US3871773A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and apparatus for detecting defects and the position thereof in transparent articles
Assignee: PPG Industries Inc
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Filing: 1973-04-24
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Granted: 1975-03-18
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Expires: 1993-04-24
Abstract
Abstract A method of and apparatus for detecting defects such as pointtype and B-type defects in a transparent article, e.g. a glass ribbon, and determining position of the defect as a function of position in the article are disclosed. A positioning beam and a scanning beam are transmitted onto the surface of an oscillating directional mirror. The two beams are reflected from the oscillating directional mirror onto a concave reflecting surface. As the directional mirror oscillates, the two beams are synchronously displaced across the reflecting surface. The scanning beam is transmitted from the reflecting surface through the article along a scan path to scan contiguous lateral portions of the glass ribbon while the positioning beam is transmitted from the reflecting surface onto position sensing facilities. Facilities are provided for sensing intensity changes of the scanning beam which are caused by defects along the scan path. The position sensing facilities are actuated by the positioning beam to indicate the position of the scanning beam along the scan path to determine the position of the defects in the article.
Inventors
- 👤 Jr Hugh E Shaw
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:10
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/89; G01N21/892; G01N21/896
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
198 words
A method of determining defects in a glass ribbon as a function of position in the glass ribbon, comprising the steps of: directing a first beam of light toward a first surface of the glass ribbon as a scanning beam of light; directing a second beam of light toward position sensing means as a positioning beam of light; synchronously displacing (1) the scanning beam of light relative to the surface of the glass ribbon along a predetermined scan path and (2) the positioning beam relative to the position sensing means wherein the beams of light are synchronously displaced at a predetermined constant speed; sensing the intensity of the scanning beam of light with a photo detector as the scanning beam of light is moved with respect to the glass ribbon to determine defects in the glass ribbon along the scan path wherein defects in the glass ribbon along the scan path vary the intensity of the scanning beam of light; and monitoring the position sensing means and the photo detector to determine the position of the scanning beam along the scan path to determine defects in the glass ribbon as a function of position in the glass ribbon.
Claim 2
Independent Claim
198 words
A method of determining defects in a glass ribbon as a function of position in the glass ribbon, comprising the steps of: directing a first beam of light toward a first surface of the glass ribbon as a scanning beam of light; directing a second beam of light toward position sensing means as a positioning beam of light; synchronously displacing (1) the scanning beam of light relative to the surface of the glass ribbon along a predetermined scan path and (2) the positioning beam relative to the position sensing means wherein the beams of light are synchronously displaced at a predetermined constant speed; sensing the intensity of the scanning beam of light with a photo detector as the scanning beam of light is moved with respect to the glass ribbon to determine defects in the glass ribbon along the scan path wherein defects in the glass ribbon along the scan path vary the intensity of the scanning beam of light; and monitoring the position sensing means and the photo detector to determine the position of the scanning beam along the scan path to determine defects in the glass ribbon as a function of position in the glass ribbon.
Claim 3
Dependent Claim
109 words
The method as set forth in claim 1 wherein said synchronously displacing step is accomplished by: transmitting the scanning beam of light and positioning beam of light toward a reflecting means positioned at the focal point of a concave specular surface to reflect the beams of light toward the concave specular surface; oscillating the reflecting means at a predetermined constant speed to synchronously displace the beams of light along the specular surface to reflect the scanning beam of light from the specular surface to scan a portion of the glass ribbon along the scan path and to transmit the positioning beam toward and relative to the position sensing means.
Claim 4
Dependent Claim
49 words
The method as set forth in claim 1 further including the step of: displacing the glass ribbon and scanning beam relative to one another at a predetermined constant speed in a direction generally transverse to the scan path to scan contiguous lateral portions of the glass ribbon for defects.
Claim 5
Dependent Claim
31 words
The method as set forth in claim 1 wherein the scanning beam passes through the glass ribbon and is incident on the photo detector to sense intensity of the scanning beam.
Claim 6
Dependent Claim
52 words
The method as set forth in claim 1 wherein the scanning beam is incident on the surface of the glass ribbon and is reflected from at least one surface of the glass ribbon and the reflected scanning beam is incident on the photo detector to sense intensity of the reflected scanning beam.
Claim 7
Independent Claim
276 words
A method of determining defects in a glass ribbon as a function of position in the glass ribbon, comprising the steps of: directing a beam of light toward expanding means; expanding the light beam into a positioning beam of light and a scanning beam of light; directing the scanning beam and the positioning beam toward reflecting means positioned at a focal point of a concave specular surface to reflect the scanning beam from the reflecting means to the specular surface and to reflect the positioning beam from the reflecting means to the specular surface; transmitting the scanning beam from the specular surface through the glass ribbon onto a photo detector positioned at a second focal point of the concave specular surface and the positioning beam from the specular surface to position sensing means; oscillating the reflecting means at a predetermined constant speed to synchronously displace the scanning beam and positioning beam across the specular surface such that (1) the scanning beam scans a portion of the glass ribbon along a scan path and the positioning beam is displaced relative to the position sensing means; displacing the glass ribbon relative to the scanning beam at a constant predetermined speed in a direction generally transverse to the scan path to scan contiguous lateral portions of the glass ribbon; sensing the intensity of the scanning beam passed through the ribbon by the photo detector wherein intensity variations of the scanning beam passed through the riBbon are indicative of defects in the glass ribbon; and monitoring the position sensing means and the photo detector to determine defects in the glass ribbon as a function of position in the glass ribbon.
