PARALLEL OPTOELECTRONIC INTERCONNECTIONS WITH HIGH PACKING DENSITY THROUGH A LIGHT-GUIDING PLATE USING GRATING COUPLERS AND FIELD LENSES

Optoelectronic interconnections between boards at 1 - 100 cm distances are proposed, which are based on a typically some 5-10 mm thick light -guiding plate for confinement and transport of the optical signals wi th low loss, on the order of 0.1 dB/cm. The plate is equipped with gra ting couplers fabricated as volume phase holograms in dichromated gela tin with insertion loss as low as 0.5 dB/coupler. The apertures of the optoelectronic transmitters are imaged onto the apertures of the rece ivers by aspheric field lenses or mirrors mounted on the plate. Such o ptical systems render packing densities as high as 1000 channel/cm2 po ssible that are required for the application of densely packed integra ted arrays of semiconductor lasers and detectors. Grating dispersion, axial astigmatism, geometrical distortion and coma are eliminated in t he proposed optical setup. Results from ray tracing and an experiment are presented.