KR102366198B1 - Display Device and Driving Method Thereof - Google Patents

Abstract

The present invention relates to a display device including sub-pixels having a left-right asymmetric structure. In the memory of the display device, a red luminance weight corresponding to a red sub-pixel positioned at a first edge of the display panel, a green luminance weight corresponding to a green sub-pixel positioned at a second edge of the display panel, and the second edge of the display panel A blue luminance weight corresponding to the blue sub-pixel positioned at the third edge is stored, and the red luminance weight, the green luminance weight, and the blue luminance weight are set to be different from each other.

Description

Display Device and Driving Method Thereof

The present invention relates to a display device and a driving method thereof.

With the development of information technology, the importance of a display device, which is a connection medium between a user and information, has been highlighted. Accordingly, the use of display devices such as organic light emitting displays and liquid crystal displays is increasing.

A display device constitutes a pixel using a red sub-pixel, a green sub-pixel, and a blue sub-pixel, thereby realizing various color images.

The red sub-pixels, green sub-pixels, and blue sub-pixels may be arranged in various shapes, and are generally arranged in a stripe type. However, when the sub-pixels are arranged in a simple stripe form, the aperture ratio and high resolution implementation are limited, making it difficult to improve image quality.

In order to improve the image quality of a display device, various pixel rendering technologies including Pentile have been proposed. However, depending on the color arrangement of pixels, colors may be distorted or a specific color may stand out on a part of the screen.

The present invention provides a display device capable of optimizing the color arrangement of pixels to increase the aperture ratio and resolution, and to realize uniform color expression across the entire screen, and a driving method thereof.

A display device of the present invention includes: a display panel including pixels including sub-pixels having a left-right asymmetric structure; a memory for storing a plurality of luminance weights and a plurality of grayscale weights; a luminance determination unit configured to select the luminance weight according to a current luminance setting value of the display panel; a gradation determination unit configured to select the gradation weight according to an average luminance of current frame data displayed on the display panel; and a data modulator for lowering the luminance of data to be displayed on a partial area of the screen of the display panel based on the selected luminance weight and the gray scale weight.
In the memory, the i-th red luminance weight corresponding to the red sub-pixel positioned at the first edge of the display panel in the i-th luminance section (i is a natural number) corresponds to the green sub-pixel positioned at the second edge of the display panel The i-th green luminance weights corresponding to the i-th green luminance weights and the i-th blue luminance weights corresponding to the blue sub-pixels positioned at the third edge of the display panel are stored. The ith red luminance weight, the ith green luminance weight, and the ith blue luminance weight are set to be different from each other.

The method of driving the display device includes: storing a plurality of luminance weights and a plurality of grayscale weights in a memory; selecting the luminance weight according to a current luminance setting value of the display panel; a gradation determination unit configured to select the gradation weight according to an average luminance of current frame data displayed on the display panel; and lowering the luminance of data to be displayed on a partial area of the screen of the display panel based on the selected luminance weight and the gray scale weight.

According to the present invention, the aperture ratio of the pixel can be improved and high resolution can be realized by applying a color having an asymmetric structure in the pixel area. The present invention modulates data of sub-pixels that can be recognized as dominant colors in consideration of the current luminance setting value of the display panel and the grayscale of data, thereby providing a dominant color that can be recognized in a local area of the screen due to color arrangement of an asymmetric structure. can be prevented As a result, according to the present invention, the aperture ratio and resolution of the display device can be improved, and uniform color expression power can be realized without color distortion and dominant color over the entire screen.

