RADIOGRAPHIC IMAGING SYSTEM OF THE RARE EARTH SCREEN-FILM COMBINATION : PROPERTIES OF RARE EARTH PHOSPHOR AND THE IMAGE QUALITY OF THE RARE EARTH SCREEN-FILM COMBINATION

Abstract

Recently, the rare earth screen-film combination attracts attention because of decreasing the radiation dose to the patient. To improve the image quality of this combination, we recognized the fundamental properties of the rare earth phosphor fully. Further we considered the factors required to decrease the exposure and to improve the image quality. We considered physically the effective methods of using the rare earth screen-film combination. We considered the following. 1) The process of using hi-speed systems and the status quo. 2) The properties of the rare earth screen. 3) The factors of the image quality in the hi-speed range. 4) The image quality of the rare earth screen-film combination. To use this rare earth screen-film combination effectively in radiographic diagnoses, it is important that we improve the image quality by using the small focus and radiographing for a short exposure time. Particularly it is effective to apply this combination to gastrointestinal radiography, angiography and magnification technique. In future it will be effective to apply to mammography and multitomography.