Modulation transfer function and efficiency of transparent luminescing materials

Transparent luminescing screens can be used as image transducers in radiographic and image-intensifier systems. The modulation transfer function (MTF) and efficiency of these screens when used in conjunction with a receiver or recording medium are obtained from the derivation of the point spread function of the screen–receiver system. The derivation accounts for all optical paths and attenuations of the luminescent energy producing the spread function. Both the theoretical MTF’s and energy-transducing efficiencies of several screen–receiver systems are presented for various system parameters. The MTF of an actual (ZnS) screen–film system, computed from this derivation, was found to be in excellent agreement with the MTF of the system determined by photographic photometry.