Method for characterizing material by analysis of speckles
US9830520B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 6, 2016 |
| Grant date | Nov 28, 2017 |
| Priority date | — |
| Expiry date | Sep 6, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/479
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method for characterizing material in which a surface is formed, by analysis of speckles generated on the surface by a coherent light beam by performing the computation of an autocorrelation function of the light intensity on the image and computation of the value of at least one criterion set up from said function, setting up an autocorrelation matrix of the light intensity of the image, computation of the discrete cosine transform of said matrix, and computation of the value of a characterization criterion such as the average on the image of the matrix trace obtained by the discrete cosine transform of the autocorrelation matrix, and computation of the value of at least one representative criterion of a phase shift distribution of the light beams diffused by the surface, said computation comprising computation of a wavelet transform of the image, and computation of the value of at least one criterion from the following group: average of the phases of the wavelet coefficients on the image, or standard deviation of the phases of the wavelet coefficients on the image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.