1 is a diagram showing a sub-pixel arrangement structure according to an embodiment of the present invention.
FIG. 2 is an equivalent circuit diagram of the sub-pixels shown in FIG. 1 .
FIG. 3 is a cross-sectional view illustrating a cross-sectional structure of the sub-pixels shown in FIG. 1 .
FIG. 4 is a diagram showing a dominant color resulting from the asymmetric pixel arrangement structure shown in FIG. 1 .
5 is a block diagram illustrating a display device according to an embodiment of the present invention.
FIG. 6 is a block diagram illustrating the data processing unit shown in FIG. 5 .
7 is a diagram illustrating an example of setting luminance of a display panel.
8 is a diagram illustrating an example of application of a luminance weight and a gray scale weight according to an embodiment of the present invention.
9A and 9B are diagrams illustrating luminance weights according to an embodiment of the present invention.
10A and 10B are diagrams illustrating grayscale weights according to an embodiment of the present invention.
11 is a flowchart showing step-by-step operations of a data processing unit according to an embodiment of the present invention.

The display device of the present invention includes a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an organic light emitting diode display (OLED). , OLED Display), and electrophoresis (EPD), etc., can be implemented as a flat panel display capable of realizing color.

In the following description of the embodiment, a dominant color means a color that appears more prominent than other colors.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals refer to substantially identical elements throughout. In the following description, if it is determined that a detailed description of a known function or configuration related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

1 to 3 illustrate a pixel structure according to an embodiment of the present invention. It should be noted that the pixel structure of the present invention is not limited to Figs.

Referring to FIG. 1 , a display device according to an embodiment of the present invention includes a plurality of pixels P1 to P4 arranged in a matrix form. Each of the pixels P1 to P4 includes a red (Red, R) sub-pixel SPr, a green (Green, G) sub-pixel SPg, and a blue (Blue, B) sub-pixel SPb for color implementation. . In one pixel area, the RGB sub-pixels SPr, SPg, and SPb are arranged in a left-right asymmetric structure.

Each of the pixels P1 to P4 has a substantially rectangular shape having a horizontal length H and a vertical length V. Referring to FIG. The red and green sub-pixels SPr and SPg are alternately arranged along the first column in the y-axis direction. The first column is divided into a first row and a second row, and colors are distinguished in units of rows. A red sub-pixel SPr is disposed in a first row of the first column, and a green sub-pixel SPg is disposed in a second row of the first column. The blue sub-pixels SPb are continuously arranged along the second column.

The cross-sectional structure of the pixel is shown in FIG. 3 . In FIG. 3 , the color of the sub-pixel is determined by the red, green, and blue light-emitting layers 132 , 134 , and 136 (or light-emitting regions). The organic light emitting diode (OLED) includes a first electrode 130 , light emitting layers 132 , 134 , and 136 , and a second electrode 138 . In order to prevent shadowing between adjacent sub-pixels, the distance between the adjacent light emitting layers 132 , 134 , and 136 is set to be greater than or equal to a predetermined first distance d1 . The first distance d1 may be set to about 22 μm, but is not limited thereto.

The red and green light emitting layers 132 and 134 may be patterned in a rectangular shape having a width w1 greater than a height h1. The blue light emitting layer 136 may be patterned in a rectangular shape having a height h2 greater than a width w2.

Compared to a simple stripe-shaped color arrangement, the asymmetric color arrangement as shown in Fig. 1 can secure more margins in width and height, so even if the pixel size becomes smaller at high resolution, it is possible to design RGB color arrangement within a smaller pixel area. make it easy

FIG. 2 is an equivalent circuit diagram of the sub-pixels shown in FIG. 1 . FIG. 3 is a cross-sectional view illustrating a cross-sectional structure of the sub-pixels shown in FIG. 1 .

2 and 3 , the display device includes a plurality of scan lines SL1 and SL2 , a plurality of data lines DL1 to DL3 , and a plurality of power lines PL1 to PL3 .

Each of the sub-pixels SPr, SPg, and SPb includes a switching transistor Ts, a driving transistor Td, a storage capacitor Cst, and a light emitting diode Del. The positions of the switching transistor Ts, the driving transistor Td, and the storage capacitor Cst are not limited to the corresponding sub-pixels SPr, SPg, and SPb, and may be disposed in other adjacent sub-pixels.

