`Sanelle et al.
`
`USOO6181394B1
`(10) Patent No.:
`US 6,181,394 B1
`(45) Date of Patent:
`Jan. 30, 2001
`
`(54) SUPER BRIGHT LOW REFLECTION LIQUID
`CRYSTAL DISPLAY
`(75) Inventors: Joseph J. Sanelle; Diggy R. Breiling,
`both of Westboro, MA (US)
`(73) Assignee: White Electronic Designs, Corp.,
`Phoenix, AZ (US)
`
`(*) Notice:
`
`Under 35 U.S.C. 154(b), the term of this
`patent shall be extended for 0 days.
`
`(56)
`
`s
`
`Primary Examiner William L. Sikes
`Assistant Examiner Tai V. Duong
`(74) Attorney, Agent, or Firm-Kriegsman & Kriegsman
`(57)
`ABSTRACT
`A liquid crystal display (LCD) exhibiting enhanced optical
`Viewing performance. In a preferred embodiment, the LCD
`comprises a first glass Substrate, a Second glass Substrate and
`an active matrix liquid crystal display (AMLCD) panel. The
`LCD also comprises a rear polarizer adhered to the rear of
`the AMLCD panel with an index-matched, pressure Sensi
`tive adhesive (PSA). The LCD further comprises an indium
`(21) Appl. No.: 09/235,584
`tin oxide coating adapted for use as a heating element, the
`coating being applied to the front of the Second glass
`(22) Filed:
`Jan. 22, 1999
`Substrate. The heating element is also adhered to the rear
`(51) Int. Cl." ........................ G02F1/1335; G02F 1/1343
`polarizer with a Silicone-based, index-matched, optical
`(52) U.S. Cl. ............................ 349/96; 349/122; 34.9/139;
`34.9/137; 349/158; 349/161 St. material. In i. th LCD comprises ity
`tin Oxide coating usable as an electromagnetic interference
`(58) Field of Search ...349,161,40.
`15, (EMI) shield, the coating being applied to the rear of the first
`s
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`s
`glass substrate. The EMI shield is also adhered to the front
`References Cited
`of the AMLCD panel with the above-mentioned silicone
`based bonding material. The LCD also comprises a front
`U.S. PATENT DOCUMENTS
`polarizer crossed relative to the rear polarizer. The front
`:
`polarizer is adhered to the front of the first glass substrate by
`: : E. Real".- - - - - - - - - - - - - - - - -r SE the above-mentioned Silicone-based bonding material. The
`5.430.607
`7/1995 Smith ....................
`... 361/683
`LCD additionally comprises a third glass substrate bonded
`5,523,873 * 6/1996 Bradford, III et al. .............. 349/139
`to the front of the front polarizer by the above-mentioned
`index-matched PSA. The LCD further includes an anti
`5,570.214
`10/1996 Abileah et al..
`reflection coating applied to the front of the third glass
`5,594,568
`1/1997 Abileah et al. .
`substrate. The LCD also includes a backlight positioned
`5,706,068
`1/1998 Abileah et al..
`5,739,881
`4/1998 Xu et al..
`behind the Second glass Substrate.
`5,818,559
`10/1998 Yoshida .................................. 349/96
`* cited by examiner
`
`19 Claims, 1 Drawing Sheet
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`Page 1 of 7
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`Tianma Exhibit 1012
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`U.S. Patent
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`Jan. 30, 2001
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`US 6,181,394 B1
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`1
`SUPER BRIGHT LOW REFLECTION LIQUID
`CRYSTAL DISPLAY
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`US 6,181,394 B1
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`normally incident visible wavelength of light passing there
`through in an amount of about 80-100. The device also
`comprises a rear, light-entrance polarizer having a transmis
`Sion axis oriented in a first direction, a front, light-exit
`polarizer having a transmission axis oriented in a Second
`direction with respect to the first direction thereby to define
`a normally white display, a rear retardation film disposed
`between the rear polarizer and the twisted nematic liquid
`crystal material, and a front retardation film disposed
`between the front polarizer and the liquid crystal material.