Claim 8
Independent Claim
276 words
A method of determining defects in a glass ribbon as a function of position in the glass ribbon, comprising the steps of: directing a beam of light toward expanding means; expanding the light beam into a positioning beam of light and a scanning beam of light; directing the scanning beam and the positioning beam toward reflecting means positioned at a focal point of a concave specular surface to reflect the scanning beam from the reflecting means to the specular surface and to reflect the positioning beam from the reflecting means to the specular surface; transmitting the scanning beam from the specular surface through the glass ribbon onto a photo detector positioned at a second focal point of the concave specular surface and the positioning beam from the specular surface to position sensing means; oscillating the reflecting means at a predetermined constant speed to synchronously displace the scanning beam and positioning beam across the specular surface such that (1) the scanning beam scans a portion of the glass ribbon along a scan path and the positioning beam is displaced relative to the position sensing means; displacing the glass ribbon relative to the scanning beam at a constant predetermined speed in a direction generally transverse to the scan path to scan contiguous lateral portions of the glass ribbon; sensing the intensity of the scanning beam passed through the ribbon by the photo detector wherein intensity variations of the scanning beam passed through the riBbon are indicative of defects in the glass ribbon; and monitoring the position sensing means and the photo detector to determine defects in the glass ribbon as a function of position in the glass ribbon.
Claim 9
Independent Claim
168 words
An apparatus for determining defects in a glass ribbon as a function of position in the glass ribbon comprising: means for detecting defects in the glass ribbon; means for directing a scanning beam of light toward the glass ribbon and from the glass ribbon onto said detecting means; means for sensing movement of a beam of light; means for directing a positioning beam of light toward said movement sensing means; means for synchronously displacing the positioning beam and scanning beam at a predetermined constant speed to displace the scanning beam of light relative to the surface of the glass ribbon along a predetermined scan path incident on said detecting means and to displace the positioning beam of light relative to said movement sensing means; and means acted on by said detecting means and said movement sensing means for indicating the intensity and the position of the scanning beam along the scan path to determine defects in the glass ribbon as a function of position in the glass ribbon.
Claim 10
Independent Claim
168 words
An apparatus for determining defects in a glass ribbon as a function of position in the glass ribbon comprising: means for detecting defects in the glass ribbon; means for directing a scanning beam of light toward the glass ribbon and from the glass ribbon onto said detecting means; means for sensing movement of a beam of light; means for directing a positioning beam of light toward said movement sensing means; means for synchronously displacing the positioning beam and scanning beam at a predetermined constant speed to displace the scanning beam of light relative to the surface of the glass ribbon along a predetermined scan path incident on said detecting means and to displace the positioning beam of light relative to said movement sensing means; and means acted on by said detecting means and said movement sensing means for indicating the intensity and the position of the scanning beam along the scan path to determine defects in the glass ribbon as a function of position in the glass ribbon.
Claim 11
Dependent Claim
41 words
The apparatus as set forth in claim 7 further including: means for displacing the scanning beam of light and glass ribbon relative to one another at a predetermined constant speed to scan contiguous lateral portions of the glass ribbon for defects.
Claim 12
Dependent Claim
102 words
The apparatus as set forth in claim 7 wherein said means for synchronously displacing the positioning beam and scanning beam comprises: a concave specular surface; and an oscillating mirror means mounted at the focal point of said concave specular surface and in the path of the scanning beam and positioning beam to synchronously displace the scanning beam and positioning beam along the surface of said concave specular surface wherein the scanning beam is reflected from said specular surface to the glass ribbon along the scan path and the positioning beam is reflected from said specular surface relative to said movement sensing means.
Claim 13
Dependent Claim
72 words
The apparatus as set forth in claim 7 wherein said means for sensing movement of the positioning beam includes: a first light responsive device actuated by the positioning beam at the start of a scanning cycle; and a second light responsive device actuated by the positioning beam at selected intervals as the scanning beam moves along a scan path wherein a selected interval corresponds to a selected portion of the scan path.
Claim 14
Dependent Claim
82 words
The apparatus as set forth in claim 10 further including: a fresnell lens having light-absorbing and light-passing areas spaced a predetermined distance apart along the surface of said fresnell lens in the path of the positioning beam; said first light responsive device selectively mounted on said fresnell lens; and said second light responsive device selectively mounted at the focal point of said fresnell lens such that the positioning beam passing through the light-passing areas is incident on said second light responsive device.
