KR20110044107A - In-plane switching mode transflective type liquid crystal display device - Google Patents

Abstract

PURPOSE: A rolling mode semitransparent LCD device is provided not to generate display quality deterioration without a normal black or a normal white mode about a reflection unit and a transparent unit. CONSTITUTION: A rolling mode semitransparent LCD device includes a gate wire(103), a data wire(125), a reflection thin film transistor(Tr1) and three transparent thin film transistors, a first protective layer, a reflection plate, a second protective layer, a pixel electrode, a third protective layer, a common electrode, a color filter layer, and a liquid crystal layer. The reflection thin film transistor and three transparent thin film transistor are connected to the gate wire and the data wire. The first protective layer cover the data wire and the reflection and transparent thin film transistor.

Description

In-plane switching mode transflective type liquid crystal display device

The present invention relates to a liquid crystal display device, and more particularly, to a transverse electric field mode reflection transmission type liquid crystal display device having improved aperture ratio and luminance characteristics.

In general, a liquid crystal display device is a display device using characteristics of liquid crystal molecules that differ in arrangement depending on voltage application. The liquid crystal display device can be driven at a lower power than a cathode ray tube, and is advantageous in miniaturization and thinning. BACKGROUND ART There is a spotlight as a flat panel display device such as a television, and since it is easy to carry due to its lightweight and thin characteristics, it is used as a display element of a notebook or a personal portable terminal.

In the liquid crystal display, two substrates on which electrodes are formed are disposed so that the two electrodes face each other, and a liquid crystal is generated by an electric field generated by a voltage difference applied to the two electrodes through a liquid crystal between the two substrates. By controlling the movement of molecules, it is a device that expresses an image by controlling the transmittance of light that varies accordingly.

On the other hand, the liquid crystal display device is generally a passive element that does not emit light by itself, so a separate light source is required. Therefore, in addition to the liquid crystal panel (panel) consisting of the two substrates and the liquid crystal layer (backlight) for providing a light (light) to the rear side (light) and the light emitted from the backlight is incident on the liquid crystal panel, according to the arrangement of the liquid crystal The image is displayed by adjusting the amount.

Such a liquid crystal display device is called a transmission type liquid crystal display device. Since the liquid crystal display device uses an artificial light source such as a backlight, a bright image can be realized even in a dark external environment, but a portable device is required because power must be supplied to the backlight. When used as a display device of a relatively large power consumption (power consumption) is a disadvantage.

Accordingly, a reflection type liquid crystal display device using an external light source without using a backlight has been proposed to compensate for such a disadvantage.

Since the reflective liquid crystal display device operates by using external natural light or artificial light, the power consumption of the backlight is greatly reduced, so the power consumption is relatively small compared to the transmissive type, so it can be used in a portable state for a long time. It is mainly used as a display element of a portable device such as an assistant.

However, such a reflective liquid crystal display device has an advantage of low power consumption because it does not have a separate light source, but can not be used in a place where the external light is weak or absent.

Therefore, recently, a transflective liquid crystal display device having only the advantages of a reflective liquid crystal display device and a transmissive liquid crystal display device has been proposed. In the case of such a transflective liquid crystal display device, mainly an electrically controlled birefringence (ECB) mode or It is mainly implemented in VA (vertical alignment) mode, the ECB mode has a disadvantage of low viewing angle, and VA mode also requires a large number of viewing angle compensation film to further improve the viewing angle, causing a problem of increased manufacturing cost. Doing.

On the other hand, in the case of the liquid crystal display device, due to its lightweight and thin structure, it has recently escaped from a personal display device such as a portable notebook and is widely used as a mass media such as a TV, so that a large number of users can watch from various angles instead of only an individual. Therefore, viewing angle is becoming an important issue.

Therefore, in order to overcome the disadvantages of the low viewing angles of the above-described VA mode and ECB mode liquid crystal display devices, both the common electrode and the pixel electrode are formed on the same substrate and are driven by the transverse electric field, thereby improving the range of the viewing angle. Display devices have been proposed.

FIG. 1 is a schematic cross-sectional view of a pixel area having a reflection area and a transmission area of a conventional transverse electric field mode reflection-transmissive liquid crystal display, and FIG. 2 is a view illustrating a portion cut along the cutting line II-II of FIG. 1. It is a cross section. In this case, a reflecting plate RA is formed in the pixel region P to prevent light from passing through, and a transmissive part TA through which light is transmitted is not defined.

As shown in the drawing, the gate line 3 and the data line 25 cross each other to define the pixel region P, and extend in parallel with the gate line 3. A common wiring 9 penetrating the pixel region P is formed, and each pixel region P is connected to the gate wiring 3 and the data wiring 25 and has a gate electrode 6 and a gate insulating film ( A thin film transistor Tr, which is a switching device including a semiconductor layer (not shown), and source and drain electrodes 30 and 33, is formed.

