Claims
- 1. An apparatus for measuring the width of a portion of a travelling web, said apparatus comprising:
- (a) illumination means for uniformly illuminating a transverse surface of said travelling web with diffuse light at a first angle to produce first reflections from a first portion of said surface coated with a coating material and second reflections from a second, non-coated portion of said surface, said first and second portions being transverse to the direction of travel of said web;
- (b) detector means positioned at a second angle for receiving said first and second reflections from the surface of said travelling web, and for producing signals indicative of the intensities of said first and second reflections as a function of the transverse distance across said web; and
- (c) processing means connected to said detector means for receiving said signals and for determining the width of at least one of said first portion or said second portion of said surface of said travelling web based on differences in light intensity between said first and second reflections.
- 2. An apparatus as claimed in claim 1, further comprising means for directing said first reflections to said detector means.
- 3. An apparatus as claimed in claim 1, wherein said first and second angles are approximately equal such that said first reflections include a predominantly specular component and said first and second angles are each about 45.degree. to 90.degree. from an axis normal to said travelling web.
- 4. An apparatus as claimed in claim 3, wherein said first and second angles are at least approximately equal and about 70.degree. to 90.degree. from an axis normal to said travelling web.
- 5. An apparatus as claimed in claim 1, wherein said first angle is less than 45.degree. and said second angle is between 70.degree.-90.degree..
- 6. An apparatus as claimed in claim 1, wherein said first angle is between 0.degree.-20.degree. and said second angle is between 70.degree.-90.degree..
- 7. An apparatus as claimed in claim 1, wherein said first angle is between 0.degree.-40.degree. and said second angle is between 50.degree.-90.degree..
- 8. An apparatus as claimed in claim 1, wherein said first angle is between 50.degree.-90.degree. and said
- 9. An apparatus as claimed in claim 1, wherein said first angle is between 70.degree.-90.degree. and said second angle is between 0.degree.-20.degree..
- 10. An apparatus as claimed in claim 1, further including a polarizing filter disposed between said web and said detector.
- 11. An apparatus as claimed in claim 10, wherein said first and second angles are each approximately equal to Brewster's angle.
- 12. A method of measuring the width of a portion of a surface of a travelling web, said method comprising the steps of:
- (a) uniformly illuminating said surface of said travelling web with diffuse light at a first angle to produce first reflections from a first portion of said surface coated with said coating material and second reflections from a second, non-coated portion of said surface, said first and second portions being transverse to the direction of transverse of said web;
- (b) receiving at a second angle said first and second reflections from the surface of said travelling web;
- (c) generating signals indicative of the intensities of said first and second reflections as a function of the transverse distance across said web; and
- (d) determining the width of at least one of said first and second portions based on differences in light intensity between said first and second reflections.
- 13. A method of detecting the presence of a coating material on a surface of a travelling web as claimed in claim 12, wherein said first and second angles are at least approximately equal and are about 45.degree. to 90.degree. from an axis normal to said travelling web.
- 14. A method of detecting the presence of a coating material on a surface of a travelling web as claimed in claim 13, wherein said first and second angles are at least approximately equal and are about 70.degree. to 90.degree. from an axis normal to said travelling web.
- 15. A method as claimed in claim 12, wherein said first angle is less than 45.degree. and said second angle is between 70.degree.-90.degree..
- 16. A method as claimed in claim 12, wherein said first angle is between 0.degree.-20.degree. and said second angle is between 70.degree.-90.degree..
- 17. A method as claimed in claim 12, wherein said first angle is between 0.degree.-40.degree. and said second angle is between 50.degree.-90.degree..
- 18. A method as claimed in claim 12, wherein said first angle is between 50.degree.-90.degree. and said second angle is between 0.degree.-40.degree..
- 19. A method as claimed in claim 12, wherein said first angle is between 70.degree.-90.degree. and said second angle is between 0.degree.-20.degree..
