immersion, laser damage threshold (10 kJ/cm2), and nuclear radiation hardening (under 63-Mev proton >2 Mrad (Si), and Co-60 Gamma Ray >2 Mrad (Si) without loss of diffraction efficiency). Finally, we present the most attractive applications, including intrawafer clock signal distribution, backplane optical interconnection, surface enhanced Raman scattering (SERS) sensor, head-up displays, and module-to-module optical interconnection.