A recognized model for an all-optical digital computer consists of arrays of optical logic devices interconnected in free space with bulk optical components. A problem with this approach is that device arrays must be spaced to allow for components placed between them such as lenses, gratings, and beam splitters. The latency introduced by this spacing may be greater than device switching times, which means that tight loop processing of digital information is not possible. A solution to this problem is to replace large optical components with monolithically fabricated devices, lenses, mirrors, beam splitters, and combiners. Some connection freedom is lost due to practical limits on configurations of small components. These limits and a method to minimize their effects are explored here. It is concluded that log2N optical interconnects such as perfect shuffles and crossovers are not necessary for efficient digital architectures and that simple split, shift, and combine operations may be preferred for simpler optical implementations.
© 1990 Optical Society of America
Miles Murdocca, "Connection routing for microoptic systems," Appl. Opt. 29, 1106-1110 (1990)