Degradation compensation of photoreceptor sensitivity for electrophotographic copying machine
AssigneeSharp Kabushiki Kaisha
InventorsShunju Anzai, Yoshiaki Imanaka
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Abstract
An electrophotographic copying machine is provided having a photoreceptor, a corona discharger, a lamp, and a compensation circuit. The corona discharger is activated to provide a corona discharge toward the photoreceptor to uniformly and initially charge the surface of the photoreceptor. The lamp is illuminated at the same time as the corona discharge of the corona discharger to improve the charging on the photoreceptor. The compensation circuit is activated to provide an exponential voltage to be applied to the lamp in proportion to the sensitivity degradation of the photoreceptor, to thereby compensate the sensitivity degradation of the photoreceptor.
Claims4
An electrophotographic copying machine comprising:
- photoreceptor means for forming a latent image thereon;
- corona discharge means for providing corona discharging onto said photoreceptor means;
- lamp means for emitting light toward said photoreceptor means simultaneously with the discharging of said corona discharge means;
- and
- control means for controlling activation of said lamp means so that an amount of light emitted by said lamp means is proportional to an exponential degradation in the sensitivity of said photoreceptor means.
Dependencies are inferred from the claim text.