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US4556289A Expired / Lapsed US ⏱️ 0.0 years remaining

Low birefringence encapsulated liquid crystal and optical shutter using same

Assignee: R & D PARTNERSHIP A OF OH LP
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Filing: 1983-03-21
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Granted: 1985-12-03
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Expires: 2003-03-21
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Abstract

Abstract Briefly, a liquid crystal material composition has a low, preferably zero or near zero, birefringence characteristic. Such material is mixed with a quantity of pleochroic dye to form a solution therewith to increase absorption characteristics and is encapsulated; and such encapsulated material may be used as an optical light control device or optical shutter in which light intensity may be controlled without distorting or at least without substantially distorting the optical image transmitted therethrough.

Inventors

  • 👤 James L. Fergason

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 04:12
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/137; G02F1/13725; G02F1/133; G02F1/1333; G02F1/1334

Claims Analysis

Total Claims: 66
Claim 1
Independent Claim 53 words
A method of making a light control device of low birefringence liquid crystal material comprising mixing low birefringence liquid crystal material and an encapsulating medium to form an emulsion of capsule-like containment media containing discrete quantities of liquid crystal material, and adding pleochroic dye to the mixture of low birefringence liquid crystal material.
Claim 2
Independent Claim 53 words
A method of making a light control device of low birefringence liquid crystal material comprising mixing low birefringence liquid crystal material and an encapsulating medium to form an emulsion of capsule-like containment media containing discrete quantities of liquid crystal material, and adding pleochroic dye to the mixture of low birefringence liquid crystal material.
Claim 3
Dependent Claim 48 words
The method of claim 1, further comprising making said liquid crystal material by mixing at least two liquid crystal materials, one having one twist characteristic and one having an opposite twist characteristic, whereby such twist characteristics substantially cause a near zero effective twist characteristic for the combined material.
Claim 4
Dependent Claim 24 words
The method of claim 2, further comprising applying the overall mixture to a generally optically transmissive support for controlling light transmission through said support.
Claim 5
Independent Claim 72 words
A method of controlling light transmitted through a medium having an optically transparent characteristic comprising applying to such medium an encapsulated low birefringence operationally nematic liquid crystal material containing pleochroic dye, and controlling the direction of the pleochroic dye without substantially scattering light having an image characteristic impinging on such liquid crystal and pleochroic dye thereby to control the intensity of transmitted light while substantially preserving the image of such transmitted light.
Claim 6
Independent Claim 72 words
A method of controlling light transmitted through a medium having an optically transparent characteristic comprising applying to such medium an encapsulated low birefringence operationally nematic liquid crystal material containing pleochroic dye, and controlling the direction of the pleochroic dye without substantially scattering light having an image characteristic impinging on such liquid crystal and pleochroic dye thereby to control the intensity of transmitted light while substantially preserving the image of such transmitted light.
Claim 7
Dependent Claim 33 words
The method of claim 4, further comprising distorting the natural structure of such liquid crystal material by such containment medium thereby to distort the pleochroic dye to increase light absorption by such dye.
Claim 8
Dependent Claim 36 words
The method of claim 5, further comprising applying a controlled electric field across said encapsulated liquid crystal material to control alignment of liquid crystal structure and pleochroic dye thereby to control the intensity of transmitted light.
Claim 9
Dependent Claim 61 words
The method of claim 4, wherein such encapsulated liquid crystal material is formed of liquid crystal material and a containment medium, such containment medium having an index of refraction, and further comprising selecting such low birefringence operationally nematic liquid crystal material and such containment medium such that the difference between the indices of refraction thereof is no greater than about 0.03.
Claim 10
Dependent Claim 59 words
The method of claim 4, further comprising mixing low birefringence operationally nematic liquid crystal material with an encapsulating medium to form with such liquid crystal material such encapsulated low birefringence operationally nematic liquid crystal material, and selecting such low birefringence liquid crystal material and containment medium to have indices of refraction that differ by from 0 to about 0.03.
