Patent · US Expired

Electrostatographic apparatus comprising document density sensing means

US4200391A · kind A · utility

45Cited by
3References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 21, 1978
Grant dateApr 29, 1980
Priority date
Expiry dateAug 21, 1998

Classification

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

Abstract

Prior to optical scanning of an original document (14) for producing an electrostatic image thereof on a photoconductive drum (12), the optical density of the document (14) is sensed and a light image intensity and a developing bias voltage are set in accordance with a sensed minimum or background density of the document (14).

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