Patent · US Expired

Method for inspecting a flexible printed circuit

US6333633A · kind A · utility

4Cited by
2References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 26, 1999
Grant dateDec 25, 2001
Priority date
Expiry dateJul 26, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/2805
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

After a flexible printed circuit is left under an atmosphere of a water vapor pressure of not lower than 30 mmHg so as to absorb moisture, a voltage is applied between two wiring portions to thereby measure an insulation resistance value between the wiring portions during the voltage application. The quantity .DELTA.log(R) of the change of the insulation resistance value at regular intervals is obtained. An examination is made as to whether the maximum of the quantity .DELTA.log(R) of the change of the insulation resistance value is not larger than a predetermined reference value or not. From this examination, a judgment is made as to whether the flexible printed circuit is good or not.

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