`The transmission axes of the retardation films are So
`arranged each with respect to the others So as to achieve a
`white light contrast ratio of at least about 10:1 over a
`horizontal angular span of at least about 100 and over a
`vertical angular span of greater than about 55.
`In U.S. Pat. No. 5,594,568, inventors Abileah et al., which
`issued Jan. 14, 1997, and which is incorporated herein by
`reference, there is disclosed a normally white liquid crystal
`display comprising a rear, light-entrance polarizer having a
`transmission axis oriented in a first direction; a front, light
`exit polarizer having a transmission axis oriented in a Second
`direction with respect to the first direction So as to define a
`normally white display; a twisted nematic liquid crystal
`layer; and first and Second positively birefringent uniaxial
`retardation films both disposed between the twisted nematic
`liquid crystal layer and one of the rear, light-entrance
`polarizer and the front, light-exit polarizer. The liquid crystal
`layer in the off State twists at least one normally incident
`visible wavelength of light less than about 110 as it passes
`therethrough, and the first and Second uniaxial retardation
`films have retardation values of from about 80-200 nm. The
`transmission axes of the polarizers and optical axes of the
`retardation films are So arranged each with respect to the
`otherS So as to achieve high contrast ratioS over a large range
`of predetermined Viewing angles.
`In U.S. Pat. No. 5,706,068, inventors Abileah et al., which
`issued Jan. 6, 1998, and which is incorporated herein by
`reference, there is disclosed a liquid crystal display com
`prising a plurality of pixels, each of the pixels being com
`prised of a pair of driving electrodes and a twisted nematic
`liquid crystal material located therebetween. The liquid
`crystal material is of a thickness “d” and has an anistrophy
`AN such that the product of d'AN is about 400–550 nm, and
`the liquid crystal material is capable of twisting at least one
`normally incident visible wavelength of light passing there
`through in an amount of about 800-100. The device also
`comprises a rear, light-entrance polarizer having a transmis
`Sion axis oriented in a first direction, a front, light-exit
`polarizer having a transmission axis oriented in a Second
`direction with respect to the first direction thereby to define
`a normally white display, a rear retardation film disposed
`between the rear polarizer and the twisted nematic liquid
`crystal material, and a front retardation film disposed
`between the front polarizer and the liquid crystal material.
`The transmission axes of the retardation films are So
`arranged each with respect to the others So as to achieve a
`white light contrast ratio of at least about 10:1 over a
`horizontal angular span of at least about 100 and over a
`vertical angular span of greater than about 55.
`In U.S. Pat. No. 5,739,881, inventors Xu et al., which
`issued Apr. 14, 1998, and which is incorporated herein by
`reference, there is disclosed a normally white twisted nem
`atic liquid crystal display comprising a liquid crystal layer
`for twisting at least one normally incident visible wave
`length of light from about 80 to 100 as it passes there
`through when the liquid crystal layer is in Substantially the
`off-state thereby defining a twisted nematic display. The
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`BACKGROUND OF THE INVENTION
`The present invention relates generally to liquid crystal
`displays and more particularly to an improved liquid crystal
`display exhibiting enhanced optical viewing performance.
`Liquid crystal displays, which were first introduced in the
`1970s and have since been used in watches, clocks, pocket
`calculators, portable personal computers, navigational
`instruments and the like, are electronically Switched displayS
`that make use of changes in the reflective properties of liquid
`crystals present in an electric field. A typical liquid crystal
`display comprises a liquid crystal display panel, Said panel
`comprising a thin film of liquid crystals Sandwiched between
`a pair of transparent electrodes. The ruggedized liquid
`crystal display panel is typically positioned between a pair
`of glass plates, the glass plates being Sealed together around
`their respective edgeS. The glass plates may be assembled
`with Spacers between them to maintain a constant Separation
`distance. Two crossed axis polarizers are adhered to the
`respective inside Surfaces of the glass plates, one polarizer
`also being adhered to the front of the liquid crystal display
`panel and the other polarizer also being adhered to the rear
`of the liquid crystal display panel. When a Voltage is applied
`Selectively across the electrodes, the liquid crystal molecules
`between them are rearranged or Switched in polarization So
`that light is either reflected or absorbed in the region
`bounded by the electrodes to form characters or graphics.
