US3716289A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-optical display devices using smectic-nematic liquid crystal mixtures
Assignee: Texas Instruments Inc
•
Filing: 1970-08-31
•
Granted: 1973-02-13
•
Expires: 1990-08-31
Abstract
Abstract A display device includes a layer of a smectic-nematic liquid crystal composition that is normally transparent to light. The composition is effective to scatter light in response to a voltage applied thereacross. The smetic-nematic compositions exhibit the mesomorphic state through a broad temperature range that preferably includes room temperature.
Inventors
- 👤 L Creagh
- 👤 D Jones
- 👤 Lu Sun
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:41
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/13781; C; C09; C09K; C09K19/00; C09K19/04; C09K19/42; C09K19/44; C09K19/48; G02F1/13743; G02F1/1375
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
104 words
In an electro-optical display device including a first optically transmissive substrate having an optically transmissive and electrically conducting coating on a face thereof, a second substrate having an electrically conductive coating on a face thereof, said substrate being positioned such that the coatings are adjacent and substantially equidistantly spaced, a light source means positioned to direct light toward the substrates, and means for impressing a voltage between selected portions of said coatings, the improvement comprising a nematic-smectic liquid crystal composition occupying the sPace between said coatings, said composition exhibiting dynamic scattering responsive to a voltage on the order of about 20 volts or less.
Claim 2
Dependent Claim
104 words
In an electro-optical display device including a first optically transmissive substrate having an optically transmissive and electrically conducting coating on a face thereof, a second substrate having an electrically conductive coating on a face thereof, said substrate being positioned such that the coatings are adjacent and substantially equidistantly spaced, a light source means positioned to direct light toward the substrates, and means for impressing a voltage between selected portions of said coatings, the improvement comprising a nematic-smectic liquid crystal composition occupying the sPace between said coatings, said composition exhibiting dynamic scattering responsive to a voltage on the order of about 20 volts or less.
Claim 3
Dependent Claim
23 words
The display device of claim 1 wherein about 1 to 10 percent by weight of cholesteric liquid crystal is added to said composition.
Claim 4
Dependent Claim
13 words
The display device of claim 1 wherein said second substrate is optically transmissive.
Claim 5
Dependent Claim
15 words
The display device of claim 1 wherein said second substrate is capable of reflecting light.
Claim 6
Dependent Claim
16 words
The display device of claim 4 wherein the second substrate has an optically reflective layer thereon.
Claim 7
Independent Claim
65 words
A method for displaying light from a light source comprising the steps of: a. directing a light beam at an angle toward a thin layer of a nematic-smectic liquid crystal composition which exhibits dynamic scattering responsive to an applied voltage, and b. impressing a voltage on the order of about 20 volts or less across said layer sufficient to cause said composition to scatter light.
Claim 8
Independent Claim
65 words
A method for displaying light from a light source comprising the steps of: a. directing a light beam at an angle toward a thin layer of a nematic-smectic liquid crystal composition which exhibits dynamic scattering responsive to an applied voltage, and b. impressing a voltage on the order of about 20 volts or less across said layer sufficient to cause said composition to scatter light.
Claim 9
Dependent Claim
46 words
A liquid crystal composition consisting essentially of a mixture of a smectic liquid crystal material and a nematic liquid crystal material, said mixture exhibiting dynamic scattering over a broad temperature range responsive to an applied voltage thereacross on the order of about 20 volts or less.
Claim 10
Dependent Claim
46 words
A liquid crystal composition consisting essentially of a mixture of a smectic liquid crystal material and a nematic liquid crystal material, said mixture exhibiting dynamic scattering over a broad temperature range responsive to an applied voltage thereacross on the order of about 20 volts or less.
Claim 11
Dependent Claim
125 words
In an electro-optical display device including a first optically transmissive substrate having an optically transmissive and electrically conducting coating on a face thereof, a second substrate having an electrically conductive coating on a face thereof, said substrate being positioned such that the coatings are adjacent and substantially equidistantly spaced, a light source means positioned to direct light toward the substrates, and means for impressing a voltage between selected portions of said coatings, the improvement comprising a nematic-smectic liquid crystal composition occupying the space between said coatings, said composition consisting essentially of from about 20 to 80 weight percentage of p-methoxybenzylidene-p-n-butylaniline and from about 20 to 80 weight percentage of 4,4''-bis(heptyloxy)azoxybenzene, and having a threshold electrical field which when exceeded causes the composition to scatter light.
Claim 12
Dependent Claim
125 words
In an electro-optical display device including a first optically transmissive substrate having an optically transmissive and electrically conducting coating on a face thereof, a second substrate having an electrically conductive coating on a face thereof, said substrate being positioned such that the coatings are adjacent and substantially equidistantly spaced, a light source means positioned to direct light toward the substrates, and means for impressing a voltage between selected portions of said coatings, the improvement comprising a nematic-smectic liquid crystal composition occupying the space between said coatings, said composition consisting essentially of from about 20 to 80 weight percentage of p-methoxybenzylidene-p-n-butylaniline and from about 20 to 80 weight percentage of 4,4''-bis(heptyloxy)azoxybenzene, and having a threshold electrical field which when exceeded causes the composition to scatter light.