In the light emitting diode Del, the first electrode 130 may be an anode connected to the source of the driving transistor Td. The second electrode 138 may be a cathode commonly connected to the pixels. The anode may be formed of a material such as indium-tin-oxide (ITO), and the electrode serving as the cathode may be formed of a material such as aluminum.

The emission layers 132 , 134 , and 136 are formed between the first electrode 130 and the second electrode 138 .

A first power line PL1 , a second data line DL2 , a second power line PL2 , and a third data line DL3 are interposed between the first data line DL1 and the third power line PL3 . Although illustrated as being sequentially disposed, the present invention is not limited thereto. For example, in a state in which the second power line PL2 is omitted and the second data line DL2 is formed at the position of the second power line PL2 , the driving transistor Td of the green sub-pixel SPg is removed. By connecting to the first power line PL1 , the red sub-pixel SPr and the green sub-pixel SPg may share the first power line PL1 .

The red sub-pixel SPr is driven by a signal supplied to the first scan line SL1 and the first data line DL1 . The green sub-pixel SPg is driven by a signal supplied to the first scan line SL1 and the second data line DL2. The blue sub-pixel SPb is driven by a signal supplied to the first scan line SL1 and the third data line DL3.

of pixels such as a plurality of scan lines SL, a plurality of data lines DL, a plurality of power lines PL, a driving transistor Td, a switching transistor Ts, a light emitting diode Del, and a storage capacitor Cst. Components are formed on the substrate 111 .

A semiconductor layer 112 including a gate insulating layer 114 , an active region 112a , a source region 112b , and a drain region 112c is formed on the substrate 111 .

The semiconductor layer 112 is made of a semiconductor material such as amorphous silicon or polycrystalline silicon. The active region 112a is made of pure silicon, and the source region 112b and the drain region 112c are made of impurity silicon ( It may be made of impuritydoped silicon, and the gate insulating layer 114 may be made of an inorganic insulating material such as a silicon nitride layer (SiNx) or a silicon oxide layer (SiO2).

A gate electrode 116 is formed on the gate insulating film 114 corresponding to the semiconductor layer 112 , and an interlayer insulating film 118 is formed on the entire surface of the substrate 111 on the gate electrode 116 .

The gate electrode 116 is made of a conductive metal material such as aluminum (Al) or an aluminum alloy, and the interlayer insulating film 118 is an inorganic insulating material such as a nitride film (SiNx), a silicon oxide film (SiO2), or benzocyclobutene. , may be made of an organic insulating material such as acrylic resin. The interlayer insulating layer 118 includes source and drain region contact holes 120a and 122a exposing the source and drain regions 112b and 112c, respectively.

A source electrode 120 , a drain electrode 122 , and a data line 124 are formed on the interlayer insulating layer 118 , and the source electrode 120 is connected to the source region 112b through the source region contact hole 120a. and the drain electrode 122 is connected to the drain region 112c through the drain region contact hole 122a.

The semiconductor layer 112 , the gate electrode 116 , the source electrode 120 , and the drain electrode 122 shown in FIG. 3 are components of the driving transistor Td. The switching transistor may also have the same structure as the driving transistor Td, and the scan line may be formed of the same layer and the same material as the gate electrode 116 .

A passivation layer 126 covering transistors and wirings is formed on the substrate 111 . The passivation layer 126 may be made of an inorganic insulating material such as a nitride layer (SiNx) or a silicon oxide layer (SiO2), or an organic insulating material such as benzocyclobutene or acrylic resin.

The first electrode is connected to the drain electrode 122 of the driving transistor Td through a contact hole 126a exposing the drain electrode 122 .

The pattern of the bank layer 128 is formed between the patterns of the first electrode 130 on the passivation layer 126 . The bank layer 128 includes a plurality of openings 128a exposing each of the first electrodes 130 . The bank layer 128 may be made of an inorganic insulating material such as a nitride film (SiNx) or a silicon oxide film (SiO2), or an organic insulating material such as benzocyclobutene or an acrylic resin.