- 20. An apparatus for measuring the width of a travelling web, said apparatus comprising:
- (a) illumination means for uniformly illuminating a surface of said web with diffuse light at a first angle to produce first reflections from a first portion of said surface having a relatively smooth material thereon and second reflections from a second portion of said surface not having said relatively smooth material thereon, said first and second portions being transverse to the direction of travel of said web;
- (b) detector means positioned at a second angle for receiving said first and second reflections from the surface of said web, and for producing signals indicative of the intensities of said first and second reflections as a function of the transverse distance across said web; and
- (c) processing means connected to said detector means for receiving said signals and for determining the width of at least one of said first portion or said second portion of said surface of said web based on differences in light intensity between said first and second reflections.
- 21. A method of measuring the width of a portion of a surface of a travelling web, said method comprising the steps of:
- (a) uniformly illuminating said surface of said web with diffuse light at a first angle to produce first reflections from a first portion of said surface having a relatively smooth material thereon and second reflections from a second portion of said surface not having said relatively smooth material thereon, said first and second portions being transverse to the direction of travel of said web;
- (b) receiving said first and second reflections from the surface of said web at a second angle;
- (c) generating signals indicative of the intensities of said first and second reflections as a function of the transverse distance across said web; and
- (d) determining the width of at least one of the first and second portions based on the differences in light intensity between said first and second reflections.
- 22. A method of measuring the width of a portion of a travelling web comprising the steps of:
- (a) illuminating, at an angle of incidence, said surface of said travelling web with a diffuse light source to produce first reflections from a first portion of said surface coated with said coating material and second reflections from a second portion of said surface not coated with said coating material, said first reflections having a first light intensity when observed at an angle of observation substantially equal to said angle of incidence, and a second intensity when observed at an angle of observation not substantially equal to said angle of incidence, said second reflections having a range of third light intensities intermediate said first and second light intensities, said first and second portions being transverse to the direction of transverse of said web;
- (b) positioning a light detector at an angle of observation for receiving said first and second reflections;
- (c) generating signals indicative of the intensities of said first and second reflections as a function of the transverse distance across said web; and
- (d) responsive to said signals, automatically determining the width of at least one of said first and second portions based on the difference in light intensities between at least two of said first, second and third intensities.
- 23. A method as recited in claim 22, further comprising the step of determining the width of said first portion.
- 24. A method as recited in claim 23, wherein said angle of incidence is between about 70.degree. to 90.degree. as measured from an axis normal to said travelling web.
- 25. A method as recited in claim 23, wherein said angle of incidence is between about 45.degree. to 90.degree. as measured from axis normal to said travelling web.
- 26. A method as recited in claim 22, wherein said angle of incidence is less than 45.degree. and said angle of observation is between 70.degree.-90.degree..
- 27. A method as recited in claim 22, wherein said angle of incidence is between 0.degree.-20.degree. and said angle of observation is between 70.degree.-90.degree..
- 28. A method as recited in claim 22, wherein said angle of incidence is between 0.degree.-40.degree. and said angle of observation is between 50.degree.-90.degree..
- 29. A method as recited in claim 22, wherein said angle of incidence is between 50.degree.-90.degree. and said angle of observation is between 0.degree.-40.degree..
- 30. A method as recited in claim 22, wherein said angle of incidence is between 70.degree.-90.degree. and said angle of observation is between 0.degree.-20.degree..
- 31. Apparatus for measuring the width of a portion of a surface of a travelling web comprising:
- (a) means for illuminating, at an angle of incidence, said surface of said travelling web with a diffuse light source to produce first reflections from a first portion of said surface coated with said coating material and second reflections from a second portion of said surface not coated with said coating material, said first reflections having a first light intensity when observed at an angle of observation substantially equal to said angle of incidence, and a second intensity when observed at an angle of observation not substantially equal to said angle of incidence, said second reflections having a range of third light intensities intermediate said first and second light intensities, said first and second portions being transverse to the direction of travel of said web;
- (b) light detector means for receiving, at an angle of observation, said first and second reflections, and for producing signals indicative of the intensities of said first and second reflections as a function of the transverse distance across said web;
- (c) means responsive to said signals for automatically determining the width of at least one of said first and second portions based on the differences in light intensity between at least two of said first, second and third intensities.