Claim 13
Dependent Claim
125 words
In an electro-optical display device including a first optically transmissive substrate having an optically transmissive and electrically conducting coating on a face thereof, a second substrate having an electrically conductive coating on a face thereof, said substrate being positioned such that the coatings are adjacent and substantially equidistantly spaced, a light source means positioned to direct light toward the substrates, and means for impressing a voltage between selected portions of said coatings, the improvement comprising a nematic-smectic liquid crystal composition occupying the space between said coatings, said composition consisting essentially of from about 20 to 90 weight percentage of p-ethoxybenzylidene-p-n-butylaniline and from about 10 to 80 weight percentage of 4,4''-bis(heptyloxy)azoxybenzene, and having a threshold electrical field which when exceeded causes the composition to scatter light.
Claim 14
Dependent Claim
125 words
In an electro-optical display device including a first optically transmissive substrate having an optically transmissive and electrically conducting coating on a face thereof, a second substrate having an electrically conductive coating on a face thereof, said substrate being positioned such that the coatings are adjacent and substantially equidistantly spaced, a light source means positioned to direct light toward the substrates, and means for impressing a voltage between selected portions of said coatings, the improvement comprising a nematic-smectic liquid crystal composition occupying the space between said coatings, said composition consisting essentially of from about 20 to 90 weight percentage of p-ethoxybenzylidene-p-n-butylaniline and from about 10 to 80 weight percentage of 4,4''-bis(heptyloxy)azoxybenzene, and having a threshold electrical field which when exceeded causes the composition to scatter light.
Claim 15
Dependent Claim
126 words
In an electro-optical display device including a first optically transmissive substrate having an optically transmissive and electrically conducting coating on a face thereof, a second substrate having an electrically conductive coating on a face thereof, said substrate being positioned such that the coatings are adjacent and substantially equidistantly spaced, a light source means positioned to direct light toward the substrates, and means for impressing a voltage between selected portions of said coatings, the improvement comprising a nematic-smectic liquid crystal composition occupying the space between said coatings, said composition consisting essentially of from about 60 to 90 weight percentage of p-ethoxybenzylidene-p-n-butylaniline and from about 10 to 40 weight percentage of ethyl p-hexyloxybenzal-p-aminocinnamate, and having a threshold electrical field which when exceeded causes the composition to scatter light.
Claim 16
Dependent Claim
126 words
In an electro-optical display device including a first optically transmissive substrate having an optically transmissive and electrically conducting coating on a face thereof, a second substrate having an electrically conductive coating on a face thereof, said substrate being positioned such that the coatings are adjacent and substantially equidistantly spaced, a light source means positioned to direct light toward the substrates, and means for impressing a voltage between selected portions of said coatings, the improvement comprising a nematic-smectic liquid crystal composition occupying the space between said coatings, said composition consisting essentially of from about 60 to 90 weight percentage of p-ethoxybenzylidene-p-n-butylaniline and from about 10 to 40 weight percentage of ethyl p-hexyloxybenzal-p-aminocinnamate, and having a threshold electrical field which when exceeded causes the composition to scatter light.
Claim 17
Dependent Claim
126 words
In an electro-optical display device including a first optically transmissive substrate having an optically transmissive and electrically conducting coating on a face thereof, a second substrate having an electrically conductive coating on a face thereof, said substrate being positioned such that the coatings are adjacent and substantially equidistantly spaced, a light source means positioned to direct light toward the substrates, and means for impressing a voltage between selected portions of said coatings, the improvement comprising a nematic-smectic liquid crystal composition occupying the space between said coatings, said composition consisting essentially of from about 10 to 20 weight percentage of ethyl p-hexyloxybenzal-p-aminocinnamate and from about 80 to 90 weight percentage of p-methoxybenzylidene-p-n-butylaniline, and having a threshold electrical field which when exceeded causes the composition to scatter light.
Claim 18
Dependent Claim
126 words
In an electro-optical display device including a first optically transmissive substrate having an optically transmissive and electrically conducting coating on a face thereof, a second substrate having an electrically conductive coating on a face thereof, said substrate being positioned such that the coatings are adjacent and substantially equidistantly spaced, a light source means positioned to direct light toward the substrates, and means for impressing a voltage between selected portions of said coatings, the improvement comprising a nematic-smectic liquid crystal composition occupying the space between said coatings, said composition consisting essentially of from about 10 to 20 weight percentage of ethyl p-hexyloxybenzal-p-aminocinnamate and from about 80 to 90 weight percentage of p-methoxybenzylidene-p-n-butylaniline, and having a threshold electrical field which when exceeded causes the composition to scatter light.
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) | 1976-02-13 | 1976-08-14 | 1977-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-13 | 1980-08-14 | 1981-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-13 | 1984-08-14 | 1985-02-13 | $7700.00 | Window Closed / Lapsed |