KR20050037685A - High-brightness transflective liquid crystal display apparatus - Google Patents

Abstract

A transflective liquid crystal display device having four color filters of red, green, blue, and white is disclosed. The liquid crystal display of the present invention comprises a color filter constituting one color pixel by combining at least three or more colored layers each colored with a different fluid color and one colored layer colored white, and a part of each colored layer. And a reflective layer formed corresponding to the region, a transmissive layer formed corresponding to the remaining partial region of each colored layer, and a liquid crystal layer injected between the reflective layer and the corresponding colored layer. Therefore, by controlling the area ratio of the transmissive layer and the reflective layer corresponding to the white colored layer, it is possible to minimize the difference between the reflective display and the transmissive display as well as the high brightness display effect.

Description

High-Brightness Transflective Liquid Crystal Display Apparatus}

The present invention relates to a high luminance semi-transmissive liquid crystal display device, and more particularly, to achieve high luminance in the transflective type, while minimizing the difference between the reflective display and the transmissive display. It relates to a display device.

Liquid crystal displays are being used for various purposes such as notebook computers, portable information terminals, desktop monitors, digital cameras, etc. due to their small size, light weight, and low power consumption.

Liquid crystal display devices using a backlight are required to increase the efficiency of the backlight in order to promote low consumption and low power. To this end, the transmittance of the color filter is improved year by year in response to the demand of the high transmittance of the color filter, but it is difficult to expect a significant reduction in the power consumption of the liquid crystal display device due to the improvement of the transmittance of the color filter.

Therefore, in recent years, the development of a reflective liquid crystal display device which does not require a backlight having a large power consumption is in progress, and the reflective liquid crystal display device can significantly reduce power consumption as compared to a transmissive liquid crystal display device. The reflection type liquid crystal display device has the advantage of lower power consumption and excellent screen display in the outdoor compared to the transmission type liquid crystal display device, but has a problem in that the screen display is degraded because the display is dark in a place without sufficient external light intensity. Therefore, in order to display the screen excellently even in dark conditions, a semi-transmissive liquid crystal display device having a transmission mode and a reflection mode is introduced by installing a backlight and creating a transmission window through which light can pass through a part of the reflection electrode. It is becoming.

A general transflective liquid crystal display device has a transmissive mode for displaying a screen using the backlight 10 and a reflection mode for displaying a screen using external light, as shown in FIG. 1. In the transflective liquid crystal display, the transmission region 12 and the reflection region 14 exist, and the color of the transmission region is displayed in the transmission mode, and the color of the reflection region is displayed in the reflection mode. In the transmissive mode, the backlight light 16 passes through the transmissive region 12 of the color filter 18 once. In the reflection mode, the external light 20 passes through the reflection region 14 of the two-color color filter 18 which is incident and reflected.

That is, since the number of transmissions of the color filter in the transmissive display and the reflective display is different, when the color material of the transmissive region and the reflecting region is made the same, the density of the displayed color, that is, the color purity and brightness is displayed. It is shown differently in the display. In the transmissive display, the light source is the backlight, whereas in the reflective display, the light source is the external light, so that not only the color purity but also the color tone is displayed differently in the transmissive display and the reflective display.

As a method of making the display color of the transmission area and the reflection area the same, a two-tone color system in which the reflection area 14 and the transmission area 12 of the color filter 18 are composed of different tones. Method) is introduced. However, in the two-tone color system, when the color filter is manufactured in three colors, two-tones must be formed for each color, and thus a manufacturing cost increases because a process of applying a total of six color materials is required.

As another method of making the color density (color reproducibility) of the transmissive display and the reflective display the same, a technique of varying the film thickness of the colored layer in the transmissive region and the reflective region has been introduced.

However, only by varying the thickness of the colored layer, the light source in the transmissive display is the backlight light, and in the reflective display, the light source cannot correct the color tone change according to the external light. Therefore, the difference in color purity and brightness can be eliminated only by changing the film thickness of the colored layer of the reflective region 14 thinly. This is different from the color tone, and it is difficult to display the screen in the reflective display and the transparent display.

The prior art which solves the problem mentioned above, and provides the color filter with the difference of the brightness and color of a transmissive display and a reflective display, and at the same time is inexpensive is described. It is the color filter of the light hole type | mold provided with the transparent area | region in the reflecting area described in Unexamined-Japanese-Patent No. 2000-111902. The said invention has the effect equivalent to thinning the film thickness of a colored layer by providing a transparent area | region. According to the above method, since the processing is done once per color, the processing can be performed in the same process water as the usual color filter, and the problem of high manufacturing cost does not occur.

However, a problem of the color filter in the form of a light hole is that a step occurs on the surface of the color filter by providing a transparent region without a colored layer. A basic characteristic that has a significant effect on the display performance of the liquid crystal display device is a cell gap. Since the level difference on the surface of the color filter is a change in the cell gap directly, it is preferable that the level difference is as small as possible. In addition, since the flatness of the color filter becomes worse as the step height increases, there is a problem in the alignment process, and there is a fear that display defects may occur when used in the liquid crystal panel.

An object of the present invention is to solve the problems of the prior art, one color pixel is composed of four color sums, one of the four color sums to white color and optimize the area ratio of the white transmission area and reflection area The present invention provides a high brightness semi-transmissive liquid crystal display device capable of achieving high brightness while minimizing the difference between reflective display and transmissive display.

An apparatus of the present invention for achieving the above object is a color filter constituting one color pixel by combining at least three or more colored layers each colored with a different fluid color and one colored layer colored white, A liquid crystal layer injected between a reflective region formed corresponding to a partial region of each of said colored layers, a transmissive region formed corresponding to the remaining partial regions of each colored layer, and a colored layer corresponding to the reflective region and the transmissive region; It features.

In the present invention, it is preferable that the area ratio of the reflection area and the transmission area corresponding to the white colored layer is optimized to the area ratio which minimizes the difference between the transmission display and the reflection display of one color pixel. Optimization of the area ratio is done through experiments. In the present invention, at least three or more colored layers of different fluid colors are preferably composed of a red layer, a green layer, and a blue layer.