Claim 11
Dependent Claim 43 words
An optical apparatus through which an image may be clearly viewed in all operational modes of said apparatus, comprising a low birefringence encapsulated liquid crystal material of operationally nematic liquid crystal in a containment medium, and pleochroic dye in said liquid crystal material.
Claim 12
Dependent Claim 43 words
An optical apparatus through which an image may be clearly viewed in all operational modes of said apparatus, comprising a low birefringence encapsulated liquid crystal material of operationally nematic liquid crystal in a containment medium, and pleochroic dye in said liquid crystal material.
Claim 13
Dependent Claim 37 words
The apparatus of claim 9, said low birefringence liquid crystal material comprising a mixture of at least one liquid crystal material having one twist characteristic and at least one liquid crystal material having an opposite twist characteristic.
Claim 14
Dependent Claim 22 words
The apparatus of claim 10, wherein each of said liquid crystal materials is operationally nematic or the combination thereof is operationally nematic.
Claim 15
Dependent Claim 15 words
The apparatus of claim 11, each of said liquid crystal materials comprising a cholesterol derivative.
Claim 16
Dependent Claim 23 words
The apparatus of claim 10, at least one of said liquid crystal materials comprising cholesteryl chloride and at least one comprising cholesteryl oleate.
Claim 17
Dependent Claim 27 words
The apparatus of claim 9, said low birefringence encapsulated liquid crystal material having a characteristic that it does not substantially distort image characteristic of light transmitted therethrough.
Claim 18
Dependent Claim 23 words
The apparatus of claim 9, further comprising electrode means for applying an electric field across at least some of such liquid crystal material.
Claim 19
Dependent Claim 18 words
The apparatus of claim 15, further comprising electrical circuit means for providing electrical power to said electrode means.
Claim 20
Dependent Claim 51 words
The apparatus of claim 9, said encapsulated liquid crystal material comprising an emulsion of liquid crystal material in a containment medium, and wherein the indices of refraction of said liquid crystal material and said containment medium are at least substantially matched to minimize distortion of light transmitted through an interface thereof.
Claim 21
Dependent Claim 10 words
A light control film comprising the apparatus of claim 9.
Claim 22
Dependent Claim 12 words
An optical shutter formed of the liquid crystal apparatus of claim 9.
Claim 23
Dependent Claim 28 words
The optical shutter of claim 18, said liquid crystal material comprising a layer of the same mounted with respect to a support through which light may be transmitted.
Claim 24
Dependent Claim 33 words
The shutter of claim 19, further comprising a support medium having light transmitting characteristics and said optical shutter being mounted with respect to said support medium to control the intensity of transmitted light.
Claim 25
Dependent Claim 28 words
The shutter of claim 21, said low birefringence encapsulated liquid crystal material being operative to control the intensity of light transmitted in both directions through said support medium.
Claim 26
Dependent Claim 24 words
The apparatus of claim 9, wherein said liquid crystal material controls the direction of said pleochroic dye without substantial scattering of light impinging thereon.
Claim 27
Dependent Claim 41 words
The apparatus of claim 9, said containment medium having an index of refraction, and wherein the difference between the index of refraction of said liquid crystal material and the index of refraction of said containment medium is about 0.03 or less.
Claim 28
Dependent Claim 13 words
The apparatus of claim 9, wherein said liquid crystal material is operationally nematic.
Claim 29
Dependent Claim 57 words
An optical apparatus comprising a low birefringence liquid crystal material in a containment medium, pleochroic dye in said liquid crystal material, said containment medium having an index of refraction, and the indices of refraction of said liquid crystal material and of said containment medium being substantially matched to minimize distortion of light transmitted through an interface thereof.
Claim 30
Dependent Claim 57 words
An optical apparatus comprising a low birefringence liquid crystal material in a containment medium, pleochroic dye in said liquid crystal material, said containment medium having an index of refraction, and the indices of refraction of said liquid crystal material and of said containment medium being substantially matched to minimize distortion of light transmitted through an interface thereof.
Claim 31
Dependent Claim 25 words
The apparatus of claim 21, said containment medium bounding a plurality of volumes for containing said liquid crystal material and forming therewith encapsulated liquid crystal.
Claim 32
Dependent Claim 15 words
The apparatus of claim 27, said containment medium and liquid crystal material forming an emulsion.
Claim 33
Dependent Claim 32 words
