Patent · US Expired

Scanning and reproduction of pictorial images

US3984187A · kind A · utility

7Cited by
4References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 13, 1975
Grant dateOct 5, 1976
Priority date—
Expiry dateFeb 13, 1995

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03B27/725
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An original bears a pictorial image, or the like. The original is illuminated with first and second light and the image on the original is projected onto a copy carrier. The spatial variation of the intensity of the first light after the first light has been modulated in intensity by the image on the original is detected. The contrast of the image projected onto the copy carrier compared to the contrast of the image on the original is changed by changing the spatial variation of the second light in dependence upon the detected spatial variation of the intensity of the modulated first light.

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