US4516834A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Contrast enhanced liquid crystal display
Assignee: Boeing North American Inc
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Filing: 1983-04-08
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Granted: 1985-05-14
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Expires: 2003-04-08
Abstract
Abstract A contrast enhanced liquid crystal display is disclosed having two substantially identical liquid crystal displays with a transflector disposed in between such that light entering from the viewing surface of the first liquid crystal is attenuated twice by the dark areas of the first crystal, and light entering from the rear of the second crystal is attenuated twice, once by the rear liquid crystal and once by the front liquid crystal. This configuration provides an enhanced contrast for all viewing conditions ranging from bright sunlight to totally dark conditions wherein the contrast ratio is maintained relatively constant at between 9:1 and 11:1 when comparing the light areas of the display to the darkened areas when using single crystals each having a contrast ratio of between 4:1 and 4.5:1 in back lit conditions.
Inventors
- 👤 Michael R. Cascini
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:14
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1347; G02F1/1335; G02F2203/00; G02F2203/09
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
23 words
A liquid crystal display comprising two distinct liquid crystal displays in a spaced parallel relationship and having a transflector disposed interjacent said displays.
Claim 2
Dependent Claim
23 words
A liquid crystal display comprising two distinct liquid crystal displays in a spaced parallel relationship and having a transflector disposed interjacent said displays.
Claim 3
Dependent Claim
19 words
A display as in claim 1 further comprising means for illumination disposed adjacent one of said liquid crystal displays.
Claim 4
Dependent Claim
15 words
A display as in claim 1 wherein said two liquid crystal displays are substantially identical.
Claim 5
Dependent Claim
76 words
A liquid crystal display assembly comprising: a. a first liquid crystal display having a segmented configuration; b. a transflector disposed in a spaced parallel relationship with said first liquid crystal display; and c. a second distinct and separate liquid crystal display disposed adjacent said transflector and on an opposite side thereof relative to said first display, and said second display having segments formed substantially similar to, and aligned with, said segmented configuration of said first display.
Claim 6
Dependent Claim
76 words
A liquid crystal display assembly comprising: a. a first liquid crystal display having a segmented configuration; b. a transflector disposed in a spaced parallel relationship with said first liquid crystal display; and c. a second distinct and separate liquid crystal display disposed adjacent said transflector and on an opposite side thereof relative to said first display, and said second display having segments formed substantially similar to, and aligned with, said segmented configuration of said first display.
Claim 7
Dependent Claim
19 words
A display as in claim 4 further comprising means for illumination disposed adjacent one of said liquid crystal displays.
Claim 8
Dependent Claim
15 words
A display as in claim 5 wherein said means for illumination comprises an electroluminescent panel.
Claim 9
Dependent Claim
137 words
A contrast enhanced liquid crystal display comprising in combination: a. a first liquid crystal display having segments for selective annunciation and having a planar viewing surface thereon; b. a reflective surface additionally having a light transmission characteristic disposed in a separate and proximal parallel relationship to a surface of said first liquid crystal display opposite said viewing surface, said reflective surface for reflecting light received from said viewing surface back to said viewing surface; and c. a second liquid crystal display having a substantially similar segment configuraton to said first liquid crystal display and disposed in a proximal parallel relationship to said reflective surface and in alignment with said first liquid crystal display such that light from said second liquid crystal is transmitted through said reflective surface to said viewing surface of said first liquid crystal display.
Claim 10
Dependent Claim
137 words
A contrast enhanced liquid crystal display comprising in combination: a. a first liquid crystal display having segments for selective annunciation and having a planar viewing surface thereon; b. a reflective surface additionally having a light transmission characteristic disposed in a separate and proximal parallel relationship to a surface of said first liquid crystal display opposite said viewing surface, said reflective surface for reflecting light received from said viewing surface back to said viewing surface; and c. a second liquid crystal display having a substantially similar segment configuraton to said first liquid crystal display and disposed in a proximal parallel relationship to said reflective surface and in alignment with said first liquid crystal display such that light from said second liquid crystal is transmitted through said reflective surface to said viewing surface of said first liquid crystal display.
Claim 11
Dependent Claim
46 words
A contrast enhanced liquid crystal display as in claim 7 wherein said light from said second liquid crystal is provided by an electroluminescent panel disposed in a proximal parallel relationship adjacent said second liquid crystal and on an opposite side thereon relative to said reflective surface.
Claim 12
Dependent Claim
25 words
A contrast enhanced liquid crystal display as in claim 8 further comprising elastomeric connectors for electrical intercommunication of said first display with said second display.
Claim 13
Dependent Claim
46 words
A contrast enhanced liquid crystal display as in claim 9 further comprising a printed circuit board for electrical interconnection of said first and second liquid crystal displays wherein all of said components have a fixed relative position to said printed circuit board and to each other.
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) | 1988-05-13 | 1988-11-12 | 1989-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-13 | 1992-11-12 | 1993-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-13 | 1996-11-12 | 1997-05-14 | $7700.00 | Window Closed / Lapsed |