Patent · US Expired

Image forming apparatus and method having image density correcting function

US5351107A · kind A · utility

35Cited by
14References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 23, 1993
Grant dateSep 27, 1994
Priority date
Expiry dateMar 23, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G2215/00042
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

High and low density test patterns are formed from pattern generating unit as toner patterns on a photosensitive drum, and attached toner amounts corresponding to the test patterns are detected by toner density detecting unit under the control of a control circuit which calculates the differences between the attached toner amounts of the high and low density portions and respective target values, wherein, when the calculated differences do not fall within respective predetermined ranges, the exposure conditions of an optical system and the bias voltage of a developing unit, or the exposure amount of the optical system and the bias voltages of a charger and the developing unit, or the bias voltages of the charger and the developing unit and the light-emission period of the optical system are renewed.

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