The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 30, 2004
Filed:
Feb. 05, 1999
Joseph Scola, Medfield, MA (US);
Lowell Jacobson, Grafton, MA (US);
Cognex Corporation, Natick, MA (US);
Abstract
A method and apparatus are disclosed for analyzing a boundary of an object. An embodiment for determining defects of a boundary to sub-pixel precision and an embodiment for fast correlation scoring are disclosed. The boundary is analyzed by matching a first boundary, such as a model of an ideal object boundary, to a second boundary, such as the boundary of an object being produced at a factory. The boundaries are represented as a set of indexed vertices, which are generated by parsing the boundaries into a set of segments. One embodiment refines the parse through merging segments and reassigning data points near the endpoints of the segments. The model produced is very accurate and is useful in other applications. To analyze the boundaries, the sets of indexed vertices are matched, and optionally the segmentation of the second boundary is refined to increase the extent of matching. The extent of matching yields a correlation score and/or the matching allows a characteristic class of the first set of segments to be associated with the second set of segments. The class and data points of the runtime segments are used to measure defects in the second set of segments, and thus in the boundary of the object.