In the present invention, it may be configured as a double cell gap in which the distance between the colored layer and the corresponding reflective area is smaller than the distance between the colored layer and the corresponding transmissive area.

Further, in the present invention, the interval between the transmission region and the reflection region corresponding to the colored layer is the same, and the liquid crystal driving voltage between the transmission region corresponding to the colored layer and the liquid crystal driving voltage between the reflection region corresponding to the colored layer is The difference may be configured by a dual gamma correction characteristic optimized by a voltage difference that minimizes the difference between the transmissive display and the reflective display of one color pixel.

Hereinafter, the present invention will be described in more detail with reference to the drawings and specific examples. However, the present invention is not limited to these examples.

2 to 4 are layout views of RGBW showing a relationship between a color filter and a reflection and transmission region of the high brightness transflective liquid crystal display according to the present invention.

Referring to FIG. 2, the color pixel CPX1 includes four unit pixels UPX1 of RGBW, and each unit pixel UPX1 includes a hatched reflection region RR and other transmission regions TR. do. Referring to FIG. 3, the color pixel CPX2 includes four unit pixels UPX2 of RGBW, and each unit pixel UPX2 includes a shaded reflective region RR and the other transmissive region TR. Include. Referring to FIG. 4, the color pixel CPX3 includes four unit pixels UPX3 of RGBW, and each unit pixel UPX3 includes a shaded reflective region RR and the other transmissive region TR. Include.

The white layer color filter of the present invention is formed larger in the reflection region RRW than in the transmission region TRW to minimize the display difference between the reflection mode and the transmission mode.

In the arrangement combination of FIG. 2, the width of each unit pixel is narrower than that of the conventional RGB three-color combination, so that the aperture ratio of the unit pixel is narrow. The data wiring is increased by 4/3 times, but the gate wiring is the same as in the prior art, so there is no resolution degradation. Since the RGB area becomes narrower in the area of the color pixel CPX1, the purity is lowered but the luminance of the color pixel is increased because there is a white unit pixel.

In the arrangement combination of FIG. 3, the width of each unit pixel is doubled as compared to the conventional RGB three-color combination, and thus the aperture ratio of the unit pixel is doubled. Since the data wiring is reduced by 1/2, and the gate wiring is the same as in the related art, the resolution is lowered. Since the area of the color pixel CPX2 is increased by 8/3 times and the white unit pixel exists, the luminance of the color pixel increases without deterioration of the pure color.

In the arrangement combination of FIG. 4, the width of each unit pixel is increased as compared with the conventional RGB three-color combination, but the width of the unit is reduced by 1/2 times, so that the aperture ratio in the unit pixel is narrowed. The data wiring is reduced by 2/3 times, but the gate wiring is doubled, so there is no resolution degradation. In the area of the color pixel CPX3, the area of RGB is narrowed so that the purity is lowered, but since the white unit pixel exists, the luminance of the color pixel is increased.

Accordingly, the present invention improves the overall luminance as compared with the conventional RGB three-color transflective liquid crystal display device.

In addition, the area ratio of the reflective region RRW and the transparent region TRW in the white unit pixel can be adjusted to minimize the difference between the reflective display and the transmissive display. Thus, the display difference in the conventional transflective liquid crystal display can be reduced. It can be easily optimized.

5 is a plan view illustrating a unit pixel of an exemplary embodiment of a dual cell gap high brightness semi-transmissive liquid crystal display according to the present invention. In particular, a unit pixel of a thin film transistor substrate of a transflective liquid crystal display device having an indium tin oxide (ITO) structure at a top will be described.

Referring to FIG. 5, the thin film transistor substrate is stretched in a horizontal direction on a transparent substrate (not shown), and includes a plurality of gate wires 109 arranged in a vertical direction, and extended in a vertical direction and arranged in a horizontal direction. A gate electrode 110 formed in each pixel region defined by the plurality of data lines 119 and extending from the gate line 109, a source electrode 120 and a source electrode 120 extending from the data line 119. Thin film transistor (TFT) having a drain electrode (130) spaced apart from each other, a pixel electrode (150) connected to the drain electrode 130, and a reflective electrode (164) formed on the pixel electrode (150) to reflect natural light And a reflection area and a transmission area 145 for transmitting the backlight light.

It is preferable to form a plurality of grooves and grooves in the reflective electrode 164 to increase reflection efficiency.

FIG. 6 is a cross-sectional view taken along a cutting line of AA ′ of FIG. 5.

Referring to FIG. 6, the transflective liquid crystal display includes a thin film transistor substrate 100, a color filter substrate 200, and a liquid crystal layer 300 formed between the thin film transistor substrate 100 and the color filter substrate 200.

The thin film transistor substrate 100 may include a gate electrode 110 formed on the transparent substrate 105, a gate insulating layer 112 formed on the gate electrode 110, a semiconductor layer 114, an ohmic contact layer 116, and a source electrode ( A thin film transistor (TFT) including a 120 and a drain electrode 130, and an organic insulating film 144 formed on the thin film transistor (TFT) to cover the thin film transistor (TFT) and expose a portion of the drain electrode 130. Here, it is preferable to form a plurality of grooves and grooves on the surface of the organic insulating film 144 to increase reflection efficiency.

In addition, the thin film transistor substrate 100 may include a pixel electrode 150 connected to the drain electrode 130 through a contact hole 141 by opening a portion of the thin film transistor substrate 100 through the contact hole 141, and on the pixel electrode 150. Formed reflective electrode 164. In this case, a region where the reflective electrode 164 is formed is defined as a reflective region. The organic insulating layer 144 is removed to define a region where the reflective electrode 164 is not formed as the transmission region 145.

