Prototype position-coded residue look-up table using laser diodes

A prototype residue-arithmetic, position-coded, look-up table has been fabricated using laser diodes. It utilizes a 7x7 array of discrete laser diodes which are driven via an interlaced electrode grid. Optical addition takes place through the use of fiber-optic, resilient-ferrule connectors. Experimental results show that operation exceeding 250 MHz (RZ data) or 500 MHz (NRZ data) is possible with low cross-talk. Current pulse reflections represent a potentially major problem.