In this paper we present the design for an optical switching system for minicomputers that uses an optical spatial light modulator such as a Hughes liquid crystal light valve. The switching system is designed to connect 80 minicomputers coupled to the switching system by optical fibers. The system has two major parts: the connection system that connects the data lines by which the computers communicate via a two-dimensional optical matrix array and the control system that controls which computers are connected. We first present the basic system, then describe the matrix-based connecting system and review some of the optical components to be used. Finally, the details of the control system are given and illustrated with a discussion of timing.