Ion Source Control through High Voltage Isolation Distances Utilizing Photon-Coupled Solid State Devices

Semiconductor luminescence is being used to control a pulsed ion source operating at a high potential isolated from ground. Various methods of photon-coupling may be used such as optical focusing with lenses or mirrors or by guiding the light beam through an optical fiber bundle. The latter method is presently being used in a system designed in collaboration with Dr. C. D. Curtis of NAL. The isolation distance for this ion source test bench will stand off 150 kV. Operation of the source at this distance has been satisfactory. Preliminary tests indicate that the isolation distance may be increased to a distance capable of standing off as much as a megavolt. Among the advantages of a system such as described in this paper are simplicity of electronic circuitry, lack of complicated optical focusing, many channels for information or control may be placed in a small space, and the optical bundles need not be placed in a straight line.