Patent · US Expired

Method and apparatus for automatically inspecting and repairing an active matrix LCD panel

US5235272A · kind A · utility

46Cited by
22References
2Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 17, 1991
Grant dateAug 10, 1993
Priority date
Expiry dateJun 17, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S345/904
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

LCD panels are inspected in-process to measure pixel decay, turn-on time and parasitic capacitance and/or identify pixel defects and line defects. Prior to final assembly, panels identified as having sufficiently few repairable defects are repaired. Line defects may be repaired. Further pixel defects may be repaired when redundant structures are included by splicing out the defective TFT or storage capacitor and splicing in a redundant, built-in TFT or storage capacitor. The inspection and repair systems are linked through a repair file. The inspection system identifies each defect by type and location and includes such information in the repair file. The repair system accesses such file and follows a prescribed repair method for a given type of defect at the location of such defect. The inspection system includes an automated non-contact voltage imaging system. The repair system includes lasers and means for repairing defects by adding metallization.

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