KR20050116174A - Transflective type array substrate, and liquid crystal display having the same - Google Patents

Abstract

A reflection-transmissive array substrate for preventing adjacent pixel defects and a liquid crystal display device having the same are disclosed. The first pixel portion has a first transmission portion that transmits the second light and a first reflection portion that reflects the first light. The second pixel portion is adjacent to the first pixel portion, and has a second transmission portion that transmits second light adjacent to the first reflection portion and a second reflection portion that reflects natural light. Accordingly, by forming the reflecting plates in the adjacent pixels shifted from each other, the defective adjacent pixels due to the reflecting plate pattern defects can be prevented.

Description

Reflective-transmissive array substrate and liquid crystal display having the same {TRANSFLECTIVE TYPE ARRAY SUBSTRATE, AND LIQUID CRYSTAL DISPLAY HAVING THE SAME}

The present invention relates to a reflective-transmissive array substrate and a liquid crystal display having the same, and more particularly, to a reflective-transmissive array substrate and a liquid crystal display having the same to prevent adjacent pixel defects.

In general, since a reflection type LCD uses light incident from the outside, the display becomes dark due to a decrease in the amount of light in a dark place, so that the displayed image cannot be properly viewed.

In addition, since a transmission type LCD uses a light source inside a device such as a backlight, it is possible to recognize an image displayed regardless of a bright or dark place, but the power consumption is increased by the amount of the light source. There is a disadvantage that it is not suitable for a portable display device or the like operated by a battery.

In order to solve these shortcomings, development of a reflective-transmissive liquid crystal display (Transflective Type LCD or Reflection and Penetration type LCD) using the above-described reflective liquid crystal display and a transmissive liquid crystal display is emerging.

1 is a diagram illustrating an array substrate generally used in a reflection-transmissive liquid crystal display device. As shown, it has a plurality of pixels defined by the scan lines G1, G2,... And the data lines D1, D2, .. where the light from the backlight in the liquid crystal display is provided. It has a transmission part 115 which permeate | transmits, and the reflection part 116 which reflects the light incident from the exterior. (Since it is a conventional technology, it was not divided into the first light and the second light.)

FIG. 2 is a schematic cross-sectional view of the array substrate illustrated in FIG. 1 taken along a cutting line A-A '. Referring to FIG. 2, data lines D1, D2, and D3 are formed on the substrate 110, and an organic layer 114 having an uneven pattern is formed on the data lines D1, D2 and D3. Concave-convex patterns are formed on the surface of the organic layer 114, and transparent electrodes 115 and reflecting plates 116 are formed on the transmissive and reflecting portions corresponding to the respective pixels.

In general, the reflective plate 116 is formed on the transparent electrode 115 to correspond to the reflective region of the pixel portion P. FIG. At this time, the reflective plate 116 is spaced apart from the transparent electrode 115, as shown by the 'I' portion shown by different physical properties between the reflective plate 116 and the transparent electrode 115 formed thereunder. do. Due to the defective pattern of the reflecting plate 116, a phenomenon occurs that is shorted with the reflecting plate 116 'in the adjacent pixel, causing problems such as deterioration of image quality.

Accordingly, the technical problem of the present invention is to solve such a conventional problem, and an object of the present invention is to provide a reflection-transmissive array substrate that prevents adjacent pixel defects caused by defective reflector patterns.

Another object of the present invention is to provide a liquid crystal display device having the above-mentioned reflection-transmissive array substrate.

A reflection-transmissive array substrate according to an embodiment for realizing the object of the present invention described above includes a first pixel portion and a second pixel portion adjacent to the first pixel portion. The first pixel portion includes a first transmission portion that transmits first light and a first reflection portion that reflects second light. The second pixel portion is adjacent to the first pixel portion, and has a second transmission portion that transmits the second light adjacent to the first reflection portion and a second reflection portion that reflects the first light.

The liquid crystal display according to the exemplary embodiment for realizing another object of the present invention includes an array substrate, a liquid crystal layer, and a color filter substrate. The array substrate includes transmissive portions provided in adjacent pixel portions, and reflective portions extending from each of the transmissive portions within the pixel portion, and alternately arranged pixel portions adjacent to each other. The color filter substrate includes a color filter corresponding to each of the pixel units, and accommodates the liquid crystal layer through coalescence with the array substrate.

According to such a reflection-transmissive array substrate and a liquid crystal display device having the same, adjacent pixel defects due to a defective reflection plate pattern can be prevented by displacing the reflection plates in adjacent pixels.

