JP2001166318A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of display defects such as the unevenness of luminance in a display screen by eliminating the variation of a cell gap. SOLUTION: A liquid crystal display device provided with a first insulating substrate having one electrodes group formed thereon for selecting pixels, a second insulating substrate having at least two kinds of color filters having colors different from one another for color display, black matrices between the color filters and the other electrodes group for selecting pixels, which are formed thereon, a liquid crystal panel having a liquid crystal layer having dielectric anisotropy and sealed between the first and the second substrates opposed to each other and an alignment controlling layer for arranging the molecular arrangement of the liquid crystal layer in a prescribed direction and a driving means for forming an electric field between the one electrodes group and the other electrodes group by applying a driving voltage for selecting pixels onto each electrodes group of the first and the second substrates, is characterized in that one or more cylindrical spacers formed by coating polymer beads with a resin material and having a height nearly equal to the desired height of the liquid crystal layer are fixedly provided in the gap between the first and the second insulating substrates opposed to each other of the liquid crystal panel constituting the liquid crystal display device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device having a novel structure for maintaining a constant gap between a pair of insulating substrates enclosing a liquid crystal layer.

[0002]

2. Description of the Related Art A liquid crystal display device has been widely used as a display device capable of displaying a high-definition color image for a notebook computer or a computer monitor.

In this type of liquid crystal display device, a layer of a liquid crystal composition (a liquid crystal composition) is basically formed in a gap between at least two insulating substrates made of first and second insulating substrates made of transparent glass or the like. Hereinafter, it is simply referred to as a liquid crystal or a liquid crystal layer.)
A type in which a predetermined pixel is turned on and off by selectively applying a voltage to a so-called liquid crystal panel sandwiching the above and a so-called liquid crystal panel and various wirings and electrodes for forming a pixel formed on the opposed inner surface of the insulating substrate of the liquid crystal panel (simple) Matrix type liquid crystal display device) and a type in which the above-mentioned various electrodes and switching elements for pixel selection are formed, and a selected pixel is turned on and off by selecting the switching element (active matrix type liquid crystal display device). Is done.

An active matrix type liquid crystal display device is
Various devices have been proposed as the switching device, but a device using a thin film transistor (TFT) is typical at present. A liquid crystal display device using a thin film transistor has been widely used as a display terminal monitor of OA equipment because it is thin, lightweight, and has a high image quality comparable to a cathode ray tube. Has also been put to practical use.

[0005] The display methods of this liquid crystal display device are roughly classified into the following two types based on the difference in the method of driving the liquid crystal. Part 1
First, a transparent electrode (pixel electrode and common electrode) is formed on each of the two insulating substrates, one of the transparent electrodes (pixel electrode) is selected by a thin film transistor, a voltage is applied, and light incident on the liquid crystal layer is applied. Is selectively modulated and transmitted (so-called vertical electric field method: TN method).

The other is operated by an electric field formed substantially parallel to the surface of the insulating substrate between two electrodes (pixel electrode and counter electrode) formed on the same insulating substrate, and a liquid crystal is formed through a gap between the two electrodes. This is a method of selectively modulating and displaying light incident on the layer (so-called lateral electric field method: IPS method). The liquid crystal display device of this type has a feature that the viewing angle is extremely wide, and an extremely high quality image display can be obtained as an active matrix liquid crystal display device. Regarding the features of this method, see, for example, Japanese Patent Application Publication
7, Japanese Patent Publication No. 63-21907,
It is described in documents such as Japanese Patent No. 160878.

In such a liquid crystal display device, a spherical spacer such as a polymer bead is dispersed in the gap between the two insulating substrates or one of the insulating substrates in order to keep the gap between the insulating substrates constituting the liquid crystal panel at a desired value. A columnar spacer (columnar spacer) fixedly formed on the substrate is provided.

When a spherical spacer such as a polymer bead is disposed in a pixel portion of a display area, the spherical spacer itself is basically a transparent material, or the alignment disorder of liquid crystal molecules near the spherical spacer causes a so-called light. Since leakage and domains occur, it is desirable to dispose a spherical spacer in a non-pixel portion (immediately below or near a black matrix). Japanese Patent Application Laid-Open No. H11-202345 discloses such a conventional technique.

Further, the prior arts in which columnar spacers are fixedly formed on the inner surface of an insulating substrate are disclosed in, for example, JP-A-9-73088 and JP-A-7-3252.
No. 98 publication.

