Patent US4152092A successfully refreshed from Google Patents.
Patent US4423928A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4423928A Expired / Lapsed US ⏱️ 0.0 years remaining

Liquid crystal display device

Assignee: ETS SA A SWISS CORP
•
Filing: 1980-12-03
•
Granted: 1984-01-03
•
Expires: 2000-12-03
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The display device comprises a cell having two levels, between two polarizers 1 and 7, the directions of polarization of which are at an angle of 120° to each other. The two-level cell comprises two liquid crystal layers 5 and 6, each of which, in the rest condition, causes rotation of the plane of polarization of the light through 60°. The orientation of the molecules of the input surface of the first layer 5 is parallel to the direction of polarization P1 of the first polarizer 1. The orientation of the molecules of the input surface of the second layer 6 is parallel to the orientation of the molecules on the output face of the first layer 5. The orientation of the molecules of the output surface of the second layer 6 is parallel to the direction of polarization P2 of the second polarizer 7. This construction provides a two-level cell which is clear if the two liquid crystal layers are both in the rest condition, and which is dark in all other situations, whether one or the other or both layers 5, 6 are energized.

Inventors

  • 👤 Claude Laesser

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 08:34
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1347; G02F1/13471; G02F1/137; G02F1/139; G02F1/1396; G02F2203/00; G02F2203/01; G02F2203/02

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 204 words
A liquid crystal display device comprising, in sequence, a first polarizer, having a first direction of polarization, a first of three transparent insulating plates, a first nematic liquid crystal layer, the second plate, a second nematic liquid crystal layer, the third plate and a second polarizer having a second direction of polarization, said plates and said polarizers being substantially parallel and disposed in a facing relationship to each other, control electrodes disposed on said plates, and means for orienting the molecules of the first liquid crystal layer in contact with the first and the second plate in a first and a second direction of orientation respectively, and the molecules of the second liquid crystal layer in contact with the second and the third plate in a third and a fourth direction of orientation respectively, wherein said first direction of orientation is substantially parallel to said first direction of polarization, said first and second directions of orientation form an angle of substantially 60°, said third direction of orientation is substantially parallel to said second direction of orientation, said third and fourth directions of orientation form an angle of substantially 60°, and said second direction of polarization is substantially parallel to said fourth direction of orientation.
Claim 2
Dependent Claim 204 words
A liquid crystal display device comprising, in sequence, a first polarizer, having a first direction of polarization, a first of three transparent insulating plates, a first nematic liquid crystal layer, the second plate, a second nematic liquid crystal layer, the third plate and a second polarizer having a second direction of polarization, said plates and said polarizers being substantially parallel and disposed in a facing relationship to each other, control electrodes disposed on said plates, and means for orienting the molecules of the first liquid crystal layer in contact with the first and the second plate in a first and a second direction of orientation respectively, and the molecules of the second liquid crystal layer in contact with the second and the third plate in a third and a fourth direction of orientation respectively, wherein said first direction of orientation is substantially parallel to said first direction of polarization, said first and second directions of orientation form an angle of substantially 60°, said third direction of orientation is substantially parallel to said second direction of orientation, said third and fourth directions of orientation form an angle of substantially 60°, and said second direction of polarization is substantially parallel to said fourth direction of orientation.
Claim 3
Dependent Claim 214 words
A liquid crystal display device comprising in sequence, a first polarizer, having a first direction of polarization, a first of three transparent insulating plates, a first nematic liquid crystal layer, the second plate, a second nematic liquid crystal layer, the third plate, a second polarizer having a second direction of polarization and reflector means adjacent the outside face of said second polarizer, said plates and said polarizers being substantially parallel and disposed in a facing relationship to each other, control electrodes disposed on said plates, and means for orienting the molecules of the first liquid crystal layer in contact with the first and the second plate in a first and a second direction of orientation respectively, and the molecules of the second liquid crystal layer in contact with the second and the third plate in a third and a fourth direction of orientation respectively, wherein said first direction of orientation is substantially parallel to said first direction of polarization, said first and second directions of orientation form an angle of substantially 60°, said third direction of orientation is substantially parallel to said second direction of orientation, said third and fourth directions of orientation form an angle of substantially 60°, and said second direction of polarization is substantially parallel to said fourth direction of orientation.
Claim 4
Dependent Claim 214 words
A liquid crystal display device comprising in sequence, a first polarizer, having a first direction of polarization, a first of three transparent insulating plates, a first nematic liquid crystal layer, the second plate, a second nematic liquid crystal layer, the third plate, a second polarizer having a second direction of polarization and reflector means adjacent the outside face of said second polarizer, said plates and said polarizers being substantially parallel and disposed in a facing relationship to each other, control electrodes disposed on said plates, and means for orienting the molecules of the first liquid crystal layer in contact with the first and the second plate in a first and a second direction of orientation respectively, and the molecules of the second liquid crystal layer in contact with the second and the third plate in a third and a fourth direction of orientation respectively, wherein said first direction of orientation is substantially parallel to said first direction of polarization, said first and second directions of orientation form an angle of substantially 60°, said third direction of orientation is substantially parallel to said second direction of orientation, said third and fourth directions of orientation form an angle of substantially 60°, and said second direction of polarization is substantially parallel to said fourth direction of orientation.

References Cited (Backward Citations)

FR2206884A5 Cited
US3903519A Cited
GB1469638A Cited
FR2238200B1 Cited
GB1502783A Cited
CH592316A5 Cited
US4054368A Cited
US4099855A Cited
US4231639A Cited
US4240709A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-01-02 1987-07-04 1988-01-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-01-02 1991-07-04 1992-01-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-01-02 1995-07-04 1996-01-03 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag