Patent · US Expired

On-screen display

US4549218A · kind A · utility

7Cited by
6References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 30, 1983
Grant dateOct 22, 1985
Priority date
Expiry dateSep 30, 2003

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N5/44504
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

To prevent undesired bending of vertical bar type information displayed on the screen of a kinescope due to kinescope beam current variations, modifying circuits are provided for reducing the beam current threshold level of an automatic beam current limiter stage to a lower threshold level whenever vertical bar type information is displayed.

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