Patent US4824208A successfully refreshed from Google Patents.
US4824208A
Expired / Lapsed
US
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Display for contrast enhancement
Assignee: Raychem Corp
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Filing: 1987-10-05
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Granted: 1989-04-25
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Expires: 2007-10-05
Abstract
Abstract A display comprising optical means for presenting an absence of light over a controlled viewing angle and means for selectively scattering or transmitting light in response to a prescribed input to effect a display of information within said viewing angle.
Inventors
- 👤 James L. Fergason
- 👤 Robert Parker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:15
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1334; G02F1/1335; G02F1/133526; G02F1/137; G02F1/13756
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
85 words
An apparatus for reducing glare comprising a light absorbing target and a concave reflector means for focusing specular reflection onto said target, said reflector means having a radius of curvature R and said target located on a viewing side of said reflector at a distance of between 0.4R and 0.5R therefrom and said target comprising vertically and horizontally extending light absorbing surfaces wherein the height of said vertically extending surface is approximately 0.0625R and the length of said horizontally extending surface is at least 0.1R.
Claim 2
Independent Claim
85 words
An apparatus for reducing glare comprising a light absorbing target and a concave reflector means for focusing specular reflection onto said target, said reflector means having a radius of curvature R and said target located on a viewing side of said reflector at a distance of between 0.4R and 0.5R therefrom and said target comprising vertically and horizontally extending light absorbing surfaces wherein the height of said vertically extending surface is approximately 0.0625R and the length of said horizontally extending surface is at least 0.1R.
Claim 3
Dependent Claim
19 words
The display of claim 1 wherein said target is located at a distance of 0.469R from said reflector means.
Claim 4
Independent Claim
77 words
A method for reducing glare from a display comprising focusing specular reflection from a concave reflecting surface having a radius of curvature R onto a light absorbing target means having vertically and horizontally extending light absorbing surfaces and located in front of said concave reflecting surface at a distance of between 0.4R and 0.5R wherein the height of said vertically extending surface is approximately 0.0625R and the length of said horizontally extending surface is at least 0.1R.
Claim 5
Independent Claim
77 words
A method for reducing glare from a display comprising focusing specular reflection from a concave reflecting surface having a radius of curvature R onto a light absorbing target means having vertically and horizontally extending light absorbing surfaces and located in front of said concave reflecting surface at a distance of between 0.4R and 0.5R wherein the height of said vertically extending surface is approximately 0.0625R and the length of said horizontally extending surface is at least 0.1R.
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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) | 1992-04-24 | 1992-10-24 | 1993-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-24 | 1996-10-24 | 1997-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-24 | 2000-10-24 | 2001-04-25 | $7700.00 | Window Closed / Lapsed |