A light source for testing radiological television cameras.

Abstract

A light source for testing and setting up radiological television systems has been designed and built using green light emitting diodes and an optical integrating sphere. It is shown to have an optical spectrum similar to the green output phosphors used in x-ray image intensifiers (XRII's). It can be made uniform in intensity across the output port and does not show the small scale granularity characteristic of phosphors. It has a Lambertian angular distribution which, by the addition of neutral density filters, can be made to mimic the angular distribution at the output of an XRII. It can easily and accurately be modulated or switched and a luminance comparable to that of an XRII output phosphor can be achieved.