LCD panel test system and test method thereof
US5994916A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 4, 1997 |
| Grant date | Nov 30, 1999 |
| Priority date | — |
| Expiry date | Jun 4, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S345/904
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An LCD panel test system for measuring voltages in the pixels of LCD with high signal to noise (S/N) ratio. The LCD test system includes a sweep timing generator for generating clock signals and control signals for driving pixels in an LCD panel, a driver for generating a reference voltage to be supplied to the pixels in the LCD, a current-voltage (IV) conversion circuit for receiving a signal from the pixels to convert the same to a corresponding voltage signal, a sample and hold circuit for sampling the voltage signal from the IV conversion circuit and temporarily holding the sampled voltage, an A/D converter for converting the sampled voltage to a digital signal, and an image processor for processing the digital signal from the A/D converter to detect defective pixels in the LCD panel based on relative levels of the output signals from the video terminal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.