Patent · US Expired

Method to reduce perceptual contouring in display systems

US5751379A · kind A · utility

77Cited by
4References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 4, 1996
Grant dateMay 12, 1998
Priority date
Expiry dateOct 4, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N2005/7466
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method of pulse width modulation using a spatial light modulator (40) with a finite transition time. The method uses m bits per sample to digitize the incoming data, but apportions the LSB times for pulse width modulation based upon m-1 bits. The current video frame displays all of the bits for each sample, except for the LSBs for each sample. The next video frame displays all of the bits for each sample, adding one more LSB for dividing up the frame time. The first frame could use either the additional LSB time and display no data, or it could use only that number of LSB times it needs. In the latter, the system will have to adjust to different partitions of the frame time for alternating frames. The system includes a spatial light modulator (40), a memory (42), a formatter (48), a sequence controller (44) and a toggle circuit (46), to perform this method.

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