Patent · US Expired

Precision time tracking line generator

US4491925A · kind A · utility

4Cited by
8References
44Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 19, 1981
Grant dateJan 1, 1985
Priority date
Expiry dateJun 19, 2001

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G1/12
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A display system line generator network having an error correction feedback loop which achieves high positional accuracy for both plan position indicators PPI and synthetic character and line data. Digital reference position and relative beam motion data are fed into separate D/A converters. The staircase effect at the output of the D/A that processes the relative beam motion data is eliminated in a constant current integrator. The output of the integrator is combined with the reference position signal in a summing amplifier and the summed signal is fed to a deflection amplifier. A feedback circuit picks off the inputs to the summing amplifier and uses their comparison to synchronize time with beam position by compensating for errors due to component drift and aging.

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