Liquid crystal cells – elements and systems – Particular structure – Having significant detail of cell structure only
Reexamination Certificate
2002-07-11
2003-12-16
Chowdhury, Tarifur R. (Department: 2871)
Liquid crystal cells, elements and systems
Particular structure
Having significant detail of cell structure only
C349S123000, C349S138000, C349S143000, C349S117000
Reexamination Certificate
active
06665035
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a liquid crystal display device (LCD), and more particularly to a multi-domain liquid crystal display device capable distorting electric field and shielding light.
2. Description of the Related Art
Recently, a LCD has been proposed where the liquid crystal is not aligned and the liquid crystal is driven by side electrodes insulated from pixel electrodes.
FIG. 1
is a sectional view of pixel unit of the conventional LCDs.
Regarding conventional LCDs, a plurality of gate bus lines arranged in a first direction on a first substrate and a plurality of data bus lines arranged in a second direction on the first substrate divide the first substrate into a plurality of pixel regions.
A thin film transistor (TFT) applies image signal delivered from the data bus line to a pixel electrode
13
on a passivation layer
4
. The TFT is formed on each pixel region and comprises a gate electrode, a gate insulator, a semiconductor layer, a source electrode, and a drain electrode, etc.
Side electrode
15
is formed surrounding the pixel electrode
13
on the gate insulator, thereon passivation layer
4
is formed over the whole first substrate, and a part of pixel electrode
13
overlaps side electrode
15
.
Alternatively, pixel electrode
13
is formed on the gate insulator and passivation layer
4
is formed over the whole first substrate. Afterward, side electrode
15
is formed as overlapping a part of pixel electrode
13
. Moreover, it is possible to pattern the pixel electrode
13
by etching and dividing the pixel region.
On a second substrate, a common electrode
17
is formed and together with pixel electrode.
13
applies electric field to a liquid crystal layer. Side electrode
15
and open area (slit)
19
distort the electric field applied to the liquid crystal layer. Then, liquid crystal molecules are variously driven in a unit pixel. Thus, when voltage is applied to the LCD, dielectric energy due to the distorted electric field arranges the liquid crystal directors in a needed position.
In the LCDs, however, open area
19
in common electrode
17
or pixel electrode
13
is necessary, and the liquid crystal molecules could be driven stably when the open area is wider. If the electrodes do not have a slit or the width of the slit is narrow, the electric field distortion needed to divide the pixel region becomes weak. Then, when voltage over a threshold voltage, V
th
, is applied, the time needed to stabilize the liquid crystal directors increases.
In particular, the response time can be over 100 msec. At this time, disclination occurs from the area where the liquid crystal directors are parallel with a transmittance axis of the polarizer, which results in a decrease in brightness. Further, according to the surface state of LCDs, the liquid crystal texture has an irregular structure.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a LCD that substantially obviates one or more problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a LCD having a wide viewing angle from a multi-domain effect.
Another object of the present invention is to provide a LCD having high brightness by stable arrangement of liquid crystal molecules.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve the objects and in accordance with the purpose of the invention, as embodied and broadly described herein, a multi-domain liquid crystal display device comprises first and second substrates facing each other; a liquid crystal layer between the first and second substrates; a plurality of gate bus lines arranged in a first direction on the first substrate and a plurality of data bus lines arranged in a second direction on the first substrate to define a pixel region; a thin film transistor positioned at a crossing area of the data bus line and the gate bus line and comprising a gate electrode, a semiconductor layer, and source/drain electrodes; a pixel electrode in the pixel region; a field-affecting electrode on the second substrate; a color filter layer on the field affecting electrode; and a common electrode on the color filter layer.
