A study on the reduction of exposure dose and contrast improvement by use of heavy elements filter

This work was on the reduction of exposure dose and contrast improvement by use of heavy elements filter. From the result of experimental evaluation, it was found that the beam harding of X-ray was not showed in Ho and Gd, heavy elements filters, contrast to Cu and Al filters in which the harding showed. And the ratio of transit dose to surface dose and the load of X-ray tube increase in order of Al, Cu, Gd and Ho, respectively. The contrast of X-ray images using the intensifying screen and the input phosphor showed the higher value in order of Cu, Al, Gd and Ho. Therefore, in the case of using contrast media and phosphor in region of diagnostic radiology, X-ray image quality depends primarily on kVp and heavy elements filters.=20