`Many liquid crystal displays include a backlight for night or
`dark Viewing, and many liquid crystal displays include a
`layer of indium tin oxide or another Suitable material posi
`tioned between the front polarizer and the front glass plate
`for use as an electromagnetic interference Shield. Some
`liquid crystal displays intended for use in cold environments
`also include a layer of indium tin oxide or another Suitable
`material positioned between the rear polarizer and the rear
`glass plate and electrically connected to a power Source for
`use as a heating element.
`Some of the advantages of liquid crystal displays, as
`compared to other digital displays, are their comparatively
`low voltage and power requirements. Unfortunately,
`however, one of the principal disadvantages of liquid crystal
`displayS is that, due to their low contrast and a “washed-out”
`effect caused by back-reflected ambient light Seen by a
`Viewer, they cannot easily be read under high ambient light
`conditions, Such as when placed in direct Sunlight.
`One approach which has been taken to improve the
`Viewing performance of liquid crystal displays, particularly
`when viewed under high ambient light conditions, has been
`to apply an anti-reflection coating to the front of the display.
`Although Such an approach has provided Some improvement
`to the viewing characteristics of liquid crystal displays by
`reducing the amount of back-reflected light Seen by the
`Viewer, further improvement is greatly needed.
`A few patents in the field of liquid crystal display tech
`nology are described below.
`In U.S. Pat. No. 5,570,214, inventors Abileah et al., which
`issued Oct. 29, 1996, and which is incorporated herein by
`60
`reference, there is disclosed a liquid crystal display com
`prising a plurality of pixels, each of the pixels being com
`prised of a pair of driving electrodes and a twisted nematic
`liquid crystal material located therebetween. The liquid
`crystal material is of a thickness “d” and has an anistrophy
`AN such that the product of d'AN is about 400–550 nm, and
`the liquid crystal material is capable of twisting at least one
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`display also comprises a pair of negative retarderS Sand
`Wiching the liquid crystal layer therebetween and a pair of
`positive retarderS Sandwiching both the liquid crystal layer
`and the negative retarders therebetween, wherein the retar
`dation value of each of the negative retarderS is from about
`-60 to -200 nm and the retardation value of each of the
`positive retarders is from about 80 to 200 nm.
`SUMMARY OF THE INVENTION
`It is an object of the present invention to provide a novel
`liquid crystal display.
`It is another object of the present invention to provide a
`liquid crystal display that ameliorates at least Some of the
`problems discussed above in connection with existing liquid
`crystal displayS.
`It is yet another object of the present invention to provide
`a liquid crystal display as described above that includes a
`novel optical filtering arrangement.
`The present invention is based, in part, on the innovative
`discovery that the amount of back-reflected light Seen by a
`Viewer of a liquid crystal display can be Substantially
`reduced and, therefore, that the Viewing characteristics of a
`liquid crystal display can be Substantially improved by
`moving the front polarizer from its conventional location
`where it is adhered to the front Surface of the liquid crystal
`display panel and is positioned rearwardly relative to a first
`glass plate to a new location where it is in front of Said first
`glass plate and is adhered to the back Surface of another
`glass plate itself positioned in front of Said first glass plate.
`Therefore, according to one aspect of the invention, there
`is provided a liquid crystal display comprising (a) a first
`glass plate; (b) a second glass plate; (c) a liquid crystal
`display panel positioned between Said first and Second glass
`plates; (d) a rear polarizer positioned between said liquid
`crystal display panel and said Second glass plate; and (e) a
`front polarizer positioned in front of Said first glass plate,
`Said front polarizer being crossed relative to Said rear
`polarizer.
`In a preferred embodiment, the liquid crystal display
`comprises a first glass Substrate, a Second glass Substrate and
`an active matrix liquid crystal display panel. The display
`additionally comprises a rear polarizer, the front Surface of
`Said rear polarizer being adhered to the rear Surface of the
`active matrix liquid crystal display panel with an index
`matched, pressure Sensitive adhesive. The display further
`comprises an indium tin oxide thin film coating adapted to
`be used as a heating element, Said coating being applied to
`the front surface of the second glass Substrate. The front
`Surface of Said heating element is adhered to the rear Surface
`of the rear polarizer with a Silicone-based, index-matched,
`optical bonding material.