- 32. Apparatus for detecting the presence of a coating material on a travelling web comprising:
- (a) illumination means for uniformly illuminating a surface of said travelling web with diffuse light at a first angle;
- (b) said web having a first portion of said surface having said coating material thereon and a second, discrete portion not having said coating material thereon;
- (c) said illumination means producing first reflections from said first, coated portion of said web and second reflections from said second, non-coated portion of said web;
- (d) detector means positioned at a second angle for receiving said first and second reflections from the surface of said travelling web; and
- (e) processing means, connected to said detector means, for separately determining the light intensity of said first and second reflections and for detecting the presence of said coating material on said first portion of said travelling web based on differences in light intensity between said first and second reflections.
- 33. An apparatus as claimed in claim 32, wherein said processing means determines the width of said coating material based on the first reflections received by said detector means.
- 34. An apparatus as claimed in claim 32, further comprising means for directing said first reflections to said detector means.
- 35. An apparatus in claim 32, wherein said first and second angles are approximately equal such that said first reflections include a predominantly specular component and said first and second angles are each about 45.degree. to 90.degree. from an axis normal to said travelling web.
- 36. An apparatus as claimed in claim 35, wherein said first and second angles are at least approximately equal and about 70.degree. to 90.degree. from an axis normal to said travelling web.
- 37. An apparatus as claimed in claim 32, wherein said first angle is less than 45.degree. and said second angle is between 70.degree.-90.degree..
- 38. An apparatus as claimed in claim 32, wherein said first angle is between 0.degree.-20.degree. and said second angle is between 70.degree.-90.degree..
- 39. An apparatus as claimed in claim 32, wherein said first angle is between 0.degree.-40.degree. and said second angle is between 50.degree.-90.degree..
- 40. An apparatus as claimed in claim 32, wherein said first angle is between 50.degree.-90.degree. and said second angle is between 0.degree.-40.degree..
- 41. An apparatus as claimed in claim 32, wherein said first angle is between 70.degree.-90.degree. and said second angle is between 0.degree.-20.degree..
- 42. An apparatus as claimed in claim 32, further including a polarizing filter disposed between said web and said detector.
- 43. An apparatus as claimed in claim 42, wherein said first and second angles are each approximately equal to Brewster's angle.
- 44. A method of detecting the presence of a coating material on a surface of a travelling web, said method comprising the steps of:
- (a) uniformly illuminating said surface of said travelling web with a diffuse light source at a first angle;
- (b) providing said web with a first portion of said surface having said coating material thereon and a second, discrete portion not having said coating material thereon;
- (c) orienting said web and said diffuse light source for producing first reflections from said first portion of said web coated with said coating material and second reflections from said second, non-coated portion of said web;
- (d) receiving at a second angle said first and second reflections from the surface of said travelling web;
- (e) separately determining the light intensities of said first and second reflections; and
- (f) detecting the presence of said coating material on the first portion of said travelling web based on differences in light intensity between said first and second reflections.
- 45. A method of detecting the presence of a coating material on a surface of a travelling web as claimed in claim 44, further comprising the step of determining the width of said, coating material based on the first reflections.
- 46. A method of detecting the presence of a coating material on a surface of a travelling web as claimed in claim 44, wherein said first and second angles are at least approximately equal and are about 45.degree. to 90.degree. from an axis normal to said travelling web.
- 47. A method of detecting the presence of a coating material on a surface of a travelling web as claimed in claim 46, wherein said first and second angles are at least approximately equal and are about 70.degree. to 90.degree. from an axis normal to said travelling web.
- 48. A method as claimed in claim 44, wherein said first angle is less than 45.degree. and said second angle is between 70.degree.-90.degree..
- 49. A method as claimed in claim 44, wherein said first angle is between 0.degree.-20.degree. and said second angle is between 70.degree.-90.degree..
- 50. A method as claimed in claim 44, wherein said first angle is between 0.degree.-40.degree. and said second angle is between 50.degree.-90.degree..
- 51. A method as claimed in claim 44, wherein said first angle is between 50.degree.-90.degree. and said second angle is between 0.degree.-40.degree..
- 52. A method as claimed in claim 44, wherein said first angle is between 70.degree.-90.degree. and said second angle is between 0.degree.-20.degree..
CROSS REFERENCE TO RELATED APPLICATIONS
This is a continuation-in-part of U.S. application Ser. No. 075,506, filed July 20, 1987 now abandoned.
US Referenced Citations (13)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
75506 |
Jul 1987 |
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