Reflection type color liquid crystal display apparatus
First Claim
Patent Images
1. A reflection type liquid crystal display apparatus comprising:
- a polarizing plate,a birefringent plate having a twist angle,a liquid crystal layer of a nematic liquid crystal having positive dielectric anisotropy and including a chiral material, which is interposed between two substrates disposed to each other, each provided with an electrode, anda reflection layer arranged in successive order;
whereinsaid liquid crystal layer hasa twist angle θ
1 from the first orientation direction at its first plane of said liquid crystal layer to the second orientation direction at its second plane of said liquid crystal layer;
said birefringent plate has a twist angle θ
2 from a first slow axis of optical anisotropic axes in a plane at the side next to the polarizing plate to a second slow axis of optical anisotropic axes in opposite plane in a direction from the first slow axis to the second slow axis, andthe product of Δ
n1 ·
d1 of the refractive index anisotropy Δ
n1 of the liquid crystal in the liquid crystal layer and the thickness d1 of the liquid crystal layer is 0.30 to 2.00 μ
m;
the product of Δ
n2 ·
d2 of the refractive index anisotropy Δ
n2 of the birefringent plate and the thickness d2 of the birefringent plate is 0.30 to 2.00 μ
m;
an angle θ
3 is formed from said first orientation direction of the liquid crystal layer to the second slow axis of said birefringent plate;
an angle θ
4 is formed from said first slow axis of said birefringent plate to an absorbing axis of said polarizing plate;
the angles θ
1, θ
2, θ
3 and θ
4 in a clockwise (+) or in counterclockwise (-) direction have the following first conditions;
{θ
1 is -160°
to -300°
,θ
2 is +160°
to +300°
,θ
3 is (+90°
+ -10°
to +40°
!) andθ
4 is (+45°
+ -30°
to +25°
! or +135°
+ -30°
to +25°
!)};
or the following second conditions;
{θ
1 is +160°
to +300°
,θ
2 is -160°
to -300°
,θ
3 is (-90°
+ +10°
to -40°
!) andθ
4 is (-45°
+ +30°
to -25°
! or -135°
+ +30°
to -25°
!)};
and voltage values of at least 3 values are selected to be applied to said liquid crystal layer.
3 Assignments
0 Petitions
Accused Products
Abstract
A reflection type color liquid crystal display apparatus comprising a polarizing plate 1 having an absorbing axis 18, a birefringent plate 3, a liquid crystal layer 6 and a reflection layer 8 wherein the absorbing axis 18, a first orientation 14, a second orientation 15, a first optical anisotropic axis 16 and a second anisotropic axis 17 are set so as to form predetermined crossing angles θ1, θ2, θ3, θ4, and selected voltage values of at least three values are applied to the liquid crystal layer 6 from a multiplex driving circuit 10.
Without using a color filter, a very bright chromatic color (white or black) is displayed at the time of an OFF waveform even in multiplex driving, and development of colors of very bright red, blue and green can be obtained with a selection voltage or an intermediate voltage between the selection voltage and a non-selection voltage.
-
Citations
15 Claims
-
1. A reflection type liquid crystal display apparatus comprising:
-
a polarizing plate, a birefringent plate having a twist angle, a liquid crystal layer of a nematic liquid crystal having positive dielectric anisotropy and including a chiral material, which is interposed between two substrates disposed to each other, each provided with an electrode, and a reflection layer arranged in successive order;
whereinsaid liquid crystal layer has a twist angle θ
1 from the first orientation direction at its first plane of said liquid crystal layer to the second orientation direction at its second plane of said liquid crystal layer;said birefringent plate has a twist angle θ
2 from a first slow axis of optical anisotropic axes in a plane at the side next to the polarizing plate to a second slow axis of optical anisotropic axes in opposite plane in a direction from the first slow axis to the second slow axis, andthe product of Δ
n1 ·
d1 of the refractive index anisotropy Δ
