Electron-Image Recording by Xerography

Abstract

THE electrophotographic process of xerography¹, initially described for the recording of optical images, has since received a considerable amount of attention with regard to its application in medical and industrial radiography^2,3. The mechanism of image formation depends, primarily, on photoconductivity produced in a film of a black vitreous form of selenium by the incident radiation. To date, xerography has been used satisfactorily for recording images formed by visible light, ultra-violet radiation and X-rays. The observation, by Pensak, of induced conductivity in a thin film of amorphous selenium during electron bombardment⁴ suggested the possible application of xerography to the recording of electron images of the type produced in electron microscopes and electron diffraction cameras. During the course of an electron diffraction investigation of the structure of evaporated selenium films, some preliminary experiments of this kind have been carried out.