Hereinafter, with reference to the accompanying drawings, it will be described in detail the present invention.

3 illustrates a reflective-transmissive array substrate in accordance with one embodiment of the present invention. The reflection-transmissive array substrate has a structure for driving n x m pixel units through n data lines and m scan lines. Hereinafter, the present invention will be described in more detail with reference to the adjacent first pixel portion and the second pixel portion.

The first switching element receives a scan signal through a first scan line G1 extending in a horizontal direction on the array substrate and a data signal through a first data line D1 extending in a vertical direction. Has 310.

The first switching element 310 may include a gate electrode 312 extending from the first scan line G1, a source electrode 314 extending from the first data line D1, and the source electrode 314. The drain electrode 316 is spaced apart from the predetermined distance from the drain electrode 316 and is electrically connected to the first pixel electrode 317. Here, the illustration of the active layer or the semiconductor layer formed on the active layer is omitted.

The first pixel electrode 317 has a first reflecting portion R1 having a first reflecting plate 319 reflecting first light and a first transmitting portion T1 having no first reflecting plate 319 formed thereon. The second light is transmitted by the first transmission portion T1. Here, the first light is light incident on the reflector, for example, light emitted from natural light and front lights. In addition, the second light is light incident on the transmission part, for example, light emitted from the backlight.

Meanwhile, the second pixel unit adjacent to the first pixel unit has a second switching element 330 that receives a scan signal through the first scan line G1 and receives a data signal through the second data line D2. .

The second switching element 330 includes a gate electrode 322 extending from the first scan line G1, a source electrode 334 extending from the second data line D2, and the source electrode 334. The drain electrode 336 is spaced apart from the predetermined distance from the drain electrode 336 and is electrically connected to the second pixel electrode 337. Here, the illustration of the active layer or the semiconductor layer formed on the active layer is omitted.

The second pixel electrode 337 has a second reflecting portion R2 having a second reflecting plate 339 reflecting the first light and a second transmitting portion T2 having no second reflecting plate 339 formed thereon. The second light is transmitted by the second transmission part T2.

Here, the position of the second reflecting plate 339 formed on the second pixel electrode 337 of the second pixel portion is formed so as not to be adjacent to the position of the second reflecting plate 319 in the first pixel portion.

In other words, the reflection parts in the plurality of pixel parts are implemented to be adjacent to each other with the transmission parts in the adjacent pixel parts. This minimizes pixel defects due to pattern defects between reflecting plates in adjacent pixel portions.

As described above, the first and second switching elements 310 and 330 of the first and second pixel units are formed in one direction based on the first scan line G1. In such a structure, when the reflecting portions in the adjacent pixel portions are disposed to be offset, the first reflecting portion T1 of the first pixel portion is formed on the upper portion where the first switching element 310 is not formed, and the second reflecting portion of the second pixel portion is formed. The reflector T2 is formed at a lower portion of the second switching element 330. That is, a switching element is formed in the transmissive part in the pixel part.

In view of this, in order to improve the luminance characteristic according to the aperture ratio of the reflection-transmissive array substrate, the color filter layers R, G, and B of the color filter substrate disposed on the reflection-transmission array substrate may be adjusted. That is, green (G) is most sensitive to the three primary colors R, G, and B of the light, and green is the most important variable that influences luminance in the liquid crystal display device. It can be adjusted to the maximum.

Therefore, the R and B color filter layers are disposed corresponding to the first pixel portion P1 having the transmissive portion formed on the switching element, and the G color filter layer is disposed corresponding to the second pixel portion formed with the reflecting portion on the switching element, thereby reducing the aperture ratio. The luminance characteristic can be improved.

4 is a cross-sectional view taken along the cutting line B-B ′ of the first pixel portion and the second pixel portion of the array substrate of FIG. 3.

Referring to FIG. 4, a first gate electrode 312, a first gate insulating layer 313 formed on the first gate electrode 312, and a first active layer may be formed in the first pixel portion P1 on the substrate 301. A first switching element TFT1 including a 304, a first semiconductor layer 305, a first source electrode 314, and a first drain electrode 316 is formed. A second gate electrode 332, a second gate insulating layer 333, a second active layer 304, and a second gate electrode 332 formed on the second gate electrode 332 are formed on the second pixel portion P2 on the substrate 301. The second switching element TFT2 including the semiconductor layer 305, the second source electrode 334, and the second drain electrode 336 is formed.

