Patent · US Expired

Image density control method for an image forming apparatus for reducing background contamination of a photoconductive drum

US5198861A · kind A · utility

33Cited by
3References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 28, 1992
Grant dateMar 30, 1993
Priority date
Expiry dateJan 28, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G2215/00042
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An image density control method for an image forming apparatus determines the density of a toner image formed on a photoconductive element by a reflection type photosensor and, if the density is low, supplies a toner to a developing unit. A latent image representative of a reference pattern is electrostatically formed on the photoconductive element and then developed by a toner supplied from the developing unit. The supply of a toner to the developing unit is controlled on the basis of the outputs of the sensor associated with the area of the photoconductive element where the pattern image exists and a non-image area. A particular bias voltage is applied to the developing unit for each of the image area and non-image area.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.