US4974941A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of aligning and realigning liquid crystal media
Assignee: Elsicon Inc
•
Filing: 1989-03-08
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Granted: 1990-12-04
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Expires: 2009-03-08
Abstract
Abstract A process of aligning or realigning a liquid crystal medium adjacent to a coated or uncoated substrate comprising exposing anisotropically absorbing molecules to linearly polarized light of a wavelength or wavelengths within the absorption band of the anisotropically absorbing molecules, wherein (a) the exposed anisotropically absorbing molecules induce alignment of the liquid crystal medium at an angle + and -θ with respect to the direction of the linear polarization of the incident light beam and along a surface of the liquid crystal medium and (b) the liquid crystal medium comprises liquid crystals having a molecular weight of less than 1500, and liquid crystal cells and devices prepared by this process, are disclosed.
Inventors
- 👤 Wayne M. Gibbons
- 👤 Shao-Tang Sun
- 👤 Brian J. Swetlin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 04:38
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/13725; C; C09; C09K; C09K19/00; C09K19/52; C09K19/54; C09K19/56; C09K19/60; C09K19/606; G02F1/133; G02F1/1333; G02F1/1337; G02F1/133711; G02F1/13378; G02F1/133788; G11; G11B; G11B7/00; G11B7/004; G11B7/0055; G11B7/00555; G11B7/24; G11B7/241; G11B7/242; G11B7/244; G11B7/25; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
136 words
A process of aligning or realigning a liquid crystal medium adjacent to a substrate which process comprises exposing anisotropically absorbing molecules disposed on the substrate, disposed in the liquid crystal medium or which themselves are the liquid crystal medium to linearly polarized light of a wavelength or wavelengths within the absorption band of the anisotropically absorbing molecules, wherein (a) the exposed anisotropically absorbing molecules induce alignment of the liquid crystal medium at an angle + and -θ with respect to the direction of the linear polarization of the incident light beam and along a surface of the liquid crystal medium and (b) the liquid crystal medium comprises liquid crystals having a molecular weight of less than 1500, and terminating exposure whereby the liquid crystal medium aligned or realigned by the exposure step remains aligned or realigned.
Claim 2
Dependent Claim
136 words
A process of aligning or realigning a liquid crystal medium adjacent to a substrate which process comprises exposing anisotropically absorbing molecules disposed on the substrate, disposed in the liquid crystal medium or which themselves are the liquid crystal medium to linearly polarized light of a wavelength or wavelengths within the absorption band of the anisotropically absorbing molecules, wherein (a) the exposed anisotropically absorbing molecules induce alignment of the liquid crystal medium at an angle + and -θ with respect to the direction of the linear polarization of the incident light beam and along a surface of the liquid crystal medium and (b) the liquid crystal medium comprises liquid crystals having a molecular weight of less than 1500, and terminating exposure whereby the liquid crystal medium aligned or realigned by the exposure step remains aligned or realigned.
Claim 3
Dependent Claim
21 words
The process as claimed in claim 1 wherein the linearly polarized light has a wavelength in the ultraviolet through infrared range.
Claim 4
Dependent Claim
22 words
The process as in claim 1 wherein the linearly polarized light has a wavelength between about 150 nm and about 2000 nm.
Claim 5
Dependent Claim
17 words
The process as claimed in claim 1 wherein the linearly polarized light is emitted from a laser.
Claim 6
Dependent Claim
21 words
The process as claimed in claim 4 wherein the laser light is emitted from an argon, helium neon or helium-cadmium laser.
Claim 7
Dependent Claim
37 words
The process of claim 1 wherein the anisotropically absorbing molecules are selected from the group consisting of thermotropic liquid crystal compounds and dichroic dyes which exhibit dichroic absorption bands between about 150 nm and about 2000 nm.
Claim 8
Dependent Claim
16 words
The process as in claim 1 wherein the liquid crystal medium contains the anisotropically absorbing molecules.
Claim 9
Dependent Claim
15 words
The process as in claim 7 wherein the anisotropically absorbing molecules are thermotropic liquid crystals.
Claim 10
Dependent Claim
32 words
The process as claimed in claim 1 wherein the liquid crystal medium comprises at least one thermotropic liquid crystal compound selected from the group consisting of nematic and smectic liquid crystal compounds.
Claim 11
Dependent Claim
32 words
The process as claimed in claim 7 wherein the liquid crystal medium comprises at least one thermotropic liquid crystal compound selected from the group consisting of nematic and smectic liquid crystal compounds.
Claim 12
Dependent Claim
25 words
The process as claimed in claim 8 wherein the thermotropic liquid crystals are selected from the group consisting of nematic and smectic liquid crystal compounds.
Claim 13
Dependent Claim
21 words
The process as claimed in claim 1 wherein the liquid crystal medium comprises at least one thermotropic nematic liquid crystal compound.
Claim 14
Dependent Claim
21 words
The process as claimed in claim 1 wherein the liquid crystal medium comprises at least one thermotropic smectic liquid crystal compound.
