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US5202677A Expired / Lapsed US ⏱️ 0.0 years remaining

Display apparatus using thermochromic material

Assignee: CRYSTAL IMAGES Inc A CORP OF NV
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Filing: 1991-01-31
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Granted: 1993-04-13
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Expires: 2011-01-31
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Abstract

Abstract A visual display dependent upon the use of thermochromic materials is formed as a thin structure on a substrate sheet with a vapor deposited conductive film heater applied thereto. The current is applied to the heater through parallel opposed buss bars so that the heater heats uniformly. A non-thermochromic image layer is mounted on the substrate, with one or more thermochromic image layers thereover. One thermochromic image layer covers a first portion of a visible display area of the substrate, while a second thermochromic layer covers a second portion of the visible display area, with the first and second portions overlapping slightly along contiguous edges thereof. As the display is heated and cooled, the thermochromic materials of the thermochromic image layers reach their respective transition temperatures to change state from opaque to colorless or vice-versa, or from one color to another. The visual display is mounted within an enclosure to protect the display from environmental interference and thereby insure the desired control of heating of the display, as well as cooling thereof.

Inventors

  • 👤 Robert Parker
  • 👤 Stephen Phillips

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 06:31
CPC Classifications
G; G09; G09F; G09F9/00; G01; G01K; G01K11/00; G01K11/12; G02; G02F; G02F1/00; G02F1/01; G02F1/0147; B; B41; B41M; B41M5/00; B41M5/26; B41M5/30; B41M5/305

