JPH1073810A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To preform the display of a high-picture quality in which a color unevenness is not present by dissolving the turbulence of an electric field. SOLUTION: This liquid crystal display device is provided with color filters of not less than two kinds formed on the substrate of one side of substrates 1, 1', black masks interposed between respective color filters, electrode groups 2, 11 formed on the substrate of other side, orientation control films 20, 20' for orienting molecular arrangements of liquid crystal moleculars held between the substrates. polarizing, means 13, 13' laminated on the substrates and driving means for impressing driving voltages on the electrode group and has an electrode arrangement structure mainly forming electric fields parallel with respect to boundary planes between the orientation control films and a liquid crystal layer and the specific resistance value of each black mask is made to be >=10MΩ.cm (M is an integer) and also to be a relation satisfying M>8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high quality thin film transistor type liquid crystal display device having a pixel structure without display unevenness.

[0002]

2. Description of the Related Art In recent years, thin, lightweight and low power consumption display devices using liquid crystal display devices have been frequently used as display devices for personal computers, word processors, and other information devices.

A liquid crystal display device basically has a matrix formed by a large number of electrodes arranged horizontally and vertically and a liquid crystal layer between the horizontal and vertical electrodes, and has a liquid crystal layer at the intersection of the two electrodes. A two-dimensional image is displayed by forming pixels.

This type of liquid crystal display device has a so-called simple matrix system in which predetermined pixels are selected at the timing of pulses applied to horizontal and vertical electrodes, and a non-linear device such as a transistor arranged in each image. There is a so-called active matrix method for selecting a non-linear element.

An active matrix type liquid crystal display device has a non-linear element (switching element) corresponding to each of a plurality of pixel electrodes arranged in a matrix. Since the liquid crystal in each pixel is theoretically always driven (duty ratio: 1.0), the active method has a better contrast than the so-called simple matrix method which adopts the time-division driving method, and particularly the color liquid crystal. It is becoming an indispensable technology for display devices. A typical switching element is a thin film transistor (TFT).

In a conventional thin film transistor type liquid crystal display device , transparent electrodes formed opposite to each other on an interface between two substrates are used as electrodes for driving a liquid crystal layer.

With such an electrode structure, a display system represented by a so-called twisted nematic display system in which the direction of the electric field applied to the liquid crystal is substantially perpendicular to the interface of the substrate is adopted.

On the other hand, as a display system in which the direction of the electric field applied to the liquid crystal is substantially parallel to the interface of the substrate, an electrode for driving the liquid crystal layer uses a pair of comb-teeth electrodes parallel to the substrate surface (so-called horizontal). Electric field method), for example,
7 and JP-A-7-36058. A method for setting and manufacturing a comb-shaped electrode has been filed by the present applicant as Japanese Patent Application No. 7-105862.

FIG. 9 is a schematic cross-sectional view for explaining the structure and lighting operation of one pixel constituting a liquid crystal display device of the horizontal electric field type, wherein 1 is a TFT substrate, 1 'is a color filter substrate, 2 is a common electrode, Reference numeral 6 denotes an insulating film, 11 denotes a pixel electrode, 12 denotes a protective film, 17 denotes a black mask, and 18 denotes a color filter.

In FIG. 1, a liquid crystal layer is sandwiched between a TFT substrate 1 and a color filter substrate 1 ′. Further, on the upper surfaces of the protective film 12 and the color filter 18, the alignment direction of liquid crystal molecules constituting the liquid crystal layer is provided. A polarizing plate is provided on the outer surface side of the TFT substrate 1 and the color filter substrate 1 'for defining the alignment film, but is not shown.

In the in-plane switching mode liquid crystal display device having such a configuration, both the pixel electrode 2 and the common electrode 11 are connected to one substrate (T.sub.T).
The color filter 18 is formed on the FT substrate 1), and the other substrate (color filter substrate 1 ′) is provided with a color filter 18 that constitutes the color of one pixel partitioned by the black mask 17.

The black mask 17 for partitioning the color filter has a function of preventing reflection of external light and absorbing light from an adjacent pixel to increase the contrast. The material is a slurry (resist) in which graphite is dispersed in a pigment. It is common to form using.