[0010]

In the liquid crystal display device having the columnar spacers formed therein, when the liquid crystal display device is used in an upright state, if the temperature of the liquid crystal panel rises, it is considered that gaps are formed below the liquid crystal panel. Display failure may occur. The reason for this is that the viscosity of the liquid crystal layer decreases as the temperature of the liquid crystal panel rises, and the liquid crystal composition concentrates on the lower part of the liquid crystal panel due to its own weight, increasing the distance between the insulating substrates or increasing the temperature of the liquid crystal. It is conceivable that the columnar spacer is peeled off from the other insulating substrate due to the expansion of.

FIG. 13 is a sectional view of an essential part for explaining a structural example of a conventional liquid crystal panel using a columnar spacer and peeling of the columnar spacer. Although FIG. 13 illustrates an IPS mode liquid crystal panel as an example, the same applies to liquid crystal panels of other modes.

In FIG. 13, the liquid crystal panel includes a thin film transistor (not shown), a pixel electrode PX, a counter electrode CT,
A first insulating substrate SUB1 on which various wirings such as the drain lines DL and the like and an orientation control layer (also referred to as an orientation film) are formed, and a first filter on which a color filter FIL, a black matrix BM, an overcoat layer OC, and an orientation control layer ORI2 are formed. The two insulating substrates SUB2 are bonded to each other so as to face each other, and a liquid crystal layer LC is sealed in a gap between the substrates. AOF is an insulating film, GI is a gate insulating film, PSV1 and PSV2 are passivation films, and POL1 and POL2 are polarizing plates.

The second insulating substrate SUB2 has a columnar spacer SOC formed by a resin photolithography technique or the like. The first insulating substrate SUB1 and the liquid crystal layer L
After bonding through C, a required gap is formed by pressing. In this gap setting, the columnar spacer SO
The top of C is pressed against the inner surface (orientation control film ORI1) of the first insulating substrate SUB1 to determine the height of the columnar spacer SOC so as to define a required gap.

When the temperature rises to a certain degree during use of the liquid crystal panel, the columnar spacer SOC is brought out of engagement with the first insulating substrate SUB1 due to local concentration due to the weight of the liquid crystal or expansion of the liquid crystal itself. Peeling occurs and the cell gap regulating ability is lost, and the thickness of the liquid crystal layer, the so-called cell gap, increases by B. Thereby, the dielectric anisotropy Δ
nd changes, causing display unevenness.

When the temperature of the liquid crystal panel decreases, bubbles may be generated due to the contraction of the liquid crystal. Such bubbles do not disappear even when the temperature returns to the steady temperature, and cause display defects (uneven brightness, point defects, etc.).

Further, in the case where the polymer beads are used as spacers, the polymer beads move by an external impact,
There is a problem that the polymer beads are locally concentrated to reduce the gap regulating ability, uneven distribution of light leakage occurs, and the liquid crystal is contaminated by the polymer beads being in contact with the liquid crystal.

An object of the present invention is to solve the above-mentioned problems in the prior art and to provide a high quality and high reliability liquid crystal display device by suppressing display defects such as uneven brightness in a display screen.

[0018]

In order to achieve the above object, the present invention provides a liquid crystal display device having a height substantially equal to the thickness of a liquid crystal layer formed between a pair of substrates constituting a liquid crystal panel, or It is characterized in that particles or particles having a stacking height substantially equal to the thickness of the liquid crystal layer are coated with a resin to form columnar spacers.

Typical configurations of the present invention are as described in the following (1) to (5). That is, (1) a first insulating substrate on which the other electrode group for pixel selection is formed, at least two or more types of color filters having different colors for color display, and a black matrix and a pixel between each color filter. A second insulating substrate on which one electrode group for selection is formed; a liquid crystal layer having a dielectric anisotropy sealed in a gap between the first and second substrates; A liquid crystal panel having an alignment control layer for arranging in one direction, and applying a driving voltage for selecting a pixel to each of the electrode groups provided on the first and second insulating substrates, so as to apply the one electrode group to the other electrode group. A driving means for forming an electric field between the electrode groups, wherein at least one polymer having a height substantially equal to a desired thickness of the liquid crystal layer is provided in a gap between the first and second insulating substrates. Columns with beads coated with resin A spacer was fixedly provided on one of the first and second insulating substrates.

(2) A first substrate having a switching element for selecting a pixel and an electrode group including a signal wiring and a common wiring for supplying a pixel selection voltage to the switching element, and disposed opposite to the first substrate A second insulating substrate formed with at least two or more types of color filters having different colors for color display and a black matrix interposed between the color filters, and an opposing gap between the first and second insulating substrates A liquid crystal layer having dielectric anisotropy enclosed in
A liquid crystal panel having an alignment control layer for arranging the molecular arrangement of the liquid crystal layer in a predetermined direction at an interface between the first and second insulating substrates in contact with the liquid crystal layer; and the electrode of the first insulating substrate. A driving unit for applying a driving voltage for driving the switching element to select a pixel to form an electric field substantially parallel to a surface of the first insulating substrate; A columnar spacer in which at least one polymer bead is coated with a resin material at a height substantially equal to a desired thickness of the liquid crystal layer in one of the first and second insulating substrates; And fixedly provided.

