Patent US4890902A successfully refreshed from Google Patents.
US4890902A
Expired / Lapsed
US
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Liquid crystal light modulating materials with selectable viewing angles
Assignee: Kent State University
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Filing: 1988-02-23
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Granted: 1990-01-02
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Expires: 2008-02-23
Abstract
Abstract A light modulating material comprising phase-separated microdroplets of liquid crystal in a light transmissive, synthetic resin matrix wherein the index of refraction np of the matrix is matched or mismatched to an index of refraction No of the liquid crystal optical axis of the microdroplets so that when the microdroplet director is aligned relative to a surface of the material, maximum transmission of light occurs at a selected oblique angle relative to the surface of the material or at a selected narrow angle about the perpendicular to the surface of the material. Such matching or mismatching of indices of refraction may be accompanied by phase separation in an external magnetic or electric field, or by shaping the liquid crystal microdroplet into an ovoid or the like during or after phase separation to align the microdroplet directors thereby endowing the material with a permanent and movable viewing angle. One or more sheets of the improved light modulating material may be incorporated into a window or an electrooptic display device to provide angularly discriminating windows or displays that are transparent or visible only at selected angles of view and that are opague at other angles of view.
Inventors
- 👤 J. William Doane
- 👤 Eugene P. Wenninger
- 👤 John West
- 👤 Bao-Gang Wu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:07
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/52; C09K19/54; C09K19/542; C09K19/544; G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1334; Y; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249994; Y10T428/249995; Y10T428/249997
Claims Analysis
Total Claims: 58
Claim 1
Independent Claim
152 words
In a light modulating material comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the liquid crystal being soluble in the matrix-providing composition and the microdroplets being formed spontaneously by phase separation therefrom, the improvement wherein the ratio of the ordinary index of refraction of the liquid crystal microdroplets to the index of refraction of the matrix has a value such that when the optical axes of the microdroplets are aligned perpendicular to the surface of the material, incident light is transmitted through the material through a narrow viewing-angle about the perpendicular to the surface or through a viewing-angle oblique to the surface or such that when the optical axes of the microdroplet are aligned oblique to the surface of the material, incident light is transmitted through the material at a viewing-angle oblique to the surface or is transmitted through a viewing-angle about the perpendicular to the surface.
Claim 2
Dependent Claim
152 words
In a light modulating material comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the liquid crystal being soluble in the matrix-providing composition and the microdroplets being formed spontaneously by phase separation therefrom, the improvement wherein the ratio of the ordinary index of refraction of the liquid crystal microdroplets to the index of refraction of the matrix has a value such that when the optical axes of the microdroplets are aligned perpendicular to the surface of the material, incident light is transmitted through the material through a narrow viewing-angle about the perpendicular to the surface or through a viewing-angle oblique to the surface or such that when the optical axes of the microdroplet are aligned oblique to the surface of the material, incident light is transmitted through the material at a viewing-angle oblique to the surface or is transmitted through a viewing-angle about the perpendicular to the surface.
Claim 3
Dependent Claim
43 words
The material of claim 1 wherein the ratio is greater than one so that when the optical axes of the microdroplets are aligned perpendicular to the surface of the material light is transmitted through a narrow viewing-angle about the perpendicular to the surface.
Claim 4
Dependent Claim
127 words
In a light modulating material comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the liquid crystal being soluble in the matrix-providing composition and the microdroplets being formed spontaneously by phase separation therefrom, the improvement wherein the ratio of the ordinary index of refraction of the liquid crystal microdroplets to the index of refraction of the matrix is less that one so that when the optical axes of the microdroplets are aligned perpendicular to the surface of the material light is transmitted through viewing-angles oblique to the surface or so that when the optical axes of the microdroplets are aligned at an oblique viewing-angle relative to the surface, light is transmitted through the material at a viewing-angle about the perpendicular to the surface.
Claim 5
Dependent Claim
127 words
In a light modulating material comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the liquid crystal being soluble in the matrix-providing composition and the microdroplets being formed spontaneously by phase separation therefrom, the improvement wherein the ratio of the ordinary index of refraction of the liquid crystal microdroplets to the index of refraction of the matrix is less that one so that when the optical axes of the microdroplets are aligned perpendicular to the surface of the material light is transmitted through viewing-angles oblique to the surface or so that when the optical axes of the microdroplets are aligned at an oblique viewing-angle relative to the surface, light is transmitted through the material at a viewing-angle about the perpendicular to the surface.
