Frequency domain enhancement of low-SNR flat residue/stain defects for effective detection
US11798153B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 9, 2020 |
| Grant date | Oct 24, 2023 |
| Priority date | — |
| Expiry date | Jul 11, 2042 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30148
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An inspection system is disclosed. The system includes a controller communicatively couplable with an inspection sub-system configured to receive illumination from a sample and generate image data. The controller includes one or more processors configured to execute program instructions causing the one or more processors to receive the image data, wherein the image data comprises at least one image, downsample the at least one image using bicubic interpolation or bilinear interpolation, transform the at least one image from a spatial domain to a frequency domain using a Fourier transform, filter frequencies higher than a threshold frequency from the at least one image, transform the at least one image from the frequency domain to the spatial domain using an inverse Fourier transform, and detect one or more flat-pattern defects in the at least one image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.