Fast high-accuracy multi-dimensional pattern inspection
US6850646B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 10, 2003 |
| Grant date | Feb 1, 2005 |
| Priority date | — |
| Expiry date | Nov 10, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06V10/754
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus are provided for identifying diffe rences between a stored pattern and a matching image subset, where variations in pattern position, orientation, and size do not give rise to false differences. The invention is also a system for analyzing an object image with respect to a model pattern so as to detect flaws in the object image. The system includes extracting pattern features from the model pattern; generating a vector-valued function using the pattern features to provide a pattern field; extracting image features from the object image; evaluating each image feature, using the pattern field and an n-dimensional transformation that associates image features with pattern features, so as to determine at least one associated feature characteristic; and using at least one feature characteristic to identify at least one flaw in the object image. The invention can find at least two distinct kinds of flaws: missing features, and extra features. The invention provides pattern inspection that is faster and more accurate than any known prior art method by using a stored pattern that represents an ideal example of the object to be found and inspected, and that can be tra…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.