[0013]

In a conventional vertical electric field type liquid crystal display device in which a common electrode is formed on the color filter substrate side, the performance required of the black mask constituting the color filter substrate is high light absorption. It has low light reflectivity, and its resistance was not considered at all.
In a black mask using the above-described material, the amount of graphite added has been increased particularly in an attempt to improve light absorption. Therefore, its resistance value decreases as the amount of graphite added increases.

However, in a horizontal electric field type liquid crystal display device, if the resistance value of the black mask is low, a voltage is applied between the pixel electrode 2 and the common electrode 11 to light the pixel as shown in FIG. Is applied, the lines of electric force from the pixel electrode 2 become black masks 17 having a low resistance value as shown in FIG.
To form a disturbed electric field pattern inclined with respect to the substrate interface. As a result, the pixel electrode 2 and the common electrode 12
A so-called domain is generated at the position, and the light transmittance is significantly reduced. For this reason, the contrast is reduced, and color unevenness occurs, so that it is impossible to obtain a good image quality display.
Alternatively, the horizontal component of the line of electric force is weakened, and a desired transmittance cannot be obtained.

At present, it is most desirable to use graphite as a material constituting the black mask from the viewpoint of light absorption. However, when the amount of the mixture is increased, the electric resistance value decreases,
Since the above-described problems occur, it is extremely difficult to select the mixing ratio.

FIGS. 10A and 10B are schematic diagrams of one pixel of a lateral electric field type liquid crystal display device in which two comb-shaped common electrodes are arranged in one pixel. FIG. 10A is a plan view, and FIG. 2) is a cross-sectional view taken along line AA. Note that a color filter is provided in a portion surrounded by the black mask 17, and an upper layer,
Various films are also formed on the common electrode 2 and the pixel electrode 11, but they are omitted here.

In FIG. 1, one pixel is formed in an opening area surrounded by a black mask, and two comb-shaped common electrodes 2 are disposed in the area, and a pixel is formed between the TFT substrate 1 and the color filter substrate 1 '. The liquid crystal layer is sandwiched between them. The specific resistance of the black mask is 10 ⁴ Ω · cm or less.

An electric field is formed between the common electrode 2 and each adjacent pixel electrode 11 by a signal voltage applied at the time of lighting. This electric field strongly acts on the liquid crystal molecules in accordance with the magnitude of the applied signal voltage, and the direction of the molecular orientation is rotated to move the TFT substrate 1 from the color filter substrate 1 ′.
The transmittance of the light passing through becomes larger.

FIG. 11 is a diagram for explaining the difference between the transmittance between the two comb-shaped common electrodes shown in FIG. 10 and the transmittance between each comb-shaped common electrode and an adjacent pixel electrode. a
Represents the transmittance between two comb-shaped common electrodes, and the spot b represents the change in transmittance between each comb-shaped common electrode and an adjacent pixel electrode.

As shown in FIG. 2, the transmittance increases as the signal voltage (V) applied to the pixel electrode 11 increases, but as shown in FIG. Since the electric field pattern is formed at a large angle with respect to the plane of the substrate because it is located near the mask 17, the rise of the change in the transmittance with respect to the increase in the voltage is slower than that of the spot a. In FIG. 11, in order to obtain the same transmittance, spot a
Requires a voltage increase of about 1V.

Therefore, with the same applied voltage, the transmittance differs between the central portion and the peripheral portion within one pixel, and color unevenness occurs.

An object of the present invention is to eliminate the above-mentioned disturbance of the electric field pattern in a so-called horizontal electric field type liquid crystal display device,
An object of the present invention is to provide a thin film transistor type liquid crystal display device capable of displaying high quality images without color unevenness.

