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US5570210A Expired / Lapsed US ⏱️ 0.0 years remaining

Liquid crystal display device with directional backlight and image production capability in the light scattering mode

Assignee: Sharp Corp
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Filing: 1994-01-31
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Granted: 1996-10-29
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Expires: 2014-01-31
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Abstract

Abstract A liquid crystal device including a liquid crystal layer comprising a liquid crystal of a dispersed type in which liquid crystal molecules are randomly distributed so that an incident light impinging against the liquid crystal molecules scatters to produce a white display spot. A polarizer and an analyzer are arranged on either side of the first and second transparent plates. A directional backlight is arranged on the outside of the polarizer for supplying light having a directivity in the direction perpendicular to the first and second transparent plates toward the polarizer.

Inventors

  • 👤 Hidefumi Yoshida
  • 👤 Kazutaka Hanaoka
  • 👤 Kimiaki Nakamura
  • 👤 Hideaki Tsuda
  • 👤 Fumiaki Yamada

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 14:04
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/1334; G02F1/133528; G02F1/133536; G02F1/133543; G02F1/13362; G02F1/137; G02F1/13756

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 254 words
A direct viewing type liquid crystal display device, comprising: a first transparent plate having inside and outside parallel main surfaces and a first transparent electrode formed on the inside main surface thereof; a second transparent plate having inside and outside parallel main surfaces and a second transparent electrode formed on the inside main surface thereof, the second transparent plate being positioned in spaced, parallel relationship to the first transparent plate with a gap between the respective inside main surfaces thereof; a liquid crystal layer having, selectively, a light scattering mode and a light transmitting mode and being disposed in the gap between the first and second transparent plates; a polarizer arranged on the outside main surface of the first transparent plate; an analyzer arranged on the outside main surface of the second transparent plate; and a directional backlight unit supplying a backlight to the direct viewing type liquid crystal display device, the backlight having a directivity substantially in a normal direction relatively to the respective main surfaces of the first and second transparent plates and a large proportion of the backlight, supplied from the backlight unit to the polarizer, having a directivity within an angular range of up to an angle of 10 degrees relative to the normal direction, the backlight being transmitted through the liquid crystal device in the light scattering mode of the liquid crystal layer for image production and being blocked by the analyzer after transmission through the liquid crystal layer in the light transmitting mode of the liquid crystal layer.
Claim 2
Dependent Claim 254 words
A direct viewing type liquid crystal display device, comprising: a first transparent plate having inside and outside parallel main surfaces and a first transparent electrode formed on the inside main surface thereof; a second transparent plate having inside and outside parallel main surfaces and a second transparent electrode formed on the inside main surface thereof, the second transparent plate being positioned in spaced, parallel relationship to the first transparent plate with a gap between the respective inside main surfaces thereof; a liquid crystal layer having, selectively, a light scattering mode and a light transmitting mode and being disposed in the gap between the first and second transparent plates; a polarizer arranged on the outside main surface of the first transparent plate; an analyzer arranged on the outside main surface of the second transparent plate; and a directional backlight unit supplying a backlight to the direct viewing type liquid crystal display device, the backlight having a directivity substantially in a normal direction relatively to the respective main surfaces of the first and second transparent plates and a large proportion of the backlight, supplied from the backlight unit to the polarizer, having a directivity within an angular range of up to an angle of 10 degrees relative to the normal direction, the backlight being transmitted through the liquid crystal device in the light scattering mode of the liquid crystal layer for image production and being blocked by the analyzer after transmission through the liquid crystal layer in the light transmitting mode of the liquid crystal layer.
Claim 3
Dependent Claim 60 words
A direct viewing type liquid crystal display device according to claim 1, wherein the backlight unit comprises: a lamp which emits divergent light beams; and a lens which converts the divergent light beams emitted by the lamp into generally parallel light beams extending substantially in the normal direction and within the angular range relative thereto, as supplied to the polarizer.
Claim 4
Dependent Claim 23 words
A direct viewing type liquid crystal display device according to claim 2, wherein the backlight unit further comprises means for inducing polarized light.
Claim 5
Dependent Claim 81 words
A direct viewing type liquid crystal display device according to claim 1, wherein the backlight unit further comprises: a lamp which emits divergent light beams; a lens which bends the divergent light beams emitted by the lamp into generally parallel light beams; a reflector arranged on a side of the lamp remote from the lens; and means, arranged between the lens and the polarizer, for receiving the generally parallel light beams and emitting the received light beams as polarized light beams.
Claim 6
Dependent Claim 38 words
A direct viewing type liquid crystal display device according to claim 1, wherein the liquid crystal layer includes randomly distributed liquid crystal molecules, incident light from the backlight unit impinging on the liquid crystal molecules being scattered thereby.
Claim 7
Dependent Claim 114 words
A direct viewing type liquid crystal display device according to claim 5, wherein the liquid crystal layer comprises a dispersed-type liquid crystal material in which liquid crystal molecules are randomly distributed so that incident light, impinging on the liquid crystal molecules, is scattered thereby in the absence of a voltage being applied to the liquid crystal layer and the liquid crystal molecules uniformly rise relative to the first and second transparent plates, when a voltage is applied to the liquid crystal, so that the incident light from the directional backlight unit and having a directivity substantially in the normal direction passes through the liquid crystal layer without being scattered by the liquid crystal molecules.
Claim 8
Dependent Claim 26 words
A direct viewing type liquid crystal display device according to claim 6, wherein the liquid crystal layer comprises liquid crystal capsules dispersed in a transparent material.
Claim 9
Dependent Claim 53 words
A direct viewing type liquid crystal display device according to claim 5, wherein the liquid crystal layer comprises: a first liquid crystal material in the gap between the first and second transparent plates; and liquid crystal capsules dispersed in the first liquid crystal material, each capsule including therein a second liquid crystal material.
Claim 10
Dependent Claim 25 words
A direct viewing type liquid crystal display device according to claim 5, wherein the liquid crystal layer comprises a polymer network type liquid crystal material.
Claim 11
Dependent Claim 23 words
A direct viewing type liquid crystal display device according to claim 5, wherein the liquid crystal layer comprises a macromolecular liquid crystal material.
Claim 12
Dependent Claim 122 words
A direct viewing type liquid crystal display device according to claim 1, wherein the liquid crystal layer has a scattering value greater than 5, the scattering value being defined by a reciprocal (L/T) of a ratio of an intensity of light (T) transmitting through the liquid crystal layer, measured by arranging the liquid crystal layer between a source of the laser beam and a light detector arranged so as to receive divergent light beams from the liquid crystal panel within the angular range of approximately 6 degrees, to an intensity of light (L) of the source of the laser beam, measured in the same arrangement of the source of the laser beam and the light detector but without any liquid crystal therebetween.
Claim 13
Dependent Claim 69 words
A direct viewing type liquid crystal display device according to claim 1, wherein the polarizer and the analyzer have respective transmitting axes which are perpendicular to each other, the backlight being transmitted through the liquid crystal display device in the light scattering mode of the liquid crystal layer and being blocked from transmission through the liquid crystal display device in the light non-scattering mode of the liquid crystal layer.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-10-29 2000-04-29 2000-10-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-10-29 2004-04-29 2004-10-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-10-29 2008-04-29 2008-10-29 $7700.00 Window Closed / Lapsed

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