Claim 15
Dependent Claim
105 words
The apparatus as set forth in claim 10 including: a plurality of optical fiber bundles having a first end spaced a predetermined distance apart and in the path of the positioning beam and the second end of at least one bundle connected to said first responsive device to actuate said first responsive device when the positioning beam is incident on the first end of the respective bundle and the second end of the remaining optical fiber bundles connected to said second light responsive device to actuate said second light responsive device when the positioning beam is incident on the first end of the respective bundles.
Claim 16
Dependent Claim
59 words
The apparatus as set forth in claim 7 wherein said means for directing the scanning beam is on one side of a major surface of the glass ribbon to transmit the scanning beam through the glass ribbon as a transmitted scanninG beam, further including: means for mounting said defect detecting means in the path of the transmitted scanning beam.
Claim 17
Dependent Claim
58 words
The apparatus as set forth in claim 7 wherein said means for directing the scanning beam is on one side of a major surface of the glass to reflect the scanning beam from the major surface as a reflected scanning beam, further including: means for mounting said defect detecting means in the path of the reflected scanning beam.
Claim 18
Independent Claim
443 words
An apparatus for determining defects in a glass ribbon as a function of position in the glass ribbon wherein the glass ribbon has a first major surface and a second major surface opposite to the first major surface, comprising: a concave specular surface mounted adjacent the first side of the glass ribbon, said concave specular surface having a first focal point adjacent the first side of the glass ribbon and a second focal point adjacent the second side of the glass ribbon; a reflecting surface mounted at the first focal point of said specular surface; a light intensity detector mounted at the second focal point of said specular surface; position sensing means mounted in spaced relation to said specular surface, said position sensing means comprising: a fresnell lens having light absorbing areas and light-passing areas spaced a predetermined distance apart along the surface of said fresnell lens; a first response device mounted at one end of said fresnell lens said first response device activated at the start of a scan cycle; and a second light response device selectively mounted at the focal point of said fresnell lens; means for expanding light; means for directing a collimated beam of light toward said expanding means to expand the beam of light into a scanning beam of light and a positioning beam of light and for transmitting the positioning beam of light and scanning beam of light onto said reflecting surface to reflect the scanning beam of light and positioning beam of light onto said concave specular surface wherein the scanning beam of light is transmitted from said specular surface through the glass ribbon incident on said light intensity detector; means mounted in spaced relation to said specular surface and said position sensing means on the first side of the glass ribbon to reflect the positioning beam of light reflected from said specular surface to said position sensing means; means for oscillating said reflecting surface at a predetermined constant speed to synchronously displace the positioning beam and scanning beam along said specular surface to scan a portion of the glass ribbon along a scan path and to displace the positioning beam relative to said position sensing means to indicate the start of a scan cycle and the position of the scanning beam along the scan path; means for displacing the glass ribbon relative to the scanning beam in a direction generally transverse to the scan path to scan contiguous lateral portions of the glass ribbon; and means acted on by said position sensing means and said light intensity detector to determine the defects in the glass ribbon as a function of position in the glass ribbon.
Claim 19
Independent Claim
443 words
An apparatus for determining defects in a glass ribbon as a function of position in the glass ribbon wherein the glass ribbon has a first major surface and a second major surface opposite to the first major surface, comprising: a concave specular surface mounted adjacent the first side of the glass ribbon, said concave specular surface having a first focal point adjacent the first side of the glass ribbon and a second focal point adjacent the second side of the glass ribbon; a reflecting surface mounted at the first focal point of said specular surface; a light intensity detector mounted at the second focal point of said specular surface; position sensing means mounted in spaced relation to said specular surface, said position sensing means comprising: a fresnell lens having light absorbing areas and light-passing areas spaced a predetermined distance apart along the surface of said fresnell lens; a first response device mounted at one end of said fresnell lens said first response device activated at the start of a scan cycle; and a second light response device selectively mounted at the focal point of said fresnell lens; means for expanding light; means for directing a collimated beam of light toward said expanding means to expand the beam of light into a scanning beam of light and a positioning beam of light and for transmitting the positioning beam of light and scanning beam of light onto said reflecting surface to reflect the scanning beam of light and positioning beam of light onto said concave specular surface wherein the scanning beam of light is transmitted from said specular surface through the glass ribbon incident on said light intensity detector; means mounted in spaced relation to said specular surface and said position sensing means on the first side of the glass ribbon to reflect the positioning beam of light reflected from said specular surface to said position sensing means; means for oscillating said reflecting surface at a predetermined constant speed to synchronously displace the positioning beam and scanning beam along said specular surface to scan a portion of the glass ribbon along a scan path and to displace the positioning beam relative to said position sensing means to indicate the start of a scan cycle and the position of the scanning beam along the scan path; means for displacing the glass ribbon relative to the scanning beam in a direction generally transverse to the scan path to scan contiguous lateral portions of the glass ribbon; and means acted on by said position sensing means and said light intensity detector to determine the defects in the glass ribbon as a function of position in the glass ribbon.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-17 | 1978-09-16 | 1979-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-17 | 1982-09-16 | 1983-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-17 | 1986-09-16 | 1987-03-18 | $7700.00 | Window Closed / Lapsed |