KR20070041178A - Driving method for liquid crystal display - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving method of a liquid crystal display device, and more particularly to a driving method of a liquid crystal display device which can reduce the capacity of a memory by efficiently controlling the memory in a time division sequential driving method. In the method of driving a liquid crystal display device of a time division sequential driving method comprising a memory for dividing one frame into first to third subframes and processing first to third data corresponding to each subframe. (a) dividing the memory into twelve independently controllable small memories; (b) dividing the first data into first to third sub data, dividing the second data into fourth to sixth sub data, and dividing the third data into seventh to ninth sub data; (c) writing the first to ninth sub data into each of the small memories; And (d) write one sub data of each of the first to third data into an empty one of the twelve small memories, and simultaneously write one of the first to third data stored in the twelve small memories. And a reading step, wherein step (d) is repeated sequentially.

Description

DRIVING METHOD FOR LIQUID CRYSTAL DISPLAY}

1 is a view for explaining a liquid crystal display device of the FSC method according to the prior art.

2 is a view for explaining the operation of the memory in the FSC type liquid crystal display device according to an embodiment of the present invention.

3 is a view showing the structure of a memory in the FSC type liquid crystal display device according to an embodiment of the present invention.

4 is a diagram illustrating an input data block of a memory in an FSC type liquid crystal display according to an exemplary embodiment of the present invention.

5 is a data read timing diagram of each sub block in an FSC type liquid crystal display according to an exemplary embodiment of the present invention.

FIG. 6 is a view for explaining a procedure of memory read / write operation in an FSC type liquid crystal display according to an exemplary embodiment of the present invention. FIG.

FIG. 7 is a flowchart illustrating a memory operation according to a frame in an FSC type liquid crystal display according to an exemplary embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

110: memory M1 to M12: small memory

111 to 113: Sub block 120: Memory controller

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving method of a liquid crystal display device, and more particularly to a driving method of a liquid crystal display device which can reduce the capacity of a memory by efficiently controlling the memory in a time division sequential driving method.

In general, a liquid crystal display of a field division sequential driving method (hereinafter referred to as "FSC") is used to display red, green, and blue color filters. It is a liquid crystal display device which displays colors using the afterimage effect of a human eye by sequentially driving three primary colors (red, green, blue) without using them.

The FSC type liquid crystal display device divides a main frame on a panel into sub-frames of red (R), green (G), and blue (B), and FIG. 1. It will be described in detail with reference to.

1 is a view for explaining a liquid crystal display device of the FSC method according to the prior art.

As shown, the FSC type liquid crystal display device according to the prior art is composed of three subframes having a time of one frame, and each subframe is a red subframe (R sub-frame) and a green subframe (G Sub). -frame, and a blue subframe (B Sub-frame). Each subframe includes an addressing section, a waiting section, and a flashing section.

Here, the addressing section is a section in which data is loaded into the panel, and a section in which the data voltage is charged in the liquid crystal capacitor from the upper side (or the lower side) of the panel, and the weighting section is in accordance with the data voltage charged in the liquid crystal capacitor. It is a section to secure time to react. In addition, the flashing section is a section that emits light (LED) corresponding to each subframe, and is a section that emits luminance proportional to the degree of response of the liquid crystal and the area of the light emitting section.

In order to process data sequentially in the FSC type liquid crystal display according to the related art, a memory of one frame storing a previous frame and a memory of one frame for reading the current frame are required. In other words, the FSC type liquid crystal display device according to the related art includes first and second memories for storing a previous frame and reading the current frame.

In detail, the FSC method according to the related art first counts a frame signal and divides the frame signal into even and odd frames for each frame. Then, in even frames, data is written into the first memory, and data of the previous frame is read into the second memory. Then, in the odd frame, the data of the previous frame is read into the first memory, and the data of the current frame is written into the second memory.

The FSC type liquid crystal display device according to the related art requires a total memory of 345.6 Kbytes in order to read and write data in the case of 6bit / QVGA resolution. However, such a large capacity memory has a problem in that it has a large space and cost burden in the drive drive IC.

Therefore, the present invention was created to solve the problems inherent in the prior art as described above, and an object of the present invention is to independently control by using a plurality of small memory, instead of using two large memory, It is to provide a liquid crystal display device that can reduce the total capacity of the memory to 2/3 compared to the existing.

In accordance with an aspect of the present invention, a time division comprises a memory for dividing one frame into first to third subframes and processing first to third data corresponding to each subframe. A method of driving a sequential drive type liquid crystal display device, the method comprising: (a) dividing the memory into twelve compactly controllable memories; (b) dividing the first data into first to third sub data, dividing the second data into fourth to sixth sub data, and dividing the third data into seventh to ninth sub data; (c) writing the first to ninth sub data into each of the small memories; And (d) write one sub data of each of the first to third data into an empty one of the twelve small memories, and simultaneously write one of the first to third data stored in the twelve small memories. And a reading step, wherein step (d) is repeated sequentially.

