管電圧指数と写真効果について

概要

論文の詳細を見る
The relation between the exponent of tube voltage and photographic effects has been studied by many experimenters both at home and abroad. In these experiments, however, the numerical value is apt to be different in every case, and most of the conditions remain unexplained. In order to throw light on this relation, the following experiments were devised. 1) Exponents of tube voltage were counted at every additional 60 kVp, under low voltage. 2) In order to gauge the thickness of object and filter, which are the factors of difference in the numerical value, the Al Keil phantom was used. 3) These experiments were based on the deristy gradient. From these experiments the following conclusions were obtained. 1) The exponent was not constant as tube voltage changed The difference in thickness of objects and filters made the exponent change a little. 2) A filter 0.5 mm.-1.0 mm, thick was considered to be the most suitable to decrease absorbed dose and to get good photographic effects. 3) The exponents counted in these experiments were put into the form of a diagram, which was used to take radiograms in a rational manner. This was found to be clinically useful.
1961-10-15