Patent · US Expired

Flat panel display inspection system

US5764209A · kind A · utility

80Cited by
23References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 22, 1995
Grant dateJun 9, 1998
Priority date
Expiry dateFeb 22, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2320/0693
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An improved testing system and method for testing a flat-panel display is disclosed herein. A display is positioned under a high resolution camera for detection of, for example, brightness uniformity across the display. Errors in the detected image due to aliasing are avoided in the present invention by incrementally shifting the displayed image relative to the camera and detecting the displayed image at various shifted positions. A resulting accurate display can then be reconstructed by identifying those detector pixels generating a maximum signal. A single image may then be reconstructed using only those detected maximum pixel signals. The reconstructed image will be free of aliasing. The reconstructed image may then be analyzed electronically, and any anomalies in the pixels forming the display panel can then be accurately detected. Anomalies due to uneven brightness across the display can be corrected by programming a memory chip for the particular display panel to permanently compensate the display driver signals for each display pixel to eliminate such anomalies in the display. Other tests for viewing angles and chromaticity may also be performed.

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