US4553818A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Directional filter for filtering ambient light
Assignee: Honeywell International Inc
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Filing: 1983-12-12
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Granted: 1985-11-19
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Expires: 2003-12-12
Abstract
Abstract A directional filter for ambient light is constructed from a thin base strip (2) of indeterminate length and having an opaque surface (4). The strip is wound into a roll (8) having a plurality of convolutions (10) and sections (12, 14, 16 and 18) are cut from the face of the roll. A pair of sections are disposed so that their convolutions are in an orthogonal configuration, and are sandwiched between a pair of glass plates (20, 22) having non-reflective outside surfaces (20A). Channels (24) are thereby provided, which impart directional characteristics to the ambient light.
Inventors
- 👤 Richard L. Cohen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:03
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/86; H01J29/89; H01J29/896; G; G02; G02B; G02B27/00; G02B27/01; G02B27/0101; G02B5/00; G02B6/00; G02B6/04; G02B6/06; G02B6/08; G02B2027/0118
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
114 words
A directional filter for filtering ambient light, characterized by: first and second sections of a roll formed by winding a thin base strip into a plurality of convolutions, with each of the convolutions having an opaque surface: the first and second sections being cut from the face of the roll, with said first and second sections being disposed relative to each other so that their respective convolutions are in an orthogonal relationship; said convolutions in an orthogonal relationship cooperating to form light directing channels which are bounded by opaque surfaces: and said light directing channels imparting directional characteristics to light entering the filter from outside a predetermined angle and for thereby filtering said light.
Claim 2
Dependent Claim
114 words
A directional filter for filtering ambient light, characterized by: first and second sections of a roll formed by winding a thin base strip into a plurality of convolutions, with each of the convolutions having an opaque surface: the first and second sections being cut from the face of the roll, with said first and second sections being disposed relative to each other so that their respective convolutions are in an orthogonal relationship; said convolutions in an orthogonal relationship cooperating to form light directing channels which are bounded by opaque surfaces: and said light directing channels imparting directional characteristics to light entering the filter from outside a predetermined angle and for thereby filtering said light.
Claim 3
Dependent Claim
64 words
A filter as described by claim 1, characterized by: first and second cover plates; the first and second sections disposed relative to each other so that their respective convolutions are in an orthogonal relationship being sandwiched between the first and second cover plates; and the first and second sections and the first and second cover plates being bonded together to provide an integral filter.
Claim 4
Dependent Claim
30 words
A filter as described by claim 2, characterized in that: the first and second cover plates are of glass and the outside surface of each of the plates is non-reflective.
Claim 5
Dependent Claim
35 words
A filter as described by claim 1, characterized in that: the thin base strip is an acetate film; and the opaque surface on the base strip is a processed unexposed emulsion on said acetate film.
Claim 6
Dependent Claim
44 words
A filter as described by claim 1, characterized in that: the width of the predetermined angle varies inversely with the width of the base strip so that the directional characteristics of ambient light entering the filter are commensurate with the width of the strip.
Claim 7
Dependent Claim
39 words
A filter as described by claim 1, characterized by: the indices of refraction of the base strip and the opaque surface thereof are substantially the same so as to minimize secondary light reflection from the surfaces of the strip.
Claim 8
Dependent Claim
38 words
A filter as described by claim 1, characterized in that: the width of the thin base strip is t; the thickness of the opaque surface is f; and the light transmission characteristic of the filter corresponds to (t-f/t).
Claim 9
Dependent Claim
28 words
A filter as described by claim 1, characterized in that: the thin base strip is a polyester film; and the opaque surface is applied to the polyester film.
Claim 10
Dependent Claim
106 words
A directional filter for filtering ambient light, characterized by: first and second sections of a roll having a plurality of convolutions, each of the convolutions having an opaque surface; the first and second sections being cut from the face of the roll, with said first and second sections being disposed relative to each other so that their respective convolutions are in an orthogonal relationship; said convolutions in an orthogonal relationship cooperating to form light directing channels which are bounded by opaque surfaces; and said light directing channels imparting directional characteristics to light entering the filter from outside a predetermined angle and for thereby filtering said light.
Claim 11
Dependent Claim
106 words
A directional filter for filtering ambient light, characterized by: first and second sections of a roll having a plurality of convolutions, each of the convolutions having an opaque surface; the first and second sections being cut from the face of the roll, with said first and second sections being disposed relative to each other so that their respective convolutions are in an orthogonal relationship; said convolutions in an orthogonal relationship cooperating to form light directing channels which are bounded by opaque surfaces; and said light directing channels imparting directional characteristics to light entering the filter from outside a predetermined angle and for thereby filtering said light.
Claim 12
Dependent Claim
64 words
A filter as described by claim 10, characterized by: first and second cover plates; the first and second sections disposed relative to each other so that their respective convolutions are in an orthogonal relationship being sandwiched between the first and second cover plates; and the first and second sections and the first and second cover plates being bonded together to provide an integral filter.
Claim 13
Dependent Claim
30 words
A filter as described by claim 10, characterized in that: the first and second cover plates are of glass and the outside surface of each of the plates is non-reflective.
References Cited (Backward Citations)
US2053173A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-11-18 | 1989-05-20 | 1989-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-11-18 | 1993-05-20 | 1993-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-11-18 | 1997-05-20 | 1997-11-19 | $7700.00 | Window Closed / Lapsed |