Method and apparatus for three dimensional edge tracing with Z height adjustment
US7120286B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 21, 2001 |
| Grant date | Oct 10, 2006 |
| Priority date | — |
| Expiry date | Jun 8, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F18/40
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for tracing an edge contour of an object in three dimensional space is provided. The method and apparatus is utilized in a computer vision system that is designed to obtain precise dimensional measurements of a scanned object. In order to save focusing time during an automatic tracing measurement, multiple images may be collected and saved for a number of Z heights for a particular position of the XY stage. These saved images can later be used to calculate a focal position for each edge point trial location in the selected XY area rather than requiring a physical Z stage movement. In addition, a Z height extrapolation based on the Z heights of previous edge points can significantly speed up the searching process, particularly for objects where the Z height change of a contour is gradual and predictable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.