Patent · US Expired

Apparatus for selecting originals for copying on the basis of image sharpness

US3981579A · kind A · utility

10Cited by
6References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 7, 1973
Grant dateSep 21, 1976
Priority date
Expiry dateSep 7, 1993

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B27/72
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The density of neighboring portions of each of a plurality of successive originals is monitored. An original is copied only if the original is comprised of at least one pair of monitored neighboring portions differing from each other in density by an amount exceeding a reference value.

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