Claim 6
Dependent Claim
58 words
The material of claim 1 wherein the ratio is equal to about one and the optical axes of the microdroplets are aligned at an angle relative to the surface of the material, so that light is transmitted through the material at a viewing-angle that generally coincides with the angle of alignment of the optical axes of the microdroplets.
Claim 7
Dependent Claim
139 words
In a light modulating material comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the liquid crystal being soluble in the matrix-providing composition and the microdroplets being formed spontaneously by phase-separation therefrom, the improvement wherein the microdroplets are ellipsoidal with the long axes of the ellipses aligned at an angle oblique to the surface of the material, wherein the optical axes of the microdroplets are aligned generally with the long axes of the ellipses so that in the absence of an applied field light is transmitted through the material at a viewing-angle that generally coincides with the angle of alignment of the optical axes of the microdroplets, and wherein the optical axes of the microdroplets are movable by the application of an external field and the viewing-angle is movable along optical axes of the microdroplets.
Claim 8
Dependent Claim
139 words
In a light modulating material comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the liquid crystal being soluble in the matrix-providing composition and the microdroplets being formed spontaneously by phase-separation therefrom, the improvement wherein the microdroplets are ellipsoidal with the long axes of the ellipses aligned at an angle oblique to the surface of the material, wherein the optical axes of the microdroplets are aligned generally with the long axes of the ellipses so that in the absence of an applied field light is transmitted through the material at a viewing-angle that generally coincides with the angle of alignment of the optical axes of the microdroplets, and wherein the optical axes of the microdroplets are movable by the application of an external field and the viewing-angle is movable along optical axes of the microdroplets.
Claim 9
Dependent Claim
17 words
The material of claim 5 wherein the ratio is less than, equal to, or greater than one.
Claim 10
Dependent Claim
49 words
A light modulating material comprising at least two sheets of a light transmissive synthetic resin matrix containing dispersed microdroplets of liquid crystal wherein the effective index of refraction of the microdroplets in each sheet is different from the effective index of refraction of the microdroplets in an adjacent sheet.
Claim 11
Dependent Claim
49 words
A light modulating material comprising at least two sheets of a light transmissive synthetic resin matrix containing dispersed microdroplets of liquid crystal wherein the effective index of refraction of the microdroplets in each sheet is different from the effective index of refraction of the microdroplets in an adjacent sheet.
Claim 12
Dependent Claim
74 words
A light modulating material comprising at least two sheets of a light transmissive synthetic resin matrix containing dispersed microdroplets of liquid crystal wherein the ratio of the index of refraction of the synthetic resin matrix to the ordinary index of refraction of the microdroplets in one sheet differs from the ratio of the index of refraction of the synthetic resin matrix to the ordinary index of refraction of the microdroplets in an adjacent sheet.
Claim 13
Dependent Claim
74 words
A light modulating material comprising at least two sheets of a light transmissive synthetic resin matrix containing dispersed microdroplets of liquid crystal wherein the ratio of the index of refraction of the synthetic resin matrix to the ordinary index of refraction of the microdroplets in one sheet differs from the ratio of the index of refraction of the synthetic resin matrix to the ordinary index of refraction of the microdroplets in an adjacent sheet.
Claim 14
Dependent Claim
153 words
A window for selectively scattering away incident light and suitable for use in a vehicle or an architectural structure, the window comprising liquid crystal microdroplets dispersed in a light transmissive synthetic resin matrix, the microdroplets having their extraordinary indices of refraction aligned at a selected angle relative to a planar surface of the matrix, the liquid crystal being soluble in the matrix-forming composition and the microdroplets being formed spontaneously by phase separation therefrom, and the ordinary index of refraction of the microdroplets is deliberately mismatched relative to the index of refraction of the matrix by a selected amount to achieve an effective refractive index such that said material exhibits maximum transparency through a viewing angle which is one of a predetermined angle about a perpendicular to the surface or an angle oblique to the surface, while light incident on same surface at angles other than the viewing angle is primarily diffused or scattered.
