Transputer-based image photon-counting detector

A prototype microprocessor-based electronic processing system is described which performs the on-line data processing in an image photon-counting detector. The detector head consists of a microchannel-plate intersifier optically coupled to a CCD with rapid-scanned readout. The digitized data are passed to a group of transputers which separate out the events, calculate the event centers to subpixel accuracy and accumulate the results in an image buffer. In the prototype, all processing is done in software for evaluation purposes. This paper discusses the basic design of the system, the centroiding algorithm and fixed patterning correction, and the implications of the results for future systems.