Original Publication Date: 1976-Mar-31
Included in the Prior Art Database: 2004-Mar-27
Xerox Disclosure Journal
Disclosed is a method for forming an electrostatic latent image by exploiting the phenomenon of interal photo- emission, In one embodiment of this method, a metal (or other suitable photoemitting surface) is placed in contact with a transparent dielectric layer which in turn is backed by a transparent electrode (such as a piece of NES.~glass) The metal is illuminated through the trans- parent dielectric layer in imagewise configuration simultaneous with application of a voltage between the metal surface and the transparent electrode, ~s a result of coincidence of imagewise illumination and application of an electric field, electron hole pairs are photoexcited in the metal layer at or near the interface of the metal and the dielectric layer resulting in the transfer of one species of photoexcited charge carrier to the dielectric layer. Upon separation of the metal layer and the dielectric, charge remains trapped at the surface of the dielectric and thereby forms a latent electrostatic image. This latent image is capable of development in the presence of light and may be used in the reproduction of more than one copy.