Claim 15
Dependent Claim
153 words
A window for selectively scattering away incident light and suitable for use in a vehicle or an architectural structure, the window comprising liquid crystal microdroplets dispersed in a light transmissive synthetic resin matrix, the microdroplets having their extraordinary indices of refraction aligned at a selected angle relative to a planar surface of the matrix, the liquid crystal being soluble in the matrix-forming composition and the microdroplets being formed spontaneously by phase separation therefrom, and the ordinary index of refraction of the microdroplets is deliberately mismatched relative to the index of refraction of the matrix by a selected amount to achieve an effective refractive index such that said material exhibits maximum transparency through a viewing angle which is one of a predetermined angle about a perpendicular to the surface or an angle oblique to the surface, while light incident on same surface at angles other than the viewing angle is primarily diffused or scattered.
Claim 16
Dependent Claim
24 words
The window of claim 9 wherein the ordinary index of refraction of said microdroplets is greater than the index of refraction of said matrix.
Claim 17
Dependent Claim
24 words
The window of claim 9 wherein the ordinary index of refraction of said microdroplets is less than the index of refraction of said matrix.
Claim 18
Dependent Claim
123 words
A window for selectively scattering away incident light and suitable for use in a vehicle or an architectural structure, the window comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the microdroplets having their extraordinary indices of refraction aligned at a selected angle relative to a planar surface of the matrix, the liquid crystal being soluble in the matrix-forming composition, the microdroplets being formed spontaneously by phase separation therefrom, and the ordinary index of refraction of the matrix exceeding the refractive index of the microdroplet by a predetermined amount such that light that is incident on the window at a selected angle will be transmitted through the window while incident light at other angles will be diffused or scattered.
Claim 19
Dependent Claim
123 words
A window for selectively scattering away incident light and suitable for use in a vehicle or an architectural structure, the window comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the microdroplets having their extraordinary indices of refraction aligned at a selected angle relative to a planar surface of the matrix, the liquid crystal being soluble in the matrix-forming composition, the microdroplets being formed spontaneously by phase separation therefrom, and the ordinary index of refraction of the matrix exceeding the refractive index of the microdroplet by a predetermined amount such that light that is incident on the window at a selected angle will be transmitted through the window while incident light at other angles will be diffused or scattered.
Claim 20
Dependent Claim
18 words
The window of claim 12 wherein the extraordinary indices of said microdroplets are aligned perpendicular to said surface.
Claim 21
Dependent Claim
23 words
The window of claim 12 where the extraordinary indices of refraction of said microdroplets are aligned at an oblique angle to said surface.
Claim 22
Dependent Claim
126 words
A window for selectively scattering away incident light and suitable for use in a vehicle or an architectural structure, the window comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the microdroplets having their extraordinary indices of refraction aligned at a selected angle relative to a planar surface of the matrix, the liquid crystal being soluble in the matrix-forming composition and the microdroplets being formed spontaneously by phase separation therefrom, and the ordinary index of refraction of the microdroplets being less than the refractive index of the matrix by a predetermined amount such that light that is incident on the window at a selected angle will be transmitted through the window while incident light at other angles will be diffused or scattered.
Claim 23
Dependent Claim
126 words
A window for selectively scattering away incident light and suitable for use in a vehicle or an architectural structure, the window comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the microdroplets having their extraordinary indices of refraction aligned at a selected angle relative to a planar surface of the matrix, the liquid crystal being soluble in the matrix-forming composition and the microdroplets being formed spontaneously by phase separation therefrom, and the ordinary index of refraction of the microdroplets being less than the refractive index of the matrix by a predetermined amount such that light that is incident on the window at a selected angle will be transmitted through the window while incident light at other angles will be diffused or scattered.
Claim 24
Dependent Claim
18 words
The window of claim 15 wherein the extraordinary indices of said microdroplets are aligned perpendicular to said surface.
Claim 25
Dependent Claim
23 words
The window of claim 15 where the extraordinary indices of refraction of said microdroplets are aligned at an oblique angle to said surface.
Claim 26
Dependent Claim
62 words
A window for selectively scattering away incident light and suitable for use in a vehicle or an architectural structure comprising two sheets of a light transmissive synthetic resin matrix containing dispersed microdroplets of liquid crystal wherein the effective index of refraction of the microdroplets in each sheet is different from the effective index of refraction of the microdroplets in an adjacent sheet.