The pixel electrode 150 is a kind of transmission electrode that transmits light, and indium tin oxide (ITO), tin oxide (TO), or indium zinc oxide (IZO) is used. Although not shown, before the pixel electrode 150 is formed, a separate capacitor wiring is formed in an area spaced from the thin film transistor TFT by a predetermined distance to define the capacitor wiring and the pixel electrode as the storage capacitor Cst. .

On the other hand, the color filter substrate 200 is a black matrix layer (not shown) defining pixel regions of R, G, B, and W on the transparent substrate 205 and coloring formed in the region defined by the black matrix layer. A layer 210 and a surface protection layer (not shown) applied to protect the black matrix layer and the colored layer 210. In the present invention, the colored layer 210 is formed to have the same thickness in the reflection area and the transmission area.

Of course, the black matrix function may be provided by overlapping adjacent colored layers 210 without forming the black matrix layer. In addition, a common electrode layer, which is not shown, may be further formed on the surface protection layer, that is, the surface close to the liquid crystal layer 300.

Meanwhile, the liquid crystal layer 300 is formed between the thin film transistor substrate 100 and the color filter substrate 200, so that the power supply applied to the pixel electrode 150 of the thin film transistor substrate 100 and the color filter substrate 200 are common. In response to a power applied to the electrode layer (not shown), natural light passing through the color filter substrate 200 may be transmitted or artificial light passing through the transmission window 170 may be transmitted. In this case, the liquid crystal layer 300 includes a liquid crystal layer corresponding to a region in which the contact hole 141 is formed, a liquid crystal layer corresponding to a region in which the contact hole 141 is not formed, and a liquid crystal layer corresponding to the transmission region. Each liquid crystal layer may be distinguished from each other, and each liquid crystal layer may have a different cell gap. Here, the cell gap of the liquid crystal layer corresponding to the region where the contact hole 141 is formed is defined as d1, and the cell gap of the liquid crystal layer corresponding to the region where the contact hole 141 is not formed is defined as d2 and corresponds to the transmission window 170. When the cell gap of the liquid crystal layer is defined as d3, the condition of d2 < d1 &lt;

In particular, when the anisotropic refractive index of the liquid crystal molecules constituting the liquid crystal layer is Δn and the cell gap is d, the organic insulating layer is not formed in the region where the contact hole is formed in the reflective region, so that the liquid crystal layer 300 is Δnd1. Since the organic insulating layer having a higher thickness is formed in the region where the contact hole is not formed, the liquid crystal layer 300 has a characteristic of Δnd2 and the organic insulating layer having a lower thickness is formed in the transmission region. The liquid crystal layer 300 corresponding to the transmission region has a characteristic of Δnd3.

The optimal cell gaps for the reflective and transmissive regions vary depending on the conditions of the liquid crystal molecules forming the liquid crystal layer 300 or the optical films provided on both upper and lower sides of the liquid crystal layer 300, but the cell gaps d2 corresponding to the reflective regions. ) Is smaller than 1.7 µm, and the cell gap d3 corresponding to the transmission region is preferably smaller than 3.3 µm.

7 is a plan view illustrating a multi-cell gap reflection-transmissive liquid crystal display device according to an exemplary embodiment of the present invention. In particular, a thin film transistor substrate for a reflection-transmissive liquid crystal display device having a top ITO structure will be described.

Referring to FIG. 7, a thin film transistor substrate according to an exemplary embodiment of the present invention may include a first light blocking pattern 413 and a data line formed when the gate line 409, the data line 419, and the gate line 409 are formed. 419) a second light blocking pattern 422, a thin film transistor (TFT), a pixel electrode 450, and a reflective plate 460 defining a reflective region and a transmission window 445.

The gate wiring 409 extends in the horizontal direction on the substrate (not shown) and is arranged in the vertical direction, and the data wiring 419 extends in the vertical direction and is arranged in the horizontal direction.

The first light blocking pattern 413 is formed in a floating state when the gate wiring 409 is formed. The first light blocking pattern 413 extends in a vertical direction so that a portion of the first light blocking pattern 413 overlaps with the data wiring 419 to be formed thereon when viewed in plan view. Is arranged. The first light blocking pattern 413 blocks afterimages and light leakage generated through the left vertical side of the transmission window 445 when the rubbing direction is approximately left to right when viewed in a plan view.

The second light blocking pattern 422 is formed in a floating state when the data line 419 is formed. The second light blocking pattern 422 extends in the horizontal direction so that a portion of the second light blocking pattern 422 overlaps with the gate line 409 formed at the bottom when viewed in plan view. Are arranged. The second light blocking pattern 422 blocks afterimages and light leakage that are generated through the upper horizontal side of the transmission window 445 when the rubbing direction is directed from the lower side to the upper direction when viewed in a plan view.

The thin film transistor TFT is formed in each region defined by the gate wiring 409 adjacent to each other and the data wiring 419 adjacent to each other, and extends from the gate electrode 410 and the data wiring extending from the gate wiring 409. A source electrode 420 extending from 419 and a drain electrode 430 spaced apart from the source electrode 420.

The pixel electrode 450 is formed in each region defined by the gate line 409 adjacent to each other and the data line 419 adjacent to each other, and is connected to the drain electrode 430 through the contact hole 441.

The reflective plate 460 is formed on the pixel electrode 450 to define a reflection area for reflecting natural light and a transmission area or transmission window 445 for transmitting artificial light, and extend from a predetermined area of an edge of the reflection area to the transmission area. To be connected to the pixel electrode 450.

The reflective plate 460 is formed in a region corresponding to the reflective region, and extends into the transmission window 445 in consideration of the rubbing direction of the alignment layer (not shown) and is connected to the pixel electrode 450 disposed below. In particular, in the drawing, when viewed from an observer's point of view, it is assumed that the alignment film is subjected to rubbing in the 10 o'clock direction, and the transmission window 445 is formed at a predetermined area of the edge of the reflection area adjacent to the lower side and the right side of the transmission window 445. It is shown that it is extended to be connected to the pixel electrode 450 provided in the lower portion.

