U.S. patent application number 10/985910 was filed with the patent office on 2005-07-28 for liquid crystal display device having stripe-shaped color filters.
Invention is credited to Chung, In-Jae, Song, In-Duk.
Application Number | 20050162358 10/985910 |
Document ID | / |
Family ID | 19647585 |
Filed Date | 2005-07-28 |
United States Patent
Application |
20050162358 |
Kind Code |
A1 |
Song, In-Duk ; et
al. |
July 28, 2005 |
Liquid crystal display device having stripe-shaped color
filters
Abstract
A liquid crystal display device has stripe-shaped color filters
and arranges the driver ICs on the top or the bottom side portion,
and on the left or right side portion of the liquid crystal panel
such that the liquid crystal display device has a single bank
structure. Accordingly, a difference of a signal delay between the
adjacent two odd and even data or gate lines is prevented. As a
result, the brightness and the resolution are improved.
Inventors: |
Song, In-Duk; (US) ;
Chung, In-Jae; (US) |
Correspondence
Address: |
MCKENNA LONG & ALDRIDGE LLP
1900 K STREET, NW
WASHINGTON
DC
20006
US
|
Family ID: |
19647585 |
Appl. No.: |
10/985910 |
Filed: |
November 12, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10985910 |
Nov 12, 2004 |
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09784093 |
Feb 16, 2001 |
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6833888 |
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Current U.S.
Class: |
345/88 |
Current CPC
Class: |
G09G 2320/0223 20130101;
G09G 3/3607 20130101; G09G 3/3648 20130101; G02F 2201/52
20130101 |
Class at
Publication: |
345/088 |
International
Class: |
G09G 003/36 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 18, 2000 |
KR |
2000-7715 |
Claims
1-6. (canceled)
7. A method of fabricating a liquid crystal display device,
comprising: forming a plurality of gate and data lines on a first
substrate; forming a black matrix on a second substrate; forming
open portions for color filters by patterning the black matrix;
depositing a resin on the black matrix covering the open portions,
wherein the resin has one of red, green, blue and white colors;
forming color filters in the open portions by photolithography, the
color filters having a stripe shape; forming a liquid crystal panel
by combining the first and second substrates with interposed liquid
crystal; installing data driver integrated circuits (ICs) on one
side portion of the liquid crystal panel, wherein the data driver
ICs drive the plural data lines; and installing gate driver
integrated circuits (ICs) on one side portion of the liquid crystal
panel, wherein the gate driver ICs drive the plural gate lines.
8. A method according to claim 7, wherein the stripe-shaped color
filter having a white color is made of a transparent resin.
9. A method according to claim 7, wherein the stripe-shaped color
filter having a white color is an open portion of the black
matrix.
10-15. (canceled)
16. A method of driving a liquid crystal panel, including a first
substrate having deposited thereon a plurality of stripe-shaped
color filters and a black matrix arranged around the stripe-shaped
color filters, wherein each color filter has one of red, green,
blue and white colors, and including a second substrate disposed
opposing the first substrate and having a plurality of gate lines
arranged in a transverse direction, a plurality of data lines
arranged in a longitudinal direction and a plurality of sub-pixels
each formed at an intersection of one of the gate lines and data
lines, and further including a liquid crystal material deposited
between the first and second substrates, the method comprising:
driving the data lines, each data line driving sub-pixels
corresponding to a same one of the red, green, blue of white
colors; driving the gate lines, alternating a polarity of a gate
line driving signal for each of the gate lines at each frame
interval.
17. The method of claim 16, further comprising alternating
polarities of the gate line driving signals for adjacent gate lines
during a same frame interval.
Description
[0001] This application claims the benefit of Korean Patent
Application No. 2000-7715, filed on Feb. 18, 2000, which is hereby
incorporated by reference for all purposes as if fully set forth
herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a liquid crystal display
(LCD) device, and more particularly, to a LCD device having color
filters arranged in a stripe shape.
[0004] 2. Discussion of the Related Art
[0005] In general, the LCD device includes a liquid crystal panel
having upper and lower substrates and an interposed liquid crystal
layer. The upper substrate, referred to as a color filter
substrate, includes a common electrode and color filters. The lower
substrate is called an array substrate and includes gate lines
arranged in a transverse direction and data lines arranged in a
longitudinal direction perpendicular to the gate lines. A pixel
electrode is formed on a region of the lower substrate defined by
the gate and data lines. Thin film transistors (TFTs) are formed as
switching elements at a crossing point of the gate and data lines
in a matrix. Each of the TFTs includes a gate electrode, a source
electrode and a drain electrode. The drain electrode contacts the
pixel electrode via a drain contact hole. Peripheral portions of
the two substrates are sealed by a sealant to prevent liquid
crystal leakage. The gate lines serve to transmit scanning signals
to the gate electrodes, and the data lines serve to transmit data
signals to the source electrodes. The data signals change
alignments of the liquid crystal molecules according to the
scanning signals such that the LCD device displays various gray
levels.