In addition, a reflector plate 50 is formed on the reflector part RA with a metal material having good reflectance, and in the pixel region P, the reflector plate 50 is formed through the drain contact hole 65. A plate-shaped pixel electrode 70 connected to the drain electrode 33 of Tr is formed.

In addition, the pixel electrode 70 is connected to the common wiring 9 through a common contact hole (not shown) through the insulating layer 72 and has a plurality of bar-shaped openings op1 and op2. A common electrode 80 having a structure is formed. In this case, the plurality of openings op1 and op2 are divided into a plurality of first openings op1 and a plurality of second openings op2 and are provided in the transmission area TA and the reflection area RA, respectively. The first and second openings op1 and op2 are characterized by varying the directions of their major axes.

In the case of the transmissive part TA, the direction of the plurality of first openings op1 is 90 degrees with respect to the gate wiring 3, and the orientation direction R1 in the transmissive area TA is the first direction. The upper plate (color filter substrate) and the lower plate (array substrate) are each about +5 degrees with respect to one opening op1.

In the case of the reflective area RA, the direction of the plurality of second openings op2 is -45 degrees based on the gate line 3, and the orientation direction of the reflective area RA is the transmission area. The upper and lower plates are +45 degrees with respect to the orientation of (TA).

In this case, the first and second polarization axes up1 and dp1 in the first and second polarizing plates 93 and 95 respectively provided on the outer surface of the conventional transverse electric field mode reflection-transmissive liquid crystal display device 1 are mutually different. The first and second polarizing plates 93 and 95 are provided to be orthogonal to each other, so that one of these polarization axes up1 and dp1 corresponds to the alignment direction R1 of the transmission area TA.

An overcoat layer 88 is formed on the front surface of the color filter layer 86 and the front surface of the color filter layer 86 so as to face the array substrate 2 having such a configuration and correspond to a black matrix (not shown) and each pixel region P at the boundary of the pixel region P. The provided color filter substrate 83 is provided, and the liquid crystal layer 90 is interposed between the array substrate 2 and the color filter substrate 83.

However, in the conventional transverse electric field mode reflection-transmissive liquid crystal display having the above-described configuration, since one pixel area P is divided into a reflecting portion RA and a transmitting portion TA, its luminance characteristics are reduced when driving in the transmissive mode. It's happening.

In addition, the conventional transflective liquid crystal display device 1 having the above-described configuration is divided into a reflection part RA and a transmission part TA in one pixel area P, and one in one pixel area P. Only the thin film transistor Tr is formed. Therefore, the reflection mode and the transmission mode must be simultaneously driven through each pixel region P driven by one thin film transistor Tr, thereby causing a limitation due to a single driving mode. For example, when driving in the integrated mode of the reflection mode and the transmission mode, both the reflection part RA and the transmission part TA must be matched to one of the normally black or normal white modes, and when they do not match, Luminance reduction and image quality deterioration occur. Therefore, in order to solve this problem, the alignment directions R1 and R2 are different in the reflection part RA and the transmission part TA as described above, and the directions of the first and second openings op1 and op2 are also different. .

That is, the transmitting part TA is λ / 2 cells, and black is realized under the condition that the major axis of the liquid crystal molecules coincides with the upper polarizer axis, and the reflecting part RA is 1/2 of the cell gap of the transmitting part TA, so λ / 4 In this case, black is realized when the major axis of the liquid crystal molecules forms a 45 degree angle with the upper polarizer axis.

Therefore, constraints such that the alignment directions R1 and R2 must be differently formed in the reflection part RA and the transmission part TA in one pixel area P occur. The splitting orientation at is due to the relatively small area, which leads to a lot of process errors, which leads to an increase in the defective rate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and provides a reflective transmissive liquid crystal display device that does not cause display quality deterioration even if the normal and black modes are not necessarily matched with the reflective part and the transparent part. The purpose is to.

Another object of the present invention is to provide a reflective transmissive liquid crystal display device which can increase the size of the unit alignment region compared with the conventional one, minimize the occurrence of errors in the process of polarization alignment, and further improve aperture ratio and luminance characteristics and reduce power consumption. Doing.

In the transverse electric field mode reflection-transmissive liquid crystal display device according to the present invention, a dot having four pixel regions adjacent to each other vertically, vertically, horizontally, and left is defined, and one of the four pixel regions provided in the dot is the other three reflective pixel regions. A gate wiring and a data wiring formed on the inner side of the first substrate defined as a transmissive pixel region by crossing the gate insulating film to define each pixel region; A reflective thin film transistor and three transmissive thin film transistors connected to the gate line and the data line; A first passivation layer covering the data line and the reflective and transmissive thin film transistor; A reflector formed in the reflective pixel area over the first passivation layer; A second protective layer formed over the reflecting plate; A drain contact hole exposing a drain electrode of each of the reflective and transmissive thin film transistors over the second passivation layer, the pixel electrode being in contact with each of the drain electrodes and formed in a plate shape in the reflective and transmissive pixel areas; A third passivation layer formed over the pixel electrode; A common electrode formed on the third passivation layer and having a plurality of bar-shaped openings corresponding to each of the reflective and transmissive pixel areas; A color filter layer formed on an inner surface of a second substrate facing the first substrate; And a liquid crystal layer interposed between the first and second substrates.