Claim 27
Dependent Claim
62 words
A window for selectively scattering away incident light and suitable for use in a vehicle or an architectural structure comprising two sheets of a light transmissive synthetic resin matrix containing dispersed microdroplets of liquid crystal wherein the effective index of refraction of the microdroplets in each sheet is different from the effective index of refraction of the microdroplets in an adjacent sheet.
Claim 28
Dependent Claim
87 words
A window for selectively scattering away incident light and suitable for use in a vehicle or an architectural structure comprising two sheets of a light transmissive synthetic resin matrix containing dispersed microdroplets of liquid crystal wherein the ratio of the index of refraction of the synthetic resin matrix to the ordinary index of refraction of the microdroplets in one sheet differs from the ratio of the index of refraction of the synthetic resin matrix to the ordinary index of refraction of the microdroplets in an adjacent sheet.
Claim 29
Dependent Claim
87 words
A window for selectively scattering away incident light and suitable for use in a vehicle or an architectural structure comprising two sheets of a light transmissive synthetic resin matrix containing dispersed microdroplets of liquid crystal wherein the ratio of the index of refraction of the synthetic resin matrix to the ordinary index of refraction of the microdroplets in one sheet differs from the ratio of the index of refraction of the synthetic resin matrix to the ordinary index of refraction of the microdroplets in an adjacent sheet.
Claim 30
Dependent Claim
154 words
In a method of making a light modulating material comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the liquid crystal being soluble in the matrix-providing composition and the microdroplets being formed spontaneously by phase separation therefrom, the improvement comprising the step of adjusting the ratio of the ordinary index of refraction of the liquid crystal microdroplets to the index of refraction of the matrix to a value such that when the microdroplet directors are aligned perpendicular to the surface of the material, incident light is transmitted through the material through a narrow viewing-angle about the perpendicular to the surface or through a viewing-angle oblique to the surface or such that when the microdroplet directors are aligned oblique to the surface of the material, incident light is transmitted through the material at a viewing-angle oblique to the surface or is transmitted through a viewing-angle about the perpendicular to the surface.
Claim 31
Dependent Claim
154 words
In a method of making a light modulating material comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the liquid crystal being soluble in the matrix-providing composition and the microdroplets being formed spontaneously by phase separation therefrom, the improvement comprising the step of adjusting the ratio of the ordinary index of refraction of the liquid crystal microdroplets to the index of refraction of the matrix to a value such that when the microdroplet directors are aligned perpendicular to the surface of the material, incident light is transmitted through the material through a narrow viewing-angle about the perpendicular to the surface or through a viewing-angle oblique to the surface or such that when the microdroplet directors are aligned oblique to the surface of the material, incident light is transmitted through the material at a viewing-angle oblique to the surface or is transmitted through a viewing-angle about the perpendicular to the surface.
Claim 32
Dependent Claim
44 words
The method of claim 20 wherein the ratio is adjusted to a value greater than one so that when the microdroplet directors are aligned perpendicular to the surface of the material light is transmitted through a narrow viewing-angle about the perpendicular to the surface.
Claim 33
Dependent Claim
72 words
The method of claim 20 wherein the ratio is adjusted to a value less than one so that when the microdroplet directors are aligned perpendicular to the surface of the material light is transmitted through a viewing-angle oblique to the surface or so that when the microdroplets are aligned at an oblique viewing-angle relative to the surface, light is transmitted through the material at a viewing-angle about the perpendicular to the surface.
Claim 34
Dependent Claim
60 words
The method of claim 20 wherein the ratio is adjusted to a value equal to about one and including the further step of aligning the microdroplet directors at an angle relative to the surface of the material, so that light is transmitted through the material at a viewing-angle that generally coincides with the angle of alignment of the microdroplet directors.
Claim 35
Dependent Claim
79 words
The method of claim 20 including the further step of forming the microdroplets into ellipsoidal shapes with the long axes of the ellipses aligned at an angle oblique to the surface of the material, so that in the absence of an applied field the microdroplet directors are aligned generally with the long axes of the ellipses and incident light is transmitted through the material at a viewing-angle that generally coincides with the angle of alignment of the microdroplet directors.
Claim 36
Dependent Claim
22 words
The method of claim 24 wherein the ratio is adjusted to a value of less than, equal to, or greater than one.
