PHOTORECEPTOR ERASE DEVICE
Original Publication Date: 1987-Feb-28
Included in the Prior Art Database: 2004-Apr-04
Xerox Disclosure Journal
The cyclic stability of selenium alloy photoreceptor electrical-characteristics is very substantially dependent on interactions with other xerographic engine subsystems. The erase subsystem is a case in point.
XEROX DISCLOSURE JOURNAL
PHOTORECEPTOR ERASE DEVICE Proposed Classification Geoffrey M. T. Foley
James M. Markovics
U.S. C1.355115 Int. C1. G03g 21/00
The cyclic stability of selenium alloy photoreceptor electrical- characteristics is very substantially dependent on interactions with other xerographic engine subsystems. The erase subsystem is a case in point.
There are various alternative schemes for erasing electrostatic latent images on a photoreceptor such as erase lamps, which produce no corona effluents, but must have an intensity sufficient to discharge the photoreceptor to a residual potential. Discharge to residual potential implies transport of carriers at low electric fields which is precisely the condition under which the probability of carrier trapping is highest. Thus, buildup of the residual potential is enhanced and consequent effects can be expected on background voltage cycleup and dark development potential (VDDP). Moreover, any wavelengths in the lamp spectrum which are bulk absorbed by the photoreceptor create new trapping or dark decay centers.
A.C. corotrons represent an alternative to erase lamps in choice of erase Subsystems. Voltage leveling of the electrostatic image in the photoreceptor via an A.C. corotron does not involve the transport of carriers through the photoreceptor at low fields. A.C. corotrons do, however, generate large quantities of corona effluents which can contribute to cyclic instabilities of selenium alloy photoreceptors, e.g. enhanced dark decay. In addition, the level of corona effluents is frequently non-uniformly distributed across the photoreceptor tending to be highest in the center and lowest at the edges, causing the effluent driven instability to form a significant "smile" in VDDP from inboard to outboard across the photoreceptor.
A mouse type brush with a conductive fiber pile provides perfect voltage leveling of the electrostatic image while avoiding (a) transport of charge through the photoreceptor at low fields and (b) generation of significant quantities of corona e...