The reflective and transmissive thin film transistors are both formed in the reflective pixel region, and each pixel electrode formed in the transmissive pixel region has an extension part connected to the drain electrode of the transmissive thin film transistor formed in the reflective pixel region. The pixel electrode formed to be connected to the drain electrode of the reflective thin film transistor is formed to have a spaced interval around each of the extension portions so as not to contact the extension portions.

The reflective plate overlaps with a drain contact hole exposing each drain electrode of the reflective and transmissive thin film transistor, and has a reflective contact hole having an area larger than that of the respective drain contact hole contact holes, wherein each of the drain contact holes is the reflection. It is characterized in that it is formed to penetrate the contact hole.

A fourth passivation layer is provided in the reflective pixel region, and thus the pixel electrode formed to be connected to the drain electrode of the reflective thin film transistor and an extension of the pixel electrode provided in the transmissive pixel region are disposed with the fourth passivation layer interposed therebetween. It is characterized by being formed so as to overlap in the region.

The reflective thin film transistor is formed in the reflective pixel region, and the transparent thin film transistor is formed in the transparent pixel region.

The color filter layer may include a red, green, blue, and white color filter pattern, and the red, green, and blue color filter patterns correspond to the three pixel areas provided in the single dot, respectively, and reflect the color filter layer. In response to the pixel region, a white color filter pattern is formed to correspond to each other, or the color filter layer is formed of a red, green, and blue color filter pattern, respectively, corresponding to three pixel regions provided in the single dot. The green and blue color filter patterns correspond to each other, and the red, green, and blue color filter patterns correspond to the reflective pixel areas in a repeating order.

The thickness of the liquid crystal layer in the reflective pixel region is preferably 1/2 of the thickness of the liquid crystal layer in the transmissive pixel region.

In addition, the first protective layer is made of an organic insulating material, and the surface of the reflective pixel region has a convex-concave shape, and the reflecting plate formed on the first protective layer also has a convex-convex shape. It is characteristic.

A fifth passivation layer made of an inorganic insulating material is formed between the thin film transistor and the first passivation layer, and a sixth passivation layer made of an inorganic insulating material is formed between the first passivation layer and the reflector, and the second passivation layer is formed. A seventh passivation layer is formed between the passivation layer and the third passivation layer to correspond to the reflective region using an organic insulating material.

In addition, a black matrix is formed between the inner surface of the second substrate and the color filter layer to correspond to the gate and data wiring, and an overcoat layer is formed on the entire surface of the second substrate to cover the color filter layer. The color filter layer is patterned and removed at a central portion of the color filter layer corresponding to the reflective pixel region to form a transmission hole.

In addition, a plurality of micro lenses having a hexagonal shape is provided on a rear surface of the first substrate, and one end and the other end of the plurality of micro lenses having a triangular shape are located in the reflective pixel area and have a quadrangular shape. The central portion is disposed in the transmissive pixel region.

In this case, the micro-lenses having a plurality of hexagonal shapes are formed by patterning the first substrate itself.

The reflective and transmissive parts are configured in pixel units so that the reflective and transmissive parts have pixel electrodes connected to the thin film transistors, respectively, to control driving in the reflective and transmissive parts so that the normal black or normal white driving modes do not necessarily match. Even if there is an advantage that can implement excellent image quality.

Since the reflecting part and the transmitting part are configured for each pixel area, when the divided alignment is applied, the divided alignment is performed for a relatively large area compared to the prior art, thereby improving the yield by reducing the alignment error.

By forming all the thin film transistors that control the neighboring pixel regions in the pixel region constituting the reflecting portion, the aperture ratio of the pixel region can be improved and the luminance characteristic can be improved.

In addition, by configuring a microlens to overlap a portion of the pixel region constituting the reflecting portion, when the transmission mode is implemented, a part of the light incident from the backlight to the reflecting portion is incident to the transmitting portion to improve the luminance characteristic, or to have the same luminance characteristic as before. In this case, since the number of lamps provided in the backlight unit can be reduced, power consumption can be reduced.

Hereinafter, the transverse electric field mode reflective transmission liquid crystal display device according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 3 is a plan view of four pixel areas, ie, one dot, representing red, green, blue, and white, in the reflective transmissive liquid crystal display according to the exemplary embodiment of the present invention, and FIG. Sectional drawing of the part cut along the side. For convenience of description, the pixel area RP of the reflection plate provided with the reflection plate and the pixel area without the reflection plate are referred to as the transmission pixel area TP. In addition, a region in which the thin film transistor Tr, which is a switching element, is formed in the reflective pixel region RP is defined as a switching region TrA.

