Digital optical computers can be built from waveguide switches and optical fiber. We describe the approach, research drivers, applications, and initial results of a program to build an all-optical, stored program computer in this way.
Harry F. Jordan,
"Fiber optic computer architectures", Proc. SPIE 10257, Digital Optical Computing: A Critical Review, 102570F (16 January 1990); doi: 10.1117/12.2283579; https://doi.org/10.1117/12.2283579