Each of the light emitting layers 132 , 134 , and 136 may include multiple layers of an electron injecting layer (EIL), an emitting material layer (EML), and a hole injecting layer (HIL). However, the present invention is not limited thereto. A separate substrate (not shown) for encapsulation may be bonded to the substrate having the structure shown in FIG. 3 .

The above-described method for arranging sub-pixels having an asymmetric structure may make a dominant color visible at an edge of the display panel 170 . For example, in FIG. 4 , since the area of the red sub-pixel at the first edge of the display panel 170 is relatively large, red may be seen as a dominant color compared to other colors. Since the area of the green buff pixel at the second edge of the display panel 170 is relatively large, green may be viewed as a dominant color compared to other colors. Since only blue sub-pixels exist at the third edge of the display panel 170 , blue may be viewed as a dominant color compared to other colors. In FIG. 4 , the first edge is the uppermost horizontal line of the display panel 170 , and the second edge is the lowermost horizontal line of the display panel 170 . The third edge is a rightmost vertical line of the display panel 170 . A position where a dominant color appears may vary according to color arrangement of pixels.

The present invention lowers the gradation of data to be written in a sub-pixel of a dominant color by using a data modulation method. The present invention lowers the gradation of data that can be viewed as a dominant color and does not change the gradation of other data.

5 is a diagram illustrating a display device according to an embodiment of the present invention.

Referring to FIG. 5 , a display device according to an embodiment of the present invention includes a timing controller 190 (T-CON), a data processor 140 (DP), a data driver 150 (SD-IC), and a scan driver 160 and GD. -IC), a display panel 170 (PANEL) and a memory 180 are provided.

The timing controller 190 receives data of an input image and a timing signal synchronized with the data from an external host system. The timing signal includes a data enable signal, a vertical synchronization signal, a horizontal synchronization signal, and a clock signal. The data Data1 received by the timing controller 19 is modulated by the data processing unit 140 and output as second data Data2 . The second data Data2 is data to be written in the sub-pixels positioned at the first to third edges of the display panel 170 in the example of FIG. 4 . The host system may be any one of a television (Television) system, a set-top box, a navigation system, a DVD player, a Blu-ray player, a personal computer (PC), a home theater system, and a phone system.

The timing controller 190 generates timing control signals GDC and DDC for controlling the operation timings of the scan driver 160 and the data driver 150 based on the timing signal received from the host system. The timing controller 190 rearranges the data of the input image and supplies it to the data driver 150 .

The data driver 150 receives the data timing control signal DDC and the data Data from the timing controller 190 . The data driver 150 converts the data of the input image into an analog data signal by using the gamma voltage. An analog-to-digital conversion (ADC) of the data driver 150 converts a grayscale of data into a gamma voltage to generate a data signal. The data driver 150 supplies a data signal to the data lines DL1 to DLm to be synchronized with the scan signal.

The scan driver 160 generates a scan signal in response to the gate timing control signal GDC supplied from the timing controller 190 , and sequentially shifts the scan signal to select a line in which data is to be written.

As described above, in the display panel 170 , the colors of the sub-pixels may be arranged in an asymmetric structure of the RGB sub-pixels SPr, SPg, and SPb in the pixel area. Each of the sub-pixels SPr, SPg, and SPb expresses the grayscale of data by adjusting the light transmittance or the amount of light emission according to the data signal. Due to the color arrangement of the asymmetric structure, a dominant color may be seen in a local area that is a part of the screen of the display panel 17 . The present invention modulates data to be written in a sub-pixel of a local area on a screen to lower the luminance of the sub-pixel, thereby preventing a dominant color from being recognized.

The data processing unit 140 receives data Data from an external host. The data includes first data Data1. The first data Data1 refers to data supplied to the pixels of the first to third edges. it means.