A portion of the first drain electrode 316 and a portion of the second drain electrode 336 cover the first switching element TFT1 and the second switching element TFT2, respectively, and the first contact hole 322 and the second contact, respectively. An organic passivation layer 321 formed to be exposed through the hole 324, and an organic part exposing a portion of the first drain electrode 316 and a portion of the second drain electrode 336 while covering the passivation layer 321. A film 325 is formed. A pixel electrode is formed on the organic layer 325, and in general, the pixel electrode may be formed over the entire pixel area or only in an area corresponding to the transmissive part.

Here, the first pixel electrode 317 and the second pixel electrode 337 are generally formed on the organic layer 325 in the first pixel portion P1 and the second pixel portion P2 corresponding to each pixel region. do.

The first pixel electrode 317 is connected to the first drain electrode 316 of the first switching element TFT1 to form the first transmission portion T1 of the first pixel portion P1. The second pixel electrode 337 is formed to be connected to the second drain electrode 336 of the second switching element TFT2, and the reflective plate 339 is formed on the second pixel electrode 337 to form a second pixel. The second reflecting portion R2 of the portion P2 is formed. Here, the first and second pixel electrodes 317 and 337 may be light transmissive electrodes, and indium tin oxide (ITO) and indium zinc oxide (IZO) materials may be used, and the reflective plate may be used. Reference numeral 283 is a kind of reflective electrode that reflects light, and preferably aluminum, aluminum-neodymium alloy, or the like is used.

As the surface of the organic film 325 is uneven, the unevenness corresponding to the transmissive region acts as a kind of micro-transmissive lens to scatter the second light, and the unevenness corresponding to the reflective region causes the reflector 339 to be a micro-reflective lens. It is shown to scatter the first light by forming to operate. However, those skilled in the art may planarize the surface of the organic film described above.

3 and 4, the first transmission portion T1 of the first pixel portion P1 and the second reflection portion R2 of the second pixel portion P2 are adjacent to each other. In other words, the reflecting portion R1 of the first pixel portion P1 and the reflecting portion R2 of the second pixel portion P2 are formed to be offset from each other. Thereby, the pixel defect by the pattern defect of the reflecting plate between adjacent pixels can be prevented.

5 is a diagram for describing a liquid crystal display according to an exemplary embodiment of the present invention.

Referring to FIG. 5, the liquid crystal display according to the exemplary embodiment of the present invention includes an array substrate 300, a color filter substrate 400, and a liquid crystal layer 490.

The array substrate 300 includes transmissive portions provided in adjacent pixel portions, and reflective portions extending from each of the transmissive portions within the pixel portion and alternately arranged adjacent to each other. Since the array substrate 300 has been described with reference to FIG. 4, detailed description thereof will be omitted.

The color filter substrate 400 may include a black matrix layer 410, color filter layers 422 and 424, a planarization layer 430, and a common electrode layer 440. The liquid crystal may be integrated with the array substrate 300. Receives layer 490.

In detail, the black matrix layer 410 is formed on the transparent substrate 401 to prevent light leakage between pixels while defining each pixel area. The black matrix layer 410 may be formed to correspond to the data line, may be formed to correspond to the gate line, or may be formed to correspond to the data line and the gate line.

The color filter layers 422 and 424 may be formed to correspond to the pixel area defined as the black matrix layer 410, including R (red), G (Green), and B (Blue) color filter layers. For example, as illustrated, an R color filter layer 422 is formed in the first pixel portion P1, and a G color filter layer 424 is formed in the second pixel portion P2.

In addition, a portion of the color filter layer corresponding to the reflective part R2 of the array substrate 300 is removed to define a light hole. For example, as shown in the drawing, a part of the G color filter layer 424 corresponding to the reflecting portion R2 of the second pixel portion P2 is removed, so that the function of the light hole 424 transmits the white light provided from the bottom as it is. Do this.

The planarization layer 430 is formed on the color filter layer 420 to remove the step of the color filter layer 420 by the light hole 424, and the common electrode layer 440 is formed on the planarization layer 430. The voltage of a predetermined level supplied from the outside is supplied to the liquid crystal layer 490.

As such, by forming the light holes in the color filter layers corresponding to the reflecting portions, the difference in luminance between the transmitted light and the reflected light can be compensated for. That is, the first light incident on the reflective part R2 passes through the G color filter layer 424 twice, and the second light incident on the transmissive part T1 passes through the R color filter layer 422 once. Accordingly, the first light passes through the color filter layer several times by the reflector R2, thereby compensating for the decrease in luminance.

