Learning method and apparatus for detecting and controlling solder defects
US5621811A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 4, 1994 |
| Grant date | Apr 15, 1997 |
| Priority date | — |
| Expiry date | Feb 4, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N23/043
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus which incorporate self learning techniques for the detection of solder defects and for statistical process control of solding operations on printed circuit board assemblies (PCBA) are disclosed. The invention includes learning techniques which are used during the inspection of cross-sectional X-ray images of solder joints. These learning techniques improve measurement accuracy by accounting for localized shading effects, which can occur when inspecting double-sided printed circuit board assemblies. Two specific examples are discussed. The first is a method for detection of solder short defects. The second method utilizes learning to improve the accuracy of statistical process control (SPC) measurements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.