US3687515A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-optic liquid crystal system with polyamide resin additive
Assignee: Xerox Corp
•
Filing: 1971-01-06
•
Granted: 1972-08-29
•
Expires: 1991-01-06
Abstract
Abstract An electro-optic system wherein a layer of nematic liquid crystalline composition which is optically uniaxial with the optic axis normal to the plane of the layer has an electrical field applied perpendicular to the optic axis of the composition layer thereby inducing optical biaxiality in the composition layer. Electro-optic cells and imaging systems are disclosed using the optic retardation accompanying a field induced change from the uniaxial to the biaxial state.
Inventors
- 👤 Werner E L Haas
- 👤 James E Adams
- 👤 John B Flannery Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:05
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/139; G02F1/1393
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
17 words
The method of claim 1 wherein the layer of nematic liquid crystalline composition contacts a supporting surface.
Claim 2
Dependent Claim
25 words
The method of claim 1 wherein the layer of nematic liquid crystalline composition contacts two approximately parallel surfaces of at least two substantially transparent members.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein said layer is of a thickness not greater than about 250 microns.
Claim 4
Dependent Claim
29 words
A method of claim 1 wherein the width of said layer in the direction normal to the direction of the optic axes is not greater than about 20 millimeters.
Claim 5
Dependent Claim
28 words
The method of claim 1 wherein said electrical field is of a field strength not greater than about 3,500 volts/cm. of width of the nematic liquid crystalline composition.
Claim 6
Dependent Claim
28 words
The method of claim 1 wherein said electrical field is of a field strength not greater than about 1,500 volts/cm. of width of the nematic liquid crystalline composition.
Claim 7
Dependent Claim
20 words
The method of claim 1 wherein the layer of nematic liquid crystalline composition is observed between polarizers in transmitted light.
Claim 8
Dependent Claim
16 words
The method of claim 8 wherein the light is collimated before transmission into the first polarizer.
Claim 9
Dependent Claim
17 words
The method of claim 8 wherein said polarizers are crossed at an angle of about 90* .
Claim 10
Dependent Claim
26 words
The method of claim 10 wherein the direction of the electrical field makes an angle of about 45* with the direction of vibration of the polarizers.
Claim 11
Dependent Claim
26 words
The method of claim 1 wherein the nematic liquid crystalline composition comprises a compound selected from the group consisting of p-methoxy-benzylidene-p''-n-butylaniline; methoxybenzylidene-amino-butyrophenone; methoxybenzylidene-aminovalerophenone; and mixtures thereof.
Claim 12
Dependent Claim
38 words
The method of claim 1 wherein the electrical field is of strength sufficient to produce interference hues in the composition layer and said electrical field is varied to provide various interference hues corresponding to different electrical field strengths.
Claim 13
Dependent Claim
30 words
The method of claim 1 wherein said electrical field is provided across the nematic liquid crystalline composition by a pair of electrodes located at opposite edges of the composition layer.
Claim 14
Dependent Claim
18 words
The method of claim 14 wherein said electrodes are of a thickness not greater than about 250 microns.
Claim 15
Dependent Claim
85 words
An electro-optic display apparatus comprising a plurality of individual cells, said individual cells comprising a layer of electro-optic composition comprising nematic liquid crystalline composition including from about 0.1 percent to about 10 percent by weight of a polyamide resin between two approximately parallel surfaces of at least two substantially transparent members, and a pair of electrodes at two opposite edges of said layer of electro-optic composition, and means for selectively providing an electrical field between the electrodes of at least one of the individual cells.
Claim 16
Dependent Claim
21 words
The apparatus of claim 16 wherein the thickness of the layer of electro-optic composition is not greater than about 250 microns.
Claim 17
Dependent Claim
22 words
The apparatus of claim 16 wherein the distance between the electrodes in the individual cells is not greater than about 20 millimeters.
Claim 18
Dependent Claim
20 words
The apparatus of claim 16 wherein the electrodes of the plurality of individual cells are arranged parallel to each other.
Claim 19
Dependent Claim
14 words
The apparatus of claim 16 wherein the surfaces of the individual cells are coplanar.
Claim 20
Dependent Claim
43 words
The apparatus of claim 20 additionally comprising polarizers on the opposite surfaces of the coplanar cells, and a source of collimated light oriented so that the collimated beam provided by said source is approximately normal to the coplanar surfaces of the display apparatus.
Claim 21
Dependent Claim
53 words
The apparatus of claim 21 wherein said polarizers are crossed at an angle of about 90*, and the electrodes of the plurality of individual cells are arranged parallel to each other, and the direction of the electrodes and the direction of vibration of the polarizers cross at an angle of about 45* .
Claim 22
Dependent Claim
59 words
The apparatus of claim 22 wherein the means for selectively providing an electrical field between the electrodes of at least one of the individual cells, is capable of providing an electrical field of field strength not greater than about 3,500 volts/cm. across the width of any one of or any combination of any of the plurality of individual cells.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-29 | 1976-02-28 | 1976-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-29 | 1980-02-28 | 1980-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-29 | 1984-02-28 | 1984-08-29 | $7700.00 | Window Closed / Lapsed |