`In addition, Said ruggedized liquid crystal display may
`comprise an indium tin oxide thin film coating uSable as an
`electromagnetic interference (EMI) shield, said coating
`being applied to the rear Surface of the first glass Substrate.
`The rear surface of said EMI-coated glass substrate is
`adhered to the front surface of the active matrix liquid
`crystal display panel with the above-mentioned Silicone
`based, index-matched, optical bonding material.
`The display also comprises a front polarizer, Said front
`polarizer having a crossed axis relative to Said rear polarizer.
`The rear Surface of the front polarizer is adhered to the front
`Surface of the first glass Substrate by the above-mentioned
`Silicone-based, index-matched, optical bonding material.
`The display additionally comprises a third glass Substrate,
`the rear Surface of the third glass Substrate being bonded to
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`the front of the front polarizer by the above-mentioned
`index-matched, pressure Sensitive adhesive. The display
`further includes an anti-reflection (AR) thin film coating
`applied to the front Surface of the third glass Substrate.
`In order to minimize the reflection of ambient light by the
`display into the view of an observer, the various elements of
`the display preferably have respective indices of refraction
`that differ as minimally as possible. Nevertheless, as can
`readily be appreciated, this index-matching approach cannot
`completely eliminate the reflection of ambient light off the
`various elements of the display. In fact, Some elements, Such
`as the indium tin oxide electromagnetic interference Shield,
`are quite reflective. The placement of the front polarizer in
`front of the indium tin oxide electromagnetic interference
`Shield in accordance with the teachings of the present
`invention, instead of behind it, Substantially ameliorates the
`problem of reflection off Said electromagnetic interference
`Shield. This is because ambient light passing through Said
`front polarizer becomes polarized in a first direction. If Said
`polarized ambient light is then reflected off Said electromag
`netic interference Shield, its polarization State changes in
`Such a way that it cannot pass back through Said front
`polarizer into the view of the viewer.
`The terms “front,” “in front of,” “front surface” or the
`like, when used herein to describe an element of a liquid
`crystal display or to denote the relative positions of two or
`more elements of a liquid crystal display, refer directionally
`to the viewer side of the liquid crystal display. The terms
`"behind,” “in back of,” “rear Surface' or the like, when used
`herein to describe an element of a liquid crystal display or
`to denote the relative positions of two or more elements of
`a liquid crystal display, refer directionally to the Side of the
`liquid crystal display facing away from the viewer, typically
`the backlight Side of the display.
`Additional objects, features, aspects and advantages of the
`present invention will be set forth, in part, in the description
`which follows and, in part, will be obvious from the descrip
`tion or may be learned by practice of the invention. Certain
`embodiments of the invention will be described hereafter in
`Sufficient detail to enable those skilled in the art to practice
`the invention, and it is to be understood that other embodi
`ments may be utilized and that Structural or other changes
`may be made without departing from the Scope of the
`invention. The following detailed description is, therefore,
`not to be taken in a limiting Sense, and the Scope of the
`present invention is best defined by the appended claims.
`BRIEF DESCRIPTION OF THE DRAWINGS
`The accompanying drawing, which is hereby incorporated
`into and constitutes a part of this specification, illustrates a
`preferred embodiment of the invention and, together with
`the description, Serves to explain the principles of the
`invention. In the drawing wherein like reference numerals
`represent like parts:
`FIG. 1 is a schematic section view of one embodiment of
`a liquid crystal display constructed according to the teach
`ings of the present invention.
`DETAILED DESCRIPTION OF PREFERRED
`EMBODIMENTS
`AS noted above, the present invention is directed to the
`problem of poor viewing performance or “washout' in
`liquid crystal displays, Said problem occurring most notably
`under high ambient light conditions. More specifically, the
`problem is caused by the reflection of ambient light by the
`liquid crystal display back towards the viewer, thereby
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`obscuring the image generated by the liquid crystal display.
`Moreover, in those instances in which the liquid crystal
`display includes an electromagnetic interference Shield,
`often in the form of an indium tin oxide coating applied to
`the rear Surface of the front glass panel of the display, the
`problem of ambient light reflection into the view of an
`observer is made more acute.
