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US4828364A Expired / Lapsed US ⏱️ 0.0 years remaining

Liquid crystal display device with light shield of specific transmittance

Assignee: AGC Inc
•
Filing: 1987-12-09
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Granted: 1989-05-09
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Expires: 2007-12-09
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Abstract

Abstract A liquid crystal display device of negative display type, which comprises a liquid crystal cell comprising a nematic liquid crystal layer sandwiched between substrates provided with electrodes and a light shielding layer covering other than the area corresponding to a display pattern and adapted to apply a voltage sufficient to energize the nematic liquid crystal to the electrodes at a display pattern area other than a desired display pattern, and a pair of polarizing films provided on both sides of the liquid crystal cell with their polarization axes arranged to permit light from a no voltage-applied portion to pass therethrough, wherein the light shielding layer has a light transmittance of not higher than 1.0% and higher than the minimum light transmittance of the display pattern area during the application of the voltage.

Inventors

  • 👤 Yuichi Saito
  • 👤 Fumio Kadoo

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 06:43
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/133345; G02F1/1335; G02F1/133509; G02F1/137; G02F1/139; G02F1/1396; G02F1/133512

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 139 words
A liquid crystal display device of negative display type, which comprises a liquid crystal cell comprising: a nematic liquid crystal layer sandwiched between substrates provided with electrodes; a light shielding layer covering other than the area corresponding to a display pattern; an orientation layer placed on said light shielding layer; means for applying a voltage sufficient to energize the nematic liquid crystal to the electrodes at a display pattern area other than a desired display pattern; and a pair of polarizing films provided on both sides of the liquid crystal cell with their polarization axes arranged to permit light from a no voltage-applied portion to pass therethrough, wherein the light shielding layer has a light transmittance of not higher than 1.0% and higher than the minimum light transmittance of the display pattern area during the application of the voltage.
Claim 2
Dependent Claim 139 words
A liquid crystal display device of negative display type, which comprises a liquid crystal cell comprising: a nematic liquid crystal layer sandwiched between substrates provided with electrodes; a light shielding layer covering other than the area corresponding to a display pattern; an orientation layer placed on said light shielding layer; means for applying a voltage sufficient to energize the nematic liquid crystal to the electrodes at a display pattern area other than a desired display pattern; and a pair of polarizing films provided on both sides of the liquid crystal cell with their polarization axes arranged to permit light from a no voltage-applied portion to pass therethrough, wherein the light shielding layer has a light transmittance of not higher than 1.0% and higher than the minimum light transmittance of the display pattern area during the application of the voltage.
Claim 3
Dependent Claim 41 words
The liquid crystal display device according to claim 1, wherein the light transmittance of the light shielding layer is from 2 to 20 times higher than the minimum light transmittance of the display pattern area during the application of the voltage.
Claim 4
Dependent Claim 23 words
The liquid crystal display device according to claim 1, wherein the light transmittance of the light shielding layer is form 0.1 to 1.0%.
Claim 5
Dependent Claim 42 words
The liquid crystal display device according to claim 2, wherein the nematic liquid crystal is twisted at an angle of about 90° and the pair of the polarizing films are disposed so that their polarization axes are substantially perpendicular to each other.
Claim 6
Dependent Claim 23 words
The liquid crystal display device according to claim 2, wherein the light shielding layer is formed on the inner surface of a substrate.
Claim 7
Dependent Claim 19 words
The liquid crystal display device according to claim 5, wherein the light shielding layer is formed on an electrode.
Claim 8
Dependent Claim 20 words
The liquid crystal display device according to claim 6, wherein the light shielding layer is formed on a common electrode.
Claim 9
Dependent Claim 24 words
The liquid crystal display device according to claim 5, wherein the light shielding layer is a layer formed by printing a light shielding ink.
Claim 10
Dependent Claim 20 words
The liquid crystal display device according to claim 8, wherein the light shielding layer is formed on a common electrode.
Claim 11
Dependent Claim 49 words
The liquid crystal display device according to claim 2, wherein the light transmittance of the light shielding layer is adjusted to substantially the same level as the contrast ratio at which substantially constant contrast is obtainable within a wide range of viewing angle of the liquid crystal display device.
Claim 12
Dependent Claim 21 words
The liquid crystal display device according to claim 1, wherein an illuminating means is provided behind the rear side polarizing film.
Claim 13
Dependent Claim 24 words
The liquid crystal display device according to claim 1, wherein a liquid crystal containing a dichroic dye is used as the nematic liquid crystal.
Claim 14
Dependent Claim 149 words
A liquid crystal display device, which comprises a liquid crystal cell comprising: a nematic liquid crystal layer sandwich between substrates provided with electrodes; a light shielding layer formed on an inner surface of at least one of the substrates to cover other than the area corresponding to a display pattern; an orientation layer placed on said light shielding layer; means for applying a voltage sufficient to energize the nematic liquid crystal to the electrodes at a display pattern area other than a desired display pattern; and a pair of polarizing films provided on both sides of the liquid crystal cell with therein polarization axes being substantially perpendicular to each other, wherein the light shielding layer has a light transmittance of not higher than 1.0% and from 2 to times higher than the minimum light transmittance of voltage, and an illuminating means is provided behind the rear side polarizing film.
Claim 15
Dependent Claim 149 words
A liquid crystal display device, which comprises a liquid crystal cell comprising: a nematic liquid crystal layer sandwich between substrates provided with electrodes; a light shielding layer formed on an inner surface of at least one of the substrates to cover other than the area corresponding to a display pattern; an orientation layer placed on said light shielding layer; means for applying a voltage sufficient to energize the nematic liquid crystal to the electrodes at a display pattern area other than a desired display pattern; and a pair of polarizing films provided on both sides of the liquid crystal cell with therein polarization axes being substantially perpendicular to each other, wherein the light shielding layer has a light transmittance of not higher than 1.0% and from 2 to times higher than the minimum light transmittance of voltage, and an illuminating means is provided behind the rear side polarizing film.
Claim 16
Dependent Claim 35 words
The liquid crystal display device according to claim 13, wherein a color filter layer :s provided on the inner surface of at least one of the substrates at the area corresponding to the display pattern.

References Cited (Backward Citations)

US4591240A Cited
US4601546A Cited
US4506956A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-05-08 1992-11-07 1993-05-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-05-08 1996-11-07 1997-05-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-05-08 2000-11-07 2001-05-09 $7700.00 Window Closed / Lapsed

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