Abstract: A control system for reducing power used by an inductive lighting installation, usually plural fluorescent lamps and a ballast, includes an A.C. power input circuit to the installation with a signal-actuated, normally-closed primary switch in series in the circuit; a signal-actuated normally-open secondary switch is in shunt with the load. The two switches are actuated substantially simultaneously in each half-cycle of the A.C. power input, once for power reduction for a time interval T1-T2 and once for harmonic distortion reduction for a time T3-T4 that encompasses each A.C. power zero-crossing time TX. The control system has N different timing programs for times T1-T2 and T3-T4, each program corresponding to one type of ballast. In each program times T3 and T4 are constant; only the times T1 and T2 are varied for a series of successively greater power reductions; the maximum power reduction may be as much as 30 to 40 percent.

Abstract: An optical AND gate for use in a cross-bar arithmetic/logic unit including first and second optical substrates which are configured adjacent to one another with each of the optical substrates having a respective plurality of optical paths formed thereon. The pattern of optical paths form a plurality of intersecting regions where the optical paths associated with one of the optical substrates overlaps the optical paths associated with the other optical substrate. The optical substrates are operable for transmitting an incident light beam there through so as to produce an output at one of the intersecting regions. The optical substrates transmit the incident light beam only through the optical paths which have been illuminated by a plurality of light sources.

Abstract: An optical cross bar technique for logic and arithmetic operations utilizes crossed optical paths of light configured to define intersecting regions with each other corresponding to truth table or multi-level logic table inputs. The intensity of light at each intersecting region is discriminated to determine if two units of light intensity are present at each intersection, thereby indicating a particular logic state.

Abstract: A parallel optical arithmetic/logic unit has inputs from point-light sources forming a given spatial pattern corresponding to a given separation of point sources. The spatial pattern is presented to a multiplicity of channels by an optical system formed of linear optical elements. A static filter is provided in each channel which allows energy to pass when it comes from one spatial pattern but attenuates or diverts energy from all other spatial patterns. Thus, energy will emerge predominantly from only one channel for each specific spatial pattern separated by a given separation of point sources. The desired output state of each channel may be detected to indicate the results of an optical arithmetic or logic operation.