(3) The columnar spacer is composed of one polymer bead having a height in a direction orthogonal to the surfaces of the first and second insulating substrates substantially equal to the gap between the first and second insulating substrates. did.

(4) The plurality of polymer beads having a stacking height in a direction orthogonal to the surfaces of the first and second insulating substrates substantially equal to the gap between the first and second insulating substrates. Was configured.

(5) The spacer is provided immediately below the black matrix.

After the formation of the black matrix of the second insulating substrate or the formation of the electrodes, the columnar spacer is coated with a resin material (resist material) containing polymer beads, and is applied to a non-pixel region (non-pixel region) via a photomask. (Pixel portion) For example, exposure is performed so as to remain only at the intersection of the black matrix or directly above the black matrix, and development is performed to form a columnar spacer in which polymer beads are covered with a resin agent.

When the number of the polymer beads constituting each columnar spacer is one, the height of the polymer beads is set to be substantially equal to the thickness of the liquid crystal layer sealed between the insulating substrates, that is, the cell gap. Are formed into one columnar spacer, the stack height of the plurality of polymer beads is set to be substantially the same as the thickness of the liquid crystal layer.

As described above, since the cell gap is basically regulated by the polymer beads, the cell gap can be easily formed by pressing in the gap setting, and the expansion and contraction due to the temperature can be easily followed. It is difficult to generate gap unevenness and low-temperature bubbles.

Further, since the polymer beads do not come into contact with the liquid crystal, the contamination of the liquid crystal by the polymer beads can be prevented.

Furthermore, even when the columnar spacers are applied to the pixel portions due to a shift of the exposure mask, the disordering of the liquid crystal alignment and light leakage near the polymer beads occur because the polymer beads are covered with the resin material. And display quality is not degraded.

Since the polymer beads are fixed with the resin material, the polymer beads do not move in response to an external impact.

The present invention is not limited to the above configuration and the configuration of the embodiment described later, and various modifications can be made without departing from the technical idea of the present invention.

[0031]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a schematic sectional view of a main part of a liquid crystal panel for explaining a first embodiment of a liquid crystal display device according to the present invention, and FIG. 2 is a schematic plan view of the same main part. 1 and 2 show an embodiment in which the present invention is applied to a simple matrix type or TN type liquid crystal display device.

The first insulating substrate SUB1 has a pixel electrode (one electrode in a simple matrix system) on the inner surface of a glass substrate.
PT and an orientation film ORI1. Note that the first insulating substrate SUB1 is referred to as a thin film transistor substrate (TFT substrate) in the TN mode, and thin film transistors, other wirings or electrodes, and various functional films are formed.
The illustration is omitted.

The second insulating substrate SUB2 is a so-called color filter substrate, and a plurality of (generally three) color filters FIL (R) and FIL (G) partitioned by a black matrix BM on the inner surface of a glass substrate. , FIL (B) are arranged in a mosaic pattern or the like. An overcoat layer OC and a common electrode (the other electrode in a simple matrix system) CT are formed thereon.

A columnar spacer in which one polymer bead BZ is covered with a resin material REG is formed on the overcoat layer OC at the intersection of the black matrix BM. Since the overcoat layer OC is also a resin material, both are firmly bonded. After the formation of the columnar spacer, an orientation film ORI2 is applied. FIG. 2 shows a state before the overcoat layer OC is formed.

In this embodiment, the thickness of the liquid crystal layer LC sealed in the opposing gap between the first insulating substrate SUB1 and the second insulating substrate SUB2 is basically the thickness of one polymer bead BZ constituting the columnar spacer. It is regulated by the height (the size in the direction perpendicular to the substrate surface).

In the gap setting step, the two insulating substrates bonded to each other are pressed so that the polymer beads BZ are aligned with the alignment film OR.
A predetermined cell gap is set in a state where it is slightly sunk into I1 and ORI2. Therefore, the cell gap is the same as the conventional one using only the polymer beads, and the columnar spacer easily follows expansion and contraction due to temperature, and it is difficult to generate gap unevenness and low-temperature bubbles of liquid crystal.

Further, the polymer beads are covered with the resin material REG and also covered with the alignment film ORI2, so that they do not come into contact with the liquid crystal. Since the polymer beads BZ are isolated from the liquid crystal, the polymer beads BZ are separated from the liquid crystal. Contamination can be prevented.

Further, even when the columnar spacer is applied to the pixel portion due to a shift of the exposure mask or the like, disturbance of liquid crystal alignment and light leakage near the polymer beads do not occur, and display quality is not deteriorated.

