DETECTOR RESPONSE AND EXPOSURE CONTROL OF THE RADIO VISIOGRAPHY SYSTEM (RVG 32000 ZHR)

The RadioVisioGraphy system (RVG 32000 ZHR) was studied with respect to some physical properties including the precision and linearity of the exposure control and the detector response to x-rays. The x-ray unit was found to yield repetitive exposures that are precisely controlled by the CCX timer. A ''preheat'' and an ''after exposure'' period were noticed, and their resulting x-ray exposures were measured. Two RVG detectors were compared for their responses with x-rays. The differences between the detectors were insignificant. However, inhomogeneous detector responses were found in both of the detectors; with the same exposure, the central parts of the detectors yielded lower pixel values than the peripheral parts. A calibration equation was developed to correct for the inhomogeneity.