Claim 37
Dependent Claim
135 words
In a method of making a light modulating material comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the liquid crystal being soluble in the matrix-forming composition and the microdroplets being formed spontaneously by phase separation therefrom, the improvement comprising the steps of determining a maximum viewing angle through which light incident to a planar surface of said-material passes through said material, while incident light at other angles is primarily diffused or scattered, and deliberately mismatching the ordinary index of refraction of said microdroplets relative to the index of refraction of said matrix by a selected amount that results in an effective refractive index such that said maximum viewing angle is achieved when the extraordinary indices of refraction of the microdroplets are aligned at a selected angle relative to said surface.
Claim 38
Dependent Claim
135 words
In a method of making a light modulating material comprising microdroplets of liquid crystal dispersed in a light transmissive synthetic resin matrix, the liquid crystal being soluble in the matrix-forming composition and the microdroplets being formed spontaneously by phase separation therefrom, the improvement comprising the steps of determining a maximum viewing angle through which light incident to a planar surface of said-material passes through said material, while incident light at other angles is primarily diffused or scattered, and deliberately mismatching the ordinary index of refraction of said microdroplets relative to the index of refraction of said matrix by a selected amount that results in an effective refractive index such that said maximum viewing angle is achieved when the extraordinary indices of refraction of the microdroplets are aligned at a selected angle relative to said surface.
Claim 39
Dependent Claim
36 words
The method of claim 26 wherein the step of deliberately mismatching comprises selecting a liquid crystal such that the ordinary index of refraction of said microdroplets is greater than the index of refraction of said matrix.
Claim 40
Dependent Claim
36 words
The method of claim 26 wherein the step of deliberately mismatching comprises selecting a liquid crystal such that the ordinary index of refraction of said microdroplets is less than the index of refraction of said matrix.
Claim 41
Dependent Claim
20 words
The method of claim 26 including the step of aligning the extraordinary indices of said microdroplets perpendicular to said surface.
Claim 42
Dependent Claim
25 words
The method of claim 26 including the step of aligning the extraordinary indices of refraction of said microdroplets at an oblique angle to said surface.
Claim 43
Independent Claim
132 words
A method of making a light modulating material comprising microdroplets of liquid crystal having positive dielectric anisotropy dispersed in a light transmissive synthetic resin matrix, said liquid crystal being soluble in the matrix-forming composition and said microdroplets being formed spontaneously by phase separation therefrom, the improvement comprising the step of deliberately mismatching the ordinary index of refraction of said microdroplets relative to the index of refraction of said matrix by a selected amount in order to achieve an effective refractive index such that when the extraordinary indices of refraction of the microdroplets are aligned at a selected angle relative to a planar surface of said material light incident to said surface at a predetermined maximum viewing angle passes through said material, while light at other incident angles is primarily diffused or scattered.
Claim 44
Independent Claim
132 words
A method of making a light modulating material comprising microdroplets of liquid crystal having positive dielectric anisotropy dispersed in a light transmissive synthetic resin matrix, said liquid crystal being soluble in the matrix-forming composition and said microdroplets being formed spontaneously by phase separation therefrom, the improvement comprising the step of deliberately mismatching the ordinary index of refraction of said microdroplets relative to the index of refraction of said matrix by a selected amount in order to achieve an effective refractive index such that when the extraordinary indices of refraction of the microdroplets are aligned at a selected angle relative to a planar surface of said material light incident to said surface at a predetermined maximum viewing angle passes through said material, while light at other incident angles is primarily diffused or scattered.
Claim 45
Dependent Claim
97 words
A light modulating material comprising liquid crystal microdroplets dispersed in a resin matrix having a generally planar surface, said microdroplets being formed by phase separation and having their optical axes prealigned in a first direction oblique to said surface in the absence of an aligning field, and said material being responsive to an aligning field having a second direction relative to said surface so that the prealigned optical axes of said microdroplets are caused to rotate from said first direction toward said second direction, thereby changing the viewing angle at which light is transmitted through said material.