[0006] In such an LCD device, a driver integrated circuit (IC) that
applies signals to each electrode through each line on the lower
substrate may be mounted using various methods, for example, chip
on board (COB), chip on glass (COG), tape carrier package (TCP),
and the like.
[0007] The COB method is conventionally adopted for a segment type
LCD device, or a LCD panel having a low resolution. Since the
segment type LCD device or the low resolution LCD panel uses a
small number of leads, the driver IC thereof has also a small
number of leads. Therefore, the driver IC thereof is first
installed on a printed circuit board (PCB) having a plurality of
leads, and the leads of the PCB are connected with the LCD panel
via a proper method, which is relatively simple.
[0008] However, as the LCD devices have high resolutions, a great
number of leads are adopted for the driver IC. When the driver IC
has a great number of leads, it is difficult to install the driver
IC on the above-mentioned PCB.
[0009] In another method, the COG method, the driver IC is directly
installed on the LCD panel without interposing the PCB. Therefore,
the connection between the driver IC and the LCD panel is stable,
and a minute pitch is applicable for the installation of the driver
IC. The COG method employs a multi-layered flexible printed circuit
board (FPCB) instead of the PCB. The multi-layered FPCB contacts
the LCD panel via an anisotropic conductive film (ACF) and
transmits input signals to the driver IC.
[0010] The above-mentioned COG method has advantages of low cost
and high stability. However, since a pad of the LCD panel needs an
additional area to install the driver IC, the LCD panel should be
enlarged. In addition, when the COG method is adopted for the LCD
panel, it is difficult to repair defects of the driver IC or
terminal lines of the LCD panel.
[0011] In another method, the TCP method, the driver IC is
installed on a polymer film. The TCP method is widely used for LCD
devices as well as mobile phones that need small, thin, and light
electrical packages.
[0012] FIG. 1 is a cross-sectional view illustrating a liquid
crystal panel having a driver IC mounted thereon using the TCP
technique. As shown in FIG. 1, a driver IC 17 is mounted on a
polymer film 19, and the polymer film 19 having the driver IC 17 is
connected with both a lower substrate 11 and a printed circuit
board 15 through an anisotropic conductive film (ACF) 18. Signals
are applied through such a tape carrier package from one or each
end portion of gate and data lines (not shown) in order to drive
the liquid crystal panel having the lower and upper substrates 11
and 13.
[0013] FIG. 3 is a plan view illustrating a conventional quad type
color LCD device. A liquid crystal panel 111 generally includes a
number of dots, and each unit pixel includes four sub-pixels or
dots: an RGBW (red, green, blue, and white) arrangement as shown in
FIG. 3 or an RGGB (red, green, green, and blue) arrangement (not
shown).
[0014] In a large-sized LCD device employing the TFT as a switching
element, when a direct current bias is applied to the liquid
crystal layer, the liquid crystal layer can deteriorate. Thus, it
is preferable to change a polarity of a voltage applied to the
liquid crystal layer for each frame. Such inversion driving methods
are classified into frame inversion, column inversion, line
inversion, and dot inversion.
[0015] FIGS. 2A to 2D are plan views illustrating the four
inversion methods mentioned above. In the frame inversion driving
method, as shown in FIG. 2A, all of the sub-pixels receive signals
of the same polarity in one frame and in next frame all of the
sub-pixels receive signals of inverse polarity. FIG. 2B illustrates
the column inversion driving method, that sub-pixels of every other
column receive the signals of the same polarity and the polarity of
the signal is changed at the next frame. FIG. 2C illustrates the
line inversion driving method, that sub-pixels of every other line
(row direction) receive the signals of the same polarity and the
polarity of the signal is changed at the next frame. FIG. 2D
illustrates the dot inversion driving method. In the dot inversion
drive method, the drive voltages applied to the pixel electrodes
are such that the polarities of two adjacent pixel electrodes,
which are disposed adjacent to each other in either the column or
row direction, are opposite to each other with respect to the
counter electrode. In other words, the polarities of the pixel
electrodes with respect to the counter electrodes alternate as
viewed along both the column direction and the row direction in
each instance.
[0016] Through such inversion methods, cross talk and flickering of
a screen can be reduced and a large-sized color LCD device is
driven using such a method.
[0017] In order to drive the LCD device, gate driver ICs and data
driver ICs, which are respectively connected with data lines and
gate lines, are mounted to the liquid crystal panel through various
method described above. Further, the LCD device employs either a
dual bank structure or a single bank structure to drive the liquid
crystal layer. In the dual bank structure, the data driver ICs are
arranged on both top and bottom side portions of the liquid crystal
panel, or the gate driver ICs are arranged on both right and left
side portions of the liquid crystal panel. In the single bank
structure, the data driver ICs are all arranged on either the top
or the bottom portion of the liquid crystal panel, or the gate
driver ICs are all arranged on either the right or left portion of
the liquid crystal panel.