[0023]

In order to achieve the above object, the present invention provides (1) at least one of a pair of transparent substrates, and a color display for color display formed on one of the pair of substrates. At least two or more different color filters, a black mask interposed between the color filters, an electrode group formed on the other of the pair of substrates, and a dielectric layer sandwiched between the pair of substrates. A liquid crystal layer made of a liquid crystal composition material having anisotropy, an alignment control film for aligning a molecular arrangement of the liquid crystal composition material in a predetermined direction, a polarizing means laminated on at least one of the pair of substrates, and the electrode The electrode group of the color liquid crystal display device including a driving unit for applying a driving voltage to the group forms an electric field mainly parallel to an interface between the alignment control film and the liquid crystal layer. Has especially arranged electrode arrangement structure, specific resistance of the liquid crystal composition material 10 ^N Ω · cm or more, a specific resistance value of the black mask 10 ^M Ω · cm or more, however, N, M are integers, In addition, the relationship should satisfy N> 9 and M> 6. And (2) a pair of substrates at least one of which is transparent, at least two or more kinds of color filters having different colors for color display formed on one of the pair of substrates, and a black mask interposed between the color filters. An electrode group formed on the other of the pair of substrates, a liquid crystal layer made of a liquid crystal composition having dielectric anisotropy sandwiched between the pair of substrates, and a molecular arrangement of the liquid crystal composition. A liquid crystal display device comprising: an alignment control film for orienting the substrate in a predetermined direction; polarizing means laminated on at least one of the pair of substrates; and driving means for applying a driving voltage to the electrode group. The electrode group has an electrode arrangement structure arranged so as to form an electric field mainly parallel to the interface between the alignment control film and the liquid crystal layer, and the ratio of the liquid crystal composition material Anti-value is 10
^N Ω · cm or more, and the specific resistance of the black mask is 10
^M Ω · cm or more, where N and M are integers and N> 1
The main point is that a relationship satisfying M> 7 is satisfied.

That is, in the first aspect of the present invention, at least one of the pair of substrates is transparent, the black mask formed on one of the pair of substrates, and the pair of substrates are sandwiched between the pair of substrates. In a thin film transistor type liquid crystal display device having a liquid crystal layer made of a liquid crystal composition material having a dielectric anisotropy, a direction of an electric field applied to the liquid crystal layer is:
The black mask has a direction substantially parallel to the substrate, and the black mask has a specific resistance of 10 ⁸ Ω · cm or more.

According to a second aspect of the present invention, the electrode group formed on one of the pair of substrates and the molecular arrangement of the liquid crystal composition material are determined. Wherein the electrode group has an electrode arrangement structure in which an electric field is mainly formed parallel to the interface between the alignment film and the liquid crystal layer.

According to a third aspect of the present invention, in the first aspect, the black mask has at least two or more kinds of different colors for color display formed on one of the pair of substrates. It is characterized by being arranged between color filters.

According to a fourth aspect of the present invention, a plurality of pixels arranged in a matrix are formed on the one substrate in the second aspect, and the black mask is formed on the other substrate. It is characterized by that.

According to a fifth aspect of the present invention, the electrode group according to the second aspect includes at least a common electrode and a pixel electrode.

According to a sixth aspect of the present invention, there is provided a driving apparatus for applying a driving voltage to the electrode group according to the fifth aspect.

A seventh aspect of the present invention is characterized in that a resist in which graphite is dispersed is used as the material of the black mask in the first aspect.

Further, an eighth invention according to claim 8 is a semiconductor device comprising:
A personal computer on which the thin film transistor type liquid crystal display device according to claim 1 is mounted.

A ninth aspect of the present invention is directed to
A pair of substrates at least one of which is transparent, at least two or more kinds of color filters having different colors for color display formed on one of the pair of substrates, and a black mask interposed between the color filters; An electrode group formed on the other substrate of the pair of substrates, a liquid crystal layer made of a liquid crystal composition having dielectric anisotropy sandwiched between the pair of substrates, and a liquid crystal composition having a predetermined molecular arrangement. A liquid crystal display device comprising: an alignment control film for orienting in the direction of; a polarizing unit laminated on at least one of the pair of substrates; and a driving unit for applying a driving voltage to the electrode group. An electrode arrangement structure in which the electrode group is arranged so as to form an electric field mainly parallel to the interface between the alignment control film and the liquid crystal layer,
Resistivity of the black mask 10 ^M Ω · cm or more,
Here, M is an integer, and a relationship satisfying M> 8 is set.