Claim 46
Dependent Claim
97 words
A light modulating material comprising liquid crystal microdroplets dispersed in a resin matrix having a generally planar surface, said microdroplets being formed by phase separation and having their optical axes prealigned in a first direction oblique to said surface in the absence of an aligning field, and said material being responsive to an aligning field having a second direction relative to said surface so that the prealigned optical axes of said microdroplets are caused to rotate from said first direction toward said second direction, thereby changing the viewing angle at which light is transmitted through said material.
Claim 47
Dependent Claim
73 words
The light modulating material of claim 32 wherein the ordinary index of refraction n o of said liquid crystal microdroplets is matched to the index of refraction n p of said matrix so that maximum transparency to light incident upon said surface is in said first direction of prealignment of said optical axes, and said material having the characteristic of exhibiting different angles of maximum transparency for different magnitudes of said aligning field.
Claim 48
Dependent Claim
32 words
The material of claim 32 or claim 33 wherein said optical axes of said microdroplets are prealigned by one of: (a) mechanical shear, (b) an electric field, or (c) a magnetic field.
Claim 49
Dependent Claim
127 words
A light modulating device comprising: a light modulating material formed by liquid crystal microdroplets dispersed in a light transmissive resin matrix having a generally planar surface, said liquid crystal microdroplets being formed by phase separation and having their optical axes prealigned in a first direction oblique to said surface; electrodes adjacent said surface of said material; and means for applying a voltage to said electrodes to establish an electric field in said material in a direction perpendicular to said surface so as to rotate the direction of alignment of said optical axes closer to said perpendicular direction in proportion to said voltage, whereby the direction of transparency for light incident upon said surface is controlled by said voltage and approaches said perpendicular direction as said voltage increases.
Claim 50
Dependent Claim
127 words
A light modulating device comprising: a light modulating material formed by liquid crystal microdroplets dispersed in a light transmissive resin matrix having a generally planar surface, said liquid crystal microdroplets being formed by phase separation and having their optical axes prealigned in a first direction oblique to said surface; electrodes adjacent said surface of said material; and means for applying a voltage to said electrodes to establish an electric field in said material in a direction perpendicular to said surface so as to rotate the direction of alignment of said optical axes closer to said perpendicular direction in proportion to said voltage, whereby the direction of transparency for light incident upon said surface is controlled by said voltage and approaches said perpendicular direction as said voltage increases.
Claim 51
Dependent Claim
122 words
A light modulating material comprising at least two sheets stacked face-to-face, each of said sheets comprising a resin matrix containing microdroplets of liquid crystal dispersed in said matrix, said microdroplets being formed by phase separation from a solution of liquid crystal and resin upon solidifying of said resin, said material being characterized in that the ratio of the index of refraction of said matrix to the ordinary index of refraction of said microdroplets in one sheet differs from the corresponding ratio in the other sheet, whereby each of said sheets exhibits a different angle of transparency to light incident upon the face thereof, said material exhibiting an overall angle of transparency lying between the different angles of transparency of said two sheets.
Claim 52
Dependent Claim
122 words
A light modulating material comprising at least two sheets stacked face-to-face, each of said sheets comprising a resin matrix containing microdroplets of liquid crystal dispersed in said matrix, said microdroplets being formed by phase separation from a solution of liquid crystal and resin upon solidifying of said resin, said material being characterized in that the ratio of the index of refraction of said matrix to the ordinary index of refraction of said microdroplets in one sheet differs from the corresponding ratio in the other sheet, whereby each of said sheets exhibits a different angle of transparency to light incident upon the face thereof, said material exhibiting an overall angle of transparency lying between the different angles of transparency of said two sheets.
Claim 53
Dependent Claim
184 words
A light modulating device comprising: a light modulating material comprising liquid crystal microdroplets dispersed in a light transmissive resin matrix having a generally planar surface, said liquid crystal microdroplets being formed by phase separation and having their optical axes prealigned in a first direction oblique to said surface in the absence of an aligning field, and said material being responsive to an aligning field having a second direction relative to said surface so that the prealigned optical axes of said microdroplets are caused to rotate from said first direction toward said second direction, thereby changing the viewing angle at which light is transmitted through said material; electrodes adjacent said surface of said material; and means for applying a voltage to said electrode means to establish an electric field in said material in a direction perpendicular to said surface so as to rotate the direction of alignment of said optical axes closer to said perpendicular in proportion to said voltage whereby the direction of transparency for light incident upon said surface is controlled by said voltage and approaches said perpendicular direction as said voltage increases.
