LCD panel test apparatus
US5734158A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 24, 1996 |
| Grant date | Mar 31, 1998 |
| Priority date | — |
| Expiry date | Apr 24, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/1309
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An LCD panel test apparatus automatically detects defects of the LCD panel under test. The LCD panel test apparatus includes: a first polarizing plate provided above said LCD panel under test and having a predetermined polarizing direction; a second polarizing plate provided below the LCD panel having a polarizing direction perpendicular to that of the first polarizing plate; a back light provided under the second polarizing plate to illuminate the LCD panel; a camera to monitor light signals passing through the first polarizing plate; a third polarizing plate mounted on the same horizontal plane of the first polarizing plate; a polarizing plate driver for driving the first and third polarizing plates to place either one of the first or third polarizing plate right above the LCD; an analog-digital converter to convert an analog signal from the camera into digital data; an image processing CPU which performs a signal processes for the digital data received from the analog-digital converter; and an LCD panel driver which provides a drive signal to the LCD panel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.