As illustrated, the transverse electric field mode reflective transmission liquid crystal display device according to the exemplary embodiment of the present invention includes an array substrate, a color filter substrate, and a liquid crystal layer interposed between the two substrates. Although not shown in the drawings, a backlight unit is provided on the rear surface of the array substrate.

First, a plurality of gate lines 103 and a plurality of data lines 125 are formed in the array substrate 101 to define a plurality of pixel regions P by crossing each other with a gate insulating layer interposed therebetween.

In addition, the reflective pixel region RP is connected to the gate wiring 103 and the data wiring 125 and has a gate electrode 106, a gate insulating film 115, an active layer 120a of pure amorphous silicon, and an impurity amorphous material. A semiconductor layer 120 made of an ohmic contact layer 120b of silicon and four thin film transistors Tr1, Tr2, Tr3, and Tr4 formed of source and drain electrodes 130 and 133 spaced apart from each other are formed. In this case, three of the four thin film transistors Tr1, Tr2, Tr3, and Tr4 control the transmissive pixel area TP positioned around the reflective pixel area RP. The thin film transistors Tr2, Tr3, and Tr4, and the other thin film transistor Tr1 become the thin film transistor Tr1 that controls the reflective pixel region RP. In this configuration, since the thin film transistor for controlling the inside of the transparent pixel area TP is not provided, the aperture ratio is improved. The reflective plate 150 is provided in the reflective pixel area RP, and the four thin film transistors Tr1, Tr2, Tr3, and Tr4 are provided below the reflective plate 150, so that the thin film transistors Tr1, Tr2, Tr3, and Tr4 are provided. The decrease in the aperture ratio by) does not occur, so it is not a problem.

On the other hand, as a modified example, the thin film transistors Tr1, Tr2, Tr3, and Tr4 may not be configured in the reflective pixel region RP, but may be formed one for each pixel region RP and TP.

In addition, a first protective layer 136 is formed as an inorganic insulating material, covering each of the thin film transistors Tr and the data line 125, and a second protective layer as an organic insulating material on the first protective layer 136. Layer 140 is formed on the front side. At this time, the second protective layer 140 is characterized in that the convex irregularities are formed on the surface of the reflective pixel region (RP).

In addition, a third passivation layer 142 is formed on the second passivation layer 140 as an inorganic insulating material, and a metal material having excellent reflectance on the reflective pixel region RP is formed on the third passivation layer 142. In one example, the reflective plate 150 is formed of any one of aluminum (Al), aluminum alloy (AlNd), and silver (Ag). At this time, the third protective layer 142 and the reflective plate 150 is characterized in that the surface of the convex concave-convex shape due to the influence of the second protective layer 140 formed on the bottom. Meanwhile, the reflective plate 150 provided in the reflective pixel region RP is patterned to correspond to an area in which the drain electrodes 133 of the four thin film transistors Tr1, Tr2, Tr3, and Tr4 are formed, respectively. Four reflection holes rh for exposing the third protective layer 142 positioned are provided.

In the embodiment of the present invention, the first, second, and third protective layers 136, 140, and 142 are shown as an example, but the first and second of the three protective layers 136, 140, and 142 are formed. 3 protective layers 136 and 142 may be omitted. The first protective layer 136 made of an inorganic insulating material has characteristics of channel contamination and thin film transistor (Tr) that may occur when the second protective layer 140 made of an organic insulating material comes into contact with the active layer 120a. The third protective layer 142 may be formed to prevent degradation, and the third protective layer 142 may include the reflective plate 150 made of a metallic material and the second made of an organic insulating material to solve the problem of weakening of adhesion between the organic insulating material and the metal material. It is formed to improve the bonding characteristics by being formed between the protective layer 140.

Next, a fourth passivation layer 152 is formed on the reflective plate 150 to correspond to the reflective pixel region RP as an organic insulating material. The fourth passivation layer 152 is formed to reduce the thickness of the cell gap of the reflective pixel region RP, that is, the liquid crystal layer 189, with respect to the transmissive pixel region TP forming the transmissive portion TA.

In this case, in the reflective pixel region RP, the fourth protective layer 152, the third protective layer 142, and the second and first protective layers 140 and 136 under the patterned portion are patterned. A drain contact hole 158 exposing the drain electrode 133 of each of the thin film transistors is provided. In this case, the drain contact hole 158 is formed to penetrate the inside of the reflection hole rh formed in the reflection plate 150. When the drain contact hole 158 is formed to have the same area as the reflection hole rh or to have a larger plane area, the side surface of the reflector 150 is exposed inside the drain contact hole 158. The reflective plate 150 is in contact with the four pixel electrodes 160 which are in contact with each of the four drain electrodes 133 to which different signal voltages are applied, respectively, which causes short circuits. Therefore, to prevent this, the reflection hole rh is configured to have a larger planar area than the drain contact hole 158.

