US3843890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical-electrical web inspection system
Assignee: EIDP Inc
•
Filing: 1973-07-27
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Granted: 1974-10-22
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Expires: 1993-07-27
Abstract
Abstract An automatically calibrated flying spot web inspection system adapted to detect three different classes of defects and discriminate as to defect class. Electronic means responsive to a beam of radiation in either the reflection mode or the transmission mode detect sharp edge defects, diffuse edge defects and protracted duration defects.
Inventors
- 👤 J Anthony
- 👤 M Faulhaber
- 👤 E Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:49
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/89
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
174 words
A flying spot inspection system for web materials comprising: a radiation source, means traversing a beam of radiation from said source in a scan across said web, electronic means responsive to said beam of radiation in either the reflection mode or the transmission mode with respect to said web detecting the existence of three general classes of defects and discriminating said defects as to class, consisting of: 1. sharp edge defects, 2. diffuse edge defects and 3. protracted duration defects characterized by an amplitudeshifted pedestal of the optical-to-electrical transduction signal produced in said scan of said web, means responsive to said electronic means detecting said defects identifying web materials containing said defects and passing the remainder of said web materials as acceptable product, and automatic calibration means providing at the outset of each said scan said electronic means with an instantaneous basic reference voltage signal retained during the balance of each said scan determined by operation of said system with a preselected radiation attenuation filter replacing said web at the outset of said scan.
Claim 2
Dependent Claim
174 words
A flying spot inspection system for web materials comprising: a radiation source, means traversing a beam of radiation from said source in a scan across said web, electronic means responsive to said beam of radiation in either the reflection mode or the transmission mode with respect to said web detecting the existence of three general classes of defects and discriminating said defects as to class, consisting of: 1. sharp edge defects, 2. diffuse edge defects and 3. protracted duration defects characterized by an amplitudeshifted pedestal of the optical-to-electrical transduction signal produced in said scan of said web, means responsive to said electronic means detecting said defects identifying web materials containing said defects and passing the remainder of said web materials as acceptable product, and automatic calibration means providing at the outset of each said scan said electronic means with an instantaneous basic reference voltage signal retained during the balance of each said scan determined by operation of said system with a preselected radiation attenuation filter replacing said web at the outset of said scan.
Claim 3
Dependent Claim
4 words
diffuse edge defects and
Claim 4
Dependent Claim
4 words
diffuse edge defects and
Claim 5
Dependent Claim
95 words
A flying spot inspection system for web materials according to claim 1 wherein said electronic means for detection and discrimination of said sharp edge defects comprises: electrical differentiation means for both web pedestal signals and for said instantaneous basic reference voltage signal whereby the differentiated value of said instantaneous basic reference voltage signal is retained for the duration of said scan, and means grading as nonpassable sharp edge defects which produce signal magnitudes in the differentiated pedestal signal exceeding a preselected scaled proportion of the retained differentated value of said instantaneous basic reference voltage signal.
Claim 6
Dependent Claim
102 words
A flying spot inspection system for web materials according to claim 1 wherein said electronic means for the detection and discrimination of said diffuse edge defects comprises: means obtaining the logarithmic ratio of the instantaneous pedestal signal amplitudes throughout each full web width scan and said instantaneous basic reference voltage signal amplitude retained for the duration of said scan, means comparing said logarithmic ratio with a preselected threshold voltage level of preselected polarity for grading diffuse edge defects, and means grading as nonpassable all diffuse edge defects having said ratio magnitudes exceeding said preselected threshold voltage level for grading diffuse edge defects.
Claim 7
Dependent Claim
97 words
protracted duration defects characterized by an amplitude-shifted pedestal of the optical-to-electrical transduction signal produced in said scan of said web, means responsive to said electronic means detecting said defects identifying web materials containing said defects and passing the remainder of said web materials as acceptable product, and automatic calibration means providing at the outset of each said scan said electronic means with an instantaneous basic reference voltage signal retained during the balance of each said scan determined by operation of said system with a preselected radiation attenuation filter replacing said web at the outset of said scan.
Claim 8
Dependent Claim
97 words
protracted duration defects characterized by an amplitude-shifted pedestal of the optical-to-electrical transduction signal produced in said scan of said web, means responsive to said electronic means detecting said defects identifying web materials containing said defects and passing the remainder of said web materials as acceptable product, and automatic calibration means providing at the outset of each said scan said electronic means with an instantaneous basic reference voltage signal retained during the balance of each said scan determined by operation of said system with a preselected radiation attenuation filter replacing said web at the outset of said scan.
Claim 9
Dependent Claim
153 words
A flying spot inspection system for web materials according to claim 1 wherein said electronic means for the detection and discrimination of protracted duration defects characterized by an amplitude-shifted pedestal of said optical-to-electrical transduction signal produced in said scan of said web comprises: means measuring during each full web width scan the difference between the instantaneous logarithmic ratio and the time-averaged value from many previous scans of said logarithmic ratio of the instantaneous pedestal signal amplitudes throughout each full web width scan to said instantaneous basic reference voltage signal amplitude retained for the duration of said scan, means integrating said difference with respect to time, means comparing the output of said integrating means with a preselected threshold voltage level of preselected polarity for grading said protracted duration defects, and means grading as nonpassable all protracted duration defects having integrated difference magnitudes exceeding said preselected threshold voltage level for grading said protracted duration defects.
Claim 10
Dependent Claim
88 words
A flying spot inspection system for web materials according to claim 4 provided with means whereby said time-averaged value of the logarithmic ratio of the instantaneous pedestal signal amplitude throughout each full web width scan and said instantaneous basic reference voltage signal amplitude retained for the duration of said scan is held in storage over a multiplicity of said scans during which time logarithmic ratios determined during subsequent scans in which nonpassable protracted duration defects are detected are barred from inclusion in said time-averaged value of said ratio.
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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) | 1977-10-21 | 1978-04-22 | 1978-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-21 | 1982-04-22 | 1982-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-21 | 1986-04-22 | 1986-10-22 | $7700.00 | Window Closed / Lapsed |