`As will hereinafter be described, the present inventors
`have addressed the foregoing problem by, among other
`things, re-positioning the front polarizer of the liquid crystal
`display So that it is placed in front of the electromagnetic
`interference shield, instead of behind it. In this manner, as
`ambient light passes through the front polarizer, Said ambi
`ent light becomes polarized in a first direction. If Said
`polarized ambient light is then reflected off Said electromag
`netic interference Shield, its State of polarization changes.
`With its polarization state thus changed, the reflected ambi
`ent light cannot pass back through the front polarizer into the
`view of the observer.
`Referring now to FIG. 1, there is shown a schematic
`Section view of one embodiment of a liquid crystal display
`constructed according to the teachings of the present
`invention, Said liquid crystal display being represented gen
`erally by reference numeral 11.
`Liquid crystal display 11 comprises a first glass Substrate
`13, a Second glass Substrate 15 and a liquid crystal display
`(LCD) panel 17, LCD panel 17 being positioned between
`glass substrates 13 and 15. Glass substrates 13 and 15, which
`may be conventional in nature, typically have a thickness of
`about 0.04 inch and may be made of a borosilicate, a
`Sodalime or the like. Preferably, glass substrates 13 and 15
`have indices of refraction that substantially match that of
`LCD panel 17. LCD panel 17, which is preferably (but not
`necessarily) an active matrix liquid crystal display
`(AMLCD) panel, may be conventional in nature and
`includes liquid crystals (not shown) Sandwiched between a
`pair of transparent electrodes (not shown).
`Display 11 also comprises a rear polarizer 19, rear polar
`izer 19 preferably having an index of refraction that Sub
`stantially matches that of LCD panel 17. The front surface
`of rear polarizer 19 is preferably adhered to the rear surface
`of LCD panel 17 with a layer 21 of a conventional
`indexmatched, pressure Sensitive adhesive (layer 21 being
`about 0.001 inch in thickness). (Where rear polarizer 19 is
`a conventional non-compensated linear polarizer, layer 21
`may be applied to polarizer 19 by the polarizers
`manufacturer.) Rear polarizer 19 may be, for example, a
`conventional linear polarizer with an expanded viewing
`angle compensation film (for use in countering the birefrin
`gent effect of the liquid crystal material in panel 17) or a
`conventional non-compensated linear polarizer. Where rear
`polarizer 19 is a linear polarizer with an expanded viewing
`angle compensation film, the compensation film faces for
`wardly towards panel 17.
`In addition, display 11 preferably comprises a thin film
`coating 23 applied to the front Surface of Second glass
`substrate 15. Coating 23, whose index of refraction substan
`tially matches that of glass Substrate 15, is preferably made
`of indium tin oxide or another Suitable material So that, when
`coupled to a power Source, coating 23 Serves as a heating
`element to heat display 11 when it is used in cold ambient
`temperature conditions. The front Surface of coating 23 is
`preferably adhered to the rear surface of rear polarizer 19
`with a layer 25 of an index-matched, optical bonding mate
`rial. Layer 25, which may be made of, for example, a
`Silicone-based or epoxy-based, index-matched, optical
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`bonding material, advantageously eliminates any air gap
`between rear polarizer 19 and coating 23.
`Display 11 preferably further comprises an electromag
`netic interference (EMI) shield 27. EMI shield 27, which is
`preferably in the form of an indium tin oxide thin film
`coating applied to the rear Surface of first glass Substrate 13,
`Shields LCD panel 17 from incoming electromagnetic radia
`tion by absorbing said radiation. EMI shield 27 preferably
`has an index of refraction that Substantially matches that of
`LCD panel 17, and the rear surface of EMI shield 27 is
`preferably adhered to the front surface of LCD panel 17 with
`a layer 29 of the above-mentioned index-matched, optical
`bonding material.
`Display 11 also comprises a front polarizer 31, front
`polarizer 31 being similar to rear polarizer 19 but crossed
`relative thereto. Where front polarizer 31 (like rear polarizer
`19) includes a compensation film, the compensation film of
`front polarizer 31 faces forwardly away from LCD panel 17.
