US3796479A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-optical light-modulation cell utilizing a nematogenic material which exhibits the kerr effect at isotropic temperatures
Assignee: F Hoffmann La Roche AG
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Filing: 1972-07-11
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Granted: 1974-03-12
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Expires: 1992-07-11
Abstract
Abstract An electro-optical light-modulation cell having a dielectric disposed between electrodes and being comprised of a nematogenic fluid in the isotropic state, is described. Said dielectric, upon application of a voltage to the electrodes, becomes doubly refracting.
Inventors
- 👤 W Helfrich
- 👤 M Schadt
- 👤 H Scherrer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:12
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/07
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
30 words
A cell in accordance with claim 1, wherein the nematogenic fluid is at a temperature near the temperature Tc of the phase change between the isotropic and the anisotropic state.
Claim 2
Dependent Claim
29 words
A cell in accordance with claim 2, wherein the temperature t of the nematogenic fluid is in the range Tc < t < or = Tc + 1* C.
Claim 3
Dependent Claim
18 words
A cell in accordance with claim 3, wherein the dielectric comprises a 1:1:1-mixture of N-(4''-butoxybenzylidene)-4-aminobenzonitrile, N-(4''-hexoxybenzylidene)-4-aminobenzonitrile and N-(4''-octoyloxybenzylidene)-4-aminobenzonitrile.
Claim 4
Dependent Claim
12 words
A cell in accordance with claim 3, wherein the dielectric comprises N-(4''-ethoxybenzylidene)-4-aminobenzonitrile.
Claim 5
Dependent Claim
17 words
A cell in accordance with claim 3, wherein the dielectric comprises a 1:1-mixture of N-(4''-butoxybenzylidene)-4-aminobenzonitrile and N-(4''-butoxybenzylidene)-4-nitroaniline.
Claim 6
Dependent Claim
12 words
A cell in accordance with claim 3, wherein the dielectric comprises 4''-cyanophenyl-4-hexobenzoate.
Claim 7
Dependent Claim
12 words
A cell in accordance with claim 3, wherein the dielectric comprises 4-cyano-4''-hexoxyazobenzene.
Claim 8
Dependent Claim
17 words
A cell in accordance with claim 3, wherein the dielectric comprises a 9:1-mixture of N-(4''-butoxybenzylidene)-4-aminobenzonitrile and N-(4''-dimethylaminobenzylidene)-4-nitroaniline.
Claim 9
Dependent Claim
17 words
A ceLl in accordance with claim 3, wherein the dielectric comprises an 85:15-mixture of N-(4''-butoxybenzylidene)-4-aminobenzonitrile and N-(4''-dimethylaminobenzylidene)-4-aminobenzonitrile.
Claim 10
Dependent Claim
44 words
A cell in accordance with claim 3, which comprises polarizers for continuously modulating light transmitted through the cell, one polarizer being disposed upstream of the cell and the other being disposed downstream of the cell in the direction of light traveling through the cell.
Claim 11
Dependent Claim
12 words
A cell according to claim 11, wherein the two polarizers are crossed.
References Cited (Backward Citations)
US3687515A
Cited
US3694053A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-11 | 1977-09-10 | 1978-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-11 | 1981-09-10 | 1982-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-11 | 1985-09-10 | 1986-03-12 | $7700.00 | Window Closed / Lapsed |