Browse Prior Art Database

Original Publication Date: 1977-Feb-28
Included in the Prior Art Database: 2004-Mar-29

Publishing Venue

Xerox Disclosure Journal


in an electrophotographic printing machine, it is desirable to inactivate the screening system when a slide is being reproduced as an opaque copy. The screening system employs a light source energized by power supply 10 and a screen disposed closely adjacent to the photoconductive surface. The screen is disposed in the path of the light rays so that a screened electrostatic latent image is recorded on the photoconductive surface. In the screening mode of operation switch 12 is closed. Switch 14 is associated with the platen cover. When the platen cover is closed, switch 14 is closed. Switch 14 is opened with an open platen cover. In the slide copying mode, the platen cover is opened and switch 14 remains opened inactivating the screening system. Contrawise, when an opaque original document is being reproduced, the platen cover is closed as in switch 14. Thus, the screening system is enabled permitting a screened copy to be reproduced. The screening system is enabled when power supply 10 is coupled to the light source. Contrawise, the screening system is disabled when power supply 10 is disconnected from the light source. Thus, opening and closing switch 14 will enable and disable the screening system.