Statistical study of a gamma camera transfer function.

Abstract

In order to investigate the theoretical resolution of a gamma camera, the position transfer function of the input converters, scintillator and photocathode, has been studied. It is assumed that point scintillations occur in a scintillator at xy0 at a height h above a plane photocathode of sensitivity p per incident photon and that the spatial emission pattern of photoelectrons is known completely. A statistical analysis is given of various methods for determination of the estimator x0 of x0 both for a photocathode of finite and infinite extent. It is shown that the standard deviation sigma of this estimator x0 has a minimum value 2h/(N0p)1/2 where N0p/2 is the total number of photoelectrons emitted by the cathode.