Since the polymer beads are fixed by the resin material, the polymer beads do not move in response to an external impact.

FIG. 3 is a schematic sectional view of a main part of a liquid crystal panel for explaining a second embodiment of the liquid crystal display device according to the present invention, and FIG. 4 is a schematic plan view of the same main part. 3 and 4 also show an embodiment in which the present invention is applied to a simple matrix type or TN type liquid crystal display device.

As in the first embodiment, the first insulating substrate SU
B1 has a pixel electrode (one electrode in a simple matrix system) PT and an alignment film ORI1 on the inner surface of the glass substrate. Note that the first insulating substrate SUB1 is referred to as a thin film transistor substrate (TFT substrate) in the TN mode, in which thin film transistors, other wirings or electrodes, and various functional films are formed, but are not shown.

The second insulating substrate SUB2 is a so-called color filter substrate, and a plurality of (generally three) color filters FIL (R), FIL (G) partitioned on the inner surface of a glass substrate by a black matrix BM. , FIL (B) are formed in a mosaic shape. On top of that, an overcoat layer OC and a common electrode (the other electrode in the simple matrix system)
The CT has been formed.

A columnar spacer in which a plurality of polymer beads BZ are laminated and covered with a resin material REG is formed on the overcoat layer OC at the intersection of the black matrix BM. Since the overcoat layer OC is also a resin material, both are firmly bonded. After the formation of the columnar spacer, an orientation film ORI2 is applied. FIG. 4 shows a state in which the overcoat layer OC has been removed.

Also in this embodiment, the thickness of the liquid crystal layer LC sealed in the opposing gap between the first insulating substrate SUB1 and the second insulating substrate SUB2 is determined by the lamination height of the plurality of polymer beads BZ constituting the columnar spacer ( (The size in the direction perpendicular to the substrate surface).

In the gap setting step, both insulating substrates are pressed to laminate the polymer beads BZ on the alignment film ORI.
1, a predetermined cell gap is set in a state where the cell gap is slightly immersed in ORI2. Therefore, the columnar spacer easily follows expansion and contraction due to temperature, and is unlikely to cause gap unevenness and low-temperature bubbles of liquid crystal.

The plurality of polymer beads BZ are made of a resin material REG.
And is also covered with the orientation film ORI2, so that it does not come into contact with the liquid crystal, and the polymer beads BZ
Is isolated from the liquid crystal, so that contamination of the liquid crystal by the polymer beads can be prevented.

Further, even when the columnar spacer is applied to the pixel portion due to a shift of the exposure mask or the like, the liquid crystal alignment in the vicinity of the polymer beads and light leakage do not occur, and the display quality is not deteriorated. This is the same as the embodiment.

Also in this embodiment, since the polymer beads are fixed by the resin material, the polymer beads do not move in response to an external impact.

FIG. 5 is a schematic cross-sectional view of a principal part of a liquid crystal panel illustrating a third embodiment and a fourth embodiment of the liquid crystal display device according to the present invention. FIG. 6 is a cross section taken along line 1-1 'of FIG. FIG. 3 and 4 show an embodiment in which the present invention is applied to an IPS liquid crystal panel. FIG. 5 is a plan view of the first insulating substrate. In the configuration of the second insulating substrate, only the black matrix BM is indicated by a boundary line.

As shown in FIG. 5, the liquid crystal panel of the IPS mode has a gate line GL and a gate electrode GT, a drain line DL and a drain electrode SD2, a counter voltage line CL and a counter electrode on the inner surface of a first insulating substrate SUB1. Electrode CT,
The pixel electrode PX and the source electrode SD1 are formed.

The thin film transistor TFT has a gate electrode G
T (extending from the gate line to the thin film transistor TFT), a drain electrode SD2, a source electrode SD1, and a semiconductor layer AS, and the source electrode SD1 is a pixel electrode PX (actually, a thin film transistor TF
In the vicinity of T, the source electrode SD1 and the pixel electrode PX are connected by a through hole). Note that a storage capacitor Cstg is formed at a portion where the part of the pixel electrode PX and the counter voltage line CL overlap.

One pixel is located in the opening of the black matrix BM, and the thin film transistor TFT is arranged on the gate line.

As shown in detail in FIG.
L is composed of a two-layer wiring of a conductive layer d1 and a conductive layer d2,
The counter voltage line CL and the counter electrode CT have a conductive layer g1 covered with an insulating layer AOF, and the pixel electrode PX is formed of a single conductive layer g2. Note that POL1 and POL2
Indicates a polarizing plate.

The columnar spacers of this embodiment are denoted by SOC, and in the third embodiment, as shown on the right side of FIG.
One polymer bead BZ covered with a resin material REG is fixed on the drain line DL. This cross section corresponds to FIG.