Figure 6 illustrates a reflective-transmissive array substrate according to another embodiment of the present invention.

Referring to FIG. 6, the reflection-transmissive array substrate has a structure having n / 2 data lines and 2m scan lines to drive n × m pixels. For example, the first pixel portion is driven by the first scan line G1 and the data line D2, and the second pixel portion is driven by the second scan line G2 and the data line D2.

The first pixel unit has a first switching element 510 through which a scan signal is input through the first scan line G1 and a data signal is input through the data line D2.

The first switching element 510 includes a first gate electrode 512 extending from the first scan line G1, a first source electrode 514 extending from the data line D2, and the first source. The first drain electrode 516 is spaced apart from the electrode 514 by a predetermined distance, and the first drain electrode 516 is electrically connected to the first pixel electrode 517.

The first reflecting plate 519 is formed on the first pixel electrode 517 corresponding to the region where the first switching element 510 is formed to form a first reflecting unit R1. In the regions other than the first reflecting portion R1, the first transmitting portion T1 transmitting the second light is formed.

The second pixel unit has a second switching element 530 through which a scan signal is input through a second scan line G2 and a data signal is input through the data line D2.

The second switching element 530 may include a second gate electrode 532 extending from the second scan line G2, a second source electrode 534 extending from the data line D2, and the second source. The second drain electrode 536 is spaced apart from the electrode 534 by a predetermined distance, and the second drain electrode 536 is electrically connected to the second pixel electrode 537.

A second reflector 539 is formed on the second pixel electrode 537 corresponding to the region where the second switching element 530 is formed to form a second reflector R2. In the regions other than the second reflecting portion R2, the second transmitting portion T2 transmitting the second light is formed.

As illustrated, the first switching element 510 is connected to the first scan line G1, and the second switching element 530 is connected to the second scan line G2. The first and second switching elements 510 and 530 formed in the second pixel portion are not adjacent to each other. In addition, the first and second reflecting portions R1 and R2 are also not adjacent to the first and second switching elements 510 and 530.

Accordingly, the reflection parts in the plurality of pixels may be offset from the reflection parts in the adjacent pixels, thereby solving the pixel failure due to the pattern defect of the reflecting plate. In addition, since the first and second switching elements 510 and 530 are formed in the first and second reflectors R1 and R2, the problem of the aperture ratio of the pixel does not occur.

Figure 7 shows a reflective-transmissive array substrate according to another embodiment of the present invention.

Referring to FIG. 7, the reflection-transmissive array substrate drives n x m pixels through n data lines and m scan lines, and the m scan lines are wired in the pixels.

The first pixel portion and the second pixel portion are driven by the first data line D1 and the second data line D2 based on the first scan line G1, and the first scan line G1 is driven by the first data line. And the second pixel portion respectively.

The first pixel unit has a first switching element 610 through which a scan signal is input through the first scan line G1 and a data signal is input through the first data line D1.

The first switching element 610 includes a first gate electrode 612 extending from the first scan line G1, a first source electrode 614 extending from the first data line D1, and the first gate electrode 612. The first drain electrode 616 is spaced apart from the source electrode 614 by a predetermined distance, and the first drain electrode 616 is electrically connected to the first pixel electrode 617.

The first reflecting plate 619 is formed on the first pixel electrode 617 corresponding to the region where the first switching element 610 is formed to form a first reflecting unit R1. In the regions other than the first reflecting portion R1, the first transmitting portion T1 transmitting the second light is formed.

The second pixel unit has a second switching element 630 through which a scan signal is input through the first scan line G1 and a data signal is input through the second data line D2.

The second switching element 630 may include a second gate electrode 632 extending from the first scan line G1, a second source electrode 634 extending from the second data line D2, and the second gate electrode 634. The second drain electrode 636 is spaced apart from the source electrode 634 by a predetermined distance, and the second drain electrode 636 is electrically connected to the second pixel electrode 637.

A second reflector 639 is formed on the second pixel electrode 637 corresponding to the region where the second switching element 630 is formed to form a second reflector R2. In the regions other than the second reflecting portion R2, the second transmitting portion T2 transmitting the second light is formed.

