Patent · US Expired

System for measuring and detecting printed circuit wiring defects

US4650333A · kind A · utility

54Cited by
19References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 12, 1984
Grant dateMar 17, 1987
Priority date
Expiry dateApr 12, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/2806
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A non-contact system for detecting printed circuit wiring defects and for measuring circuit feature height relative to a substrate. The system has an energy source for illuminating the substrate and circuit features and a scanner for both instantaneously receiving energy reflected from the substrate and circuit features and for generating a signal in response to the reflected energy, which signal is adapted to vary with the intensity of the reflected energy. An analyzer is connected to the scanner for correlating the generated signal to a measurement representative of the height of the circuit features relative to the substrate. Variations and non-uniformity of the substrate surface due to bending, warpage or other causes can be accounted for so as to provide an accurate measurement of the height of a circuit feature relative to the substrate surface on which it is mounted.

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