Liquid crystal cells – elements and systems – Particular structure – Having significant detail of cell structure only
Reexamination Certificate
2001-12-28
2003-07-22
Ngo, Julie (Department: 2871)
Liquid crystal cells, elements and systems
Particular structure
Having significant detail of cell structure only
C349S110000
Reexamination Certificate
active
06597420
ABSTRACT:
This application claims the benefit of the Korean Application No. P2000-086745 filed on Dec. 30, 2000, which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a display device, and more particularly, to a liquid crystal display (LCD) device and a method for manufacturing the same.
2. Discussion of the Related Art
With the advent of an information society of the 20th century, display devices obtaining low power consumption, high quality, miniaturization and portability have been required in various consumption patterns.
A TFT-LCD device, a flat panel display device including a plasma display panel (PDP) having a large size, can satisfy these requests, so that the TFT-LCD device has been attracted as a display device that can substitute for a related art CRT device.
Especially, the TFT-LCD device can obtain lightness in weight, high resolution, low power consumption, and portability. Furthermore, the TFT-LCD device does not generate electromagnetic waves having biological hazard, and can be used in the intelligent buildings of high technology all day.
However, the TFT-LCD device has problems such as high manufacturing cost, narrow viewing angle, low luminance and disadvantage for manufacturing large sized display device even though technology of the display device is considerably developed.
A related art LCD device will be described with reference to the accompanying drawings.
FIG. 1
is a plan view of the related art LCD device, and
FIG. 2
is a sectional view showing a structure of the related art LCD device taken along line I-I′ of FIG.
1
.
In general, an LCD device includes a lower substrate, an upper substrate, and a liquid crystal layer. A thin film transistor (TFT) array region is formed in the lower substrate, a black matrix film and a color filter film are formed on the upper substrate, and the liquid crystal layer is formed between the lower and upper substrates.
As shown in FIG.
1
and
FIG. 2
, a plurality of gate lines
110
are formed on the lower substrate
101
a
at a constant distance, and a plurality of data lines
103
are formed in perpendicular to the plurality of gate lines to define pixel regions of matrix type. Then, a plurality of TFTs are formed at crossing points of the plurality of gate and data lines
110
and
103
in each pixel region, and a plurality of pixel electrodes
105
are formed in each pixel region.
At this time, the unit TFT includes a gate electrode and source/drain electrodes. The gate electrode of the TFT (not shown in
FIG. 2
) projects from the gate line
110
on the lower substrate
101
a
. Then, a gate insulating film
102
is formed on an entire surface of the lower substrate including the gate electrode and the gate line, and the data line
103
and the source/drain electrodes (not shown in
FIG. 2
) are formed on the gate insulating film
102
. A passivation film
104
of a silicon nitride film is formed on the entire surface of the lower substrate including the data line
103
and the source/drain electrodes. At this time, the drain electrode is connected to the pixel electrode
105
through a contact hole formed in the passivation film
104
on the drain electrode.
A plurality of black matrix films
106
are patterned on the upper substrate
101
b
at a constant distance to prevent light from being incident on the plurality of data lines
103
, the plurality of gate lines
110
and the TFTs on the lower substrate
101
a
. Then, R/G/B color filter films
107
are formed between the black matrix films
106
for displaying colors, and then an over coat film
108
is formed on the color filter films
107
to protect and planarize the color filter films
107
. Then, a plurality of common electrodes
109
of ITO are formed on the over coat film
108
.
The lower and upper substrates
101
a
and
101
b
are attached to each other with a constant distance, and liquid crystal is injected between the lower and upper substrates.
However, the related art LCD device and the method for manufacturing the same have the following problems.
The plurality of black matrix films are formed on portions of the upper substrate corresponding to the TFTs and the gate/data lines, and then the color filter films are formed on the black matrix films. At this time, to obtain low resistance on a transparent conductive film, contact areas between the transparent conductive film and the black matrix film are reduced. Accordingly, uniformity of common voltage on the upper substrate can be degraded.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to an LCD device 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 an LCD device and a method for manufacturing the same that can improve uniformity of common voltage by increasing contact areas between a black matrix film and a transparent conductive film.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may 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 these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, an LCD device includes first and second substrates facing to each other, a plurality of color filter films formed in each pixel region on the first substrate, a plurality of gate and data lines formed on the color filter films to cross one another to define the pixel regions, a plurality of TFTs formed at crossing points of the plurality of gate and data lines, a plurality of pixel electrodes formed in the pixel regions on the first substrate, a plurality of island shaped first black matrix films formed on portions of the second substrate corresponding to the TFTs, and a plurality of common electrodes formed on an entire surface of the second substrate including the first black matrix films.
Preferably, a plurality of second black matrix films are formed between portions of the second substrate corresponding to the plurality of gate/data lines and the plurality of common electrodes.
Preferably, the plurality of second black matrix films are connected to the plurality of first black matrix films.
Preferably, the plurality of second black matrix films are narrower than the gate lines or the data lines.
Preferably, the pixel electrodes are overlapped with the gate lines or the data lines.
Preferably, a plurality of third black matrix films are formed between the color filter films below the TFTs and the first substrate, and a plurality of fourth black matrix films are formed between the color filter films below the gate/data lines and the first substrate.
Preferably, the plurality of third black matrix films prevent light of a backlight from being incident on active layers of the TFTs.
Preferably, the plurality of fourth black matrix films are wider than the gate lines or the data lines.
Preferably, the plurality of pixel electrodes are overlapped with the plurality of fourth black matrix films.
Preferably, a liquid crystal layer is formed between the first and second substrates.
In an LCD device according to the second embodiment of the present invention, the LCD device includes first and second substrate facing to each other, a plurality of color filter films in each pixel region on the first substrate, a plurality of gate and data lines formed on the color filter films to cross one another to define the pixel regions, a plurality of TFTs at crossing points of the plurality of gate and data lines, a plurality of pixel electrodes formed in each pixel region of the first substrate, a plurality of island shaped first black matrix films on portions o
Chang Youn Gyoung
Kim Woong Kwon
LG.Philips LCD Co. , Ltd.
Morgan & Lewis & Bockius, LLP
Ngo Julie
LandOfFree
Liquid crystal display device having color film on a first... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Liquid crystal display device having color film on a first..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Liquid crystal display device having color film on a first... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3107584