 Next, a plate-shaped pixel electrode 160 is formed in each of the pixel areas RP and TP from the fourth passivation layer 152 and the transparent conductive material. At this time, except for the pixel electrode 160 formed in the reflective pixel region RP, all of the pixel electrodes 160 formed in the transparent pixel region TP extend to the reflective pixel region RP. 161b, 161c, and each of the extension parts 161a, 161b, and 161c to the portion where the drain electrode 133 of each of the thin film transistors Tr2, Tr3, and Tr4 controls the transmissive pixel region TP. It extends and contacts each drain electrode 133 through each drain contact hole 158 exposing each drain electrode 133.

On the other hand, although not shown, in the modified example in which one thin film transistor is formed in each pixel region, the pixel electrode does not have an extension portion and drains each thin film transistor through a drain contact hole provided in each pixel region. It is formed in contact with the electrode.

On the other hand, the pixel electrode 160a formed in the reflective pixel region RP is a pixel electrode extension part connected to each drain electrode 133 of the thin film transistors Tr2, Tr3, and Tr4 for controlling the neighboring transparent pixel region TP. Since the 161a, 161b, and 161c are configured, the drain contact hole exposing the drain electrode 133 in contact with the reflective pixel electrode 160a to prevent a short from the pixel electrode connection parts 161a, 161b, and 161c. It is characterized by not being formed around the three remaining drain contact holes 158b, 158c, and 158d except for 158a.

Meanwhile, as another modified example, FIG. 5 (a plan view of four pixel areas, i.e., one dot, representing red, green, blue, and white of the reflective transmissive liquid crystal display device according to the embodiment of the present invention) is shown in FIG. Like reference numerals denote the same elements), and the extending pixel portions 161a, 161b, and 161c formed in the transparent pixel region TP are also formed in the reflective pixel region RP. It may also be formed in the form of pixel electrodes 160b, 160c, 160d having a shape other than). In this case, the drain contact is formed on the fourth passivation layer (not shown) and exposes the drain electrode 133 of the thin film transistor Tr1 that controls the reflective pixel region RP. The hole 158a may be formed, and the reflective pixel electrode 160a may be formed on the fifth passivation layer (not shown). In this case, in the reflective pixel region RP, the reflective pixel electrode 160a is formed to overlap the pixel electrode extension portions 161a, 161b, and 161c formed on the fourth passivation layer (not shown). Since the reflective pixel electrode 160a and the pixel electrode extension portions 161a, 161b, and 161c are formed on different layers, shorts do not occur, and thus, the problem is not a problem.

Meanwhile, in the first exemplary embodiment, a sixth passivation layer 163 is formed on the pixel electrode 160 as an inorganic insulating material, and a display area is formed on the sixth passivation layer 163 as a transparent conductive material. A common electrode 170 having a plurality of bar-shaped openings oa is formed on the front surface of each pixel area TP and RP.

Although not shown in the drawings, a first alignment layer (not shown) is provided on the common electrode 170 having the openings oa having the plurality of bars.

The color filter substrate 181 is provided corresponding to the array substrate 102 having the above-described configuration.

On the inner surface of the color filter substrate 181 facing the array substrate 102, a black matrix 183 is formed to correspond to the boundary of each pixel region P, that is, the gate and data lines 103 and 125. And a white color covering the black matrix 183 and corresponding to the red, green, and blue color filter patterns R, G, and B, and the reflective pixel region RP, respectively, corresponding to each of the transparent pixel regions TP. The color filter layer 185 formed of the Filton W is formed. In this case, although not shown in the drawings, the color filter layer 185 may be patterned and removed to correspond to the central portion of each reflective pixel region RP, so that a transmission hole (not shown) may be provided. The configuration of the transmission holes (not shown) in the reflective pixel region RP is to improve luminance in the reflective pixel region RP.

An overcoat layer 187 is formed over the color filter layer 185 and over the color filter substrate 181. A second alignment layer (not shown) is provided to cover the overcoat layer 187. On the other hand, the white color filter pattern (W) in the drawing is shown to consist substantially of the overcoat layer 187, but is formed as a colorless color resist, characterized in that separate red, green, blue pigments are removed. It may be.