Although not illustrated in the above drawings, when the independent wiring method is employed, the lower metal formed in the area covered by the reflector 460 when the gate wiring 409 is formed and the lower metal formed when the data wiring 419 is formed. It is preferable to define the storage capacitor Cst through the formed upper metal. The storage capacitor Cst and the pixel electrode 150 are connected through a predetermined contact hole to charge the charge provided from the drain electrode via the pixel electrode 150, and discharge the charged charge for one frame to display the display state. Keep it.

FIG. 8: shows sectional drawing cut | disconnected by the cutting line BB 'of FIG. In particular, a top ITO liquid crystal display device is shown.

Referring to FIG. 8, a reflective-transmissive liquid crystal display device according to an embodiment of the present invention may include a thin film transistor substrate 400, a color filter substrate 200, and a thin film transistor substrate 400 and a color filter substrate 200. The upper liquid crystal layer 300, the upper λ / 4 phase retardation film 40 disposed on the color filter substrate 200, the upper polarizer 50, and the lower λ disposed under the thin film transistor substrate 400. And / 4 phase retardation film (60), and lower polarizing plate (70).

The thin film transistor substrate 400 may include a gate electrode 410 formed on the transparent substrate 405, a gate insulating layer 412, a semiconductor layer 414, and an ohmic contact layer 416 formed on the transparent substrate 405. ), A thin film transistor (TFT) including a source electrode 420 and a drain electrode 430, a first light blocking pattern 413, and the thin film transistor (TFT) while covering a portion of the drain electrode 430. A passivation layer 440 to be exposed and an organic insulating layer 444 formed on the passivation layer 440 while being exposed while exposing a portion of the drain electrode 430 are included. The first light blocking pattern 413 may be formed in a floating state when the gate electrode 410 is formed, and a plurality of grooves and grooves may be formed on the surface of the organic insulating layer 444 to increase reflection efficiency.

The thin film transistor substrate 400 covers a pixel electrode 450 connected to the drain electrode 430 through a contact hole 441 by opening a portion of the thin film transistor substrate 444 and the entire thin film transistor TFT. And an interlayer insulating film 452 and a reflecting plate 460 formed on the interlayer insulating film 452, and define a region in which the reflecting plate 460 is formed as a reflecting region, and define a region in which the reflecting plate 460 is not formed. 445).

The pixel electrode 450 is a kind of transmission electrode that transmits light, and indium tin oxide (ITO), tin oxide (TO), or indium zinc oxide (IZO) is used. Although not shown, before the pixel electrode 450 is formed, a separate capacitor wiring is formed in a region spaced apart from the thin film transistor TFT by a predetermined distance, preferably, a lower region of the reflector 460 to form the capacitor wiring and the pixel. The electrode 450 is defined as a storage capacitor Cst.

Here, the reflective plate 460 is formed in a region corresponding to the reflective region among the upper regions of the interlayer insulating film 452, and is transmitted in a partial region of the edge of the reflective region, that is, a region of the edge in contact with the transmissive region. It extends by a certain length (I) to the area. In the drawing, although the reflective plate 460 and the pixel electrode 450 are separated by the interlayer insulating layer 452 and electrically insulated from each other, a portion of the interlayer insulating layer 452 is removed to expose the pixel electrode 450. In addition, the pixel electrode 450 and the reflector 460 may be connected. Here, the interlayer insulating film 452 to be removed is a region corresponding to the transmission region.

On the other hand, the color filter substrate 200 is omitted because it is the same as the color filter substrate described with reference to FIG.

The liquid crystal layer 300 is formed between the thin film transistor substrate 400 and the color filter substrate 200, so that the power applied to the pixel electrode 450 of the thin film transistor substrate 400 and the common electrode layer of the color filter substrate 200 ( Natural light passing through the color filter substrate 200 may be transmitted or artificial light passing through the transmission window 445 may be transmitted in response to a power applied to the power supply. In this case, the liquid crystal layer 300 includes a liquid crystal layer corresponding to an area in which the contact hole 441 is formed, a liquid crystal layer corresponding to an area in which the contact hole 441 is not formed, and a liquid crystal layer corresponding to the transmission area. Each liquid crystal layer may be distinguished from each other, and each liquid crystal layer may have a different cell gap. Here, the cell gap of the liquid crystal layer corresponding to the region where the contact hole 441 is formed is defined as d1, and the cell gap of the liquid crystal layer corresponding to the region where the contact hole 441 is not formed is defined as d2 and corresponds to the transmission window 445. When defining the cell gap of the liquid crystal layer to be d3, it is preferable to satisfy the condition of d2 <

In particular, when the anisotropic refractive index of the liquid crystal molecules constituting the liquid crystal layer 300 is Δn and the cell gap is d, the organic insulating layer 444 is not present in the region where the contact hole 441 is formed. Because it is formed, the liquid crystal layer 300 has an optical characteristic of Δnd1. Since the organic insulating layer having a thickness higher than that of the organic insulating layer formed in the region where the contact hole 441 is formed is formed in the region where the contact hole 441 is not formed, the liquid crystal layer 300 has an optical characteristic of Δnd 2. Meanwhile, since the organic insulating layer having the lowest thickness is formed in the transmission region, the liquid crystal layer 300 corresponding to the transmission region has a characteristic of Δnd3.

In addition, the liquid crystal molecules included in the liquid crystal layer 300 are homogeneous aligned to design a twist angle of 0 degrees. Assuming that the first alignment layer (not shown) provided on the thin film transistor substrate 100 is rubbed in the first direction to design the twist angle to 0 degree, the second alignment layer provided on the color filter substrate 200 ( Not shown) rubbing in a second direction opposite to the first direction. At this time, one edge of the reflective plate 460 that is close to the thin film transistor TFT extends to the transmission window 445. Of course, if the first alignment layer provided on the thin film transistor substrate 400 is rubbed in the second direction, the second alignment layer provided on the color filter substrate 200 is rubbed in the first direction, and the edge of the reflecting plate 460 may be formed. An edge far from the thin film transistor (TFT) will extend into the region of the transmission window 445.