Claim 15
Dependent Claim
21 words
The process as claimed in claim 1 wherein the liquid crystal medium comprises at least one thermotropic ferroelectric liquid crystal compound.
Claim 16
Dependent Claim
39 words
The process as claimed in claim 1 wherein the liquid crystal medium comprises at least one dichroic dye which exhibits dichroic absorption between about 150 nm and about 2000 nm dissolved in at least one thermotropic liquid crystal compound.
Claim 17
Dependent Claim
46 words
The process as claimed in claim 14 wherein the dichroic dye is selected from the group consisting of azo, diazo, triazo, tetraazo, pentaazo, anthraquinone, mericyanine, methine, 2-phenylazothiazole, 2-phenylazobenzthiazole, 4,4'-bis(arylazo)stilbenes, perylene and 4,8-diamino-1,5-naphthoquinone dyes that exhibit dichroic absorption bands between about 150 nm and about 2000 nm.
Claim 18
Dependent Claim
20 words
The process as claimed in claim 15 wherein the anistropically absorbing molecules are one or more of the dichroic dyes.
Claim 19
Dependent Claim
46 words
The process as claimed in claim 17 wherein the dichroic dyes are selected from the group consisting of azo, diazo, triazo, tetraazo, pentaazo, anthraquinone, mericyanine, methine, 2-phenylazothiazole, 2-phenylazobenzthiazole, 4,4'-bis(arylazo)stilbenes, perylene and 4,8-diamino-1,5-naphthoquinone dyes that exhibit dichroic absorption bands between about 150 nm and about 2000 nm.
Claim 20
Dependent Claim
18 words
The process as claimed in claim 1 wherein the liquid crystal medium does not contain a dichroic dye.
Claim 21
Dependent Claim
18 words
The process as claimed in claim 1 which is carried out in the presence of an electric field.
Claim 22
Dependent Claim
18 words
The process as claimed in claim 1 which is carried out in the absence of an electric field.
Claim 23
Dependent Claim
18 words
The process as claimed in claim 1 which is carried out in the presence of a heat source.
Claim 24
Dependent Claim
16 words
The process as claimed in claim 1 which is carried out without an external heat source.
Claim 25
Dependent Claim
25 words
The process as claimed in claim 1 further comprising that the liquid crystal medium is filled into a cell comprising a front and rear substrate.
Claim 26
Dependent Claim
19 words
The process of claim 24 wherein exposure to linearly polarized light is carried out after the cell is filled.
Claim 27
Dependent Claim
19 words
The process of claim 24 wherein at least one of the substances is coated with a rubbed alignment layer.
Claim 28
Dependent Claim
15 words
The process of claim 24 wherein the substrates are not coated with an alignment layer.
Claim 29
Dependent Claim
37 words
The process as claimed in claim 26 wherein the anisotropically absorbing molecules comprise at least one dichroic dye which exhibit dichroic absorption between about 150 nm and about 2000 nm which is part of the alignment layer.
Claim 30
Dependent Claim
35 words
The process as claimed in claim 28 wherein the liquid crystal medium also contains anisotropically absorbing molecules comprising at least one dichroic dye which exhibit dichroic absorption between about 150 nm and about 2000 nm.
Claim 31
Dependent Claim
22 words
The process as claimed in claim 1 wherein the liquid crystal medium is aligned into a homogeneous state from an isotropic state.
Claim 32
Dependent Claim
23 words
The process as claimed in claim 1 wherein the liquid crystal medium is realigned from one homogeneous state into a different homogeneous state.
Claim 33
Dependent Claim
25 words
The process as claimed in claim 20 wherein the liquid crystal medium has a negative dielectric anisotropy and is originally aligned in a homeotropic state.
Claim 34
Dependent Claim
18 words
The process as claimed in claim 24 wherein the entire liquid crystal medium in the cell is realigned.
Claim 35
Dependent Claim
34 words
The process as claimed in claim 24 wherein one of more sections of the liquid crystal medium in the cell are realigned into a different orientation than another section of the liquid crystal medium.
Claim 36
Dependent Claim
52 words
The process as claimed in claim 24 wherein the anisotropically absorbing molecules are selected from the group consisting of dichroic dyes which exhibit dichroic absorption between about 150 nm and about 2000 nm and the dichroic dyes are coated on at least one inner surface of a cell substrate prior to exposure.
Claim 37
Dependent Claim
23 words
The process as claimed in claim 1 wherein the liquid crystal medium comprises liquid crystals having a molecular weight of 1000 or less.
Claim 38
Dependent Claim
23 words
The process as claimed in claim 1 wherein the liquid crystal medium comprises liquid crystals having a molecular weight of 650 or less.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-03 | 1994-06-04 | 1994-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-03 | 1998-06-04 | 1998-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-03 | 2002-06-04 | 2002-12-04 | $7700.00 | Window Closed / Lapsed |