The data processing unit 140 modulates the grayscale of the first data Data1 . The data processing unit 140 generates the second data Data2 by lowering the grayscale of the first data Data1 based on the current luminance of the display panel 170 and the average luminance of the current frame data. The current luminance is the luminance of the maximum gray level of the pixel data, and may be changed according to a user setting or illuminance of an external environment. If the current luminance setting value is not changed, the luminance for each gradation of the data does not change. On the other hand, when the current luminance setting value is changed, the luminance of the highest gradation is changed, and thus the luminance of the other gradation is also changed. The average luminance of the current frame data is the average luminance of an image displayed on the display panel 170 . The average luminance of the current frame data varies according to the gray level of the data even if the current luminance setting value is not changed.

The data processing unit 140 includes sub-pixels positioned at the first edge (ie, the red sub-pixel SPr) and the sub-pixels positioned at the second edge so that the dominant color is not recognized in the display panel 170 , that is, The gray level of the first data Data1 to be supplied to the green sub-pixel SPg) and the sub-pixels positioned at the third edge (ie, the blue sub-pixel SPb) is lowered. Since the luminance of pixels is proportional to the gradation of data, if the gradation of data to be written in sub-pixels positioned at the first, second, and third edges is lowered, the luminance of the sub-pixels is lowered. The data processing unit 140 lowers only the grayscale of data to be displayed in the pixel region where the dominant color is recognized, and does not change the grayscale of data to be displayed in other pixels. As a result, a phenomenon in which a dominant color is recognized in the asymmetric sub-pixel arrangement structure of the display panel 170 can be prevented, and colors can be uniformly reproduced over the entire screen.

A plurality of luminance weights and a plurality of grayscale weights for generating the second data Data2 are stored in the memory 180 . Although the memory 180 is illustrated as a separate configuration in FIG. 5 , the present invention is not limited thereto. For example, the memory 180 may be embedded in the data processing unit 140 , the timing control unit 190 , or the data driving unit 150 , or may be replaced with an existing built-in register.

Although the data processing unit 140 is illustrated as being separate from the timing control unit 190 , the present invention is not limited thereto. For example, the data processing unit 140 may be located inside the timing control unit 190 . In addition, the function of the data processing unit 140 may be processed in the form of an algorithm by the timing control unit 190 .

FIG. 6 is a diagram illustrating an embodiment of the data processing unit shown in FIG. 5 .

Referring to FIG. 6 , the data processing unit 140 according to an embodiment of the present invention includes a luminance determination unit 142 , a gray level determination unit 144 , and a data modulation unit 146 .

The current luminance of the display panel 170 may be adjusted according to a user's setting, an external environment, or the like. For example, as shown in FIG. 7 , when the highest luminance that can be displayed on the display panel 170 is 450 nits, the current luminance of the display panel 170 is 450 nits, 300 nits, 250 nits, or 150 nits depending on the illuminance of the user or external environment. and so on. The current luminance refers to a luminance of a maximum gray level of pixel data, for example, a gray level of 255 in the case of 8-bit pixel data. The luminance determination unit 142 determines the current luminance of the display panel 170 , and reads out a luminance weight corresponding to the current luminance from the memory 180 .

Even if the current luminance is the same, the perceived luminance is different for each gray level. The gray level determination unit 144 calculates the average luminance of one frame data (Data) to estimate the average gray scale of the image displayed on the display panel 170 , and reads the gray scale weight corresponding to the average luminance from the memory 180 . do. The average luminance may be calculated as an average picture level (APL). The average image level APL may be calculated by calculating the luminance of each pixel data (Y = 0.2R + 0.7G + 0.1B) and dividing the sum of the luminances of one frame data by the number of pixels.

The data modulator 146 generates the second data Data2 by lowering the grayscale of the first data Data1 by using the luminance weight and the grayscale weight. For example, the data processing unit 140 may generate the second data Data2 by multiplying the first data Data1 by a luminance weight and a grayscale weight.

