In Plane switching mode liquid crystal display device including 4 sub-pixels having different areas and fabrication method thereof

1. An in plane switching mode liquid crystal display device, comprising:

a first substrate and a second substrate;

a plurality of gate lines disposed horizontally on the first substrate;

a plurality of data lines disposed vertically on the first substrate, the plurality of gate lines and the plurality of data lines defining a first sub-pixel, a second sub-pixel, a third sub-pixel, and a fourth sub-pixel, wherein the sub-pixels are arranged in a 2×2 matrix form;

at least one pair of first and second electrodes disposed in each sub-pixel;

a first common line between the first and the second sub-pixels according to a first sub-pixel area ratio, the first common line connected to the first electrode disposed in the first and second sub-pixels;

a second common line between the third and the fourth sub-pixels according to a second sub-pixel area ratio, the second sub-pixel area ratio being different from the first sub-pixel area ratio, and the second common line connected to the first electrode disposed in the third and fourth sub-pixels;

a switching device formed at a crossing of the gate line and the data line; and

a liquid crystal layer formed between the first and the second substrates.

2. The device of claim 1 , wherein the first to fourth sub-pixels are Red (R), Green (G), Blue (B) and White (W) sub-pixels, respectively.

3. The device of claim 2 , wherein the first sub-pixel area ratio and the second sub-pixel area ratio substantially conform to a relation whereby a sum of the brightnesses of the R, G, and B sub-pixels substantially equals a brightness of the W sub-pixel.

4. The device of claim 1 , wherein the first electrode is a common electrode, and the second electrode is a pixel electrode.

5. The device of claim 1 , wherein the first common line and the second common line are electrically connected.

6. The device of claim 1 , wherein the switching device comprises:

a gate electrode;

a gate insulation film formed on an entire surface of a substrate including the gate electrode;

a semiconductor layer formed on the gate insulation film; and

a source and a drain electrodes on the semiconductor layer.

7. The device of claim 1 ,

further comprising pixel electrode lines disposed in the first area between the first sub-pixel and the second sub-pixel and in the second area between the third sub-pixel and the fourth sub-pixel overlapping the first or second common lines and to be connected to the second electrode disposed in each respective sub-pixel, the pixel electrode being overlapped with the first common line or the second common line in the first area and the second area.

8. The device of claim 1 , wherein the first common line is shared by the first and the second sub-pixels.

9. The device of claim 1 , wherein the second common line is shared by the third and the fourth sub-pixels.

10. The device of claim 1 , wherein the first and second electrodes have zigzag structures.

11. An in plane switching mode liquid crystal display device, comprising:

a first substrate and a second substrate;

a plurality of gate lines disposed horizontally on the first substrate;

a plurality of data lines disposed vertically on the first substrate;

a Red (R) sub-pixel, a Green (G) sub-pixel, a Blue (B) sub-pixel, and a White (W) sub-pixel defined by the gate lines and the data lines, wherein the sub-pixels are arranged in a 2×2 matrix form;

at least one pair of a common electrode and a pixel electrode disposed in each sub-pixel;

a first common line between the Red (R) and Green (G) sub-pixels according to a first area ratio (R/G), the first common line connected to the common electrode disposed in the Red (R) and Green (G) sub-pixels;

a second common line between the Blue (B) and White (W) sub-pixels according to a second area ratio (B/W), the second area ratio being greater than 1, the second common line connected to the common electrode disposed in the Blue (B) and White (W) sub-pixels;

pixel electrode lines in the first area between the first sub-pixel and the second sub-pixel and in the second area between the third sub-pixel and the fourth sub-pixel, one of the pixel electrode lines being overlapped with the first or second common lines in the first area and the second area, to form a storage capacitor together with the first or second common lines, and electrically connecting to the pixel electrode disposed in the respective sub-pixel;

a switching device formed at a crossing of the gate line and the data line; and

a liquid crystal layer formed between the first and the second substrates.

12. The device of claim 11 , wherein the first area ratio and the second area ratio substantially satisfy a relation whereby a sum of the brightnesses of the R, G, and B pixels substantially equal a brightness of the W pixel.

13. A method of fabricating an in plane switching mode liquid crystal display device, comprising:

providing a first substrate and a second substrate;

forming a plurality of gate lines, a common electrode, and a common line on the first substrate, wherein the common line includes first and second common lines, the first common line disposed substantially at a center between the gate lines, the second common line disposed off-center between the gate lines, wherein the first and second common lines are electrically connected;

forming a plurality of data lines disposed substantially perpendicularly to the gate lines and defining four sub-pixels together with the gate line and the first and the second common lines; pixel electrode lines disposed in the first area between the first sub-pixel and the second sub-pixel and in the second area between the third sub-pixel and the fourth sub-pixel to be overlapped with the first or second common lines in the first area and the second area and to form a storage capacitor; and a pixel electrode substantially parallel to the common electrode and electrically connected to one of the pixel electrode lines; and

forming a liquid crystal layer between the first and second substrates.

14. The method of claim of claim 13 , further comprising preparing the second substrate including:

forming a black matrix on the second substrate; and

forming a color filter on the second substrate.