US4998804A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transmissive liquid crystal display device
Assignee: Sharp Corp
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Filing: 1989-06-05
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Granted: 1991-03-12
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Expires: 2009-06-05
Abstract
Abstract A transmissive liquid crystal display device is comprised not only of a light scattering plate disposed behind a liquid crystal display cell, a light diffusing film disposed behind this light scattering plate and a light source lamp and a reflective plate disposed behind this light diffusing film but also of a transparent plate disposed between the light diffusing film and the light source lamp. The reflective plate serves to direct backward propagating light from the source lamp towards the liquid crystal display cell, and the transparent plate has an indentation formed on its back surface. This indentation is shaped correspondingly to the shape of the light source lamp and contains the light source lamp inside.
Inventors
- 👤 Kenji Horiuchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:29
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/133602; G02F1/133606; G02B; G02B6/00; G02B6/0001; G02B6/0011; G02B6/0013; G02B6/0015; G02B6/002; G02B6/0021; G02B6/0023; G02B6/0031; G02F1/133604
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
136 words
A transmissive liquid crystal display device comprising a liquid crystal display cell, a light scattering plate disposed behind said display cell, a light diffusing film disposed behind said light scattering plate, a light source lamp and a reflective plate disposed behind said light diffusing film, said reflective plate serving to direct backward propagating light from said source lamp towards said liquid crystal display cell, and a transparent plate disposed between said light diffusing film and said light source lamp, said transparent plate having at least one indentation each shaped correspondingly to the shape of said light source lamp, said light source lamp being contained inside said indentation, wherein emitted light from said source lamp reaches said light diffusing film both by directly passing through said transparent plate and by undergoing internal reflections inside said transparent plate.
Claim 2
Dependent Claim
136 words
A transmissive liquid crystal display device comprising a liquid crystal display cell, a light scattering plate disposed behind said display cell, a light diffusing film disposed behind said light scattering plate, a light source lamp and a reflective plate disposed behind said light diffusing film, said reflective plate serving to direct backward propagating light from said source lamp towards said liquid crystal display cell, and a transparent plate disposed between said light diffusing film and said light source lamp, said transparent plate having at least one indentation each shaped correspondingly to the shape of said light source lamp, said light source lamp being contained inside said indentation, wherein emitted light from said source lamp reaches said light diffusing film both by directly passing through said transparent plate and by undergoing internal reflections inside said transparent plate.
Claim 3
Dependent Claim
14 words
The device of claim 1 wherein said light diffusing film is an aluminum film.
Claim 4
Dependent Claim
20 words
The device of claim 1 wherein said light scattering plate comprises a translucent plate made of an acryl resin material.
Claim 5
Dependent Claim
16 words
The device of claim 1 wherein said transparent plate is made of acryl or polycarbonate resin.
Claim 6
Dependent Claim
14 words
The device of claim 1 wherein said transparent plate is made of quartz glass.
Claim 7
Dependent Claim
24 words
The device of claim 1 wherein said light source lamp is cylindrical and each of said indentation is a groove with a U-shaped cross-section.
Claim 8
Dependent Claim
27 words
The device of claim 1 wherein said light source lamp is spherical and each of said indentation is a circular hole with a hemispherically formed bottom surface.
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) | 1994-03-11 | 1994-09-10 | 1995-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-03-11 | 1998-09-10 | 1999-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-03-11 | 2002-09-10 | 2003-03-12 | $7700.00 | Window Closed / Lapsed |