In the above description, a method of applying power between both ends of the liquid crystal layer 300 by forming a pixel electrode 450 on the thin film transistor substrate 400 and a common electrode (not shown) on the color filter substrate 200 has been described. When the common electrode layer is not formed on the substrate 200, the same applies to a liquid crystal display device employing a CE (Coplanar Electrode) mode such as, for example, an IPS (In-Plane Switching) mode or a FFS (Fringe Field Switching) mode. Can be adopted.

9 is a plan view illustrating a multi-cell gap reflection-transmissive liquid crystal display device according to still another exemplary embodiment of the present invention. In particular, a thin film transistor substrate for a reflection-transmissive liquid crystal display device having a bottom ITO structure will be described.

9, a thin film transistor substrate according to another embodiment of the present invention may include a first light blocking pattern 513 and a data line formed when the gate line 509, the data line 519, and the gate line 509 are formed. A second light blocking pattern 522, a thin film transistor (TFT), a pixel electrode 542, and a reflective plate 560 defining a reflective region and a transmission window 545 are formed.

The gate wiring 509 extends in the horizontal direction on the substrate (not shown) and is arranged in the vertical direction, and the data wiring 519 extends in the vertical direction and is arranged in the horizontal direction.

The first light blocking pattern 513 is formed when the gate line 509 is formed. The first light blocking pattern 513 extends in a vertical direction so that a portion of the first light blocking pattern 513 overlaps with the data line 519 to be formed thereon. . The first light blocking pattern 513 blocks afterimages and light leakage generated through the left vertical side of the transmission window 545 when the rubbing direction is approximately left to right when viewed in a plan view.

The second light blocking pattern 522 is formed when the data line 519 is formed. The second light blocking pattern 522 extends in a horizontal direction so that a portion of the second light blocking pattern 522 overlaps with the gate line 509 formed at the bottom when viewed on a plane. The second light blocking pattern 522 blocks afterimages and light leakage that occur through the upper horizontal side of the transmission window 545 when the rubbing direction is directed from the lower side to the upper direction when viewed in a plan view.

The thin film transistor TFT is formed in each region defined by the gate wiring 509 adjacent to each other and the data wiring 519 adjacent to each other, and extends from the gate electrode 510 and the data wiring extending from the gate wiring 509. A source electrode 520 extending from 519 and a drain electrode 530 spaced apart from the source electrode 520.

The pixel electrode 542 is formed in each region defined by the gate line 509 adjacent to each other and the data line 519 adjacent to each other, and is connected to the drain electrode 530 through the contact hole 541.

The reflective plate 560 is formed on the pixel electrode 542 to define a reflection area for reflecting natural light and a transmission area or transmission window 545 for transmitting artificial light, and extend from a predetermined area of the edge of the reflection area to the transmission area. And is connected to the pixel electrode 542.

The reflective plate 560 is formed in a region corresponding to the reflective region, and extends into the transmission window 545 in consideration of the rubbing direction of the alignment layer (not shown) and is connected to the pixel electrode 542 provided below. In particular, in the drawing, the transmission window 545 is formed at a predetermined area of the edge of the reflection area adjacent to the lower side and the right side of the transmission window 545 on the assumption that the alignment film is rubbed in the 10 o'clock direction when viewed from an observer's point of view. As illustrated in FIG. 1, the pixel electrode 542 is extended to be connected to the pixel electrode 542 provided below.

Although not shown in the drawings, when the independent wiring method is employed, the lower metal formed in the area covered by the reflector 560 when the gate wiring 509 is formed and the lower metal when the data wiring 519 is formed. It is preferable to define the storage capacitor Cst through the formed upper metal. The storage capacitor Cst and the pixel electrode 542 are connected through a predetermined contact hole to charge the charge provided from the drain electrode via the pixel electrode 542, and discharge the charged charge for one frame to display the display state. Keep it.

10 is a cross-sectional view taken along the line C-C 'of FIG. 9 described above. In particular, a bottom ITO liquid crystal display device is shown.

Referring to FIG. 10, a reflection-transmissive liquid crystal display according to another exemplary embodiment of the present invention may include a thin film transistor substrate 500, a color filter substrate 200, and a thin film transistor substrate 500 and a color filter substrate 200. The formed liquid crystal layer 300 is included. Here, illustration of λ / 4 phase retardation films and polarizing plates disposed on the color filter substrate 200 or below the thin film transistor substrate 500 will be omitted.

The thin film transistor substrate 500 may include the gate electrode 510 formed on the transparent substrate 505, the gate electrode 510, the gate insulating layer 512 formed on the transparent substrate 505, the semiconductor layer 514, and the ohmic contact layer 516. ), A thin film transistor (TFT) including a source electrode 520 and a drain electrode 530, a first light blocking pattern 513, and the thin film transistor (TFT) to cover a portion of the drain electrode 530. Passivation layer 540 to be exposed. The first light blocking pattern 513 is preferably formed in a floating state when the gate electrode 510 is formed.

The thin film transistor substrate 500 is connected to the drain electrode 530 exposed by the passivation layer 540, and includes a pixel electrode 542 formed up to a region corresponding to the transmissive region, and a passivation layer 540 corresponding to the reflective region. And an organic insulating layer 544 formed on the thin film. It is preferable to form a plurality of grooves and grooves on the surface of the organic insulating layer 544 to increase reflection efficiency.

The thin film transistor substrate 500 includes a reflector plate 560 formed on the organic insulating layer 544 while covering the entire TFT, and defines a region where the reflector plate 560 is formed as a reflecting area, and reflector plate 560. The unformed area is defined as the transmission window 545.

Although not shown, before the pixel electrode 542 is formed, a separate capacitor wiring is formed in an area spaced apart from the thin film transistor TFT by a predetermined distance, preferably, a lower area of the reflector 560 to form the capacitor wiring and the pixel. The electrode 542 is defined as a storage capacitor Cst.