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 196 words
A visual display apparatus comprising: a substrate having a visible display area; means for controlling the temperature of the visible display area of the substrate; a first thermochromic material covering a first portion of the visible display area, the first thermochromic material changing, as a result of a first temperature change, from a first colored state to a second generally transparent state; and a second thermochromic material covering a second portion of the visible display area, the second thermochromic material changing as a result of a second temperature change, from a first colored state to a second generally transparent state, wherein the first and second thermochromic materials combine to form a substantially single thermochromic layer on the visible display area of the substrate, wherein one of the first and second portions defines, at least in part, a positive representation of a desired display image and the other one of the first and second portions defines, at least in part, a negative representation of the same desired display image at the same place on the visible display area, and wherein the first and second thermochromic materials have the same color when in their respective first colored states.
Claim 2
Dependent Claim 196 words
A visual display apparatus comprising: a substrate having a visible display area; means for controlling the temperature of the visible display area of the substrate; a first thermochromic material covering a first portion of the visible display area, the first thermochromic material changing, as a result of a first temperature change, from a first colored state to a second generally transparent state; and a second thermochromic material covering a second portion of the visible display area, the second thermochromic material changing as a result of a second temperature change, from a first colored state to a second generally transparent state, wherein the first and second thermochromic materials combine to form a substantially single thermochromic layer on the visible display area of the substrate, wherein one of the first and second portions defines, at least in part, a positive representation of a desired display image and the other one of the first and second portions defines, at least in part, a negative representation of the same desired display image at the same place on the visible display area, and wherein the first and second thermochromic materials have the same color when in their respective first colored states.
Claim 3
Dependent Claim 24 words
The apparatus of claim 1 wherein the temperature varying means comprises: a vapor deposited heater element on the visible display area of the substrate.
Claim 4
Dependent Claim 22 words
The apparatus of claim 2, wherein the temperature controlling means further comprises: means for applying an electrical current to the heater element.
Claim 5
Dependent Claim 42 words
The apparatus of claim 3 wherein the current applying means includes a pair of spaced apart, highly conductive buss bars mounted on the heater element for uniformly distributing the current to the heater element on the visible display area of the substrate.
Claim 6
Dependent Claim 12 words
The application of claim 1 wherein the substrate is a thin sheet.
Claim 7
Dependent Claim 28 words
The apparatus of claim 1 wherein the first and second temperature changes are defined by sequential increases in the temperature of the visual display area of the substrate.
Claim 8
Dependent Claim 28 words
The apparatus of claim 1, and further comprising: a non-thermochromic image layer aligned within the image display area between the substrate and the first and second thermochromic materials.
Claim 9
Dependent Claim 36 words
The apparatus of claim 1, and further comprising: a non-thermochromic image layer aligned within the image display area and over at least one of the thermochromic materials to cover a portion of the visible display area.
Claim 10
Dependent Claim 49 words
The apparatus of claim 1, and further comprising: a thermally activated material mounted over at least a portion of either the first portion or second portion of the visible display area, with the thermally activated material becoming optically active over the visible range only within a desired temperature range.
Claim 11
Dependent Claim 29 words
The apparatus of claim 9 wherein the thermochromic materials are generally dark when in their respective first colored states, and wherein the thermally active material is a liquid crystal.
Claim 12
Dependent Claim 36 words
The apparatus of claim 9 wherein the first and second temperature changes are defined by sequential increases in temperature, and wherein the desired temperature range has its highest temperature point spaced below the first temperature change.
Claim 13
Dependent Claim 46 words
The apparatus of claim 1 wherein the temperature controlling means includes a control system for reversibly changing the temperature of the visible display area of the substrate from a base temperature below the first temperature change up to a maximum temperature above the second temperature change.
Claim 14
Dependent Claim 12 words
The apparatus of claim 1 wherein the thermochromic materials comprise thermochromic inks.
Claim 15
Dependent Claim 156 words
The apparatus of claim 1, and further comprising: a third thermochromic material covering a third portion of the visible display area, the third thermochromic material changing, as a result of a third temperature change, from a first colored state to a second generally transparent state, with the third temperature change occurring between the first and second temperature changes as the temperature of the visual display area of the substrate is changed, wherein the first, second and third thermochromic materials combine to form a substantially single thermochromic layer on the visible display area of the substrate, wherein the third portion defines either a positive or negative representation of a desired display image and the second portion defines an opposite representation of the same desired display image at the same place on the visible display area, and wherein the first, second and third thermochromic materials have essentially the same visual densities when in their respective first colored states.
Claim 16
Dependent Claim 18 words
The apparatus of claim 14 wherein the second and third thermochromic materials overlap slightly along contiguous edges thereof.
Claim 17
Dependent Claim 18 words
The apparatus of claim 1 wherein the first and second thermochromic materials overlap slightly along contiguous edges thereof.
Claim 18
Dependent Claim 19 words
The apparatus of claim 16 wherein the first and second thermochromic materials overlap by no more than 0.020 inch.
Claim 19
Dependent Claim 214 words
A visual display apparatus comprising: a substrate having a visible display area; means for controlling the temperature of the visible display area of the substrate; a first thermochromic material covering a first portion of the visible display area, the first thermochromic material changing, as a result of a first temperature change, from a first colored state to a second generally transparent state; and a second thermochromic material covering a second portion of the visible display area, the second thermochromic material changing as a result of a second temperature change, from a first colored state to a second generally transparent state, wherein the first and second thermochromic materials combine to form a substantially single thermochromic layer on the visible display area of the substrate, wherein one of the first and second portions defines, at least in part, a positive representation of a desired display image and the other one of the first and second portions defines, at least in part, a negative representation of the same desired display image at the same place on the visible display area, and wherein the first and second thermochromic materials both have the same general opaque visual density when in their respective first wavelength transmission states and both are generally colorless when in their respective second wavelength transmission states.
Claim 20
Dependent Claim 214 words
A visual display apparatus comprising: a substrate having a visible display area; means for controlling the temperature of the visible display area of the substrate; a first thermochromic material covering a first portion of the visible display area, the first thermochromic material changing, as a result of a first temperature change, from a first colored state to a second generally transparent state; and a second thermochromic material covering a second portion of the visible display area, the second thermochromic material changing as a result of a second temperature change, from a first colored state to a second generally transparent state, wherein the first and second thermochromic materials combine to form a substantially single thermochromic layer on the visible display area of the substrate, wherein one of the first and second portions defines, at least in part, a positive representation of a desired display image and the other one of the first and second portions defines, at least in part, a negative representation of the same desired display image at the same place on the visible display area, and wherein the first and second thermochromic materials both have the same general opaque visual density when in their respective first wavelength transmission states and both are generally colorless when in their respective second wavelength transmission states.
Claim 21
Dependent Claim 28 words
The apparatus of claim 18 wherein the first and second temperature changes are defined by sequential increases in the temperature of the visual display area of the substrate.
Claim 22
Dependent Claim 46 words
The apparatus of claim 18 wherein the temperature controlling means includes a control system for reversibly changing the temperature of the visible display area of the substrate from a base temperature below the first temperature change up to a maximum temperature above the second temperature change.
Claim 23
Dependent Claim 12 words
The apparatus of claim 18 wherein the thermochromic materials comprise thermochromic inks.
Claim 24
Dependent Claim 18 words
The apparatus of claim 18 wherein the first and second thermochromic materials overlap slightly along contiguous edges thereof.
Claim 25
Dependent Claim 40 words
The visual display apparatus of claim 18 wherein the substrate is a thin sheet, and further comprising: enclosure means about the sheet for protecting the sheet and for reducing environmental interference with a desired thermal operation of the display apparatus.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-04-12 1996-10-12 1997-04-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-04-12 2000-10-12 2001-04-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-04-12 2004-10-12 2005-04-13 $7700.00 Window Closed / Lapsed

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