Xeroradiography applied to the inspection of electrical equipment

Xeroradiography is a new method of radiography which utilizes the photoconductivity of amorphous selenium when exposed to X-rays or ¿-rays. A visible powder image is produced on a thin selenium layer deposited on a supporting metal plate. The plate can be used repeatedly. Development of a visible image after exposure requires only 6¿10 sec. The image has a high contrast for sharp changes in the thickness, or X-ray absorption, of the object being inspected, but for a gradual change in X-ray intensity the contrast is very low. These two features enable a sample with a wide thickness range to be examined with one exposure and simultaneously a high contrast of image details can be obtained. In comparison with conventional film radiography, details are more easily seen and viewing is less fatiguing owing to the smaller brightness range of the image. The paper includes xeroradiographs of a number of electrical components and materials used in the electrical industry.