Patent US4848090A successfully refreshed from Google Patents.
Patent US3942870A successfully refreshed from Google Patents.
US3942870A
Expired / Lapsed
US
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Liquid crystalline optical filter
Assignee: Xerox Corp
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Filing: 1974-04-29
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Granted: 1976-03-09
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Expires: 1994-04-29
Abstract
Abstract The optical transitions of extrinsically optically active insoluble materials become optically active and circularly dichroic when in contact with optically negative liquid crystalline materials thereby providing unusual and highly advantageous properties. The circularly dichroic optical properties induced in the extrinsically optically active insoluble materials can be utilized for optical filter applications.
Inventors
- 👤 Franklin D. Saeva
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 06:30
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/13725; C; C09; C09K; C09K19/00; C09K19/04; C09K19/36; C09K19/52; C09K19/60; G02B; G02B5/00; G02B5/30; G02B5/3016; C09K2019/523; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
175 words
A method for producing circularly polarized light of desired wavelengths of incident radiation while not affecting all other wavelengths of the incident radiation comprising: a. providing a light source; b. providing an optical filter comprising at least one film of an optically negative liquid crystalline material having a reflection band with center wavelength λ o and exhibiting reflective circularly dichroic behavior; said optically negative liquid crystalline film having dispersed therein an insoluble material; said insoluble material when dispersed in said optically negative liquid crystalline material becoming extrinsically optically active and having a light absorption band outside said reflection band within which circular dichroism is induced; and c. directing a beam of radiation from said light source upon said optical filter thereby providing an emergent light beam containing a wavelength band of circularly polarized light corresponding to the absorption band of said insoluble material; wherein said insoluble material is selected from the group consisting of non-polymeric aromatic compounds; azo compounds; nitro compounds; nitroso compounds; anyl compounds; carbonyl compounds; thiocarbonyl compounds; alkenes; heterocyclic compounds; and mixtures thereof.
Claim 2
Independent Claim
175 words
A method for producing circularly polarized light of desired wavelengths of incident radiation while not affecting all other wavelengths of the incident radiation comprising: a. providing a light source; b. providing an optical filter comprising at least one film of an optically negative liquid crystalline material having a reflection band with center wavelength λ o and exhibiting reflective circularly dichroic behavior; said optically negative liquid crystalline film having dispersed therein an insoluble material; said insoluble material when dispersed in said optically negative liquid crystalline material becoming extrinsically optically active and having a light absorption band outside said reflection band within which circular dichroism is induced; and c. directing a beam of radiation from said light source upon said optical filter thereby providing an emergent light beam containing a wavelength band of circularly polarized light corresponding to the absorption band of said insoluble material; wherein said insoluble material is selected from the group consisting of non-polymeric aromatic compounds; azo compounds; nitro compounds; nitroso compounds; anyl compounds; carbonyl compounds; thiocarbonyl compounds; alkenes; heterocyclic compounds; and mixtures thereof.
Claim 3
Dependent Claim
22 words
The method as defined in claim 1 wherein said liquid crystal film is from about 0.5 to about 50 microns in thickness.
Claim 4
Dependent Claim
30 words
The method as defined in claim 1 wherein said light absorption band of at least one said extrinsically optically active material is in the visible region of the electromagnetic spectrum.
Claim 5
Dependent Claim
24 words
The method as defined in claim 1 wherein the insoluble material content of said liquid crystalline film comprises up to about 90% by weight.
Claim 6
Dependent Claim
29 words
The method as defined in claim 1 wherein said dispersed insoluble material is selected from the group consisting of the calcium salt of 3'-ethyl-4'-chloro-6'-sulfonylphenylazo-2-hydroxy-3-naphthoic acid and calcium anthracene-9-carboxylic acid.
Claim 7
Dependent Claim
36 words
The method as defined in claim 1 further including the step of applying an electrical field across said liquid crystalline material; said electrical field being insufficient to extinguish said circular dichroism in said light absorption band.
Claim 8
Independent Claim
147 words
A method of producing circularly polarized light of desired wavelengths of incident radiation while not affecting all other wavelengths of the incident radiation, comprising: a. providing a light source; b. providing an optical filter comprising at least one film of an optically negative liquid crystalline material having a reflection band with center wavelength λ o and exhibiting reflective circularly dichroic behavior; said optically negative liquid crystalline material being in contact with a layer of insoluble material; said insoluble material when in contact with said optically negative liquid crystalline material becoming extrinsically optically active and having a light absorption band outside said reflection band within which circular dichroism is induced; and c. directing a beam of radiation from said light source upon said optical filter thereby providing an emergent light beam containing a wavelength band of circularly polarized light corresponding to the absorption band of said insoluble material.
Claim 9
Independent Claim
147 words
A method of producing circularly polarized light of desired wavelengths of incident radiation while not affecting all other wavelengths of the incident radiation, comprising: a. providing a light source; b. providing an optical filter comprising at least one film of an optically negative liquid crystalline material having a reflection band with center wavelength λ o and exhibiting reflective circularly dichroic behavior; said optically negative liquid crystalline material being in contact with a layer of insoluble material; said insoluble material when in contact with said optically negative liquid crystalline material becoming extrinsically optically active and having a light absorption band outside said reflection band within which circular dichroism is induced; and c. directing a beam of radiation from said light source upon said optical filter thereby providing an emergent light beam containing a wavelength band of circularly polarized light corresponding to the absorption band of said insoluble material.
Claim 10
Dependent Claim
22 words
The method as defined in claim 7 wherein said liquid crystal film is from about 0.5 to about 50 microns in thickness.
Claim 11
Dependent Claim
25 words
The method as defined in claim 7 wherein said light absorption band of said insoluble material is in the visible region of the electromagnetic spectrum.
Claim 12
Dependent Claim
49 words
The method as defined in claim 7 further including the step of applying an electrical field across said layer of liquid crystalline material and said layer of insoluble material; said electrical field being applied at a level insufficient to extinguish the circular dichroism induced in said light absorption band.
Claim 13
Dependent Claim
23 words
The method as defined in claim 7 wherein said insoluble material is selected from the group consisting of vanadyl phthalocyanine and copper phthalocyanine.
References Cited (Backward Citations)
US3697150A
Cited
US3780307A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-03-09 | 1979-09-08 | 1980-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-09 | 1983-09-08 | 1984-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-09 | 1987-09-08 | 1988-03-09 | $7700.00 | Window Closed / Lapsed |