image contrast in image intensifier TV system refers to the placement of a circular lead plate equal to 10% of the effective area of the input screen in the center of the enhancement tube. The maximum brightness of the lead-free part and the brightness of the lead-shielded part are observed from the output screen. The ratio of the two is called image contrast. Because the output screen of image intensifier tube has background gray level, its image contrast is lower than that of general fluorescent screen. The image contrast in image intensifier TV system is the image quality of image intensifier. It directly affects the observation image of display screen. Good image contrast can be more conducive to doctors’observation and detection of lesions.
Therefore, the image contrast in image intensifier TV system is an important part of the technical parameters of image intensifier.