An Investigation of the Parameters in Scintillation Camera Design

Abstract

A theoretical approach to the design of an optimum gamma camera system has been made by a mathematical formulation describing the operation of the system. The parameters considered as variables were the light guide thickness, the geometric array of photodetectors, the photocathode diameter, the phototube gain and the signal fractions inserted into the signal mixing network. Parameters which optimize the performance relative to transfer efficiency, image linearity and spatial resolution were determined. It was found that an optimum light guide thickness is approximately equal to one-half the tube separation distance (i.e. the radius of the detector phototube for the close-packed case). Peripheral tubes in the array must have increased gains relative to those in the centre. The optimum signal fractions agree well with those obtained by others using an empirical approach. The spatial resolution estimates are not widely different from those observed in systems already developed. This analysis indicates that the empirically developed systems now in routine use are near optimal and no dramatic improvements may be expected from further developments using presently available components.