The Photicon

We report on the performance of a new type of imaging optical detector which we call the Photicon. It uses a conventional semitransparent photocathode, imaging electrostatic optics, microchannel plates, and a crossed wire grid position-sensitive charge detector. Single photon events produce a digital word giving the position of the event. An image can be accumulated in a memory array, or stored serially with each event’s time of occurrence recorded with 10−6-sec precision. Spatial resolution of σ≃20 μm has been achieved so far in a 25-mm-diam active area detector.