According to the present embodiment, the cell gap becomes the same as the conventional cell gap using only the polymer beads.
Further, the columnar spacer easily follows expansion and contraction due to temperature, and is unlikely to cause gap unevenness and low-temperature bubbles of liquid crystal.

Further, the polymer beads are covered with the resin material REG and are also covered with the alignment film ORI2, so that they do not come into contact with the liquid crystal. Since the polymer beads BZ are isolated from the liquid crystal, the polymer beads BZ are separated from the liquid crystal. Contamination can be prevented.

Further, even when the columnar spacer is applied to the pixel portion due to a shift of the exposure mask or the like, disturbance of liquid crystal alignment or light leakage near the polymer beads does not occur, and the display quality is not degraded.

Since the polymer beads are fixed by the resin material, the polymer beads do not move in response to an external impact.

In the fourth embodiment of the present invention, as shown on the left side of FIG. 5, a plurality of polymer beads BZ covered with a resin material REG are fixed on a drain line DL and a counter voltage line CL. is there. FIG. 6 is a cross-sectional view of the present embodiment, in which a plurality of polymer beads BZ are covered with a resin material REG to form a columnar spacer SOC, immediately below a black matrix BM, and above a drain line DL and a counter voltage line CL. Are located in

Also in this embodiment, the cell gap is the same as the conventional one using only the polymer beads, and the columnar spacer easily follows expansion and contraction due to temperature, causing uneven gap and generation of low-temperature bubbles in the liquid crystal. Is unlikely to occur.

Since the polymer beads are covered with the resin material REG and also covered with the alignment film ORI2, they do not come into contact with the liquid crystal LC, so that the polymer beads BZ
Is isolated from the liquid crystal, so that contamination of the liquid crystal LC by the polymer beads BZ can be prevented.

Further, even when the columnar spacer SOC is applied to the pixel portion due to a shift of the exposure mask or the like, the liquid crystal alignment is not disturbed in the vicinity of the polymer beads and light leakage does not occur, and the display quality is not deteriorated.

Since the polymer beads are fixed by the resin material, the polymer beads do not move in response to an external impact.

If the columnar spacer SP is formed of a resin material of the same material as the overcoat layer, the columnar spacer SP can be firmly fixed. However, the present invention is not limited to this, and any resin material having good compatibility with the overcoat layer can be used. It can be planted at a predetermined position with a sufficient fixing force.

In each of the above embodiments, the columnar spacer S
Although P was formed on the color filter substrate (second substrate SUB2), the active matrix substrate (first substrate SU) was formed.
It may be formed on the B1) side.

The number and positions of the columnar spacers SP per pixel are not limited to those shown in the figure, and may be arranged in a staggered manner or randomly. Also, the columnar spacer SP
Although the planar shape of is a shape of an ellipse, other shapes such as a circle, a square, a rhombus, a bank, etc. may be used. Next, the outline of the manufacturing process of the liquid crystal display device according to the third or fourth embodiment of the present invention will be described.
Here, a method of forming the columnar spacer SOC simultaneously with the overcoat layer OC will be described.

First, a thin film transistor made of amorphous silicon AS is formed by repeating film formation and patterning on a glass substrate having a thickness of 0.7 mm or 1.1 mm as a first substrate SUB1 in the same manner as a known thin film transistor forming process. An electrode group including a TFT, a storage capacitor Cstg and a pixel electrode PX, a source electrode SD1, and a counter electrode CT is formed. Furthermore, a plurality of drain lines (video signal lines) DL for applying a predetermined voltage to the electrode group via the thin film transistor TFT, a drain electrode SD2, a counter voltage line CL, and a plurality of gate line lines for controlling conduction of the thin film transistor TFT. The GL and the gate electrode GT are formed in a grid pattern to form a TFT substrate.

The thin film transistor TFT, each electrode group and each wiring are covered with an insulating film GI and a protective film PSV. Thereafter, an alignment film material is applied and baked, and a liquid crystal alignment control ability is imparted by a rubbing process or a photo alignment process to obtain an alignment control layer ORI1.

The other substrate SUB2 has a thickness of 0.1 mm.
A black matrix BM is formed by applying a photosensitive black resist on a 7 mm or 1.1 mm glass substrate and exposing, developing, and firing using a photomask having a predetermined pattern.

Next, using the photosensitive red, green, and blue resin resists, the same exposure, development, and baking steps as described above are repeated to form a color filter layer FIL (a red colored layer FIL (R)). , Green colored layer FIL (G), blue colored layer F
IL (B)).

