An energy dispersive x-ray and gamma-ray photon counter is described. The counter uses a photon sensor which incorporates a unique photocathode called Advanced Semiconductor Emitter Technology for X-rays (ASET-X) as its critical element for converting the detected photons to electrons which are emitted...http://www.google.es/patents/US6201257?utm_source=gb-gplus-sharePatente US6201257 - Semiconductor X-ray photocathodes devices