The reflecting plate 560 is formed in the upper region of the organic insulating layer 544 and extends from the partial region of the edge of the reflective region, that is, the partial region of the edge in contact with the transmissive region by the predetermined length (I). It is formed.

Meanwhile, the liquid crystal layer 300 is formed between the thin film transistor substrate 500 and the color filter substrate 200, so that the power applied to the pixel electrode 542 of the thin film transistor substrate 500 and the color filter substrate 200 are common to each other. In response to the power applied to the electrode layer (not shown), natural light passing through the color filter substrate 200 may be transmitted or artificial light passing through the transmission window 545 may be transmitted. In this case, the liquid crystal layer 300 may be classified into a liquid crystal layer corresponding to the reflective region and a liquid crystal layer corresponding to the transmission window 545, and each liquid crystal layer may have a different cell gap. The cell gap of the liquid crystal layer corresponding to the reflective region is d4, and the cell gap of the liquid crystal layer corresponding to the transmission window 545 is d5, and has the optical characteristics of the different liquid crystal layer.

11 is a block diagram of a single cell gap reflective transmission liquid crystal display device according to the present invention. Referring to FIG. 11, the source driver circuit 700 inputs an RGBW digital data signal to provide an analog data signal to data lines of the liquid crystal panel 600. The gate driving circuit 800 sequentially provides gate driving signals to gate lines of the liquid crystal panel 600.

The source driver circuit 700 includes a shift register 710, a data register 720, a data latch 730, a digital-to-analog converter 740, an output buffer 750, a selection switch 760, and a first gamma correction reference voltage. The generator 770 includes a second gamma correction reference voltage generator 780 and a mode selector 790. The shift register 710 sequentially inputs RGBW four-color data signals in synchronization with a clock signal and outputs one line of data signals in parallel. The data register 720 stores parallel data provided from the shift register 710 and provides data to the level shifter 730 in response to a timing signal. The level shifter 730 shifts the level of the data signal to provide the digital analog converter 740 with data signals having a predetermined level. The digital-to-analog converter 740 inputs the selected first or second gamma correction reference voltage signal through the selection switch 760 and generates an analog signal corresponding to the data signal using the input gamma correction reference voltage signal.

The first gamma correction reference voltage generator 770 generates a gamma correction reference voltage corresponding to the reflection mode, and the second gamma correction reference voltage generator 780 generates a gamma correction reference voltage corresponding to the transmission mode.

The first gamma correction reference voltage generator 770 is set to generate a reference voltage for compensating the gamma characteristics of the liquid crystal panel in the reflection mode, and the second gamma correction reference voltage generator 780 is configured to generate the reference voltage of the liquid crystal panel in the transmission mode. It is set to generate a reference voltage to compensate the gamma characteristic.

The mode selector 790 switches and controls the selection switch 760 in response to the reflection mode and the transmission mode.

Accordingly, in the single cell gap four-color semi-transmissive liquid crystal display of the present invention, display differences between the two modes can be minimized by compensating for different gamma characteristics in response to the reflection mode or the transmission mode.

12 is a plan view of a single cell gap high brightness transflective liquid crystal display according to the present invention.

Referring to FIG. 12, a pixel region represented by the pixel electrode 1311 is formed in an area where an upper portion of the thin film transistor, the gate wiring 1301, and the data wiring 1305c intersect, and the data wiring 1305c is formed inside the pixel region. ) And a transmission region 1340 having a constant shape in the direction of the reflection region is formed.

The transmission region 1340 may have a shape of a closed curve including a rectangle, a square, a polygon, and a protrusion.

In addition, a storage electrode 1341 is formed in the reflective region to store a predetermined signal. Here, the storage electrode 1341 may be formed in addition to the reflective region.

       A reflective electrode 1312 is formed in the reflective region, and the reflective electrode 1312 is partially stacked with the data line 1305c. In addition, the reflective electrode 1312 is formed at the boundary of the transmission region 1340.

       Here, the reflective electrode 1312 is not shorted to the gate line 1301 and the data line 1305c.

13 is a cross-sectional view taken along the cutting lines of D-D ′ and E-E ′ of FIG. 12.

      Referring to DD ′, a cross-sectional view of the liquid crystal display device having the white window is provided with a blocking film 1302 formed on the first substrate 1300 and a channel layer 1303b formed of a semiconductor layer on the blocking film 1302. ) Is formed, and the source region 1303a and the drain region 1303b, which are activated by introducing external ions into the semiconductor layer, are formed on the left and right sides thereof.

       A gate insulating film 1304a formed of an oxide is formed on the channel layer 1303b, and an interlayer insulating film 1308 is formed on the entire surface including the source region 1303a and the drain region 1303b.

       The data line 1305c is formed at the same time as the source electrode 1305a and the drain electrode 1305b on the interlayer insulating film 1308, and the storage electrode 1341 is formed at the same time as or different from the data line 1305c. Form.

       An embossed organic insulating layer 1310a is formed on the data line 1305c and the storage electrode 1341, and a pixel electrode 1311 is formed on the entire surface thereof. In addition, a reflective electrode 1312 is formed on a portion of the upper portion of the pixel electrode 1311 to distinguish the reflective region from the transparent region.

       A color filter layer 1352 having a colored layer of red (R), green (G), blue (B), and white (W) is formed on the second substrate. Edges of the colored layers adjacent to each other overlap each other to form a light shielding layer 1351.

       An overcoat layer 1353 is formed on the color filter layer 1352 for planarization, and a common electrode 1354 is formed on the overcoat layer 1353.

Referring to the cross-section of EE ′, the cross-sectional view of the reflective transmissive liquid crystal display device shows that a blocking film 1302 is formed on the first substrate 1300 and a channel layer 1303b formed of a semiconductor layer on the blocking film 1302. Is formed, and a gate insulating film 1304a is formed thereon. A gate electrode 1301a is formed on the gate insulating layer 1304a.

       The gate insulating film 1304a is formed in the gate region into which the scan signal is introduced, and the gate wiring 1301 is formed thereon.

