Patent · US Expired

Photographic image definition improvement

US4327172A · kind A · utility

4Cited by
11References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 16, 1980
Grant dateApr 27, 1982
Priority date
Expiry dateDec 16, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S430/135
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The definition of a photographic emulsion of the positive acting type that would normally produce a positive image is improved by normally exposing the emulsion to actinic radiation and developing the photographic emulsion, bleaching it, exposing the emulsion again to actinic radiation and redeveloping it to reverse the image that would normally result on the film.

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