In the method, the first subframe is a red subframe that emits a red light emitting diode as a main light source, the second subframe is a green subframe that emits a green light emitting diode as a main light source, and the third subframe is And a blue subframe which emits the blue light emitting diode as the main light source.

In the method, the step (d) may include writing the first sub data, the fourth sub data, and the seventh sub data into an empty one of the twelve small memories, and simultaneously storing the first sub data, the fourth sub data, and the seventh sub data. Reading first data of the first to third data; The second sub data, the fifth sub data, and the eighth sub data are written into an empty memory among the twelve small memories, and the second data among the first to third data stored in the twelve small memories is read. Making step; The third sub data, the sixth sub data, and the ninth sub data are written into an empty memory among the twelve small memories, and the third data among the first to third data stored in the twelve small memories is read. It is characterized in that it is repeated in the step;

(Example)

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

2 is a view for explaining the operation of the memory in the FSC type liquid crystal display device according to an embodiment of the present invention, Figure 3 is a view showing the structure of the memory in the FSC type liquid crystal display device according to an embodiment of the present invention to be.

As shown in FIG. 2 and FIG. 3, the FSC type liquid crystal display according to an exemplary embodiment of the present invention includes a memory 110 having a 4/3 frame and a memory controller 120 for controlling the memory 110. Include.

Here, the memory 110 includes 12 small memories M1 to M12, and each of the small memories M1 to M12 has a size of 1/9 frame. In addition, each of the small memories M1 to M12 can be independently controlled.

In addition, the memory controller 120 receives the input data (R, G, B) and the input control signal to output a memory control signal for controlling the memory 110 to the memory 110, and then, the memory 110 Reads and writes the data R, G, and B sequentially according to the memory control signal.

4 is a diagram illustrating an input data block of a memory in an FSC type liquid crystal display according to an exemplary embodiment of the present invention.

As illustrated, data in units of three sub-blocks 111, 112, and 113 are input to the memory 110.

In detail, first, red data R applied during a red subframe is divided into three red sub data R1, R2, and R3, and green data G applied during a green subframe is three green subframes. The data G1, G2, and G3 are divided, and the blue data B applied during the blue subframe is divided into three blue subdata B1, B2, and B3.

Then, the red, green, and blue sub data R1, G1, B1 constitute one input subblock 111, and the red, green, and blue sub data R2, G2, B2 are one input. The sub block 112 is configured, and the red, green, and blue sub data R3, G3, and B3 constitute one input sub block 113.

Subsequently, the FSC type liquid crystal display according to the exemplary embodiment of the present invention writes data of one sub block unit among the sub blocks 111 to 113 into the memory 110 for 4/3 frames.

As described above, in the FSC type liquid crystal display according to the exemplary embodiment of the present invention, the data R, G, and B corresponding to each subframe are divided into nine sub data R1 to R3, G1 to G3, and B1 to B3. The nine sub data R1 to R3, G1 to G3, and B1 to B3 are divided into three sub blocks 111 to 113 and then input to the memory 110.

5 is a data read timing diagram of each sub block in the FSC type liquid crystal display according to the exemplary embodiment of the present invention.

As shown, the memory reads out all the data R of the first sub-frame before the input of the sub-data R2, G2, B2 of the second sub-block 112. Then, the memory reads out all the data G of the second sub frame before input of the sub data R3, G3, and B3 of the third sub block 113.

Therefore, when the sub data R2, G2, B2 of the second sub block 112 is input to the memory, the small memories in which the data R1, R2, R3 of the first sub frame are input are empty. When the sub data R3, G3 and B3 of the third sub block are input to the memory, the small memories into which the data G1, G2 and G3 of the second sub frame are input are empty.

6 is a view for explaining the sequence of the memory read / write operation in the FSC type liquid crystal display according to an embodiment of the present invention, Figure 7 is a frame in the FSC type liquid crystal display according to an embodiment of the present invention A diagram illustrating a flow of memory operation according to this.

Here, numerals 1 to 12 of FIG. 6 represent small memories M1 to M12. For example, the number 1 corresponds to the small memory M1 and the number 2 corresponds to the small memory M2.

Hereinafter, the operation of the FSC type liquid crystal display device according to an exemplary embodiment of the present invention will be described in detail with reference to FIGS. 3 and 7.