n1 of the liquid crystal in the liquid crystal layer and the thickness d1 of the liquid crystal layer is 0.30 to 2.00 μ
m;the product of Δ
n2 ·
d2 of the refractive index anisotropy Δ
n2 of the birefringent plate and the thickness d2 of the birefringent plate is 0.30 to 2.00 μ
m;an angle θ
3 is formed from said first orientation direction of the liquid crystal layer to the second slow axis of said birefringent plate;an angle θ
4 is formed from said first slow axis of said birefringent plate to an absorbing axis of said polarizing plate;the angles θ
1, θ
2, θ
3 and θ
4 in a clockwise (+) or in counterclockwise (-) direction have the following first conditions;{θ
1 is -160°
to -300°
,θ
2 is +160°
to +300°
,θ
3 is (+90°
+ -10°
to +40°
!) andθ
4 is (+45°
+ -30°
to +25°
! or +135°
+ -30°
to +25°
!)};
or the following second conditions;{θ
1 is +160°
to +300°
,θ
2 is -160°
to -300°
,θ
3 is (-90°
+ +10°
to -40°
!) andθ
4 is (-45°
+ +30°
to -25°
! or -135°
+ +30°
to -25°
!)};and voltage values of at least 3 values are selected to be applied to said liquid crystal layer. - View Dependent Claims (2, 4, 5, 7, 8, 10, 11, 12, 13, 14)
- 14. The reflection type color liquid crystal apparatus according to claim 1, wherein
a relationship (3) and (4) is satisfied - space="preserve" listing-type="equation">(10°
).sup.2 ≦
(|θ
.sub.5 |-90°
).sup.2 +(|θ
.sub.6 |-45°
).sup.2 (
3)
space="preserve" listing-type="equation">(10°
).sup.2 ≦
(|θ
.sub.5 |-90°
).sup.2 +(|θ
.sub.6 |-135°
).sup.2 (
4). - space="preserve" listing-type="equation">(10°
-
-
3. 8=≦
- Δ
n1 ·
d1 ≦
1.5 andΔ
n1 ·
d1 -0.15≦
Δ
n2 ·
d2 ≦
Δ
n1 ·
d1 +0.15.
- Δ
-
6. 80≦
- Δ
n2 ·
d2 ≦
0.90.
- Δ
-
9. 70≦
- Δ
n2 ·
d2 ≦
0.90.
- Δ
-
15. A reflection type liquid crystal display apparatus comprising:
-
a polarizing plate, a birefringent plate having not a twist angle, a liquid crystal layer of a nematic liquid crystal having positive dielectric anisotropy and including a chiral material, which is interposed between two substrates disposed to each other, each provided with an electrode, and a reflection layer arranged in successive order;
whereinsaid liquid crystal layer has a twist angle θ
1 from the first orientation direction at its first plane of said liquid crystal layer to the second orientation direction at its second plane of said liquid crystal layer; andthe product of Δ
n1 ·
d1 of the refractive index anisotropy Δ
n1 of the liquid crystal in the liquid crystal layer and the thickness d1 of the liquid crystal layer is 0.30 to 2.00 μ
m;the product of Δ
n2 ·
d2 of the refractive index anisotropy Δ
n2 of the birefringent plate and the thickness d2 of the birefringent plate is 0.30 to 2.00 μ
m;an angle θ
5 formed from said first orientation direction of the liquid crystal layer to a slow axis of said birefringent plate;an angle θ
6 formed from said first orientation direction of the liquid crystal layer to an absorbing axis of said polarizing plate;the angles θ
1, θ
5 and θ
6 in a clockwise (+) or in counterclockwise (-) direction have such a relation that(θ
1 is -160°
to -300°
), (θ
5 is +70°
to +120°
) and (θ
6 is +25°
to +80°
or +115°
to +170°
)!;
or(θ
1 is +160°
to +300°
, (θ
5 is -70°
to -120°
) and (θ
6 is -25°
to -80°
or -115°
to -170°
)!; andvoltage values of at least 3 values are selected to be applied to said liquid crystal layer.
-
Specification
-
- Resources
Litigation Campaign Assessment
Thank you for your request. You will receive a custom alert email when the Litigation Campaign Assessment is available.
×
-
Current AssigneeOptrex Corporation (Kyocera Corporation)
-
Original AssigneeAsahi Glass Company, Limited (AGC, Inc.)
-
InventorsSuzuki, Toshihiko, Shidoji, Eiji, Mori, Haruki, Ozeki, Masao
-
Primary Examiner(s)NGUYEN, TIEP HUU
-
Application NumberUS08/776,592Time in Patent Office950 DaysField of Search349/76, 349/102, 349/121US Class Current349/121CPC Class CodesG02F 1/133531 characterised by the arrang...G02F 1/133553 Reflecting elements associa...G02F 1/133636 with twisted orientation, e...G02F 1/1397 the twist being substantial...G02F 2203/02 reflectiveG02F 2203/34 Colour display without the ...