The columnar spacer SOC is a polymer bead B
An ultraviolet curable resin mixed with Z is used. A UV curable resin containing polymer beads is applied on the entire surface of the color filter layer, and UV light is irradiated to a position where the columnar spacer SOC is to be formed through a photomask having a desired pattern.
develop.

At this time, the development is stopped during a time period in which the non-photosensitive portion remains as the overcoat layer OC, and baking is performed, whereby the black matrix BM and the color filter layer F
Overcoat layer OC covering IL and columnar spacer S
Form P.

Thereafter, an alignment film material is applied to a color filter substrate and baked to obtain an alignment film ORI having a liquid crystal alignment control ability.
Form 2

As a method of forming the columnar spacers SOC after the formation of the overcoat layer OC, after forming the black matrix BM and the color filter FIL, apply a transparent ultraviolet-curing resin resist and bake to cover the entire surface. Obtaining a columnar spacer SP by coating with a coat layer OC, applying a transparent ultraviolet curable resin mixed with polymer beads again, irradiating ultraviolet rays through a photomask having a desired pattern, and developing and firing. Can be.

Thereafter, an alignment film material is applied to a color filter substrate and baked to provide an alignment film ORI having a liquid crystal alignment control ability.
Form 2

Note that the columnar spacer SP is formed on the TFT substrate (S
In the case of forming on the UB1) side, a transparent ultraviolet curable resin resist mixed with polymer beads is applied on the insulating film PSV of the TFT substrate, and irradiated with ultraviolet rays through a photomask having a desired pattern, The columnar spacer SP is also obtained by developing and baking.

The first insulating substrate SUB1 and the second insulating substrate SUB2 manufactured as described above are opposed to each other with a gap therebetween, and the peripheral portions thereof are fixed with an adhesive except for a liquid crystal sealing port. The liquid crystal composition is sealed in the opening, and the liquid crystal filling opening is sealed with a sealing material.

Thereafter, the distance between the two substrates is regulated by the column spacer SOC by pressing to obtain a liquid crystal display device having a predetermined cell gap.

Next, the driving means of the liquid crystal display device to which the present invention is applied and specific product examples will be described.

FIG. 7 is an explanatory diagram of a configuration of a liquid crystal display device to which the present invention is applied and a drive system. This liquid crystal display device uses the active matrix type liquid crystal panel of the above embodiment.

A data line (drain line or video signal line) drive circuit (IC chip), ie, a drain driver DDR, and a scanning line (gate line) drive circuit (IC chip), ie, a gate driver GDR are provided around the liquid crystal panel PNL. Display data and a clock signal for image display to the drain driver DDR and the gate driver GDR;
A controller CRL, which is a display control unit for supplying a gradation voltage and the like, and a power supply unit PWU are provided.

Display data from an external signal source such as a computer, a personal computer, and a television receiver circuit and a control signal clock, a display timing signal, and a synchronization signal are transmitted to the controller C.
Input to RL. The controller includes a gradation reference voltage generator, a timing controller TCON, and the like, and converts external display data into data in a format suitable for display on the liquid crystal panel PNL.

Display data and a clock signal for the gate driver GDR and the drain driver DDR are supplied as shown. The carry output of the previous stage of the drain driver DDR is directly supplied to the carry input of the next stage drain driver.

FIG. 8 is a block diagram showing a schematic configuration of each driver of the liquid crystal panel and a signal flow. The drain driver DDR includes a data latch unit for display data such as a video (image) signal and an output voltage generation circuit. Further, a gradation reference voltage generation unit HTV, a multiplexer MPX, a common voltage generation unit CVD, a common driver CDD, a level shift circuit LST, a gate-on voltage generation unit GOV, a gate-off voltage generation unit GFD, and a DC-DC converter D
/ D is provided in the power supply unit PWU of FIG.

FIG. 9 is a timing chart showing display data input from the signal source (main body) to the controller and signals output from the controller to the drain driver and the gate driver. The controller CRL controls signals (clock signals, display timing signals,
(A synchronization signal), a clock D1 (CL1) and a shift clock D1 as control signals to the drain driver DDR.
2 (CL2) and display data, and at the same time, a frame start instruction signal FLM, a clock G (CL3) and display data as control signals to the gate driver GDR.

In a system using a low-voltage differential signal (LVDS signal) for transmission of display data from a signal source, the LVDS signal from the signal source is applied to an LVDS mounted on a board (interface board) on which the controller is mounted.
The signal is converted to the original signal by the receiving circuit, and then the gate driver GD
R and the drain driver DDR.

As apparent from FIG. 9, the shift clock signal D2 (CL2) of the drain driver is the same as the frequency of the clock signal (DCLK) and display data input from the main body computer or the like. High frequency of 40 MHz (megahertz).