`Front polarizer 31 preferably has an index of refraction
`Substantially matching that of first glass Substrate 13, and the
`rear surface of front polarizer 31 is preferably adhered to the
`front surface of first glass substrate 13 by a layer 33 of the
`above-mentioned index-matched, optical bonding material.
`Display 11 additionally comprises a third glass Substrate
`35, which may be identical in composition to glass Sub
`strates 13 and 15. Third glass Substrate 35 preferably has
`index of refraction Substantially matching that of front
`polarizer 31, and the rear surface of third glass substrate 35
`is preferably bonded to the front of front polarizer 31 by a
`layer 37 of the above-mentioned index-matched, pressure
`Sensitive adhesive. The peripheries of first glass Substrate
`13, second glass substrate 15 and third glass substrate 35 are
`preferably externally sealed to contain those elements of
`display 11 sandwiched therebetween.
`Display 11 further includes a conventional anti-reflection
`thin film coating 39 applied to the front surface of third glass
`substrate 35. Coating 39, which is typically about 1-2
`microns thick, may be made of, for example, magnesium
`fluoride and/or quartz.
`Display 11 further includes a backlight 41, which may be
`conventional in nature, positioned behind Second glass Sub
`Strate 15.
`Display 11 may be used in the conventional manner;
`however, because of its construction, display 11 exhibits
`improved optical viewing performance.
`The embodiments of the present invention recited herein
`are intended to be merely exemplary and those skilled in the
`art will be able to make numerous variations and modifica
`tions to it without departing from the Spirit of the present
`invention. All Such variations and modifications are intended
`to be within the scope of the present invention as defined by
`the claims appended hereto.
`What is claimed is:
`1. A liquid crystal display comprising:
`(a) a first glass plate;
`(b) a Second glass plate;
`(c) a liquid crystal display panel positioned between said
`first and Second glass plates,
`(d) a rear polarizer positioned between said liquid crystal
`display panel and Said Second glass plate;
`(e) a front polarizer positioned in front of Said first glass
`plate, Said front polarizer being crossed relative to Said
`rear polarizer, and
`(f) an electromagnetic interference shield positioned
`between Said first glass plate and Said liquid crystal
`display panel.
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`2. The liquid crystal display as claimed in claim 1 wherein
`Said electromagnetic interference shield is an indium tin
`oxide thin film coating applied to the first glass plate.
`3. A liquid crystal display comprising:
`(a) a first glass Substrate;
`(b) a Second glass Substrate;
`(c) a liquid crystal display panel positioned between said
`first and Second glass Substrates,
`(d) a rear polarizer positioned between said liquid crystal
`display panel and Said Second glass Substrate;
`(e) a front polarizer positioned in front of Said first glass
`Substrate, Said front polarizer being crossed relative to
`Said rear polarizer;
`(f) an electromagnetic interference shield positioned
`between Said first glass Substrate and Said liquid crystal
`display panel; and
`(g) a third glass Substrate positioned in front of Said front
`polarizer.
`4. A liquid crystal display comprising:
`(a) a first glass Substrate;
`(b) a Second glass Substrate;
`(c) a liquid crystal display panel positioned between said
`first and Second glass Substrates,
`(d) a rear polarizer positioned between said liquid crystal
`display panel and Said Second glass Substrate;
`(e) a front polarizer positioned in front of Said first glass
`Substrate, Said front polarizer being crossed relative to
`Said rear polarizer;
`(f) an electromagnetic interference shield positioned
`between Said first glass Substrate and Said liquid crystal
`display panel, and
`(g) a third glass Substrate positioned in front of Said front
`polarizer;
`(h) wherein all of Said first glass Substrate, Said Second
`glass Substrate, Said third glass Substrate, Said front
`polarizer, Said rear polarizer and Said electromagnetic
`interference shield have indices of refraction that are
`Substantially matched.
`5. The liquid crystal display as claimed in claim 4 further
`comprising a heating element positioned between Said rear
`polarizer and Said Second glass Substrate and adapted to be
`connected to a power Source for use as a heating element,
`Said heating element having an index of refraction Substan
`tially matching that of Said rear polarizer and that of Said
`Second glass Subtrate.