[0018] As shown in FIG. 3, the liquid crystal panel 111 adopts the
dual bank structure that has a plurality of the driver ICs at all
four sides of the liquid crystal panel. Namely, the data driver ICs
115a and 115b that apply the data signals to the data lines 119 are
arranged on both top and bottom portion of the liquid crystal panel
111, and the gate driver ICs 113a and 113b that apply the scanning
signals to the gate lines 117 are arranged on both left and right
side portions of the liquid crystal panel 111. For a more detailed
explanation, the two gate driver ICs 113a are arranged on a left
side portion of the liquid crystal panel 111, and two gate driver
ICs 113b are arranged on a right side portion of the liquid crystal
panel 11 in the dual bank structure. Also, the four data driver ICs
115a are arranged in the top portion of the liquid crystal panel
111, and the four data driver ICs 115b are arranged in the bottom
portion of the liquid crystal display panel 111 in the dual bank
structure. The liquid crystal display panel 111 can employ the dot
inversion driving method or the frame inversion driving method
which are described above. An external controller controls such
driving methods.
[0019] At this time, according to the dual bank stricture, each of
the gate driver ICs 113a and 113b formed respectively on left and
right sides portion of the liquid crystal panel 111 operate the
even or odd numbered gate lines, respectively. Moreover, each of
the data driver ICs 115a and 115b formed respectively on top and
bottom side portions of the liquid crystal panel 111 operate the
even or odd numbered data lines, respectively. For that reason, a
signal difference is created between adjacent lines.
[0020] FIG. 4 is a plan view illustrating data signal transmissions
of the liquid crystal panel having a dual bank structure according
to a conventional art. As shown in FIG. 4, the data driver ICs 115a
are arranged at the top side portion of the liquid crystal panel
111 to drive odd numbered data line 121, and the data driver ICs
115b are arranged at the bottom side portion of the liquid crystal
panel to drive even numbered data line 123. Therefore, a difference
of a signal delay caused by a line resistance may occur between the
odd and even numbered data lines. For example, a difference of a
signal delay between the two adjacent odd and even data lines may
occur at portions A and A'. As a result, optical characteristics of
the pixel may vary, whereby defects causing a brightness difference
may occur at the portions A and A'.
SUMMARY OF THE INVENTION
[0021] Accordingly, the present invention is directed to a liquid
crystal display device having stripe-shaped color filters that
substantially obviates one or more of the problems due to
limitations and disadvantages of the related art.
[0022] To overcome the problems described above, a preferred
embodiment of the present invention provides a liquid crystal
display device which arranges color filters in a stripe shape.
[0023] Another object of the present invention is to provide the
liquid crystal display device having a high brightness and
resolution.
[0024] 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.
[0025] In order to achieve the above object, the preferred
embodiments of the present invention provide a liquid crystal
display device, including: a liquid crystal panel having a
plurality of gate and data lines and a plurality of sub-pixels,
wherein the gate lines are arranged in a transverse direction and
the data lines are arranged in a longitudinal direction, wherein
each sub-pixel is defined by the gate and data lines and
corresponds to a stripe-shaped color filter that has one of red,
green, blue and white colors; a black matrix arranged among the
stripe-shaped color filters; a gate driver integrated circuit (IC)
connected to the plural gate lines for driving the gate lines, the
gate driver IC arranged on one side portion of the liquid crystal
panel; and a data driver integrated circuit (IC) connected to the
plural data lines for driving the data lines, the data driver IC
arranged on one side portion of the liquid crystal panel.
[0026] Each stripe-shaped color filter can have one of red, green,
green and blue colors. The stripe-shaped color filter having a
white color is made of a transparent resin, or the stripe-shaped
color filter having a white color is a open portion of the black
matrix.
[0027] The principles of the present invention further provide a
method of fabricating a liquid crystal display device, beneficially
including: forming a plurality of gate and data lines on a first
substrate; forming a black matrix on a second substrate; forming
open portions for color filters by patterning the black matrix;
depositing a resin on the black matrix covering the open portions,
wherein the resin has one of red, green, blue and white colors;
forming color filters in the open portions by photolithography, the
color filters having a stripe shape; forming a liquid crystal panel
by combining the first and second substrates with interposed liquid
crystal; installing data driver integrated circuits (ICs) on a top
or bottom side portion of the liquid crystal panel, wherein the
data driver ICs drive the plural data lines; and installing gate
driver integrated circuits (ICs) on one side portion of the liquid
crystal panel, wherein the gate driver ICs drive the plural gate
lines.
[0028] 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.