The apparatus of claim 27, wherein the difference between the index of refraction of said containment medium and the index of refraction of said liquid crystal material is about 0.03 or less.
Claim 34
Dependent Claim 12 words
The apparatus of claim 27, said containment medium being substantially optically transparent.
Claim 35
Dependent Claim 61 words
The apparatus of claim 27, said volumes having walls, and wherein said walls distort the natural structure of said liquid crystal material in the absence of an electric field, and wherein said dye aligns with respect to the structure of said liquid crystal material, whereby absorption of light by said dye is a function of alignment of the liquid crystal structure.
Claim 36
Dependent Claim 33 words
The apparatus of claim 31, further comprising electrode means for applying electric field to at least some of said liquid crystal material to effect generally parallel alignment thereof with respect to such field.
Claim 37
Dependent Claim 23 words
The apparatus of claim 32, further comprising circuit means for energizing said electrode means to apply such field to said liquid crystal material.
Claim 38
Dependent Claim 13 words
The apparatus of claim 27, wherein said liquid crystal material is operationally nematic.
Claim 39
Dependent Claim 35 words
The apparatus of claim 26, said liquid crystal material comprising a mixture of at least one liquid crystal material having one twist characteristic and at least one liquid crystal material having an opposite twist characteristic.
Claim 40
Dependent Claim 22 words
The apparatus of claim 35, wherein each of said liquid crystal materials is operationally nematic or the combination thereof is operationally nematic.
Claim 41
Dependent Claim 15 words
The apparatus of claim 35, each of said liquid crystal materials comprising a cholesterol derivative.
Claim 42
Dependent Claim 23 words
The apparatus of claim 35, at least one of said liquid crystal materials comprising cholesteryl chloride and at least one comprising cholesteryl oleate.
Claim 43
Dependent Claim 14 words
The apparatus of claim 35, one twist being lefthanded and the other being righthanded.
Claim 44
Dependent Claim 11 words
The apparatus of claim 35, said containment medium comprising polyvinyl alcohol.
Claim 45
Dependent Claim 33 words
The apparatus of claim 26, further comprising a support medium having light transmitting characteristics and said optical shutter being mounted with respect to said support medium to control the intensity of transmitted light.
Claim 46
Dependent Claim 28 words
The apparatus of claim 41, said low birefringence encapsulated liquid crystal material being operative to control the intensity of light transmitted in both directions through said support medium.
Claim 47
Dependent Claim 10 words
An optical shutter formed of the apparatus of claim 26.
Claim 48
Dependent Claim 28 words
The optical shutter of claim 43, said liquid crystal material comprising a layer of the same mounted with respect to a support through which light may be transmitted.
Claim 49
Dependent Claim 23 words
The optical shutter of claim 44, further comprising electrode means for applying an electric field across said layer of such liquid crystal material.
Claim 50
Dependent Claim 18 words
The shutter of claim 45, further comprising electrical circuit means for providing electrical power to said electrode means.
Claim 51
Dependent Claim 34 words
An electro-optical attenuator through which an image may be clearly viewed in all operational modes of said attenuator, comprising a low birefringence encapsulated liquid crystal material and pleochroic dye in said liquid crystal material.
Claim 52
Dependent Claim 34 words
An electro-optical attenuator through which an image may be clearly viewed in all operational modes of said attenuator, comprising a low birefringence encapsulated liquid crystal material and pleochroic dye in said liquid crystal material.
Claim 53
Dependent Claim 64 words
A light control apparatus comprising a low birefringence liquid crystal material, and a containment medium means for containing said liquid crystal material as encapsulated liquid crystal, said containment medium having an index of refraction, and wherein the difference between the index of refraction of said liquid crystal material and the index of refraction of said containment medium means is no greater than about 0.03.
Claim 54
Dependent Claim 64 words
A light control apparatus comprising a low birefringence liquid crystal material, and a containment medium means for containing said liquid crystal material as encapsulated liquid crystal, said containment medium having an index of refraction, and wherein the difference between the index of refraction of said liquid crystal material and the index of refraction of said containment medium means is no greater than about 0.03.
Claim 55
Independent Claim 63 words
A method of making a low birefringence liquid crystal material comprising mixing together at least one liquid crystal material having one twist characteristic and at least one liquid crystal material having an opposite twist characteristic, said mixing comprising mixing two cholesterol derivatives that function in an operationally nematic manner, one of such cholesterol derivatives comprising cholesteryl chloride and the other comprising cholesteryl oleate.
