Patent · US Expired

Bi-level display system

US3961134A · kind A · utility

12Cited by
3References
41Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 9, 1975
Grant dateJun 1, 1976
Priority date
Expiry dateMay 9, 1995

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N5/70
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Continuous tone images are displayed on a bi-level display device by establishing thresholds for each display element and actuating a particular element when its intensity .phi. bears a predetermine relationship to the established threshold. Thresholds .phi..sub.T are established by determining the average intensity .phi. of picture elements in the neighborhood of a particular display element, and by constraining the average to a narrower range according to a single value function of .phi. such as ##EQU1## WHERE .phi..sub.MAX IS THE MAXIMUM INTENSITY POSSIBLE AND .gamma. IS A CONSTANT WHICH CAN BE DETERMINED SUBJECTIVELY OR WHICH CAN BE RELATED TO THE NOISE IN THE PICTURE AREA.

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