Patent · US Expired

Electrostatic copying apparatus

US4533233A · kind A · utility

8Cited by
11References
31Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 14, 1983
Grant dateAug 6, 1985
Priority date
Expiry dateApr 14, 2003

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/28
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A variable magnification electrostatic copying apparatus comprising a transparent plate on which to place a document to be copied, an optical system for projecting the image of the document onto an electrostatographic photosensitive member at any desired projecting ratio selected from a plurality of projecting ratios in an exposure zone located along the moving path of the photosensitive member, and a driving means for moving at least a part of the optical system and the transparent plate relative to each other. The optical system includes at least one position-variable optical element assembly adapted to be held at any of a plurality of positions corresponding to the aforesaid plurality of projecting ratios. The variable magnification electrostatic copying apparatus includes a unique improved means for varying the projecting ratio of the optical system by moving the position-variable optical element assembly.

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