Secondary electron conduction vidicon tube for low level gamma ray imaging

A type of imaging tube for X-rays and gamma rays in the 80 KeV and higher energy range was described. The tube had the ability to image low flux levels of incident radiation by the process of charge integration in the target plate while the reading electron beam was turned off. Charge integration for long periods was accomplished by attaining a very high resistivity for the target plate. The main design effort centered around the processing of the target plate. The technique of obtaining maximum signal current for a given radiation energy was one of optimizing the photoelectric and the accompanying secondary electron emission from the lead and alkali halide layers.