A comparison of the performance of different gamma-ray imaging systems

Many different gamma-ray imaging systems have been proposed for, or used in the nuclear radiation environment for the localization of radioisotopes. Examples include the simple scanning collimator, pinhole cameras, radon transform imagers and coded aperture imagers. In this paper we present the results of a series of Monte Carlo simulations aimed at quantifying the relative merits of these quite different imaging techniques. In particular the paper compares image quality with respect to angular resolution and sensitivity for a range of test scenes which includes both point-like and extended/structured sources. Whilst one technique may be preferred for technical reasons such as size or mass constraints, the comparison presented here provides a valuable insight into which imaging system is optimum for certain observation scenarios.