In this case, the first and second alignment layers (not shown) are UV-aligned to have different alignment angles corresponding to the transmission pixel region TP and the reflective pixel region RP, respectively, or aligned to have the same alignment direction at an angle. It is characterized by being processed. When the alignment process is performed to have the same alignment direction corresponding to the reflective pixel region RP and the transparent pixel region TP, it is not necessary to be processed through UV alignment, but a rubbing process may be performed to have the same alignment direction on the entire surface. May be

When the divided alignment is required to have different orientation angles corresponding to the reflective pixel region RP and the transparent pixel region TP, UV alignment is performed by irradiating UV light in each pixel region TP and RP through the UV alignment apparatus. By processing, the alignment direction is different for each of the reflective and transmissive pixel regions RP and TP. In this case, the area irradiated through the UV beam irradiator (not shown) is about 1/2 of the pixel area in the related art, but in the case of the present invention, since the size of one pixel area RP and TP becomes larger than the conventional resolution margin, By doubling, the error of UV alignment can be reduced through the UV beam irradiation device that requires fine control.

 Meanwhile, a liquid crystal layer having a first thickness between the first and second alignment layers (not shown) and having a second thickness smaller than the first thickness in the reflective pixel region RP. 189 is provided. At this time, the second thickness is characterized in that 1/2 of the first thickness.

In addition, first and second polarizers (not shown) having polarization axes orthogonal to each other are provided on the outer surfaces of each of the array substrate 102 and the color filter substrate 181, and are disposed below the first polarizer (not shown). Since the backlight unit (not shown) including a light source and a plurality of optical sheets (not shown) is provided, the transverse electric field mode reflective transmission liquid crystal display device 101 according to the first embodiment of the present invention is completed.

In the transverse electric field mode reflection-transmissive liquid crystal display device 101 according to the first embodiment of the present invention having the above-described configuration and modified examples thereof, the reflection unit and the transmission unit are formed for each pixel area RP and TP to independently reflect the reflection mode. And transmissive mode. When the reflection mode and the transmissive mode are simultaneously implemented, signal voltages suitable for the reflective pixel area RP and the transparent pixel area TP can be applied, so that display quality is not degraded. to be.

Meanwhile, in the drawing, the white color filter pattern W is provided in the reflective pixel region RP, and the red, green, and blue color filter patterns R, G, and B are respectively disposed in the three adjacent transparent pixel regions TP. ), But the arrangement of the red, green, blue and white color filter patterns (R, G, B) can be freely changed.

In the first exemplary embodiment of the present invention, the white color filter pattern W is disposed corresponding to the reflective pixel region RP, so that the image is implemented in black and white when the reflective mode is driven. When the red, green, and blue color filter patterns are arranged in the RP), a full color image may be realized even when driving in the reflection mode.

6A and 6B illustrate that red, green, blue, and white color filter patterns R, G, B, and W are disposed in a transverse electric field mode reflective transmissive liquid crystal display according to a modification of the first embodiment of the present invention. Figure is shown.

Referring to FIG. 6A, a transverse electric field mode reflection-transmissive liquid crystal display device according to a modified example configures a dot, which is a minimum unit in which four pixel areas adjacent to each other vertically, horizontally, left, and right, represent one full color. And one reflective pixel region RP and three transmissive pixel regions TP. In this case, the transverse electric field reflection type liquid crystal display device according to the modified example has three color filter patterns (R, G, B) of red, green, and blue without a white color filter pattern to realize full color even when driving in the reflection mode. It is characterized by being composed only of). That is, the red, green, and blue color filter patterns R, G, and B are sequentially repeated in correspondence to the transmission pixel region TP, and are also repeated in the dot unit corresponding to the reflective pixel region RP. The red, green, and blue color filter patterns R, G, and B are formed in a repeating form.

In this case, the arrangement of the red, green, and blue color filter patterns R, G, and B may be freely changed in addition to those shown in the drawings, even in the transverse electric field mode reflection-transmissive liquid crystal display device. will be.

In addition, as illustrated in FIG. 6B, the transverse electric field mode transmissive type liquid crystal display according to another modified example includes the red, green, and blue color filter patterns R, G, and B for the reflective pixel region RP. Including the white color filter pattern E, the red, green, blue, and white color filter patterns R, G, B, and W may be sequentially formed in a dot unit.

In the transverse electric field mode reflection-transmissive liquid crystal display device according to the modification of the first embodiment described above, a reflective pixel region and a transparent pixel region are formed in pixel units, and a thin film transistor for controlling each of the transparent pixel regions and the reflective pixel region is provided. Therefore, the reflection mode and the transmission mode driving can be completely separated, and even if the reflection mode and the transmission mode are driven simultaneously, the optimized signal voltage can be controlled by the thin film transistor which drives each pixel area independently. In the transmissive pixel region, display degradation does not occur even if the normal black or normal white modes are not matched.

Therefore, since there is no restriction for the normal to match the black or the normal white to the reflective part and the pixel part, the degree of freedom of design is improved. Furthermore, in the case where one reflective pixel region and three transparent pixel regions constitute one dot, a thin film transistor for controlling three adjacent transparent pixel regions is formed in the reflective pixel region to improve the aperture ratio of the transparent pixel region to thereby improve the transmittance. And brightness can be improved.

