Preliminary study on an imaging system with a two-dimensional photodetector and a thermoluminescent plate

Currently, two dimensional photodetectors such as cooled CCDs are available. Although they suffer from their small sizes, they can take an optical image within a short time. To overcome the size restriction, we plan to use a memory-effect as is used in FCR. Multiple TL (thermoluminescence) plates are used to take a radiation image, and afterwards the TL plates are heated to obtain a visible light image. This configuration will realize both a fast time response and a large sensitive area. After a series of experiments, we have obtained TL images using a cooled CCD with ZnS, CsI, Gd/sub 2/O/sub 2/S phosphors at low temperatures down to liquid nitrogen temperature. These first results were encouraging ones both for the response time and the image quality.