Abstract: A scintillation camera has a planar scintillating crystal that produces light events whose spatial distribution corresponds to the spatial distribution of the radiation stimuli causing such events, and a plurality of photomultipliers having photocathodes for receiving light from the crystal through a planar face thereof. Computing circuitry coupled to the photomultipliers computes the projection of a light event in the crystal on a reference axis by forming an analytical function of the outputs of the photomultipliers according to the spatial location of the light event in the crystal.

Abstract: A head for a scintillation camera has a planar scintillating crystal that responds to radiation stimuli by producing light events whose spatial distribution corresponds to the spatial distribution of the radiation stimuli, and a plurality of photomultipliers each having a photocathode facing the crystal and producing an output signal when a light event occurs. The photomultipliers are organized into a first group arranged in a cluster centrally positioned relative to the crystal and having smaller photocathodes than those in the second group which is arranged in an annular array surrounding the first group. The head of the camera is connected to signal processing circuitry for computing each of two spatial coordinates of a light event by forming analytical functions of the output signals. Such circuitry has two selective modes of operation.