BRIEF DESCRIPTION OF THE DRAWING
[0029] The accompanying drawings, which are included to provide a
further understanding of the invention and are incorporated in and
constitute a part of this specification, illustrate embodiments of
the invention and together with the description serve to explain
the principles of the invention.
[0030] In the drawings:
[0031] FIG. 1 is a cross-sectional view illustrating a typical
liquid crystal panel mounting a driver IC using the TCP
technique;
[0032] FIGS. 2A to 2D are plan views illustrating, respectively, a
frame inversion driving method, a column inversion driving method,
a line inversion driving method, and a dot inversion driving
method;
[0033] FIG. 3 is a plan view illustrating a quad type liquid
crystal display device according to a conventional art;
[0034] FIG. 4 is a plan view illustrating a configuration of a
liquid crystal panel having a dual bank structure according to a
conventional art;
[0035] FIG. 5 is a schematic perspective view illustrating an
arrangement of color filters in a stripe shape according to a
preferred embodiment;
[0036] FIGS. 6A and 6B are plan views illustrating fabrication
steps of stripe-shaped color filters according to the preferred
embodiment;
[0037] FIG. 7 is a schematic plan view illustrating configuration
of the liquid crystal display device having stripe-shaped color
filters according to the preferred embodiment; and
[0038] FIG. 8 illustrates line inversion driving in accordance with
the preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0039] Reference will now be made in detail to the preferred
embodiment, an example of which is illustrated in the accompanying
drawings.
[0040] FIG. 5 is a schematic perspective view illustrating an
arrangement of color filters in a stripe shape according to a
preferred embodiment. As shown, the color filters 211 are formed on
a substrate 310 and are arranged in a stripe shape. Each color
filter has a red, green, blue or white color.
[0041] FIGS. 6A and 6B are plan views illustrating fabrication
steps of stripe-shaped color filters according to the preferred
embodiment.
[0042] Referring to FIG. 6A, chrome oxide (CrO.sub.x) and chrome
(Cr) are deposited in series on the substrate 310. These materials
finally form a black matrix 313. The open portions 311 for the
color filters are formed by patterning the black matrix 313 using a
photolithography process. Thus, the black matrix 313 is arranged
among the open portions 311 and prevents the light from leaking,
and thus the black matrix 313 raises the contrast ratio of the
liquid crystal display. The black matrix 313 is usually made of
chrome (Cr), but it can be made of an organic substance.
[0043] Referring to FIG. 6B, a resin having reddish colored pigment
is deposited on the black matrix 313 and in the open portions 311
(see FIG. 6A). After that, color resist is formed on the open
portions 311, and the red color filters 411 are then formed by
patterning the resin using the photolithography process. Through
repeating these processes, the green and blue color filters are
formed and thus the RGBW (red, green, blue and white) color filters
having a stripe shape is complete.
[0044] When forming the white color filters 413, the open portions
311 are used "as-is." Namely, the open portions 311 without any
resin are used as the white color filters 413. Alternatively,
transparent resin can also be used as the white color filters
413.
[0045] Accordingly, the color filter substrate fabricated according
to the above-mentioned method is adhered to the array substrate
having the switching elements and the plural lines. The liquid
crystal is interposed between the pair of substrates, and thus the
liquid crystal panel is completed. After that, the data driver ICs
and the gate driver ICs are installed between that liquid crystal
panel and the PCB via a proper method. Thus, the LCD device is
complete.
[0046] FIG. 7 is a schematic plan view illustrating configuration
of the liquid crystal display device having stripe-shaped color
filters according to the preferred embodiment. As shown, in the
liquid crystal display device 511, the data driver ICs 513 can be
arranged on either the top or bottom side portions of the liquid
crystal panel, and the gate driver ICs 515 can also be arranged on
either the right or left side portions. At this point, positive (+)
polarity signals are applied to the sub-pixels that are connected
with the odd numbered gate lines contacting the gate driver ICs
515. And the negative (-) polarity signals are applied to the
sub-pixels that are connected with the even numbered gate lines.
Thus, each sub-pixel of the liquid crystal panel is operated by
these signals. And thus, the line inversion driving method
according to the embodiment is as shown in FIG. 8.
[0047] As described above, since the embodiment has the RGBW (red,
green, blue and white) or RGGB (red, green, green, and blue) color
filters in a stripe shape, the liquid crystal panel is operable in
the single bank type. Thus, a difference of a signal delay between
the two adjacent odd and even data or gate lines is prevented. As a
result, the brightness and the resolution of the liquid crystal
display are improved.
[0048] It will be apparent to those skilled in the art that various
modifications and variations can be made in the present invention
without departing from the spirit or scope of the invention. Thus,
it is intended that the present invention cover the modifications
and variations of this invention provided they come within the
scope of the appended claims and their equivalents.
* * * * *