FIG. 10 is an exploded perspective view for explaining the whole structure of the liquid crystal display device according to the present invention. : MDL).

SHD is a shield case (also called a metal frame) made of a metal plate, WD is a display window, INS1
3 to 3 are insulating sheets, PCBs 1 to 3 are circuit boards constituting driving means (PCB 1 is a drain side circuit board: a circuit board for driving a video signal line, PCB 2 is a gate side circuit board, PCB
3 is an interface circuit board), JN1 to 3 are joiners for electrically connecting the circuit boards PCB1 to PCB3, TC
P1 and TCP2 are tape carrier packages, PNL is a liquid crystal panel, GC is a rubber cushion, ILS is a light shielding spacer, PRS is a prism sheet, SPS is a diffusion sheet,
GLB is a light guide plate, RFS is a reflection sheet, MCA is a lower case (mold frame) formed by integral molding, MO is an MCA opening, LP is a fluorescent tube, LPC is a lamp cable, and GB supports a fluorescent tube LP. A rubber bush, BAT is a double-sided adhesive tape, BL is 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.

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 INS3 and circuit boards PCB1 to PCB1.
3. A metal shield case SHD in which a liquid crystal 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 panel PNL is mounted on the video signal line driving circuit board PCB1, and an interface circuit board PCB3
Is mounted with 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 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. The supply to the circuit chip is as described above.

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 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 panel PNL has a drain-side circuit board PCB1, a gate-side circuit board PCB2, and an interface circuit board PCB3 for driving TFTs.
Are connected by tape carrier packages TCP1 and TCP2, and the circuit boards are connected by joiners JN1, JN2, JN3. The liquid crystal panel PNL is the active matrix type liquid crystal display device according to the present invention described above, and includes the columnar spacer containing particles and the polymer beads described in the above embodiment in order to maintain the distance between the two substrates at a predetermined value. ing.

A glass-on-chip (GOC) system (also referred to as an FCA system) in which each drive circuit (drain driver, gate driver) is directly mounted on one substrate of a liquid crystal panel, generally, around the substrate SUB1 is adopted. However, the present invention can be similarly applied to such a case.

The liquid crystal panel PNL is the active matrix type liquid crystal display device according to the present invention described above, and includes the columnar spacer containing the polymer beads described in the above embodiment in order to maintain the distance between the two substrates at a predetermined value. ing.

FIG. 11 is a perspective view of a notebook computer as an example of an electronic apparatus on which the liquid crystal display device according to the present invention is mounted. The notebook computer (portable personal computer) includes a keyboard unit (main body unit) and a display unit connected to the keyboard unit by a hinge. Keyboard and host (host computer), CP
U and other signal generation functions, and the display unit has a liquid crystal panel P
NL, and drive circuit boards PCB1 and PCB
2, PCB3 with control chip TCON,
In addition, an inverter power supply board serving as a backlight power supply is mounted.

The liquid crystal display module described with reference to FIG. 11 in which the liquid crystal display panel PNL, the various circuit boards PCB1, PCB2, PCB3, the inverter power supply board, and the backlight are integrated is mounted.

FIG. 12 is a front view of a display monitor as another example of the electronic apparatus on which the liquid crystal display device according to the present invention is mounted. The display monitor includes a display unit and a stand unit, and the liquid crystal display device having the liquid crystal panel PNL according to the present invention is mounted on the display unit. In this type of relatively large-sized monitor, a so-called sidelight-type backlight of the type described with reference to FIG. 10 is used as a light source device for illuminating the liquid crystal panel. In some cases, a direct backlight is used.

A host computer or a television receiving circuit may be built in the stand of such a display monitor.

As described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the technical idea of the present invention.

It is needless to say that the present invention is not limited to an active matrix type liquid crystal display device, but can be similarly applied to a simple matrix type liquid crystal display device.

[0104]

As described above, according to the present invention,
Because it is a spacer mainly composed of polymer beads that are more likely to compressively deform than a resin material, it is easy to follow the temperature change of the liquid crystal panel, and the occurrence of cell gap unevenness when the temperature of the liquid crystal panel increases and the liquid crystal expands, The generation of air bubbles when shrinking at low temperatures is suppressed, and the polymer beads are covered with a resin material, so they have excellent impact resistance, and the polymer beads do not come into direct contact with the liquid crystal layer. The contamination of the liquid crystal by the beads and the display failure due to the poor liquid crystal alignment near the polymer beads are avoided, and a high-quality and highly reliable liquid crystal display device can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a main part of a liquid crystal panel for explaining a first embodiment of a liquid crystal display device according to the present invention. It is a principal part schematic plan view.

FIG. 2 is a schematic plan view of a main part of a liquid crystal panel for explaining a first embodiment of the liquid crystal display device according to the present invention.

