Patent · US Expired

Inspection apparatus of wiring board

US5740272A · kind A · utility

17Cited by
6References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 23, 1996
Grant dateApr 14, 1998
Priority date
Expiry dateFeb 23, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01J2005/0077
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An object of the invention is to shorten the inspection time of wiring board. A high frequency signal is applied to source signal wiring of a substrate member 12 put on a table 13 from signal feeding means 17 through terminals of a frame 14. A signal of which voltage absolute value is greater than the voltage amplitude of the high frequency signal and voltage polarity is positive is applied to a scanning wiring of the substrate member 12. An infrared image of the substrate member 12 with signal applied is taken by image pickup means 15. In image processing means 16, from the image data fed from the image pickup means 15, an infrared image changing in contrast depending on the emission of infrared rays is formed, and the infrared image is divided into plural regions equal in the size of wiring pattern. In control means 18, the image of each divided region is compared with images of plural adjacent regions, and difference is detected. When a difference is detected, it is judged there is a defect in that region.

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