STUDY ON OPTICAL-PROPERTIES OF CERAMICS S CINTILLATOR FOR X-RAY CT EQUIPMENT .1. ANALYSIS ABOUT QUALITY RESPONSE CHARACTERISTIC

Demand for the improvement of the quality of X-ray CT detectors is inc reasing. In order to realize the requirement, Gd2O2S: Pr (Ce, F) scint illating powder was sintered using a HIP technique. The highest light output from a 1 mm thick specimen combined with a silicon photodiode, when excited by 120 kV X-rays, has reached 1.9 times of CdWO4 single c rystals. The CT equipment of the third generation type requires high u niformity among many scintillator elements. Particularly, quality resp onse characteristic and distribution of light output is very important . In this report, parameters which have a great influence on the quali ty response characteristic were studied using the Kubelka-Munk theory. Agreement between calculated and experimental results was obtained, a nd calculated results indicated that quality response characteristic i ncreased with increasing optical absorption coefficient, scattering co efficient and X-ray absorption factor.