US4928313A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and system for automatically visually inspecting an article
Assignee: Novanta Inc
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Filing: 1989-05-19
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Granted: 1990-05-22
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Expires: 2009-05-19
Abstract
Abstract A method and system are disclosed for automatically visually inspecting an article such as an electronic circuit wherein both reference and non-reference algorithms are utilized to detect circuit defects. The system includes a pipelined cellular image processor which is utilized to implement the non-reference algorithm and an arithmetic logic unit (ALU) is coupled to the output of the cellular image processor to perform the reference method. The non-reference method includes a spaces and traces algorithm and the reference method includes a topology matching algorithm. The system also includes an algorithm for locating and gauging critical areas of the circuit with sub-pixel accuracy. The cellular image processor is supported by a matched host image processor system
Inventors
- 👤 Patrick F. Leonard
- 👤 Donald J. Svetkoff
- 👤 Robert W. Kelley
- 👤 Donald K. Rohrer
- 👤 E. North Coleman, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:49
CPC Classifications
G; G06; G06T; G06T7/00; G06T7/0002; G06T7/0004; G06T7/001; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/95; G01N21/956; G06T2207/00; G06T2207/30; G06T2207/30108; G06T2207/30148
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
242 words
A method for automatically and visually inspecting an article, the method comprising the steps of: acquiring a first set of digital image data representing a known good article, the image data representing a two dimensional reference image, processing the first set of image data to separate the reference image into at least two identifiable areas having a boundary therebetween; compressing the reference image in each of the two dimensions of the reference image, the step of compressing including the steps of reducing at least one of the areas of the reference image to an edge represented by a number of data points and reducing the number of data points representing the edge; storing the compressed reference image; acquiring a second set of digital image data representing a two-dimensional image of an article under inspection; processing the second set of digital image data to separate the image of the article under inspection into at least two identifiable areas having a boundary therebetween; retrieving the compressed reference image; regenerating the retrieved reference image, said step of regenerating including the step of regenerating the edge from the reduced number of data points, regenerating the at least one of the areas from the regenerated edge, and constructing border regions around at least one of the areas of the reference image to obtain a regenerated reference image; and matching the regenerated reference image and the image of the article under inspection to identify areas where mismatches occur.
Claim 2
Independent Claim
242 words
A method for automatically and visually inspecting an article, the method comprising the steps of: acquiring a first set of digital image data representing a known good article, the image data representing a two dimensional reference image, processing the first set of image data to separate the reference image into at least two identifiable areas having a boundary therebetween; compressing the reference image in each of the two dimensions of the reference image, the step of compressing including the steps of reducing at least one of the areas of the reference image to an edge represented by a number of data points and reducing the number of data points representing the edge; storing the compressed reference image; acquiring a second set of digital image data representing a two-dimensional image of an article under inspection; processing the second set of digital image data to separate the image of the article under inspection into at least two identifiable areas having a boundary therebetween; retrieving the compressed reference image; regenerating the retrieved reference image, said step of regenerating including the step of regenerating the edge from the reduced number of data points, regenerating the at least one of the areas from the regenerated edge, and constructing border regions around at least one of the areas of the reference image to obtain a regenerated reference image; and matching the regenerated reference image and the image of the article under inspection to identify areas where mismatches occur.
Claim 3
Dependent Claim
24 words
The method as claimed in claim 1 wherein the article includes electronic circuitry such as a multilayer thick-film circuit having a plurality of components.
Claim 4
Dependent Claim
31 words
The method as claimed in claim 1 or 2 including the step of measuring at least one dimension of one of the areas of the image of the article under inspection.
Claim 5
Dependent Claim
33 words
The method as claimed in claim 1 or 2 further comprising the step of checking the second set of processed data with at least one preselected geometrical constraint to identify areas of non-compliance.
Claim 6
Dependent Claim
28 words
The method as claimed in claim 4 wherein the step of checking includes the step of checking the second set of image data with a preselected width constraint.
Claim 7
Dependent Claim
29 words
The method as claimed in claim 4 wherein the step of checking includes the step of performing a series of neighborhood transformations on said second set of image data.
Claim 8
Dependent Claim
20 words
The method as claimed in claim 6 including the step of generating a bit map flagging the areas of non-compliance.
Claim 9
Dependent Claim
26 words
The method as claimed in claim 4 including the step of combining said areas of non-compliance and said areas where the mismatches occur to identify defects.
Claim 10
Independent Claim
241 words
A system for automatically, visually inspecting an article, the system comprising: means for acquiring first and second sets of digital image data, the first set of image data representing a two-dimensional reference image of a known good article and the second set of image data representing a two-dimensional image of the article under inspection; means for processing the first set of image data to separate the first set of image data into at least two identifiable areas having a boundary therebetween; means for compressing the reference image in each of the two dimensions of the reference image, said means for compressing including means for reducing at least one of the areas of the reference image to an edge represented by a number of data points and means for reducing the number of data points representing the edge; means for storing the compressed reference image; means for retrieving the stored compressed reference image; means for regenerating the reference image, said means for regenerating including means for regenerating the edge from the reduced number of data points representing the edge, means for regenerating the at least one of the areas of the reference image from the edge; and means for constructing border regions from the at least one of the areas of the reference image to obtain the regenerated reference image; and means for matching the regenerated reference image and the image of the article under inspection to identify areas where mismatches occur.
Claim 11
Independent Claim
241 words
A system for automatically, visually inspecting an article, the system comprising: means for acquiring first and second sets of digital image data, the first set of image data representing a two-dimensional reference image of a known good article and the second set of image data representing a two-dimensional image of the article under inspection; means for processing the first set of image data to separate the first set of image data into at least two identifiable areas having a boundary therebetween; means for compressing the reference image in each of the two dimensions of the reference image, said means for compressing including means for reducing at least one of the areas of the reference image to an edge represented by a number of data points and means for reducing the number of data points representing the edge; means for storing the compressed reference image; means for retrieving the stored compressed reference image; means for regenerating the reference image, said means for regenerating including means for regenerating the edge from the reduced number of data points representing the edge, means for regenerating the at least one of the areas of the reference image from the edge; and means for constructing border regions from the at least one of the areas of the reference image to obtain the regenerated reference image; and means for matching the regenerated reference image and the image of the article under inspection to identify areas where mismatches occur.
Claim 12
Dependent Claim
24 words
The system as claimed in claim 9 wherein the article includes circuitry such as a multilayer thick film circuit having a plurality of components.
Claim 13
Dependent Claim
31 words
The system as claimed in claim 9 wherein said means for matching includes an arithmetic logic unit for comparing the regenerated reference image and the second set of processed image data.
Claim 14
Dependent Claim
30 words
The system as claimed in claim 10 further comprising means for checking the set of processed image data with at least one preselected geometrical constraint to identify areas of non-compliance.
Claim 15
Dependent Claim
28 words
The system as claimed in claim 12 wherein said means for checking includes a pipeline of serial neighborhood transformation stages for processing the second set of image data.
Claim 16
Dependent Claim
47 words
The system as claimed in claim 13 wherein said means for matching includes an arithmetic logic unit selectively coupled to the output of the pipeline and selectively coupled to said means for regenerating for combining the regenerated reference image and the second set of image process data.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-05-21 | 1993-11-20 | 1994-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-21 | 1997-11-20 | 1998-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-21 | 2001-11-20 | 2002-05-22 | $7700.00 | Window Closed / Lapsed |