The present invention is not limited to the TFT type, but can be applied to other types of liquid crystal display devices including other active matrix types or a so-called simple matrix type.

In the structure of the present invention, the black mask interposed between at least two or more kinds of color filters having different colors for color display and formed on one of a pair of transparent substrates at least one of which is adjacent. The illumination light of the pixel is prevented from entering, and the contrast of the display light is improved.

An electrode group formed on the other substrate of the pair of substrates includes at least a common electrode and a pixel electrode, and forms a liquid crystal layer by forming an electric field pattern between the two electrodes during lighting. Is rotated to change the light transmittance.

The orientation control film (orientation film) has the function of orienting the molecular arrangement of the liquid crystal composition in a predetermined direction when no electric field is applied. In addition, the polarizing means is laminated on at least one of the pair of substrates and transmits light polarized in a specific direction passing through the liquid crystal layer.

The driving means applies a driving voltage to the electrode group to turn on a predetermined pixel to perform color display.

The electrode structure of the electrode group is arranged so as to form an electric field mainly parallel to the interface between the alignment control layer and the liquid crystal layer, and is arranged between the common electrode and the pixel electrode constituting the electrode group. When the electric field is formed, the liquid crystal molecules are rotated in a plane parallel to the interface.

Then, the specific resistance value of the liquid crystal composition material is set to 1
0 ^N Ω · cm or more, a specific resistance value of the black mask 1
And 0 ^M Ω · cm or more (However, N, M is an integer), N>
9, the parallel electric field is formed by satisfying the relationship of M> 6.

As a result, the liquid crystal molecules rotate in a plane parallel to the interface, and so-called domains do not occur.

In the structure of the present invention, the black mask interposed between at least two or more kinds of color filters having different colors for color display and formed on one of a pair of transparent substrates, The contrast of display light is improved by blocking the intrusion of lighting light of adjacent pixels.

An electrode group formed on the other of the pair of substrates is composed of at least a common electrode and a pixel electrode, and forms a liquid crystal layer by forming an electric field pattern between the two electrodes during lighting. Is rotated to change the light transmittance.

The alignment control layer has a function of aligning the molecular arrangement of the liquid crystal composition material in a predetermined direction when no electric field is applied. In addition, the polarizing means is laminated on at least one of the pair of substrates and transmits light polarized in a specific direction passing through the liquid crystal layer.

The driving means applies a driving voltage to the electrode group to turn on a predetermined pixel to perform color display.

The electrode structure of the electrode group is arranged so that an electric field mainly parallel to the interface between the alignment control layer and the liquid crystal layer is formed, and the electrode structure is formed between the common electrode and the pixel electrode constituting the electrode group. When the electric field is formed, the liquid crystal molecules are rotated in a plane parallel to the interface.

The specific resistance value of the liquid crystal composition material is set to 1
0 ^N Ω · cm or more, a specific resistance value of the black mask 1
And 0 ^M Ω · cm or more (However, N, M is an integer), N>
13, the parallel electric field is formed by satisfying the relationship of M> 7.

As a result, the liquid crystal molecules rotate in a plane parallel to the interface, and so-called domains do not occur.

[0048]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to examples.

FIG. 1 is a schematic diagram of one pixel for explaining the operation of a liquid crystal display device to which the present invention is applied. FIG. 1A is a cross-sectional view when no voltage is applied, and FIG. FIG. 4C is a cross-sectional view when voltage is applied, FIG. 4C is a plan view when no voltage is applied, and FIG. 5D is a plan view when voltage is applied. The voltage referred to here is a selection voltage applied between the common electrode and the pixel electrode.

