Patent US3136053A successfully refreshed from Google Patents.
Patent US4946282A successfully refreshed from Google Patents.
US4946282A
Expired / Lapsed
US
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Transparency transmissivity measurement device
Assignee: United States Department of the Air Force
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Filing: 1988-11-18
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Granted: 1990-08-07
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Expires: 2008-11-18
Abstract
Abstract A device for measuring optical transmissivity of a transparency is described which comprises a diffuse light source (Lambertian diffuser) of controllable substantially constant luminance and preselected light emitting surface area for placement near a first side of a transparency for transmitting diffuse light along an optical axis through the transparency, a housing having a wall defining an aperture for placement near the second side of the transparency opposite the diffuse light source, and a detector in the form of a photo diode, cadmium sulfide cell or the like disposed within the housing and coaxial with and spaced a preselected distance from the aperture, the aperture being selected in size to expose all of the effective light detection surface area of said detector to the light emitting surface area of the diffuse light source.
Inventors
- 👤 Harry L. Task
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:48
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/59; G01N2201/00; G01N2201/06; G01N2201/061; G01N2201/06126
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
158 words
A device for measuring optical transmissivity of a transparency, comprising: (a) a diffuse light source of controllable substantially constant luminance and preselected light emitting surface area for placement near the surface defined by a first side of a transparency for transmission of diffuse light along an optical axis through said transparency in measuring the transmissivity thereof; (b) housing having a wall defining an aperture for placement near the surface defined by the second side of said transparency and substantially along said optical axis opposite said diffuse light source; (c) a detector having preselected effective light detection surface area disposed within said housing and coaxial with and spaced a preselected distance from said aperture; and (d) said aperture selected in diametric size smaller than said light emitting surface area of said diffuse light source whereby substantially all said effective light detection surface area of said detector is exposed to said light emitting surface area of said diffuse light source.
Claim 2
Independent Claim
158 words
A device for measuring optical transmissivity of a transparency, comprising: (a) a diffuse light source of controllable substantially constant luminance and preselected light emitting surface area for placement near the surface defined by a first side of a transparency for transmission of diffuse light along an optical axis through said transparency in measuring the transmissivity thereof; (b) housing having a wall defining an aperture for placement near the surface defined by the second side of said transparency and substantially along said optical axis opposite said diffuse light source; (c) a detector having preselected effective light detection surface area disposed within said housing and coaxial with and spaced a preselected distance from said aperture; and (d) said aperture selected in diametric size smaller than said light emitting surface area of said diffuse light source whereby substantially all said effective light detection surface area of said detector is exposed to said light emitting surface area of said diffuse light source.
Claim 3
Dependent Claim
20 words
The device of claim 1 wherein said diffuse light source includes a substantially white incandescent source and a Lambertian diffuser.
Claim 4
Dependent Claim
12 words
The device of claim 1 wherein said detector comprises a photo diode.
Claim 5
Dependent Claim
13 words
The device of claim 1 wherein said detector comprises a cadmium sulfide cell.
Claim 6
Dependent Claim
31 words
The device of claim 1 further comprising a lens at said aperture for collecting light transmitted along said optical axis through said transparency from said diffuse light source to said detector.
Claim 7
Dependent Claim
17 words
The device of claim 1 further comprising light shielding means for excluding extraneous light from said aperture.
Claim 8
Independent Claim
162 words
A device for measuring optical transmissivity of a transparency, comprising: (a) a diffuse light source of controllable substantially constant luminance and preselected light emitting surface area for placement near the surface defined by a first side of a transparency for transmission of diffuse light along an optical axis through said transparency in measuring the transmissivity thereof; (b) a housing having a wall defining an aperture for placement near the surface defined by the second side of said transparency and substantially along said optical axis opposite said diffuse light source, said aperture selected in diametric size smaller than said light emitting surface area of said diffuse light source; (c) a detector having preselected effective light detection surface area disposed within said housing and coaxial with and spaced a preselected distance from said aperture; and (d) a lens disposed near said aperture and coaxial therewith for collecting light transmitted along said optical axis through said transparency from said diffuse light source to said detector.
Claim 9
Independent Claim
162 words
A device for measuring optical transmissivity of a transparency, comprising: (a) a diffuse light source of controllable substantially constant luminance and preselected light emitting surface area for placement near the surface defined by a first side of a transparency for transmission of diffuse light along an optical axis through said transparency in measuring the transmissivity thereof; (b) a housing having a wall defining an aperture for placement near the surface defined by the second side of said transparency and substantially along said optical axis opposite said diffuse light source, said aperture selected in diametric size smaller than said light emitting surface area of said diffuse light source; (c) a detector having preselected effective light detection surface area disposed within said housing and coaxial with and spaced a preselected distance from said aperture; and (d) a lens disposed near said aperture and coaxial therewith for collecting light transmitted along said optical axis through said transparency from said diffuse light source to said detector.
Claim 10
Dependent Claim
20 words
The device of claim 7 wherein said diffuse light source includes a substantially white incandescent source and a Lambertian diffuser.
Claim 11
Dependent Claim
12 words
The device of claim 7 wherein said detector comprises a photo diode.
