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US4349880A Expired / Lapsed US ⏱️ 0.0 years remaining

Inspection system for detecting defects in regular patterns

Assignee: RCA Licensing Corp
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Filing: 1980-06-30
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Granted: 1982-09-14
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Expires: 2000-06-30
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Abstract

Abstract The inspection system detects defects in regular patterns wherein the elements of the patterns may have variations in period. In the system a camera, having a photoelectric sensor therein, is mechanically moved to permit the sensor to scan and detect the elements of a pattern. The system includes circuitry for processing the output of the sensor. The circuitry includes portions for quantizing the sensor output signal, for storing the quantized signal of a portion of a scan, for determining element period from the quanitized signal and for controlling the output of the storage portion at times related to element period. The circuitry also includes portions for correlating the output from the storing portion with a real time quantized signal of the same scan and for indicating the presence of an error related to a pattern defect in response to a miscorrelation signal from the correlating portion.

Inventors

  • 👤 Peter D. Southgate
  • 👤 John P. Beltz

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 22:04
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/95; G01N21/956; G06; G06T; G06T7/00; G06T7/0002; G06T7/0004; G06T7/0006; G06T2207/00; G06T2207/30; G06T2207/30108; G06T2207/30148

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 152 words
An inspection system for detecting defects in regular patterns wherein the elements of the patterns have variations in spatial period, said system comprising means for scanning and detecting the elements of a pattern, means for processing an output signal from said means for scanning and detecting during scanning, said means for processing including means for quantizing the output signal from the scanning and detecting means into binary digital signals, main storage means for storing the quantized signal of a portion of a scan, means for determining element period from the quantized signal and for controlling the output of said main storage means at times related to element period, means for correlating the output from said main storing means with a real time quantized signal of the same scan, and means for indicating the presence of an error related to a pattern defect in response to a miscorrelation signal from said correlating means.
Claim 2
Dependent Claim 152 words
An inspection system for detecting defects in regular patterns wherein the elements of the patterns have variations in spatial period, said system comprising means for scanning and detecting the elements of a pattern, means for processing an output signal from said means for scanning and detecting during scanning, said means for processing including means for quantizing the output signal from the scanning and detecting means into binary digital signals, main storage means for storing the quantized signal of a portion of a scan, means for determining element period from the quantized signal and for controlling the output of said main storage means at times related to element period, means for correlating the output from said main storing means with a real time quantized signal of the same scan, and means for indicating the presence of an error related to a pattern defect in response to a miscorrelation signal from said correlating means.
Claim 3
Dependent Claim 30 words
The inspection system as defined in claim 1 wherein said processing means includes second storage means at the output of said quantizing means for storing a complete quantized scan signal.
Claim 4
Dependent Claim 35 words
The inspection system as defined in claim 2 wherein said processing means includes means, which include said second storage means, for gating out incomplete quantized signals to prevent their storage in said main storage means.
Claim 5
Dependent Claim 32 words
The inspection system as defined in claim 2 wherein said processing means includes means, which include said second storage means, for indicating alignment of the scanning and detecting means with a pattern.
Claim 6
Dependent Claim 18 words
The inspection system as defined in claim 1 wherein said processing means includes means for determining pattern type.
Claim 7
Dependent Claim 22 words
The inspection system as defined in claim 1 wherein said processing means includes means for visually displaying the spacing between pattern elements.
Claim 8
Dependent Claim 50 words
The inspection system as defined in claim 1 wherein said processing means includes a leading edge detector located between the output of said main storage means and an input of said means for determining and controlling for detecting the transition from a clear area to an element of a pattern.
Claim 9
Dependent Claim 23 words
The inspection system as defined in claim 1 wherein said processing means includes means for manually adjusting the sensitivity of the correlating means.
Claim 10
Dependent Claim 47 words
The inspection system as defined in claim 1 wherein said processing means includes another storage means for storing a miscorrelation signal from the correlating means for a scan and means for comparing the stored miscorrelation signal with an output of the correlating means for a subsequent scan.
Claim 11
Dependent Claim 161 words
An inspection system for detecting defects in regular patterns wherein the elements of the patterns have variations in spatial period, said system comprising a video sensor positioned to receive light from a regular pattern, means for scanning the video sensor over the regular pattern, means for processing an output signal from the video sensor during scanning, said means for processing including means for quantizing the output signal from the video sensor into binary digital signals, a variable length shift register for storing the quantized signal of a portion of a scan, means for determining element period from the quantized signal and for controlling the output of said variable length shift register at times related to element period, means for correlating the output from variable length shift register with a real time quantized signal of the same scan, and means for indicating the presence of an error related to a pattern defect in response to a miscorrelation signal from said correlating means.
Claim 12
Dependent Claim 161 words
An inspection system for detecting defects in regular patterns wherein the elements of the patterns have variations in spatial period, said system comprising a video sensor positioned to receive light from a regular pattern, means for scanning the video sensor over the regular pattern, means for processing an output signal from the video sensor during scanning, said means for processing including means for quantizing the output signal from the video sensor into binary digital signals, a variable length shift register for storing the quantized signal of a portion of a scan, means for determining element period from the quantized signal and for controlling the output of said variable length shift register at times related to element period, means for correlating the output from variable length shift register with a real time quantized signal of the same scan, and means for indicating the presence of an error related to a pattern defect in response to a miscorrelation signal from said correlating means.

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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) 1985-09-13 1986-03-15 1986-09-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-09-13 1990-03-15 1990-09-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-09-13 1994-03-15 1994-09-14 $7700.00 Window Closed / Lapsed

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