Camera tube selenium target including arsenic increasing in concentration from radiation side

摘要

A camera tube having an electron source and a target to be scanned on one side by an electron beam emanating from said source. Radiation forming the image to be detected is incident on the other side of the target. The target comprises a signal electrode and a selenium-containing vitreous layer containing arsenic. The arsenic concentration in the selenium-containing layer increases continuously from the radiation-receiving side of the layer to the side which is scanned by the electron beam. The signal electrode is on the radiation-receiving side of the layer and thus on the radiation-receiving side of the target.