Patent · US Expired

Electrophotographic copying apparatus for effecting a copying operation on the basis of a set copying characteristic

US4534642A · kind A · utility

9Cited by
2References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 21, 1982
Grant dateAug 13, 1985
Priority date
Expiry dateDec 21, 2002

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/065
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An electrophotographic copying apparatus comprises a photoconductive drum, a charger for electrically charging the drum, an exposure unit for exposing the drum to form a latent image on the drum which correspond to the pattern of a document, a developer unit for developing the latent image, using one-component toner, a transfer unit for transferring a toner image to a paper sheet and a fixer unit for fixing the toner image. In copying the document pattern, a document density-copy density characteristic, i.e. .gamma. characteristic, is set in accordance with the document density. According to the .gamma. characteristic the amount of exposure and the bias voltage to be applied on the developer unit are varied.

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