New concept of a high efficiency photosensor with a reflective photocathode

A new concept of a HPD photosensor with high photon collection efficiency and high quantum efficiency is presented. The essential point of this new idea is that the highly sensitive but normally extremely expensive epitaxially grown negative-electron-affinity (NEA) photocathodes (like GaAs, GaAsP, InGaAs) may be used in a different configuration than usual, which will dramatically simplify the manufacturing process and reduce the cost. So far the major problem has been in the lack of a realistic conceptual photosensor design that would be able to simultaneously host the photocathode in a reflective configuration and to provide a flat angular acceptance with negligible dead area for the incoming photons. Our concept is based on a surprising invention that solves that problem in a very simple and elegant way, in reflective mode seems to be very promising