Design considerations for efficient binary megavoltage photon detector structures

In this work, Monte Carlo methods are used for the design of highly-efficient detector structures for megavoltage X-ray imaging. The detector structures consist of a converter material and an active medium ("binary" detector systems). The novel approach is to impose a spatial structure on the converter material which intersperses the active medium and defines a specified cell size. The dimensions of these structures have to be optimized with respect to efficiency and spatial resolution. The results show, that the efficiency (quantum efficiency and detective quantum efficiency at zero frequency) of such structures surpasses the efficiency of currently available detector technologies by far. The efficiency depends on the dimensions of the converter structure and the active medium as well as the materials itself. In general, larger converter structures result in a higher efficiency. However, the size of the structures are limited by the specifications for the desired spatial resolution.