Patent · US Expired

Variable magnification copying machine

US4803525A · kind A · utility

0Cited by
3References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 21, 1986
Grant dateFeb 7, 1989
Priority date
Expiry dateNov 21, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/041
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A variable magnification copying machine for guiding light reflected from an original onto a photosensitive body through means of a plurality of mirrors and a lens system and for forming a latent image of the original upon the photosensitive body includes a variable magnification optical apparatus. The variable magnification optical apparatus selects one of at least two variable magnification modes based upon U variable and U fixed systems in each one of at least two regions obtained by dividing a variable magnification range and varies the magnification by a combination of the variable magnification modes. The variable magnification mode based upon the U variable system changes the optical path length from a surface of the original to the photosensitive body so as to vary the magnification while maintaining the focal length of the lens system constant. The variable magnification mode based upon the U fixed system changes the focal length of the lens system so as to vary the magnification while maintaining the optical path length constant.

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