In another aspect, the multi-domain liquid crystal display of the present invention comprises first and second substrates facing each other; a liquid crystal layer between the first and second substrates; a plurality of gate bus lines arranged in a first direction on the first substrate and a plurality of data bus lines arranged in a second direction on the first substrate to define a pixel region; a thin film transistor positioned at a crossing area of the data bus line and the gate bus line and comprising a gate electrode, a semiconductor layer, and source/drain electrodes; a pixel electrode in the pixel region; a subsidiary electrode on a the second substrate; a color filter layer on the subsidiary electrode; a common electrode on the color filter layer; and an alignment layer on at least one of the first and second substrates.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
REFERENCES:
patent: 3914022 (1975-10-01), Kashnow
patent: 4581608 (1986-04-01), Aftergut et al.
patent: 4701028 (1987-10-01), Clerc et al.
patent: 4728175 (1988-03-01), Baron
patent: 4786147 (1988-11-01), Clerc et al.
patent: 4889412 (1989-12-01), Clerc et al.
patent: 4937566 (1990-06-01), Clerc
patent: 4978203 (1990-12-01), Yamazaki et al.
patent: 5039185 (1991-08-01), Uchida et al.
patent: 5093741 (1992-03-01), Shohara et al.
patent: 5182664 (1993-01-01), Clerc
patent: 5229873 (1993-07-01), Hirose et al.
patent: 5249070 (1993-09-01), Takano
patent: 5309264 (1994-05-01), Lien et al.
patent: 5339181 (1994-08-01), Kim et al.
patent: 5477358 (1995-12-01), Rosenblatt et al.
patent: 5517341 (1996-05-01), Kim et al.
patent: 5517342 (1996-05-01), Kim et al.
patent: 5574582 (1996-11-01), Takeda et al.
patent: 5602662 (1997-02-01), Rosenblatt et al.
patent: 5608556 (1997-03-01), Koma
patent: 5621558 (1997-04-01), Shimada et al.
patent: 5623354 (1997-04-01), Lien et al.
patent: 5666179 (1997-09-01), Koma
patent: 5668650 (1997-09-01), Mori et al.
patent: 5673092 (1997-09-01), Horie et al.
patent: 5686977 (1997-11-01), Kim et al.
patent: 5737051 (1998-04-01), Kondo et al.
patent: 5767926 (1998-06-01), Kim et al.
patent: 5777701 (1998-07-01), Zhang
patent: 5777711 (1998-07-01), Sugiyama
patent: 0 752 611 (1997-01-01), None
patent: 0 814 142 (1997-12-01), None
patent: 0 854 377 (1998-07-01), None
patent: 0 884 626 (1998-12-01), None
patent: 2 296 810 (1996-07-01), None
patent: 2 321 718 (1998-08-01), None
patent: 2 337 843 (1999-12-01), None
patent: 2-294622 (1990-12-01), None
patent: 3-261914 (1991-11-01), None
patent: 4-67127 (1992-03-01), None
patent: 4-261522 (1992-09-01), None
patent: 5-2161 (1993-01-01), None
patent: 05-297412 (1993-11-01), None
patent: 6-194656 (1994-07-01), None
patent: 6-194657 (1994-07-01), None
patent: 6-258649 (1994-09-01), None
patent: 6-273798 (1994-09-01), None
patent: 6-281959 (1994-10-01), None
patent: 6-347824 (1994-12-01), None
patent: 7-13164 (1995-01-01), None
patent: 7-13166 (1995-01-01), None
patent: 7-28063 (1995-01-01), None
patent: 7-36044 (1995-02-01), None
patent: 7-43698 (1995-02-01), None
patent: 7-43719 (1995-02-01), None
patent: 7-64089 (1995-03-01), None
patent: 7-181493 (1995-07-01), None
patent: 7-199190 (1995-08-01), None
patent: 7-311383 (1995-11-01), None
patent: 8-22023 (1996-01-01), None
patent: 8-76125 (1996-03-01), None
patent: 8-101399 (1996-04-01), None
patent: 8-146
Chowdhury Tarifur R.
LG.Philips LCD Co. , Ltd.
McKenna Long & Aldridge
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