An interlayer insulating film 1308 is formed on the gate electrode 1301a and the gate wiring 1301, and a storage electrode 1341 is formed on the interlayer insulating film 1308, and an embossed organic insulating film is formed on the entire surface thereof. 1310a is formed.

A pixel electrode 1311 is formed on the organic insulating layer 1310a, and a reflective electrode 1312 is formed on the pixel electrode 1311 to distinguish the reflective region. The reflective electrode 1312 is formed to expose the gate wiring 1301.

       The second substrate 1350 is formed with a light blocking layer 1351 of a black matrix that blocks light leakage from the gate wiring 1301, and a color filter layer including red, green, blue, and white colored layers therebetween. 1352 is formed.

       An overcoat layer 1353 is formed on the color filter layer 1351 for planarization, and a common electrode 1354 is formed on the overcoat layer 1353.

14A to 14F are cross-sectional views of the method of manufacturing the transflective liquid crystal display shown in FIG.

Referring to DD ′ of FIG. 14A, the first substrate 1300 is cleaned, and a silicon nitride (SiNx) or silicon oxide (SiOx) is deposited on the entire surface of the first substrate 1300 by chemical vapor deposition (CVD). 1302 is formed. A semiconductor layer is formed on the blocking film 1302. The semiconductor layer may be formed of IDLTPS-Ion Drived Low Temperature Poly Silicon or amorphous silicon. After the photoresist is applied, the first mask is installed, exposed, developed, wet etched and the photoresist removed, the patterned semiconductor layer 1303 is formed.

Referring to EE ′ of FIG. 14A, the first substrate 1300 is cleaned, and a silicon nitride (SiNx) or silicon oxide (SiOx) is deposited on the entire surface of the first substrate 1300 by chemical vapor deposition (CVD). 1302 is formed. A semiconductor layer is formed on the blocking layer 1302 and is patterned using a first mask to form a channel layer 1303b as a semiconductor layer.

Referring to DD ′ of FIG. 14B, a gate insulating film 1304 of silicon nitride (SiNx) or silicon oxide (SiOx) is formed on the entire surface including the semiconductor layer 1303, and a low resistance metal such as chromium is sputtered thereon. After depositing by a method, applying a photoresist on the upper surface, installing a second mask, exposing and developing, wet etching and peeling off the photoresist, a gate electrode 1301a is formed.

Referring to EE ′ of FIG. 14B, a gate insulating film 1304 of silicon nitride (SiNx) or silicon oxide (SiOx) is formed on the entire surface including the channel layer 1303b and a low resistance metal such as chromium is sputtered thereon. The gate wiring 1301 and the gate electrode 1301a are formed by vapor deposition and patterning using a second mask.

Referring to DD ′ of FIG. 14C, the gate insulating layer 1304 is patterned using the gate electrode 1301 a as a mask, and at the same time, source ion (or photoelectrons) is introduced into the semiconductor layers to the left and right of the gate electrode 1301 a. 1303a and a drain region 1303c are formed.

Referring to E-E 'of FIG. 14C, the gate insulating film 1304 is patterned using the gate electrode 1301a and the gate wiring 1301 as a mask.

Referring to DD ′ of FIG. 14D, chemical vapor deposition (CVD) is performed on silicon nitride (SiNx) or silicon oxide (SiOx) on the entire surface including the gate electrode 1301a, the source region 1303a, and the drain region 1303b. To form an interlayer insulating film 1308, apply a photoresist on top of it, install a third mask, expose and develop, wet etch, and peel off the photoresist to form a low resistance metal. The source electrode 1305a, the drain electrode 1305b, the data wiring 1305c, and the storage electrode 1341 are formed at each time at the same time or at different times.

Referring to EE ′ of FIG. 14D, an interlayer insulating film 1308 is formed by depositing silicon nitride (SiNx) or silicon oxide (SiOx) on the entire surface including the gate electrode 1301a and the gate wiring 1301 by chemical vapor deposition (CVD). ), And then a low resistance metal is deposited on the interlayer insulating film 1308 by a sputtering method. A third mask is provided here, exposed to light, developed, wet-etched, the photoresist is peeled off, the gate electrode 1301a and the gate wiring 1301 are exposed, and simultaneously or different at each position. The storage electrode 1341 is formed in time.

Referring to DD ′ of FIG. 14E, an organic insulating film of acrylate or epoxy is coated on the entire surface including the source electrode 1305a, the drain electrode 1305b, the data line 1305c, and the storage electrode 1341. After installing and exposing a fourth mask, developing, and wet etching, the photoresist is peeled off to form a patterned organic insulating film 1310a.

A pixel electrode 1311 is formed on the patterned organic insulating layer 1310a, a reflective metal formed of aluminum or an aluminum alloy is deposited on the pixel electrode 1311 by a sputtering method, and a fifth mask is installed and exposed. After the development, wet etching is performed, and the photoresist is peeled off to form the reflective electrode 1312.

The reflective electrode 1312 is formed so as not to be shorted on the data line 1305c.

The transmission region formed by the pixel electrode 1311 is formed to be variable according to the intensity of light. The storage electrode 1341 may be formed under the reflective electrode 1341 to process information, or may be exposed to an optical signal in the same manner as the data line 1305c. In this case, the reflective electrode 1312 of the storage electrode 1311 is formed so as not to be shorted to the storage electrode 1311.

Referring to EE ′ of FIG. 14E, an organic insulating film of acrylate or epoxy is coated on the entire surface including the gate electrode 1301a, the gate electrode 1301, and the storage electrode 1342, and a fourth mask is installed and exposed. After the development, the wafer is wet etched, the photoresist is peeled off, and the patterned organic insulating layer 1310a is formed.

A pixel electrode 1311 is formed on the patterned organic insulating layer 1310a, a reflective metal formed of aluminum or an aluminum alloy is deposited on the pixel electrode 1311 by a sputtering method, a fifth mask is installed, exposed, and developed. After that, wet etching is performed and the photoresist is peeled off to form the reflective electrode 1312.