In the figure, reference numerals 1 and 1 ′ denote transparent glass substrates (hereinafter also simply referred to as substrates), 2 denotes a common electrode, 6 denotes an insulating film, 10 denotes a signal wiring, 11 denotes a pixel electrode, 12 denotes a protective film,
13, 13 'are polarizing plates, 14 and 14' are polarizing axes of the polarizing plates, 15 is an alignment direction of liquid crystal molecules, 16 is an electric field direction, 17 is an electric field direction.
Is a black mask (BM), 18 is a color filter, 1
9 is a protective film (planarization film), 20 and 20 ′ are alignment films, 21
Is a liquid crystal (rod-like liquid crystal molecule).

In this liquid crystal display device, a polarizing plate 13 ', a BM 17 for shielding light, and a color filter 1 are provided on one of two transparent glass substrates 1 and 1' (color filter substrate) 1 '.
8, a protective film 19, and an alignment film 20 'are formed.
On the other substrate (TFT substrate) 1 via the liquid crystal 21, a polarizing plate 13, an alignment film 20, a signal electrode 10, a pixel electrode 1
1, common electrode 2, each wiring and thin film transistor (TF
T). It should be noted that illustration of each wiring and thin film transistor is omitted in FIG.

As shown in FIGS. 7A and 7C, the liquid crystal 2
1 is preliminarily oriented by the orientation films 20 and 20 ′ in the electric field direction 16 (see FIGS. 3B and 3D) and in the orientation direction 15 substantially parallel to the interface between the substrates 1 and 1 ′.
Has a relationship substantially coincident with the polarization axis 14 of the polarizing plate 13, the polarization axis 14 'of the upper polarizing plate 13' is orthogonal, and the pixel is in a non-display (non-lighting) state.

Next, as shown in FIGS.
When an electric field (electric field direction 16) is formed in a direction substantially parallel to the interface between the substrates 1 and 1 'by applying a voltage between the common electrode 2 and the pixel electrode 11 formed on the substrate 1, the molecules of the liquid crystal 21 It is deflected and rotated in a plane parallel to the interface 1 ′.
As a result, the pixel enters a display (lighting) state. A display device is configured by arranging a large number of these pixels.

FIG. 2 is an explanatory view of a structural example of a TFT substrate constituting one embodiment of the liquid crystal display device according to the present invention.
(A) is a plan view, (b) is a cross-sectional view taken along line AA 'of (a), and (c) is a cross-sectional view taken along line BB' of (a).

In the figure, the same reference numerals as those in FIG. 1 correspond to the same portions, 3 is a common wiring, 4 is a scanning electrode, 5 is a scanning wiring, 6 is an insulating film, 7 is a semiconductor layer, and 8 is a thin film transistor portion ( TFT part), 10 is a signal wiring, 11 is a pixel electrode,
Reference numeral 12 denotes a protective film.

The scanning electrode 4, the scanning wiring 5, the common electrode 2 and the common wiring 3 are formed of the same layer and of the same material. The semiconductor layer 7 is formed via these layers and the insulating film 6, and the signal wiring 10 and the pixel electrode 11 are formed of the same layer and the same material as the above-mentioned electrodes and wiring.

Further, a part of the pixel electrode 11 is disposed so as to overlap with the common wiring 3 in a direction perpendicular to the substrate surface via the insulating film 6 so that the pixel electrode 11 and the common electrode 2 have electric capacitance. The signal holding ability of holding the signal voltage given during the period is improved.

FIG. 3 is an explanatory view of a structural example of a color filter substrate constituting one embodiment of the liquid crystal display device according to the present invention, and the same reference numerals as those in FIG. 1 correspond to the same parts.

As shown in the figure, a plurality of color filters (R, G, B) partitioned by a BM 17 are formed on one side of a transparent substrate 1 'of this color filter substrate, and a protective film (smooth) is formed thereon. Layer 19) and an alignment film 20 '. Further, a polarizing plate 13 'is laminated on the other surface side of the transparent substrate 1'.

[0060] a plurality of color filters R, G, specific resistance of the BM17 defining the B is the specific resistance of the liquid crystal layer 10 ^N Omega ·
in case of the above cm, a 10 ^M Ω · cm or more and have a relationship to satisfy the N> 9, M> 6. Here, N and M are integers.

