Patent US5039207A successfully refreshed from Google Patents.
US5039207A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid crystal display device with prismatic light transmitting member
Assignee: Central Research Laboratories Ltd
•
Filing: 1989-07-17
•
Granted: 1991-08-13
•
Expires: 2009-07-17
Abstract
Abstract A liquid crystal device comprises backlighting means to provide illumination from the rear for a liquid crystal panel. The backlighting means has a layer of light-transmitting material formed with a prismatic region at one edge and a plurality of light sources of differing chromatic output, located adjacent the prismatic region.
Inventors
- 👤 Bernard J. Green
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:42
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/133621; G02F1/133622
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
70 words
Apparatus including a plurality of light sources for backlighting a liquid crystal device comprising a light transmitting member formed with an integral prismatic region at one edge thereof, the prismatic region arranged to be receptive to light from the plurality of light sources which light sources are arranged to provide a plurality of chromatic outputs, for providing a substantially uniform illumination of the light transmitting member for each chromatic output.
Claim 2
Dependent Claim
70 words
Apparatus including a plurality of light sources for backlighting a liquid crystal device comprising a light transmitting member formed with an integral prismatic region at one edge thereof, the prismatic region arranged to be receptive to light from the plurality of light sources which light sources are arranged to provide a plurality of chromatic outputs, for providing a substantially uniform illumination of the light transmitting member for each chromatic output.
Claim 3
Dependent Claim
65 words
Apparatus according to claim 1 wherein the backlighting member comprises a planar member with two major surfaces thereof and two further respective faces extending therefrom at the one edge such that each of the two further faces protrudes from one of the two major faces at an angle such that the two further faces converge to meet at an apex thereby forming the prismatic region.
Claim 4
Dependent Claim
77 words
Apparatus according to claim 1 wherein the backlighting member comprises a planar member with two major surfaces thereof and two further respective faces extending therefrom at the one edge such that each of the two further faces protrudes from one of the two major faces at an angle such that the two further faces diverge thereby to form the prismatic region, the prismatic region having a base portion which is substantially normal to the two major surfaces.
Claim 5
Dependent Claim
35 words
Apparatus according to claim 2 wherein the light sources are located adjacent to major faces of the prismatic region such that they lie on a cylindrical plane centred around the apex of the prismatic region.
Claim 6
Dependent Claim
38 words
Apparatus according to claim 2 wherein the light transmitting member has a further edge, remote from the one edge thereof, arranged to bear a light reflective coating directing light from the light sources back into the planar member.
Claim 7
Dependent Claim
24 words
Apparatus according to claim 5 wherein the further edge is arranged to have a concave curvature as viewed from outside the light transmitting member.
Claim 8
Dependent Claim
38 words
Apparatus according to claim 3 wherein the base portion is arranged to bear a coating for providing a dichroic colour separating mirror thereby to permit optical transmission of one chromatic output and to reflect all other chromatic outputs.
Claim 9
Dependent Claim
68 words
Apparatus according to claim 1 wherein the light transmitting member includes opposed major surfaces and the substantially uniform illumination of the light transmitting member for each chromatic output is arranged for emission via a major surface thereof, the liquid crystal device being arranged adjacent to the said major surface for emission of each chromatic output, whereby the light sources cannot be viewed directly through the liquid crystal device.
Claim 10
Dependent Claim
68 words
Apparatus according to claim 2 wherein the light transmitting member includes opposed major surfaces and the substantially uniform illumination of the light transmitting member for each chromatic output is arranged for emission via a major surface thereof, the liquid crystal device being arranged adjacent to the said major surface for emission of teach chromatic output, whereby the light sources cannot be viewed directly through the liquid crystal device.
Claim 11
Dependent Claim
68 words
Apparatus according to claim 3 wherein the light transmitting member includes opposed major surfaces and the substantially uniform illumination of the light transmitting member for each chromatic output is arranged for emission via a major surface thereof, the liquid crystal device being arranged adjacent to the said major surface for emission of each chromatic output, whereby the light sources cannot be viewed directly through the liquid crystal device.
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) | 1994-08-12 | 1995-02-11 | 1995-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-12 | 1999-02-11 | 1999-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-12 | 2003-02-11 | 2003-08-13 | $7700.00 | Window Closed / Lapsed |