US4185895A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reflective mode, dynamic scattering liquid crystal display system having a Fresnel reflector for lighting
Assignee: Raytheon Co
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Filing: 1978-03-31
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Granted: 1980-01-29
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Expires: 1998-03-31
Abstract
Abstract Light is directed at a liquid crystal display with the aid of a Fresnel mirror. With the liquid crystal display upright, the mirror is placed in front of, and slightly below it, so that light from overhead is reflected at the display by the mirror's facets.
Inventors
- 👤 Craig P. Stephens
- 👤 Andrew G. Toth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:09
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/133553; G02F1/137; G02F1/13743; G02F1/1375; G02F1/13756
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
93 words
A display system comprising in combination: (a) a base having a support surface extending in a first plane; (b) a reflective mode, dynamic scattering, liquid crystal display mounted on said base and extending in a second plane transversely to said support surface; (c) a Fresnel reflector mounted on said support surface in front of said liquid crystal display and extending transversely therefrom, said reflector having a plurality of reflective facets disposed in a plurality of planes, each plane disposed at an acute included angle with the second plane of said liquid crystal display.
Claim 2
Dependent Claim
93 words
A display system comprising in combination: (a) a base having a support surface extending in a first plane; (b) a reflective mode, dynamic scattering, liquid crystal display mounted on said base and extending in a second plane transversely to said support surface; (c) a Fresnel reflector mounted on said support surface in front of said liquid crystal display and extending transversely therefrom, said reflector having a plurality of reflective facets disposed in a plurality of planes, each plane disposed at an acute included angle with the second plane of said liquid crystal display.
Claim 3
Dependent Claim
37 words
The display system of claim 1 characterized further in that said plurality of facets are disposed in a succession of parallel planes disposed at a common included angle with the second plane of said liquid crystal display.
Claim 4
Dependent Claim
20 words
The display system of claim 2 characterized further in that said common included angle is between 50° and 65° inclusive.
Claim 5
Dependent Claim
49 words
The display system of claim 3 characterized further by a light source fixed relative to said base in front of said liquid crystal display and above said Fresnel reflector, so that light from said source is reflected from the facets of said reflector obliquely at said liquid crystal display.
Claim 6
Dependent Claim
27 words
The display system of claim 3 characterized further in that said liquid crystal display is two-toned, and said common included angle is between 50° and 55° inclusive.
Claim 7
Dependent Claim
29 words
The display system of claim 3 characterized further in that said liquid crystal display has gray shade capability and said common included angle is between 55° and 65° inclusive.
Claim 8
Dependent Claim
54 words
The display system of claim 1 characterized further in that said plurality of facets are formed by a succession of concentric grooves and in that the planes in which successive ones of said facets lie form progressively smaller included angles with the second plane of said display at progressively greater distances from said display.
Claim 9
Dependent Claim
30 words
The display system of claim 7 characterized further in that said Fresnel reflector has a focal point which lies behind and above the display surface of said liquid crystal display.
Claim 10
Dependent Claim
88 words
In a display system having an upright reflective mode dynamic scattering liquid crystal display illuminated by an overhead light source, the improvement comprising: a Fresnel reflector mounted in front of and below said liquid crystal display and extending laterally therefrom, said reflector having a plurality of facets disposed in a plurality of planes, each plane disposed at an acute included angle with the display surface of said liquid crystal display, so that light from said overhead source impinging on said lens is reflected thereby at said display surface.
Claim 11
Dependent Claim
88 words
In a display system having an upright reflective mode dynamic scattering liquid crystal display illuminated by an overhead light source, the improvement comprising: a Fresnel reflector mounted in front of and below said liquid crystal display and extending laterally therefrom, said reflector having a plurality of facets disposed in a plurality of planes, each plane disposed at an acute included angle with the display surface of said liquid crystal display, so that light from said overhead source impinging on said lens is reflected thereby at said display surface.
Claim 12
Dependent Claim
37 words
The display system of claim 9 characterized further in that said plurality of facets are disposed in a succession of parallel planes disposed at a common included angle with the display surface of said liquid crystal display.
Claim 13
Dependent Claim
20 words
The display system of claim 10 characterized further in that said common included angle is between 50° and 65° inclusive.
Claim 14
Dependent Claim
50 words
The display system of claim 10 characterized further by a light source fixed relative to said base in front of said liquid crystal display and above said Fresnel reflector so that light from said source is reflected from the facets of said lens obliquely at said liquid crystal display surface.
Claim 15
Dependent Claim
27 words
The display system of claim 11 characterized further in that said liquid crystal display is two-toned and said common included angle is between 50° and 55° inclusive.
Claim 16
Dependent Claim
29 words
The display system of claim 11 characterized further in that said liquid crystal display has gray shade capability and said common included angle is between 55° and 65° inclusive.
Claim 17
Dependent Claim
54 words
The display system of claim 9 characterized further in that said plurality of facets are formed by a succession of concentric grooves and in that the planes in which successive ones of said facets lie form progressively smaller included angles with the second plane of said display at progressively greater distances from said display.
Claim 18
Dependent Claim
30 words
The display system of claim 15 characterized further in that said Fresnel reflector has a focal point which lies behind and above the display surface of said liquid crystal display.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-01-28 | 1983-07-30 | 1984-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-01-28 | 1987-07-30 | 1988-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-01-28 | 1991-07-30 | 1992-01-29 | $7700.00 | Window Closed / Lapsed |