First, all of the initial memory is left empty. In this case, when the first frame data R1 to R3, G1 to G3, and B1 to B3 are configured by three sub blocks 111 to 113, the FSC type liquid crystal display device according to an embodiment of the present invention is the first. The first frame data R1 to R3, G1 to G3, B1 to B3 are sequentially written from the first small memory M1 to the ninth small memory M9. The remaining three small memories M10 to M12 remain empty.

Next, when the two input data of the second (2 ^nd) frame, the liquid crystal display of FSC scheme according to the present invention is put to write the data in the following way.

First, the data R1, G1, and B1 of the sub block 111 are input to the empty small memories M10 to M12 of the previous frame, respectively. At this time, the memory designation, that is, the operation of inputting each data into the small memory is controlled by the memory controller 120.

At the same time, the FSC type liquid crystal display according to the exemplary embodiment of the present invention reads the red sub data R1, R2, and R3 input to the previous frame. Accordingly, in the FSC type liquid crystal display according to the exemplary embodiment of the present invention, the red sub data R1, R2, R3, that is, the data R1, G1, B1 of the sub block 111 is input. Since the reading of the red data R is completed, the small memories M1, M4, and M7 become empty.

Subsequently, in the FSC type liquid crystal display according to the exemplary embodiment of the present invention, the data R2, G2, and B2 of the sub block 112 are sequentially input to the small memories M1, M4, and M7, and the green sub data are displayed. Read (G1, G2, G3).

Then, in the FSC type liquid crystal display according to the exemplary embodiment of the present invention, the data R3, G3, and B3 of the sub block 113 are sequentially input to the small memories M2, M5, and M8, and the blue sub data. Read the fields B1, B2, and B3.

When this process is repeated, the FSC type liquid crystal display according to the exemplary embodiment of the present invention eventually returns to the first memory, that is, 'A' of FIG. By controlling the memory of three frames, data can be read / written in color order.

In other words, the FSC type liquid crystal display according to an exemplary embodiment of the present invention may read red data R of the small memories M1, M4, and M7 → green data of the small memories M2, M5, and M8 during a read operation. (G) → Data is read in order of "blue data (B)" of the small memories (M3, M6, M9). In the FSC type liquid crystal display according to the exemplary embodiment of the present invention, a vacant position of the first frame and a position where each data R and G are read during a write operation, that is, "small memories M11, M12, and M13". → Small memory (M1, M4, M7) → Small memory (M2, M5, M8) " Then, the FSC type liquid crystal display according to the embodiment of the present invention repeats the above operation.

Therefore, the FSC type liquid crystal display according to the embodiment of the present invention divides the memory of 4/3 frames into 12 small memories, and then executes the data read / write operation in the above order, thereby performing the 4/3 frame. Each data (R, G, B) is processed sequentially. Accordingly, the FSC type liquid crystal display device according to the embodiment of the present invention has the effect of reducing the memory capacity and the price by changing the memory control structure.

According to the above configuration of the present invention, in the time division sequential drive type liquid crystal display device, by changing the memory control structure, there is an effect of reducing the capacity of the memory and lowering the price.

While the invention has been shown and described with reference to specific embodiments, the invention is not limited thereto, and the invention is not limited to the scope of the invention as defined by the following claims. Those skilled in the art will readily appreciate that modifications and variations can be made.

Claims (3)

A method of driving a liquid crystal display device of a time division sequential driving method comprising dividing one frame into first to third subframes and processing a first to third data corresponding to each subframe. (a) dividing the memory into twelve independently controllable small memories; (b) dividing the first data into first to third sub data, dividing the second data into fourth to sixth sub data, and dividing the third data into seventh to ninth sub data; (c) writing the first to ninth sub data into each of the small memories; And (d) write one sub data of each of the first to third data into an empty one of the twelve small memories, and read one of the first to third data stored in the twelve small memories. Including; step, The driving method of the liquid crystal display device, characterized in that step (d) is repeated sequentially. The method of claim 1, The first subframe is a red subframe that emits a red light emitting diode as a main light source, the second subframe is a green subframe that emits a green light emitting diode as a main light source, and the third subframe is a blue light emitting diode. A method of driving a liquid crystal display device, characterized in that it is a blue subframe which emits light with a main light source. The method of claim 1, In step (d), The first sub data, the fourth sub data, and the seventh sub data are written to an empty memory among the twelve small memories, and the first data among the first to third data stored in the twelve small memories is read. Making step; The second sub data, the fifth sub data, and the eighth sub data are written into an empty memory among the twelve small memories, and the second data among the first to third data stored in the twelve small memories is read. Making step; The third sub data, the sixth sub data, and the ninth sub data are written into an empty memory among the twelve small memories, and the third data among the first to third data stored in the twelve small memories is read. The driving method of the liquid crystal display device, characterized in that it is repeated sequentially.

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