Claim 12
Dependent Claim
13 words
The device of claim 7 wherein said detector comprises a cadmium sulfide cell.
Claim 13
Dependent Claim
38 words
The device of claim 7 wherein said lens is positioned whereby the spacing between said diffuse light source and said lens with said transparency therebetween is substantially equal to or less than the focal length of said lens.
Claim 14
Dependent Claim
17 words
The device of claim 7 further comprising light shielding means for excluding extraneous light from said aperture.
Claim 15
Independent Claim
173 words
A device for measuring optical transmissivity of a transparency, comprising: (a) a substantially white incandescent light source of controllable intensity for projecting light along an optical axis through a transparency in measuring the transmissivity thereof; (b) a Lambertian diffuser disposed along said optical axis for placement near the surface defined by a first side of said transparency for diffusing light transmitted along said optical axis through said transparency in measuring the transmissivity thereof; (c) a housing having a wall defining an aperture for placement near the surface defined by the second side of said transparency and substantially along said optical axis opposite said diffuser, said aperture selected in diametric size smaller than the light emitting surface area of said diffuser; (d) a detector having preselected effective light detection surface area disposed within said housing and coaxial with and spaced a preselected distance from said aperture; and (e) said aperture selected in size to expose said effective light detection surface area of said detector to light transmitted along said optical axis from said diffuser.
Claim 16
Independent Claim
173 words
A device for measuring optical transmissivity of a transparency, comprising: (a) a substantially white incandescent light source of controllable intensity for projecting light along an optical axis through a transparency in measuring the transmissivity thereof; (b) a Lambertian diffuser disposed along said optical axis for placement near the surface defined by a first side of said transparency for diffusing light transmitted along said optical axis through said transparency in measuring the transmissivity thereof; (c) a housing having a wall defining an aperture for placement near the surface defined by the second side of said transparency and substantially along said optical axis opposite said diffuser, said aperture selected in diametric size smaller than the light emitting surface area of said diffuser; (d) a detector having preselected effective light detection surface area disposed within said housing and coaxial with and spaced a preselected distance from said aperture; and (e) said aperture selected in size to expose said effective light detection surface area of said detector to light transmitted along said optical axis from said diffuser.
Claim 17
Dependent Claim
12 words
The device of claim 13 wherein said detector is a photo diode.
Claim 18
Dependent Claim
13 words
The device of claim 13 wherein said detector is a cadmium sulfide cell.
Claim 19
Dependent Claim
17 words
The device of claim 13 further comprising light shielding means for excluding extraneous light from said aperture.
Claim 20
Independent Claim
175 words
A device for measuring optical transmissivity of a transparency, comprising: (a) a substantially white incandescent light source of controllable intensity for projecting light along an optical axis through a transparency in measuring the transmissivity thereof; (b) a Lambertian diffuser disposed along said optical axis for placement near the surface defined by a first side of said transparency for diffusing light transmitted along said optical axis through said transparency in measuring the transmissivity thereof; (c) a housing having a wall defining an aperture for placement near the surface defined by the second side of said transparency and substantially along said optical axis opposite said diffuser, said aperture selected in diametric size smaller than the light emitting surface area of said diffuser; (d) a detector having preselected effective light detection surface area disposed within said housing and coaxial with and spaced a preselected distance from said aperture; and (e) a lens disposed near said aperture and coaxial therewith for collecting light transmitted along said optical axis through said transparency from said diffuse light source to said detector.
Claim 21
Independent Claim
175 words
A device for measuring optical transmissivity of a transparency, comprising: (a) a substantially white incandescent light source of controllable intensity for projecting light along an optical axis through a transparency in measuring the transmissivity thereof; (b) a Lambertian diffuser disposed along said optical axis for placement near the surface defined by a first side of said transparency for diffusing light transmitted along said optical axis through said transparency in measuring the transmissivity thereof; (c) a housing having a wall defining an aperture for placement near the surface defined by the second side of said transparency and substantially along said optical axis opposite said diffuser, said aperture selected in diametric size smaller than the light emitting surface area of said diffuser; (d) a detector having preselected effective light detection surface area disposed within said housing and coaxial with and spaced a preselected distance from said aperture; and (e) a lens disposed near said aperture and coaxial therewith for collecting light transmitted along said optical axis through said transparency from said diffuse light source to said detector.
Claim 22
Dependent Claim
12 words
The device of claim 17 wherein said detector comprises a photo diode.
Claim 23
Dependent Claim
13 words
The device of claim 17 wherein said detector comprises a cadmium sulfide cell.
Claim 24
Dependent Claim
38 words
The device of claim 17 wherein said lens is positioned whereby the spacing between said diffuse light source and said lens with said transparency therebetween is substantially equal to or less than the focal length of said lens.
Claim 25
Dependent Claim
17 words
The device of claim 17 further comprising light shielding means for excluding extraneous light from said aperture.
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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) | 1993-08-06 | 1994-02-05 | 1994-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-06 | 1998-02-05 | 1998-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-06 | 2002-02-05 | 2002-08-07 | $7700.00 | Window Closed / Lapsed |