title: A comparative evaluation of rare-earth screen-film systems. System speed, contrast, sensitometry, RMS noise, square-wave response function, and contrast-dose-detail analysis.
abstract: We evaluated the physical characteristics and contrast-dose-detail performance of 11 rare-earth and three calcium tungstate screen-film systems. Measurements included system speed, contrast, sensitometry, RMS noise, square-wave response function, and contrast-dose-detail analysis. The major differences in physical characteristics among systems were system speed and RMS noise. Square-wave response differences were more subtle. For contrast-dose-detail analysis, the rare-earth screen-film systems and the calcium tungstate system responses were significant over a limited subject contrast range as a function of detail diameter. Relative dose efficiency in the noise-limited region is a function of the properties of the screen only and is independent of the film.
mesh_terms: D017610:Calcium Compounds; D008674:Metals, Rare Earth; D008961:Models, Structural; D011856:Radiographic Image Enhancement / Q000295:instrumentation*; D011858:Radiographic Magnification / Q000295:instrumentation* / Q000592:standards; D014414:Tungsten; D017973:Tungsten Compounds; D014962:X-Ray Film; D014963:X-Ray Intensifying Screens / Q000592:standards*
chemical_list: D017610:Calcium Compounds; D008674:Metals, Rare Earth; D017973:Tungsten Compounds; C018858:calcium tungstate; D014414:Tungsten