Pattern defect detection apparatus
US5774574A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 28, 1995 |
| Grant date | Jun 30, 1998 |
| Priority date | — |
| Expiry date | Nov 28, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30141
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In a printed substrate inspection apparatus for dividing an inspection objective image into divided areas and comparing divided areas with a plurality of reference images which are included in a standard pattern image, an affect of a positional deviation of the inspection objective image is obviated. A size K of each inspection objective divided area is determined in such a manner that a difference between a positional deviation within each inspection objective divided area and a positional deviation of the inspection objective image does not exceed a quantity corresponding to 1 pixel. Further, a maximum shifting quantity M of the reference images with respect to each inspection objective divided area is set equal to or larger than a positional deviation maximum value of the inspection objective image. A positional deviation of the inspection objective image as a whole does not manifests itself as an inclination or a distortion within each inspection objective divided area. The plurality of reference images include images which correspond to images of the inspection objective divided areas. Hence, comparison inspection is accurate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.