By setting the specific resistance value of the liquid crystal layer and the BM to the above-described relationship, the electric field pattern formed by the selection voltage applied between the common electrode and the pixel electrode becomes the electric field pattern of the liquid crystal layer and the alignment film. It is substantially parallel to the interface, and the generation of domains is significantly reduced, and a high-contrast display is obtained.

That is, FIG. 4 is a schematic view of an electric field pattern in a cross section of one pixel constituting one embodiment of the liquid crystal display device according to the present invention, which is formed between the common electrode 2 and the pixel electrode 11. The lines of electric force are not affected by the BM 17 and the electric field pattern is substantially parallel to the interface between the liquid crystal layer and the alignment film, and the position of the pixel electrode 11 and the common electrode 2
, The occurrence of each domain at the position is significantly reduced, the transmittance in the opening region of one pixel is improved, and a high-contrast display is obtained.

[0063] Incidentally, the resistivity of the liquid crystal layer 10 ^N Ω · cm
Above, the specific resistance value of the BM 10 ^M Ω · cm or more (N, M is an integer) and, N> 13, the same effect as described above can be obtained as M> 7.

As the material of the black mask, a mixture of carbon and an organic pigment is used, and the amount of the carbon is adjusted so as to be in the above-described required specific resistance range.

FIG. 5 is an explanatory diagram of the relationship between the specific resistance of the BM and the driving voltage when the specific resistance of the liquid crystal layer and the BM is changed in each embodiment of the present invention.

In the figure, the permissible change in the transmittance with respect to the change in the driving voltage is 0.1 V or less. When the specific resistance of the liquid crystal is 10 ⁹ Ω · cm, the specific resistance of the BM is 3 × 10 ⁶ Ω.
· Cm, and B when the specific resistance of the liquid crystal is 10 ¹³ Ω · cm
The specific resistance of M is 5 × 10 ⁷ Ω · cm.

From this, it can be seen that N> 9, M> 6,
The effects described above can be obtained by setting N> 13 and M> 7.

As the material of the black mask, a material obtained by mixing carbon with an organic pigment as described above is used, and the carbon mixing ratio can be adjusted so as to be in the above-described range of the specific resistance value. However, the present invention is not limited to this, and it is also possible to use other light-absorbing materials to obtain a required specific resistance value.

Next, a more specific configuration example of the present invention will be described.

FIG. 6 is a connection diagram of an equivalent circuit of a display matrix portion of a liquid crystal display device according to the present invention and its peripheral circuits.

In the figure, AR indicates a matrix array in which a plurality of pixels are two-dimensionally arranged, X indicates a video signal line DL, and suffixes G, B, and R respectively correspond to green, blue, and red pixels. .

DTM denotes a drain terminal, GTM denotes a gate terminal, Y denotes a scanning signal line GL, and suffixes 1, 2, 2,
.., End follow the order of the scanning timing. The scanning signal line Y (subscript omitted) is connected to the vertical scanning circuit V.

The video signal line X (subscript omitted) is connected to a video signal drive circuit H arranged on one of the long sides of the display panel, and the terminal is drawn out to only one side of the liquid crystal display panel like the scanning signal line Y. ing.

The SUP uses a TFT for transmitting information for a CRT (cathode ray tube) from a power supply circuit for obtaining a stabilized voltage source divided from one voltage source or a host (upper processing unit).
Also includes a circuit for converting the information into information for a liquid crystal display device.

FIG. 7 is an exploded perspective view for explaining one configuration example of a liquid crystal display device according to the present invention. The liquid crystal display device (hereinafter, a liquid crystal display panel, a circuit board, a backlight, and other components are integrated). Module: MDL)
This is to explain the specific structure of the above.

