Liquid crystal panel capable of controlling viewing angle and liquid crystal display device with the same

Abstract

Provided is a liquid crystal panel that limits a viewing angle. The liquid crystal panel includes a plurality of color pixels and a plurality of interference sub-pixels. Each of the color pixels includes red (R), green (G) and blue (B) sub-pixels. The interference sub-pixels are included in each of the color pixels and disposed on the same plane as the color pixels to control light that penetrates the liquid crystal panel and travels in side directions of the liquid crystal panel, except the front direction thereof. The viewing angle can be controlled by the interference sub-pixels. Since the interference sub-pixels and the color sub-pixels are disposed on the same plane, the thickness and weight of the liquid crystal panel do not increase. Further, it is possible to prevent the decrease of the light quantity and the degradation of the brightness.

Description

DRAWINGS

The accompanying drawings, which are included to provide a further understanding and are incorporated in and constitute a part of this application, illustrate embodiment(s) that serve to explain the principles of this application. In the drawings:

FIG. 1 is a sectional view of a related art liquid crystal panel capable of controlling a viewing angle;

FIGS. 2A to 2C illustrate the states of an image depending on viewing angles when the liquid crystal panel of FIG. 1 operates in a narrow viewing angle mode;

FIG. 3 is a plan view of a liquid crystal panel that limits a viewing angle;

FIG. 4 is a plan view of a liquid crystal panel that limits a viewing angle according to another embodiment;

FIG. 5 is a sectional view taken along a line A-A′ in FIGS. 3 and 4;

FIGS. 6A to 6C are graphs that illustrate the polarization characteristics of the liquid crystal panel in FIG. 5;

FIG. 7 is a block diagram of an LCD that limits a viewing angle;

FIGS. 8A and 8B illustrate the states of an image on a liquid crystal panel of the LCD of FIG. 7, which are viewed from the side in wide and narrow viewing angle modes, respectively;

FIG. 9 is a detailed block diagram that illustrates an embodiment of an interference data generator in FIG. 7;

FIG. 10A illustrates the characteristics of reference luminance data used in an operation unit of FIG. 9;

FIGS. 10B and 10C illustrate examples of interference sub-pixel data outputted from the operation unit of FIG. 9;

FIG. 11 is a flow diagram that illustrates an operation of the interference data generator in FIG. 9;

FIG. 12 is a detailed block diagram that illustrates another embodiment of an interference data generator in FIG. 7;

FIG. 13 illustrates an example of a memory map of a memory in FIG. 12;

FIG. 14 is a detailed block diagram that illustrates another embodiment of an interference data generator in FIG. 7;

FIG. 15 is a flow diagram that illustrates an operation of a memory controller in FIG. 14; and

FIG. 16 is a block diagram of an LCD that limits a viewing angle according to another embodiment.

Claims

1. A liquid crystal panel comprising: a plurality of color pixels each including red (R), green (G) and blue (B) sub-pixels; anda plurality of interference (E) sub-pixels included in each of the color pixels and disposed on one of the same plane and layer as the color pixels,wherein the plurality of interference (E) sub-pixels limit light that penetrates the liquid crystal panel and travels in the side directions of the liquid crystal panel.

2. The liquid crystal panel according to claim 1, wherein the sub-pixels in each of the color pixels are connected to a pair of gate lines and a pair of data lines.

3. The liquid crystal panel according to claim 2, wherein the R, G and B sub-pixels are driven by a horizontal electric field and the interference sub-pixels are driven by a vertical electric field.

4. The liquid crystal panel according to claim 2, wherein each of the R, G and B sub-pixels includes at least one or more band-shaped common electrodes that alternate with at least one or more band-shaped pixel electrodes; and wherein each of the interference sub-pixels includes a plate-shaped pixel electrode and a plate-shaped common electrode that face each other.

5. The liquid crystal panel according to claim 1, wherein the sub-pixels in each of the color pixels are connected commonly to one gate line and connected respectively to four data lines.

6. The liquid crystal panel according to claim 5, wherein the R, G and B sub-pixels are driven by a horizontal electric field and the interference sub-pixels are driven by a vertical electric field.

7. The liquid crystal panel according to claim 5, wherein each of the R, G and B sub-pixels includes at least one or more band-shaped common electrodes that alternate with at least one or more band-shaped pixel electrodes; and wherein each of the interference sub-pixels includes a plate-shaped pixel electrode and a plate-shaped common electrode that face each other.

8. A liquid crystal display device (LCD) comprising: the liquid crystal panel of claim 1;a data driver supplying pixel driving signals to the sub-pixels of the liquid crystal panel by one line;an interference data generator generating interference data that is supplied to the sub-pixels; anda video data combiner inserting the interference data to video data supplied to the data driver.

9. The LCD according to claim 8, wherein the interference data generator comprises: a memory storing interference sub-pixel data of an image with an interference pattern; anda memory controller controlling a read operation of the memory.

10. The LCD according to claim 9, wherein the interference data generator further comprises: an offset sub-pixel data generator generating offset sub-pixel data with a logic value that corresponds to an offset voltage; anda selector transferring selectively the offset sub-pixel data from the offset sub-pixel data generator and the interference sub-pixel data from the memory to the video data combiner in response to a wide/narrow mode control signal.

11. The LCD according to claim 10, wherein the offset sub-pixel data generator includes one of a register and a switch.

12. The LCD according to claim 9, wherein the memory further stores offset sub-pixel data with a logic value corresponding to an offset voltage; and wherein the memory controller operates the memory according to a wide/narrow mode control signal such that the offset sub-pixel data and the interference sub-pixel data stored in the memory are selectively read and transmitted to the video data combiner.

13. The LCD according to claim 8, wherein the interference data generator comprises: a data combiner combining R, G and B sub-pixel data contained in the video data; andan operation unit operating interference sub-pixel data on the basis of the combined sub-pixel data and supplying the calculated interference sub-pixel data to the video data combiner.

14. The LCD according to claim 13, wherein the operation unit performs an operation such that a luminance value of the interference sub-pixel data is distributed at a reference gray scale level.

15. The LCD according to claim 13, wherein the interference data generator further comprises: an offset sub-pixel data generator generating offset sub-pixel data with a logic value corresponding to an offset voltage; anda selector transferring selectively the offset sub-pixel data from the offset sub-pixel data generator and the interference sub-pixel data from the operation unit to the video data combiner in response to a wide/narrow mode control signal.

16. The liquid crystal panel according to claim 13, wherein the operation unit operates the interference sub-pixel data by setting the sum of R, G, B and E sub-pixel data with a gray scale level lower than the maximum gray scale level to a reference luminance data and subtracting the sum of the combined R, G and B sub-pixel data from the data combiner from the reference luminance data.

17. The LCD according to claim 16, wherein the operation unit comprises a processor performing an operation on the interference sub-pixel data using the combined R, G and B sub-pixel data from the data combiner.

18. The LCD according to claim 13, wherein the operation unit comprises a look-up table configured to supply the interference sub-pixel data to the video data combiner using the combined R, G and B sub-pixel data from the data combiner.

19. The LCD according to any one of claim 18, wherein the interference data generator further comprises: an offset sub-pixel data generator generating offset sub-pixel data with a logic value corresponding to an offset voltage; anda selector transferring selectively the offset sub-pixel data from the offset sub-pixel data generator and the interference sub-pixel data from the look-up table to the video data combiner in response to a wide/narrow mode control signal.

20. The LCD according to claim 19, wherein the offset sub-pixel data generator includes one of a register and a switch.