Abstract
Under the most suitable photographic conditions to the mediastinum density in angiocardiography (abbriviated as A.C.G. herein-after), the density to the lung is over-much and the photographic discernment of the pulmonary artery and vein decreases much less in the periphery. If the photographic density to such part of human body that has much difference of X-ray absorptivity could be compensated, therefore, the ability of diagnostication would increase more and more. With this purpose, we designed a density compensation filter for A.C.G and obtained good results. Moreover, the examinees had much less exposed quantity of X-ray. We report about these here in this paper.
