Method for detecting a defect on a surface by multidirectional lighting and associated device
US10648920B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 5, 2017 |
| Grant date | May 12, 2020 |
| Priority date | — |
| Expiry date | Apr 5, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/8816
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for detecting a defect on a surface (12) by multidirectional lighting includes acquiring a plurality of images of the surface (12) using an optical device (14) having an optical axis, each image being acquired with a lighting of the surface along a lighting direction (E, E′) given for each point of the surface (12) and an optical direction (O), the images being acquired with different lighting directions (E, E′) or different combinations and/or with different optical directions (O); for each point, calculating a plurality of parameters, the parameters including coefficients of an equation characterizing the response of said point of the surface as a function of the lighting direction (E, E′) and an observation direction (B, B′); and deducing from the calculated parameters whether the surface (12) has a defect at said point.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.