`6. The liquid crystal display as claimed in claim 5 wherein
`Said heating element is a coating applied to Said Second glass
`Substrate and wherein Said electromagnetic Shield is a coat
`ing applied to Said first glass Substrate.
`7. The liquid crystal display as claimed in claim 6 wherein
`Said front polarizer is adhered to Said third glass Substrate
`with an index-matched pressure Sensitive adhesive and is
`bonded to Said first glass SubStrate with an index-matched
`optical bonding material, wherein Said rear polarizer is
`adhered to Said liquid crystal panel with an index-matched
`preSSure Sensitive adhesive and is bonded to Said heating
`element with an index-matched optical bonding material and
`wherein Said electromagnetic interference shield is bonded
`to Said liquid crystal display panel with an index-matched
`optical bonding material.
`8. The liquid crystal display as claimed in claim 7 further
`comprising an anti-reflection coating applied to the front of
`Said third glass Substrate.
`9. The liquid crystal display as claimed in claim 8 further
`comprising a backlight positioned behind Said Second glass
`Substrate.
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`15
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`25
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`35
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`40
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`45
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`50
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`55
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`65
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`US 6,181,394 B1
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`8
`10. The liquid crystal display as claimed in claim 9
`wherein Said liquid crystal display panel is an active matrix
`liquid crystal display panel.
`11. The liquid crystal display as claimed in claim 9
`wherein Said front and rear polarizers are non-compensated
`linear polarizers.
`12. A liquid crystal display comprising:
`(a) a first glass plate;
`(b) a Second glass plate;
`(c) a liquid crystal display panel positioned between said
`first and Second glass plates,
`(d) a rear polarizer positioned between said liquid crystal
`display panel and Said Second glass plate, Said rear
`polarizer being adhered directly to Said liquid crystal
`display panel with a first adhesive;
`(e) a front polarizer positioned in front of Said first glass
`plate and adhered directly to Said first glass plate with
`a Second adhesive, Said front polarizer being crossed
`relative to said rear polarizer; and (f) an electromag
`netic interference Shield positioned between Said first
`glass plate and Said liquid crystal display panel, Said
`electromagnetic interference Shield being adhered
`directly to Said liquid crystal display panel.
`13. The liquid crystal display as claimed in claim 12
`wherein Said electromagnetic interference shield is a coating
`applied to Said first glass plate.
`14. The liquid crystal display as claimed in claim 13
`further comprising a heating element positioned between
`Said rear polarizer and Said Second glass plate and adapted
`to be connected to a power Source for use as a heater, Said
`heating element being a coating applied to Said Second glass
`plate and adhered directly to Said rear polarizer.
`15. The liquid crystal display as claimed in claim 14
`further comprising a third glass plate, said third glass plate
`being positioned in front of and adhered directly to Said front
`polarizer.
`16. The liquid crystal display as claimed in claim 15
`further comprising an anti-reflection coating applied to the
`front of Said third glass plate.
`17. A liquid crystal display comprising:
`(a) a liquid crystal display panel;
`(b) a single rear glass plate positioned behind said liquid
`crystal display panel;
`(c) a first front glass plate, said first front glass plate being
`positioned in front of Said liquid crystal display panel;
`(d) a rear polarizer positioned between said liquid crystal
`display panel and Said Single rear glass plate;
`(e) a front polarizer positioned in front of said first front
`glass plate, Said front polarizer being crossed relative to
`Said rear polarizer, and
`(f) an electromagnetic interference shield positioned
`between Said first front glass plate and Said liquid
`crystal display panel.
`18. The liquid crystal display as claimed in claim 17
`further comprising a Second front glass plate, Said Second
`front glass plate being positioned in front of Said front
`polarizer.
`19. A liquid crystal display comprising:
`(a) a first glass plate;
`(b) a Second glass plate;
`(c) a liquid crystal display panel positioned between said
`first and Second glass plates,
`(d) a rear polarizer positioned between said liquid crystal
`display panel and Said Second glass plate;
`(e) a front polarizer positioned in front of Said first glass
`plate, Said fro