Patent US4290473A successfully refreshed from Google Patents.
US4290473A
Expired / Lapsed
US
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Apparatus for controlling light transmission through a window
Assignee: Queen's University
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Filing: 1979-01-24
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Granted: 1981-09-22
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Expires: 1999-01-24
Abstract
Abstract A device for controlling light transmission through an opening in which a pair of spaced planar parallel films are placed adjacent an opening. The films are selected to have uniformly and linearly varying light transmitting characteristics and are designed to be moved relative to each other, generally in opposite directions, so that a substantially uniform degree of light transmission is achieved over the entire opening area. The films may be either absorptive or reflective and the films may be moved manually or electrically and automatically in response to a sensing and control device.
Inventors
- 👤 James G. Pierson
- 👤 David A. Wilmshurst
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 14:12
CPC Classifications
E; E06; E06B; E06B9/00; E06B9/24
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
148 words
A device for controlling transmission of light through a window comprising: (a) two lineal strips of roller-mounted film material having light transmission characteristics which vary linearly longitudinally from a maximum at one end to a minimum at the other end thereof, said strips being (i) disposed in overlying spaced parallel planar relationship over an area corresponding at least to the area of the window, (ii) extended beyond said area, and (iii) disposed so that said maximum transmission characteristic end of a first said strip is in juxtaposition with said minimum transmission characteristic end of a second said strip; and (b) means for linearly moving one film strip relative to the other in said overlying relationship and in said area, whereby the amount of light transmission over said area is dependent upon the relative light transmission characteristics of said two film strips and is substantially uniform over said area.
Claim 2
Independent Claim
148 words
A device for controlling transmission of light through a window comprising: (a) two lineal strips of roller-mounted film material having light transmission characteristics which vary linearly longitudinally from a maximum at one end to a minimum at the other end thereof, said strips being (i) disposed in overlying spaced parallel planar relationship over an area corresponding at least to the area of the window, (ii) extended beyond said area, and (iii) disposed so that said maximum transmission characteristic end of a first said strip is in juxtaposition with said minimum transmission characteristic end of a second said strip; and (b) means for linearly moving one film strip relative to the other in said overlying relationship and in said area, whereby the amount of light transmission over said area is dependent upon the relative light transmission characteristics of said two film strips and is substantially uniform over said area.
Claim 3
Dependent Claim
16 words
A device as claimed in claim 1, wherein said film material is a light absorptive film.
Claim 4
Dependent Claim
23 words
A device as claimed in claim 1 wherein said film material is coated with a layer of light reflective material of varying thickness.
Claim 5
Dependent Claim
20 words
A device as claimed in claim 1 wherein said film material is coated with a layer of an evaporated metal.
Claim 6
Dependent Claim
21 words
A device as claimed in claim 1 wherein said film material is coated with a layer of varying thickness of gold.
Claim 7
Dependent Claim
24 words
A device as claimed in claim 1 wherein said means for moving said strips includes means to move said strips linearly in opposite directions.
Claim 8
Dependent Claim
18 words
A device as claimed in claim 6 wherein said means for moving said strips is a power means.
Claim 9
Dependent Claim
24 words
A device as claimed in claim 7 including sensor means for actuating said power means in response to a signal indicative of light intensity.
Claim 10
Dependent Claim
17 words
A device as claimed in claim 6 including means to move both said films without slippage therebetween.
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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) | 1984-09-21 | 1985-03-23 | 1985-09-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-09-21 | 1989-03-23 | 1989-09-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-09-21 | 1993-03-23 | 1993-09-22 | $7700.00 | Window Closed / Lapsed |