In the figure, SHD is a shield case (also referred to as a metal frame) made of a metal plate, WD is a display window, INS1 to 3 are insulating sheets, PCB1 to 3 are circuit boards (PCB1 is a drain side circuit board: video signal). Line driving circuit board, PCB2 is gate side circuit board, PCB3 is interface circuit board), JN1-3 are circuit boards PC
Joiner for electrically connecting B1 to B1, TCP1,
TCP2 is a tape carrier package, PNL is a liquid crystal display panel, GC is a rubber cushion, ILS is a light shielding spacer, PRS is a prism sheet, SPS is a diffusion sheet, G
LB is a light guide plate, RFS is a reflection sheet, MCA is a lower case (mold frame) formed by integral molding,
MO is an opening of the MCA, LP is a fluorescent tube, LPC is a lamp cable, GB is a rubber bush supporting the fluorescent tube LP, B
AT denotes a double-sided adhesive tape, BL denotes a backlight made of a fluorescent tube, a light guide plate, or the like, and a liquid crystal display module MDL is assembled by stacking diffusion plate members in the arrangement shown in the drawing.

The liquid crystal display module MDL has two kinds of storage / holding members of a lower case MCA and a shield case SHD, and includes insulating sheets INS1 to 3 and circuit boards PCB1 to PCB1.
3. A metal shield case SHD in which a liquid crystal display panel PNL is stored and fixed, and a lower case MCA in which a backlight BL including a fluorescent tube LP, a light guide plate GLB, a prism sheet PRS, and the like are stored are combined.

An integrated circuit chip for driving each pixel of the liquid crystal display panel PNL is mounted on the video signal line driving circuit board PCB1, and the interface circuit board PC
The B3 includes an integrated circuit chip that receives a video signal from an external host, receives a control signal such as a timing signal, and a timing converter TCON that processes a timing to generate a clock signal.

The clock signal generated by the timing converter is integrated on the video signal line driving circuit board PCB1 via the clock signal line CLL laid on the interface circuit board PCB3 and the video signal line driving circuit board PCB1. Supplied to the circuit chip.

The interface circuit board PCB3 and the video signal line driving circuit board PCB1 are multilayer wiring boards, and the clock signal line CLL is connected to the interface circuit board PCB3 and the video signal line driving circuit board PC
It is formed as an inner wiring of B1.

The liquid crystal display panel PNL has a drain-side circuit board PCB1, a gate-side circuit board PCB2 and an interface circuit board PC for driving TFTs.
B3 is connected by the tape carrier packages TCP1 and TCP2, and the circuit boards are connected by the joiners JN1, JN2, JN3.

The liquid crystal display panel PNL is an in-plane switching mode liquid crystal display device according to the present invention described above. The specific resistance of the BM formed on the color filter substrate is increased, and the electric field formed between the pixel electrode and the common electrode is increased. A pattern is formed substantially parallel to the interface of the liquid crystal layer.

FIG. 8 is an external view of a personal computer for explaining an example of an information processing apparatus equipped with the liquid crystal display device according to the present invention. The inverter power supply and CPU are a host-side central processing unit.

As shown in the figure, a personal computer on which the liquid crystal display device according to the present invention is mounted is a video signal line driving circuit board (horizontal driving circuit board: drain side circuit board) PC
By arranging B1 only at the upper part of the screen, a space below the display unit (keyboard side) can be given a margin, and the installation space (hinge space) of the hinge connecting the keyboard unit and the display unit can be reduced. Therefore, the outer size of the display unit can be reduced, and the size of the entire personal computer can be reduced.

[0085]

As described above, according to the present invention,
Since the electric field generated by the selection voltage in the so-called lateral electric field type thin film transistor type liquid crystal display device does not enter the black mask, the generation of domains due to the disturbance of the electric field pattern described above is eliminated, and a high quality color liquid crystal display device without color unevenness is provided. Can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of one pixel illustrating an operation of a liquid crystal display device to which the present invention is applied.

FIG. 2 is an explanatory diagram of a structural example of a TFT substrate constituting one embodiment of the liquid crystal display device according to the present invention.

FIG. 3 is an explanatory diagram of a structural example of a color filter substrate constituting one embodiment of the liquid crystal display device according to the present invention.

FIG. 4 is a schematic view of an electric field pattern in a cross section of one pixel constituting one embodiment of the liquid crystal display device according to the present invention.

FIG. 5 is an explanatory diagram of the relationship between the specific resistance of the BM and the drive voltage when the specific resistance of the BM is changed in each embodiment of the present invention.

