Method of and device for inspecting pattern of printed circuit board
US5161202A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 16, 1991 |
| Grant date | Nov 3, 1992 |
| Priority date | — |
| Expiry date | Jul 16, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30141
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Respective images of a conductive pattern and through holes of a printed circuit board are obtained. The through holes are classified into normal through holes having a relatively large diameter and mini via holes having a comparatively small diameter. The mini via hole image is enlarged to become an enlarged mini via hole image (SHSm). The image of the conductive pattern has hole parts therein, which are filled with images generated from the normal through hole image and the mini via hole image to obtain a corrected pattern image (CPS). The edge of the corrected pattern image is detected and enlarged to obtain an enlarged edge image (SES). The enlarged edge image is classified into two areas, one of which overlaps with the enlarged mini via hole image (SHSm). These two areas are subjected to inspection in different inspection modes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.