FIG. 3 is a schematic sectional view of a main part of a liquid crystal panel for explaining a second embodiment of the liquid crystal display device according to the present invention.

FIG. 4 is a schematic plan view of a main part of a liquid crystal panel for explaining a second embodiment of the liquid crystal display device according to the present invention.

FIG. 5 is a schematic cross-sectional view of a main part of a liquid crystal panel explaining a third embodiment and a fourth embodiment of the liquid crystal display device according to the present invention.

6 is a sectional view taken along line 1-1 'of FIG.

FIG. 7 is an explanatory diagram of a configuration of a liquid crystal display device to which the present invention is applied and a driving system.

FIG. 8 is a block diagram showing a schematic configuration of each driver of the liquid crystal panel and a signal flow.

FIG. 9 is a timing chart showing display data input from a signal source (body) to a controller and signals output from the controller to a drain driver and a gate driver.

FIG. 10 is an exploded perspective view illustrating the overall configuration of the liquid crystal display device according to the present invention.

FIG. 11 is a perspective view of a notebook computer as an example of an electronic apparatus on which the liquid crystal display device according to the present invention is mounted.

FIG. 12 is a front view of a display monitor as another example of the electronic apparatus on which the liquid crystal display device according to the present invention is mounted.

FIG. 13 is a sectional view of an essential part for explaining an example of the structure of a conventional liquid crystal panel using a columnar spacer and peeling of the columnar spacer.

[Explanation of symbols]

 DL Drain line (video signal line) SD1 Source electrode SD2 electrode CL Counter voltage signal line CT Counter electrode PX Pixel electrode Cstg Storage capacitance GL Gate line (scanning signal line) GT Same gate electrode as scanning electrode BM Black matrix TFT Thin film transistor SOC Columnar Spacer. BZ polymer beads REG resin material ORI1, ORI2 alignment film OC overcoat layer FIL color filter AOF insulating film LC liquid crystal layer GI gate insulating film PSV passivation layer (protective film) POL1, POL2 Polarizing plate SUB1, SUB2 insulating substrate.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H089 LA07 LA09 LA16 NA15 QA15 RA05 TA04 TA05 TA09 TA12 TA13 TA18 TA20 5C094 AA03 AA31 BA03 BA44 CA19 DA12 EA04 EC03 HA08

Claims (5)

[Claims] A first insulating substrate on which the other electrode group for pixel selection is formed; at least two or more types of color filters having different colors for color display; and a black matrix and a pixel between each color filter. A second insulating substrate on which one electrode group for selection is formed;
A liquid crystal panel having a liquid crystal layer having a dielectric anisotropy sealed in an opposing gap between the substrates and an alignment control layer for arranging the molecular arrangement of the liquid crystal layer in a predetermined direction; A driving unit for applying a driving voltage for selecting a pixel to each electrode group provided on the substrate to form an electric field between the one electrode group and the other electrode group; A columnar spacer in which at least one polymer bead is coated with a resin material at a height substantially equal to a desired thickness of the liquid crystal layer is fixed to one of the first and second insulating substrates in a facing gap of the insulating substrate. A liquid crystal display device, comprising: A first substrate having a switching element for pixel selection, an electrode group including a signal wiring for supplying a pixel selection voltage to the switching element and a common wiring, and a first substrate facing the first substrate; A second insulating substrate on which at least two or more types of color filters having different colors for color display and a black matrix interposed between the color filters are formed; and a gap between the first and second insulating substrates facing each other. A liquid crystal having a sealed liquid crystal layer having a dielectric anisotropy and an alignment control layer for aligning the molecular arrangement of the liquid crystal layer in a predetermined direction at an interface between the first and second insulating substrates in contact with the liquid crystal layer. A driving voltage for driving the switching element and selecting a pixel is applied to the panel and the electrode group of the first insulating substrate to generate an electric field substantially parallel to the surface of the first insulating substrate. And a driving means for forming, wherein at least one polymer bead is covered with a resin material at a height substantially equal to a desired thickness of the liquid crystal layer in a facing gap between the first and second insulating substrates. A liquid crystal display device, wherein the columnar spacer is fixedly provided on one of the first and second insulating substrates. 3. The columnar spacer is formed of one polymer bead having a height in a direction orthogonal to a surface of the first and second insulating substrates substantially equal to a gap between the first and second insulating substrates facing each other. 3. The liquid crystal display device according to claim 1, wherein: 4. The column-shaped spacer is formed of a plurality of polymer beads having a stacking height in a direction orthogonal to a surface of the first and second insulating substrates substantially equal to a gap between the first and second insulating substrates. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is configured. 5. The liquid crystal display device according to claim 1, wherein said spacer is provided immediately below said black matrix.