The reflective electrode 1312 is formed so as not to be shorted on the gate line 1301.

The transmission region formed by the pixel electrode 1311 is formed to be variable according to the intensity of light. The storage electrode 1341 may be formed under the reflective electrode 1341 to process information, and may be exposed to an optical signal in the same manner as the gate wiring 1301. In this case, the reflective electrode 1312 of the storage electrode 1311 is formed so as not to be shorted to the storage electrode 1311.

Referring to D-D ′ of FIG. 14F, a color filter layer 1352 having a colored layer of red (R), green (G), blue (B), and white (W) is formed on the second substrate. An overcoat layer 1353 is formed on the color filter layer 1352 for planarization, and a common electrode 1354 is formed on the overcoat layer 1353.

Referring to E-E 'of FIG. 14F, a color filter layer 1352 having a colored layer of red (R), green (G), blue (B), and white (W) is disposed on the second substrate. An overcoat layer 1353 is formed on the color filter layer 1352 for planarization, and a common electrode 1354 is formed on the overcoat layer 1353.

In the present invention, since the display difference between the reflection mode and the transmission mode can be adjusted by the area ratio of the white colored layer, the color filter layer 1352 can be formed flat, so that the overcoding layer can be removed as necessary.

Although described above with reference to the embodiments, those skilled in the art can be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below. I can understand.

As described above, in the present invention, the display difference between the reflection mode and the transmission mode is optimized by adjusting the area ratio between the transmission area and the reflection area in the white pixel. Therefore, the display difference can be effectively reduced while improving the luminance of the color pixels.

In addition, in the present invention, when the four-color color filter is formed, the coating process of the color material is added once compared to the three-color color filter. This is easy, and the overcoating layer can be removed as needed, which simplifies the manufacturing process compared to existing methods.

1 is a view for explaining the operation of the general transflective liquid crystal display device.

2 to 4 are layout views of RGBW showing a relationship between a color filter and a reflection and transmission region of the high brightness transflective liquid crystal display according to the present invention.

5 is a plan view illustrating a unit pixel of an exemplary embodiment of a dual cell gap high brightness semi-transmissive liquid crystal display according to the present invention.

FIG. 6 is a cross-sectional view taken along a cutting line of AA ′ of FIG. 5.

FIG. 7 is a plan view illustrating a unit pixel of another exemplary embodiment of a dual cell gap high brightness semi-transmissive liquid crystal display according to the present invention.

FIG. 8 is a cross-sectional view taken along the line BB ′ of FIG. 7.

FIG. 9 is a plan view illustrating a unit pixel of another embodiment of a dual cell gap high brightness semi-transmissive liquid crystal display according to the present invention.

FIG. 10 is a cross-sectional view taken along line C-C ′ of FIG. 9.

11 is a block diagram of a single cell gap high brightness semi-transmissive liquid crystal display according to the present invention.

12 is a plan view of a single cell gap high brightness transflective liquid crystal display according to the present invention.

FIG. 13 is a cross-sectional view taken along cut lines of D-D ′ and E-E ′ of FIG. 12.

14A to 14F are cross-sectional views illustrating a method of manufacturing the transflective liquid crystal display device illustrated in FIG. 13.

<Description of the symbols for the main parts of the drawings>

UPX1 ~ UPX3: unit pixel RR: reflection area

TR: Transmission Area CPX: Color Pixel

100, 400: array substrate 200: color filter substrate

210: colored layer 300: liquid crystal layer

409, 509: Gate lines 413, 422, 513, 522: Light blocking pattern

419, 519: Source lines 445, 545: Transmission window

450, 542: pixel electrode 460, 560: reflector plate

600: liquid crystal panel 700: source driving circuit

800: gate driving circuit

1300: first substrate 1301: gate wiring

1301a: gate electrode 1302: blocking film

1303a: source region 1303b: channel layer

1303c: drain region 1304, 1304a: gate insulating film

1305a: source electrode 1305b: drain electrode

1305c: Data wiring 1308: Interlayer insulating film

1310a: organic insulating film 1311: pixel electrode

1312: reflective electrode 1340: transmission region

1350: Second substrate 1351: Light blocking layer

1352: color filter layer 1353: overcoat layer

1354 common electrode 1370 liquid crystal layer

Claims (6)

       A color filter constituting one color pixel by combining at least three or more colored layers each colored with different chromatic colors and one colored layer colored white; A reflective layer formed corresponding to a partial region of each of the colored layers; A transmissive layer formed corresponding to the remaining partial region of each colored layer; And a liquid crystal layer injected between the reflective layer and the transmissive layer and the corresponding colored layer.        The method of claim 1, wherein the area ratio of the reflective layer and the transparent layer corresponding to the white colored layer is A high-brightness reflective transmissive liquid crystal display device characterized by an optimized area ratio for minimizing the difference between the transmissive display and the reflective display of one color pixel.        The liquid crystal display of claim 2, wherein the at least three or more colored layers having different chromatic colors are a red layer, a green layer, and a blue layer.        The high brightness reflective transmissive liquid crystal display device according to claim 1, wherein an interval between the colored layer and the reflective layer is smaller than an interval between the colored layer and the transmissive layer.        2. The liquid crystal driving voltage according to claim 1, wherein an interval between the colored layer and the corresponding transmissive layer and the reflective layer is the same, and the liquid crystal driving voltage between the colored layer and the corresponding transmissive layer and the liquid crystal driving voltage between the colored layer and the reflective layer are corresponding. And the difference is optimized by a voltage difference which minimizes the difference between the transmissive display and the reflective display of one color pixel.        The method of claim 5, wherein the first gamma correction reference voltage of the reflection mode and the second gamma correction reference voltage of the transmission mode are set differently to minimize the display difference between the transmission mode and the reflection mode. A high brightness reflective transmission liquid crystal display device, characterized in that the second gamma correction reference voltage is selected.