Claim 56
Independent Claim 63 words
A method of making a low birefringence liquid crystal material comprising mixing together at least one liquid crystal material having one twist characteristic and at least one liquid crystal material having an opposite twist characteristic, said mixing comprising mixing two cholesterol derivatives that function in an operationally nematic manner, one of such cholesterol derivatives comprising cholesteryl chloride and the other comprising cholesteryl oleate.
Claim 57
Independent Claim 99 words
A method of making a device for controlling light transmission with minimum distortion of the transmitted light, comprising selecting a liquid crystal material having a low birefringence characteristic and a containment medium having an index of refraction such that the difference between the indices of refraction of such liquid crystal material and such containment medium is no greater than about 0.03, mixing pleochroic dye with such low birefringence liquid crystal material, and mixing such low birefringence liquid crystal material containing pleochroic dye and an encapsulating medium to form plural capsule-like containment media containing such liquid crystal material and dye.
Claim 58
Independent Claim 99 words
A method of making a device for controlling light transmission with minimum distortion of the transmitted light, comprising selecting a liquid crystal material having a low birefringence characteristic and a containment medium having an index of refraction such that the difference between the indices of refraction of such liquid crystal material and such containment medium is no greater than about 0.03, mixing pleochroic dye with such low birefringence liquid crystal material, and mixing such low birefringence liquid crystal material containing pleochroic dye and an encapsulating medium to form plural capsule-like containment media containing such liquid crystal material and dye.
Claim 59
Dependent Claim 48 words
The method of claim 50, further comprising making said liquid crystal material by mixing at least two liquid crystal materials, one having one twist characteristic and one having an opposite twist characteristic, whereby such twist characteristic substantially cause a near zero effective twist characteristic for the combined material.
Claim 60
Dependent Claim 24 words
The method of claim 51, further comprising applying the overall mixture to a generally optically transmissive support for controlling light transmission through said support.
Claim 61
Independent Claim 63 words
A method of making an optical apparatus, comprising mixing a low birefringence liquid crystal material containing a pleochroic dye and a containment medium to form contained volumes of liquid crystal and pleochroic dye, and selecting said liquid crystal material and said containment medium such that the indices of refraction thereof are substantially matched to minimize distortion of light transmitted through an interface thereof.
Claim 62
Independent Claim 63 words
A method of making an optical apparatus, comprising mixing a low birefringence liquid crystal material containing a pleochroic dye and a containment medium to form contained volumes of liquid crystal and pleochroic dye, and selecting said liquid crystal material and said containment medium such that the indices of refraction thereof are substantially matched to minimize distortion of light transmitted through an interface thereof.
Claim 63
Independent Claim 53 words
A method of making a light control device of low birefringence liquid crystal material comprising mixing low birefringence liquid crystal material and an encapsulating medium to form an emulsion of capsule-like containment media containing discrete quantities of liquid crystal material, and adding pleochroic dye to the mixture of low birefringence liquid crystal material.
Claim 64
Independent Claim 53 words
A method of making a light control device of low birefringence liquid crystal material comprising mixing low birefringence liquid crystal material and an encapsulating medium to form an emulsion of capsule-like containment media containing discrete quantities of liquid crystal material, and adding pleochroic dye to the mixture of low birefringence liquid crystal material.
Claim 65
Dependent Claim 45 words
The method of claim 29, further comprising making a mixture of at least two liquid crystal materials, one having one twist characteristic and one having an opposite twist characteristic, whereby such twist characteristics substantially cause a near zero effective twist characteristic for the combined material.
Claim 66
Dependent Claim 18 words
The method of claim 55, further comprising applying the overall mixture to a support for controlling light transmission.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-12-02 1989-06-03 1989-12-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-12-02 1993-06-03 1993-12-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-12-02 1997-06-03 1997-12-03 $7700.00 Window Closed / Lapsed

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