Claim 54
Dependent Claim
184 words
A light modulating device comprising: a light modulating material comprising liquid crystal microdroplets dispersed in a light transmissive resin matrix having a generally planar surface, said liquid crystal microdroplets being formed by phase separation and having their optical axes prealigned in a first direction oblique to said surface in the absence of an aligning field, and said material being responsive to an aligning field having a second direction relative to said surface so that the prealigned optical axes of said microdroplets are caused to rotate from said first direction toward said second direction, thereby changing the viewing angle at which light is transmitted through said material; electrodes adjacent said surface of said material; and means for applying a voltage to said electrode means to establish an electric field in said material in a direction perpendicular to said surface so as to rotate the direction of alignment of said optical axes closer to said perpendicular in proportion to said voltage whereby the direction of transparency for light incident upon said surface is controlled by said voltage and approaches said perpendicular direction as said voltage increases.
Claim 55
Independent Claim
140 words
A method of making a light modulating material containing liquid crystal microdroplets dispersed in a light transmissive resin matrix having a generally planar surface, said microdroplets being formed by phase separation, said material having an optimum viewing angle oblique to the surface of said material wherein the material exhibits maximum transparency, said method comprising the steps of: establishing said optimum viewing angle oblique to the surface of said material; selecting a liquid crystal having an ordinary index of refraction, n o , which is related to the index of refraction of the matrix, n p , such that said material exhibits the optimum viewing angle when the optical axes of the microdroplets are aligned in a selected direction relative to the surface of said material; and forming the liquid crystal microdroplets in said light transmissive resin matrix by phase separation.
Claim 56
Independent Claim
140 words
A method of making a light modulating material containing liquid crystal microdroplets dispersed in a light transmissive resin matrix having a generally planar surface, said microdroplets being formed by phase separation, said material having an optimum viewing angle oblique to the surface of said material wherein the material exhibits maximum transparency, said method comprising the steps of: establishing said optimum viewing angle oblique to the surface of said material; selecting a liquid crystal having an ordinary index of refraction, n o , which is related to the index of refraction of the matrix, n p , such that said material exhibits the optimum viewing angle when the optical axes of the microdroplets are aligned in a selected direction relative to the surface of said material; and forming the liquid crystal microdroplets in said light transmissive resin matrix by phase separation.
Claim 57
Dependent Claim
183 words
A light modulating device comprising: a light modulating material formed by liquid crystal microdroplets dispersed in a light transmissive resin matrix having a generally planar surface and the ordinary index of refraction, n o , of the microcrystal being equal to or greater than the index of refraction of the matrix, n p , said liquid crystal microdroplets being formed by phase separation, said resin being solidified in the presence of an aligning field having a direction and a magnitude sufficient to align the optical axes of said microdroplets in a direction oblique to said surface so that said optical axes remain aligned in said oblique direction upon removal of said aligning field; electrode adjacent said surface of said material; and means for applying a voltage to said electrode means to establish an electric field in said material in a direction perpendicular to said surface so as to rotate the direction of alignment of said optical axes closer to said perpendicular direction in proportion to said voltage, whereby the direction of transparency for light incident upon said surface is controlled by said voltage.
Claim 58
Dependent Claim
183 words
A light modulating device comprising: a light modulating material formed by liquid crystal microdroplets dispersed in a light transmissive resin matrix having a generally planar surface and the ordinary index of refraction, n o , of the microcrystal being equal to or greater than the index of refraction of the matrix, n p , said liquid crystal microdroplets being formed by phase separation, said resin being solidified in the presence of an aligning field having a direction and a magnitude sufficient to align the optical axes of said microdroplets in a direction oblique to said surface so that said optical axes remain aligned in said oblique direction upon removal of said aligning field; electrode adjacent said surface of said material; and means for applying a voltage to said electrode means to establish an electric field in said material in a direction perpendicular to said surface so as to rotate the direction of alignment of said optical axes closer to said perpendicular direction in proportion to said voltage, whereby the direction of transparency for light incident upon said surface is controlled by said voltage.
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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) | 1993-01-01 | 1993-07-03 | 1994-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-01 | 1997-07-03 | 1998-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-01 | 2001-07-03 | 2002-01-02 | $7700.00 | Window Closed / Lapsed |