Method of inspecting curved surface and device for inspecting printed circuit board
US7062080B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 18, 2002 |
| Grant date | Jun 13, 2006 |
| Priority date | — |
| Expiry date | Oct 6, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/95646
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A circuit board with lead-free solder is inspected by using light sources with different colors at different angles to obtain an image having a plurality of color components. For each pixel within an area in the obtained image, the brightness of a white component generated by mixing all of the color components is extracted. The brightness of each of the color components of each pixel is reduced by an amount corresponding to the extracted brightness of the white component and is adjusted such that the brightest of the color components becomes more strongly emphasized compared to the others, than the brightness before the brightness-reducing process was carried out and the loss in total brightness caused by the brightness-reducing process is restored. The image with restored brightness is displayed and the surface condition of the solder is judged on the basis of the distributions of the color components of this image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.