FIG. 7 is a schematic plan view of an arrangement of microlenses in a transverse electric field mode transmissive liquid crystal display according to a second exemplary embodiment of the present invention, and FIG. 8 is a transverse electric field mode reflector according to a second embodiment of the present invention. 9 is a schematic cross-sectional view of a transmissive liquid crystal display, and FIG. 9 is a plan view of a micro lens configured in a transverse electric field mode reflective transmission liquid crystal display according to a second embodiment of the present invention.

In the transverse electric field mode reflection-transmissive liquid crystal display device according to the second embodiment of the present invention, the configuration of the panel provided with the array substrate, the color filter substrate, and the liquid crystal layer is the same as that of the above-described first embodiment and modifications thereof. The description of the elements will be omitted and only the microlenses with differentiation points and their arrangement will be described.

A configuration different from that of the first embodiment of the transverse electric field mode reflection-transmissive liquid crystal display device 201 according to the second embodiment includes a plurality of micro lenses having a rectangular shape on the rear surface of the array substrate 202. 293) being deployed. Since the plurality of micro lenses 293 have a role of making a path of light to be incident from the backlight unit 297 to the reflective pixel region RP to the transmissive pixel region TP, the arrangement is very important. Therefore, it is desirable to form the rectangular micro lens 293 by patterning the back surface of the array substrate 202 itself in a specific shape. A plurality of the rectangular hexagonal microlenses 293 are arranged so that the ends of the triangular shape are positioned in the reflective pixel area and the reflective pixel area, and the half of the reflective pixel area is a transmissive pixel having its upper, lower, left, and right reflection positions. The area TP reflecting pixel is characterized in that the ends of the four rectangular hexagonal microlenses 193 arranged so as to be in contact with each other are arranged. In order to achieve such an arrangement, the rectangular hexagonal microlens 193 has an area in which a central portion having a rectangular shape corresponds exactly to one transparent pixel region TP, and the reflective pixel region RP and the transparent pixel. The region TP is characterized by forming a square shape.

Since a micro hexagonal lens 293 having a regular hexagonal shape is provided, a part of the light exiting from the backlight unit 297 and entering the reflective pixel region RP is divided into incident pixel regions TP of up, down, left, and right adjacent to each other, thereby being transmitted. When operating in mode or in integrated mode, brightness characteristics can be improved.

Light incident from the backlight unit 297 to the reflective pixel region RP is blocked by the reflector 250 provided in the reflective pixel region RP, which is a negative factor in luminance characteristics when operating in the transmission mode. In the second exemplary embodiment of the present invention, the light incident from the backlight unit 297 into the reflective pixel region RP is collected by the microlens 193 and is incident on the transparent pixel region TP positioned near the backlight unit. Since the light emitted from the 297 eventually comes to the transmissive pixel region TP, the luminance capacity of the backlight unit 297 can be maximized.

Therefore, when the transmission mode is implemented, the luminance is improved, and when maintaining the same level of brightness as before, the luminance capacity of the backlight unit, that is, the number of light sources can be reduced, so that power consumption for light emission can be reduced. to be.

 The present invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a plan view of one pixel area of a conventional transverse electric field mode reflection-transmissive liquid crystal display device, showing only components of an array substrate.

2 is a simplified cross-sectional view of a reflection area and a transmission area of a conventional transverse electric field mode reflection type liquid crystal display device.

3 is a plan view of four pixel areas, ie, one dot, representing red, green, blue, and white, in a reflective liquid crystal display according to an exemplary embodiment of the present invention;

4 is a cross-sectional view of a portion cut along the cutting line IV-IV of FIG.

FIG. 5 is a plan view of four pixel areas, i.e., one dot, representing red, green, blue, and white, in a reflective liquid crystal display according to an exemplary embodiment of the present invention; FIG.

6A and 6B illustrate that red, green, blue, and white color filter patterns R, G, B, and W are disposed in a transverse electric field mode reflective transmissive liquid crystal display according to a modification of the first embodiment of the present invention. Figure shown.

FIG. 7 is a schematic plan view of an arrangement of micro lenses in a transverse electric field mode reflective transmission liquid crystal display according to a second embodiment of the present invention; FIG.

8 is a schematic cross-sectional view of a transverse electric field mode reflective transmission liquid crystal display device according to a second embodiment of the present invention.

