Abstract
In supervoltage x-ray it is well known that the dose beneath the skin surface depends upon the build-up effect of x-ray. The purpose of this paper was to discuss whether the build-up effect gave some influences to the effect intensifying screens or not, for the diagostic linacgraphy. Three kinds of intensifying screens were used GS-Kyokko, RS and Gd-Toshiba. And in each case it was discussed whether the Pb-foil should be used or not. (it's thickness 0.1 or 0.3mm) When the intensifying screen was used the contrast of the film was good but the sharpness was unsatisfactory without the Pb-foil.
