US5850468A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flaw detection apparatus
Assignee: Panasonic Holdings Corp
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Filing: 1998-01-16
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Granted: 1998-12-15
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Expires: 2018-01-16
Abstract
Abstract A flaw detection apparatus detects a flaw formed on an object's surface based on a digital image data indicative of said object's surface as a group of plural pixels utilizing the image processing technique. An image processor is provided for detecting a direction in which each of group extends to combine a plurality of groups extending in substantially the same direction. The image processor further produces a flaw signal indicating sizes of thus combined groups.
Inventors
- 👤 Haruhiko Yokoyama
- 👤 Akira Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:30
CPC Classifications
G; G06; G06T; G06T7/00; G06T7/0002; G06T7/0004; G06T7/0006; G06T7/60; G06T7/62; G06T7/66; G06T2207/00; G06T2207/30; G06T2207/30108; G06T2207/30164
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
194 words
A flaw detection apparatus for detecting a flaw formed on a surface of an object based on a plurality of first digital image data representing said surface as a plurality of first groups of plural pixels, each pixel of each first group being adjacent to each other, said apparatus comprising: first direction detection means for detecting a direction in which each first group extends based on the axis quadratic moment of each of said first groups by: a)first calculating the axis quadratic moment of each of said first groups, then b) assigning a value for the major axis angle of each of said first groups; first cluster means for combining said first groups that are disconnected and extend in directions different from each other less than a first predetermined degree based on the respective detected axis quadratic moment of each of said first groups and based on said major axis angle of each of said first groups; and first flaw signal producing means for producing a first flaw signal indicating sizes of said combined groups based on an area of said combined first groups and a rectangular circumscribing area of said combined first groups.
Claim 2
Dependent Claim
194 words
A flaw detection apparatus for detecting a flaw formed on a surface of an object based on a plurality of first digital image data representing said surface as a plurality of first groups of plural pixels, each pixel of each first group being adjacent to each other, said apparatus comprising: first direction detection means for detecting a direction in which each first group extends based on the axis quadratic moment of each of said first groups by: a)first calculating the axis quadratic moment of each of said first groups, then b) assigning a value for the major axis angle of each of said first groups; first cluster means for combining said first groups that are disconnected and extend in directions different from each other less than a first predetermined degree based on the respective detected axis quadratic moment of each of said first groups and based on said major axis angle of each of said first groups; and first flaw signal producing means for producing a first flaw signal indicating sizes of said combined groups based on an area of said combined first groups and a rectangular circumscribing area of said combined first groups.
Claim 3
Dependent Claim
60 words
A flaw detection apparatus as claimed in claim 1, wherein said first flaw signal producing means comprises: first flaw coefficient determining means for calculating the area of said combined first groups to determine a first flaw coefficient; and second flaw coefficient determining means for calculating the rectangular circumscribing area of said combined first groups to determine a second flaw coefficient.
Claim 4
Dependent Claim
39 words
A flaw detection apparatus as claimed in claim 2, further comprising reference flaw signal means for providing a reference flaw signal indicative of a flaw range of said first and second flaw coefficients for the detection of the flaw.
Claim 5
Dependent Claim
147 words
A flaw detection apparatus as claimed in claim 3, wherein said reference flaw signal means comprises: digital image signal producing means for producing a second digital image signal indicative of a second flaw on the surface of the object represented as a plurality of second groups of plural pixels; second direction detection means for detecting a direction in which each second group extends; second cluster means for combining said second groups extending in directions different from each other less than a second predetermined degree; third flaw coefficient determining means for calculating an area of said combined second groups to determine a third flaw coefficient; fourth flaw coefficient determining means for calculating an area of rectangular region circumscribing said combined second groups to determine a fourth flaw coefficient; and evaluation means for evaluating the distribution of said third and fourth flaw coefficients to determine a second flaw range.
Claim 6
Dependent Claim
117 words
A flaw detection apparatus for detecting a flaw formed on a surface of an object based on a digital image data indicative of said surface as a plurality of groups of plural pixels adjacent to each other, said apparatus comprising: minor axis quadratic moment determining means for obtaining a minor axis quadratic moment of a combination of two of said groups that are disconnected by calculating one minor axis quadratic moment of a combined two groups; comparator means for comparing said determined minor axis quadratic moment with a predetermined minor axis quadratic moment; and cluster means for combining said two groups when said determined minor axis quadratic moment is less than said predetermined minor axis quadratic moment.
Claim 7
Dependent Claim
117 words
A flaw detection apparatus for detecting a flaw formed on a surface of an object based on a digital image data indicative of said surface as a plurality of groups of plural pixels adjacent to each other, said apparatus comprising: minor axis quadratic moment determining means for obtaining a minor axis quadratic moment of a combination of two of said groups that are disconnected by calculating one minor axis quadratic moment of a combined two groups; comparator means for comparing said determined minor axis quadratic moment with a predetermined minor axis quadratic moment; and cluster means for combining said two groups when said determined minor axis quadratic moment is less than said predetermined minor axis quadratic moment.
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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) | 2001-12-14 | 2002-06-15 | 2002-12-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-12-14 | 2006-06-15 | 2006-12-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-12-14 | 2010-06-15 | 2010-12-15 | $7700.00 | Window Closed / Lapsed |