As illustrated, the first switching element 610 is formed above the first scan line G1, and the second switching element 630 is formed below the first scan line G2. The first and second switching elements 610 and 630 formed in the first pixel portion and the second pixel portion are not adjacent to each other. In addition, the first and second reflecting portions R1 and R2 are also not adjacent to the first and second switching elements 610 and 630.

Accordingly, the reflection parts in the plurality of pixels may be offset from the reflection parts in the adjacent pixels, thereby solving the pixel failure due to the pattern defect of the reflecting plate. Also. Since the first switching element 510 and the second switching element 530 are formed in the first reflecting portion R1 and the second reflecting portion R2, the problem of the aperture ratio of the pixel does not occur.

As described above in detail, according to the present invention, by forming the reflection parts in the adjacent pixels so as not to be adjacent to each other, it is possible to minimize the adjacent pixel defects caused by the reflection plate pattern defects.

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.

1 is a schematic diagram of a typical reflective-transmissive array substrate.

FIG. 2 is a schematic cross-sectional view of the array substrate illustrated in FIG. 1 taken along a cutting line A-A '.

3 is a schematic diagram of a reflective-transmissive array substrate in accordance with one embodiment of the present invention.

FIG. 4 is a cross-sectional view of the reflection-transmissive array substrate of FIG. 3 taken along a cutting line B-B '.

5 is a diagram for describing a liquid crystal display according to an exemplary embodiment of the present invention.

6 is a schematic diagram of a reflective-transmissive array substrate in accordance with another embodiment of the present invention.

7 is a schematic diagram of a reflective-transmissive array substrate according to another embodiment of the present invention.

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

G1, G2: scan line D1, D2, D3: data line

P1, P2: pixel portion 310, 330: switching element

317 and 337 pixel electrodes 319 and 339 reflector

T1, T2: transmissive portion R1, R2: reflective portion

Claims (12)

A first pixel portion having a first reflecting portion that reflects first light and a first transmitting portion that transmits second light; And A reflection-transmitting type including a second pixel portion adjacent to the first pixel portion, the second transmission portion adjacent to the first reflection portion and transmitting the second light, and a second reflecting portion reflecting the first light Array substrate. The reflection-transmissive array substrate of claim 1, wherein the first transmission portion is adjacent to the second reflection portion. The display device of claim 1, wherein the first pixel portion further comprises a first switching element connected to a first data line and a first scan line. And the first switching element is formed corresponding to the first transmission portion. 4. The display device of claim 3, wherein the second pixel unit further comprises a second data line adjacent to the first data line and a second switching element connected to the first scan line. And the second switching element is formed in correspondence with the second reflecting portion. The display device of claim 1, wherein the first pixel portion further comprises a first switching element connected to a first data line and a first scan line, wherein the second pixel portion is adjacent to the first data line and the first scan line. A second switching element connected to the second scan line, And the first switching element and the second switching element are formed corresponding to the first reflecting portion and the second reflecting portion, respectively. The display device of claim 1, wherein the first pixel portion further comprises a first switching element connected to a first data line and a first scan line, wherein the second pixel portion is adjacent to the first data line; A second switching element connected to the first scan line, The first switching element is formed in an area defined by the first scan line and the previous scan line of the first scan line, And the second switching element is formed in an area defined by the first scan line and a subsequent scan line of the first scan line. The reflection-transmissive array substrate of claim 6, wherein the first switching element and the second switching element are respectively formed corresponding to the first reflecting unit and the second reflecting unit. An array substrate having transmissive portions provided in adjacent pixel portions, and reflecting portions extending from each of the transmissive portions within the pixel portion, and alternately arranged pixel portions adjacent to each other; Liquid crystal layer; And And a color filter substrate having a color filter corresponding to each of the pixel units, and accommodating the liquid crystal layer through coalescence with the array substrate. The liquid crystal display of claim 8, wherein a light hole is further formed in a color filter at a position corresponding to the alternating reflection units. The method of claim 8, wherein the pixel portion includes a switching element, And a color filter requiring a large luminance amount among the color filters corresponding to a pixel portion having a reflecting portion covering the switching element. The liquid crystal display device according to claim 10, wherein the color filter requiring a large amount of luminance is a green filter. The method of claim 8, wherein the array substrate has a first pixel portion and a second pixel portion adjacent to the first pixel portion. The first pixel portion includes a first transmission portion that transmits second light and a first reflection portion that reflects the first light, and the second pixel portion is adjacent to the first pixel portion, and is adjacent to the first reflection portion. And a second transmission portion that transmits the second light, and a second reflection portion that reflects the first light.