FIG. 6 is a connection diagram of an equivalent circuit of a display matrix unit of a liquid crystal display device according to the present invention and peripheral circuits thereof.

FIG. 7 is an exploded perspective view illustrating one configuration example of a liquid crystal display device according to the present invention.

FIG. 8 is an external view of a personal computer illustrating an example of an information processing device equipped with a liquid crystal display device according to the present invention.

FIG. 9 is a schematic cross-sectional view illustrating a configuration and a lighting operation of one pixel included in a liquid crystal display device of an in-plane switching mode.

FIG. 10 is a schematic diagram of one pixel of a lateral electric field type liquid crystal display device in which two comb-shaped common electrodes are arranged in one pixel.

11 is an explanatory diagram of a difference between the transmittance between the two comb-shaped common electrodes shown in FIG. 10 and the transmittance between each comb-shaped common electrode and an adjacent pixel electrode.

[Explanation of symbols]

 1, 1 'Transparent glass substrate (substrate) 2 Common electrode 6 Insulating film 10 Signal wiring 11 Pixel electrode 12 Protective film 13, 13' Polarizing plate 14, 14 'Polarizing axis of polarizing plate 15 Orientation direction of liquid crystal molecules 16 Electric field direction 17 Black mask (BM) 18 Color filter 19 Protective film (flattening film) 20, 20 'Alignment film 21 Liquid crystal (rod-like liquid crystal molecules).

Claims (9)

[Claims] 1. A pair of substrates, at least one of which is transparent; a black mask formed on one of the pair of substrates; and a liquid crystal composition having dielectric anisotropy sandwiched between the pair of substrates. In a thin film transistor type liquid crystal display device having a liquid crystal layer, a direction of an electric field applied to the liquid crystal layer is a direction substantially parallel to the substrate, and a specific resistance value of the black mask is 10 ⁸ Ω · cm or more. A thin film transistor type liquid crystal display device characterized by the above-mentioned. 2. An electrode group comprising: an electrode group formed on one of the pair of substrates; and an alignment film for aligning a molecular arrangement of the liquid crystal composition material in a predetermined direction. 2. A thin film transistor type liquid crystal display device according to claim 1, wherein said electrode arrangement structure forms an electric field mainly parallel to an interface between said alignment film and said liquid crystal layer. 3. The color filter according to claim 1, wherein the black mask is arranged between at least two or more types of color filters having different colors for color display formed on one of the pair of substrates. The thin film transistor type liquid crystal display device as described in the above. 4. The thin film transistor type liquid crystal display device according to claim 2, wherein a plurality of pixels arranged in a matrix are formed on said one substrate, and said black mask is formed on the other substrate. . 5. The thin film transistor type liquid crystal display device according to claim 2, wherein said electrode group comprises at least a common electrode and a pixel electrode. 6. The thin film transistor type liquid crystal display device according to claim 5, further comprising driving means for applying a driving voltage to said electrode group. 7. The thin film transistor type liquid crystal display device according to claim 1, wherein a resist in which graphite is dispersed is used as a material of said black mask. 8. A personal computer on which the thin film transistor type liquid crystal display device according to claim 1 is mounted. 9. A pair of substrates, at least one of which is transparent, at least two or more kinds of color filters having different colors for color display formed on one of the pair of substrates, and interposed between the color filters. A black mask, an electrode group formed on the other of the pair of substrates, a liquid crystal layer made of a liquid crystal composition having dielectric anisotropy sandwiched between the pair of substrates, and the liquid crystal composition A thin film transistor comprising: an orientation control film for orienting the molecular arrangement of the substrate in a predetermined direction; a polarizing unit laminated on at least one of the pair of substrates; and a driving unit for applying a driving voltage to the electrode group. In the liquid crystal display device, the electrode group has an electrode arrangement structure arranged so as to form an electric field mainly parallel to an interface between the alignment control film and the liquid crystal layer, Resistivity of the black mask 10 ^M Ω · cm or more,
Here, M is an integer, and a relationship satisfying M> 8 is satisfied.