Fig. 9 is a plan view of a micro lens constructed in a transverse electric field mode reflective transmissive liquid crystal display device according to a second embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

101: liquid crystal display 103: gate wiring

106: gate electrode 125: data wiring

130: source electrode 133: drain electrode

150: reflector plate 158a, 158b, 158c, 158d: drain contact hole
160a, 160b, 160c, 160d: pixel electrode

161a, 161b, 161c: pixel electrode extension

oa: aperture RP: reflective pixel region

TP: Tr1, Tr2, Tr3, Tr4: Thin Film Transistor

Claims (16)

Dots having four pixel regions adjacent to each other up, down, left, and right are defined, and one of the four pixel regions provided in the dot is a reflective pixel region, and the other three gates are formed on an inner surface of the first substrate defined as a transmission pixel region. Gate wiring and data wiring crossing each other via an insulating film to define each pixel area; A reflective thin film transistor and three transmissive thin film transistors connected to the gate line and the data line; A first passivation layer covering the data line and the reflective and transmissive thin film transistor; A reflector formed in the reflective pixel area over the first passivation layer; A second protective layer formed over the reflecting plate; A pixel electrode in contact with each of the drain electrodes through a drain contact hole exposing the drain electrodes of each of the reflective and transmissive thin film transistors over the second protective layer and formed in a plate shape in the reflective and transmissive pixel areas; A third passivation layer formed over the pixel electrode; A common electrode formed on the third passivation layer and having a plurality of bar-shaped openings corresponding to each of the reflective and transmissive pixel areas; A color filter layer formed on an inner surface of a second substrate facing the first substrate; Liquid crystal layer interposed between the first and second substrate Transverse electric field mode reflective transmission liquid crystal display device comprising a. The method of claim 1, The reflective and transmissive thin film transistors are both formed in the reflective pixel region, and each pixel electrode formed in the transmissive pixel region has an extension part connected to a drain electrode of the transmissive thin film transistor formed in the reflective pixel region. Mode reflection type liquid crystal display device. The method of claim 2, And a pixel electrode formed in the reflective pixel area and connected to the drain electrode of the reflective thin film transistor with a spaced interval around each of the extension parts so as not to contact the extension parts. The method of claim 1, The reflective plate overlaps with a drain contact hole exposing each drain electrode of the reflective and transmissive thin film transistor, and has a reflective contact hole having an area larger than that of the respective drain contact hole contact holes, wherein each of the drain contact holes is the reflection. A transverse electric field mode transmissive liquid crystal display device characterized in that it is formed to penetrate a contact hole. The method of claim 1, A fourth passivation layer is provided in the reflective pixel region, and thus the pixel electrode formed to be connected to the drain electrode of the reflective thin film transistor and an extension of the pixel electrode provided in the transmissive pixel region are disposed between the fourth passivation layer and the reflective pixel. A transverse electric field mode transmissive liquid crystal display device characterized in that it is formed to overlap in an area. The method of claim 1, And wherein the reflective thin film transistor is formed in the reflective pixel region, and the transparent thin film transistor is formed in the transmissive pixel region. The method of claim 1, The color filter layer is formed of a red, green, blue, and white color filter pattern, and the red, green, and blue color filter patterns correspond to three pixel areas provided in the single dot, respectively, and the reflective pixel area. The transverse electric field mode reflection type transmissive liquid crystal display device which is configured to correspond to the white color filter pattern. The method of claim 1, The color filter layer may be formed of a red, green, and blue color filter pattern, and correspond to the red, green, and blue color filter patterns respectively corresponding to three pixel areas provided in the single dot, and correspond to the reflective pixel area. The transverse electric field mode reflection-transmissive liquid crystal display device is characterized in that the red, green, and blue color filter patterns are sequentially and repeatedly arranged in dots. The method of claim 1, And a thickness of the liquid crystal layer in the reflective pixel region is one-half the thickness of the liquid crystal layer in the transmissive pixel region. The method of claim 1, The first passivation layer is made of an organic insulating material, and the reflective pixel region has a convex concave-convex surface, and the reflecting plate formed on the first passivation layer also has convex concave-convex shape. Transverse electric field mode semi-transmissive liquid crystal display device. The method of claim 1, A fifth protective layer made of an inorganic insulating material is formed between the thin film transistor and the first protective layer. And a sixth passivation layer formed of an inorganic insulating material between the first passivation layer and the reflection plate. The method of claim 11, And a seventh passivation layer formed of an organic insulating material between the second passivation layer and the third passivation layer to correspond to the reflecting region. The method of claim 1, A black matrix is formed between the inner surface of the second substrate and the color filter layer to correspond to the gate and data wirings. A transverse electric field mode transmissive liquid crystal display device covering the color filter layer and having an overcoat layer formed on the entire surface of the second substrate. The method of claim 13, And the color filter layer is patterned and removed at a central portion thereof corresponding to the reflective pixel region to form a transmission hole. The method according to any one of claims 1 to 14, A plurality of micro lenses having a hexagonal shape is provided on a rear surface of the first substrate, and one end and the other end of the plurality of micro lenses having a triangular shape are located in the reflective pixel area, and a central portion having a quadrangular shape is provided. And a transverse electric field mode reflective transmission type liquid crystal display device disposed in said transmissive pixel region. The method of claim 15, The micro-lens having a plurality of hexagonal shapes is formed by patterning the first substrate itself.

Images