8 is a diagram illustrating a method of setting a luminance weight and a grayscale weight. Although it has been exemplified in FIG. 8 that the luminance range that can be expressed in the display panel is divided into first to fifth sections and grayscales into first to fifth sections, the present invention is not limited thereto.

Referring to FIG. 8 , the luminance section of the display panel 170 may be selected according to a user setting or illuminance of an external environment. A luminance weight is independently set for each luminance section. In each of the luminance sections, a red luminance weight LWR, a green luminance weight LWG, and a blue luminance weight LWB are set.

The first section corresponds to the highest luminance range among the luminance ranges that can be expressed in the display panel 170 . The fifth section corresponds to the lowest luminance range among the luminance ranges that can be expressed in the display panel 170 . The luminance weight of the first section is divided into a first red luminance weight LWR1, a first green luminance weight LWG1, and a first blue luminance weight LWB1. The luminance weight of the second section is divided into a second red luminance weight LWR2, a second green luminance weight LWG2, and a second blue luminance weight LWB2. The luminance weight of the third section is divided into a third red luminance weight LWR3, a third green luminance weight LWG3, and a third blue luminance weight LWB3. The luminance weight of the fourth section is divided into a fourth red luminance weight LWR4, a fourth green luminance weight LWG4, and a fourth blue luminance weight LWB4 in correspondence with . The luminance weight of the fifth section is divided into a fifth red luminance weight LWR5, a fifth green luminance weight LWG5, and a fifth blue luminance weight LWB5. The luminance weights are stored in the memory 180 for each luminance section.

The luminance weights (LWR, LWG, LWB) are lower in the middle luminance compared to the high luminance and low luminance sections as shown in FIGS. 9A and 9B because dominant colors are better recognized at medium luminance than at high or low luminance. is set For example, the luminance weight may be set to a smaller value in the second section than in the first section, and set to a smaller value in the third section than in the second section. Also, the luminance weight may be set to a lower value in the fourth section than in the fifth section, and set to a lower value in the third section than in the fourth section. In other words, when the luminance range that can be expressed in the display panel is divided, the luminance weight value in the middle luminance section is smaller than the luminance weight value in the high luminance section and the low luminance section.

The luminance weights LWR, LWG, and LWB may be set between 0 and 1. The value of the luminance weights LWR, LWG, and LWB may be set so that it approaches from “1” to “0” from high luminance and low luminance to intermediate luminance. The luminance weights LWR, LWG, and LWB are multiplied by the first data Data1 that can be seen as a dominant color in the input image. Accordingly, when the luminance weights LWR, LWG, and LWB are low, the gray level of the second data Data2 is decreased.

When the current luminance of the display panel 170 is set to high luminance and low luminance, since the current luminance of the display panel 170 as a whole is bright or dark, a dominant color in the form of vertical and horizontal lines at the edge of the display panel 170 is not easily recognized At this time, when the current luminance of the display panel 170 is set to high luminance or low luminance, the luminance weights (LWR1, LWG1, LWB1 or LWR5, LWG5, LWB5) are set close to “1” or “1”, Accordingly, the second data Data2 is generated to have a grayscale equal to or slightly lower than the grayscale of the first data Data1.

When the current luminance of the display panel 170 is set to the intermediate luminance, the dominant color is easily recognized in the form of vertical and horizontal lines at the edge of the display panel 170 . Therefore, when the current luminance is set to the intermediate luminance, the luminance weights (LWR3, LWG3, LWB3) are smaller than the luminance weights (LWR1, LWG1, LWB1 and LWR5, LWG5, LWB5) in the high luminance and low luminance sections. For example, It can be set to 0.2. Since the luminance weights LWR3, LWG3, and LWB3 are low in the middle luminance section, the gray level of the second data Data2 is lower in the middle luminance section than in the high luminance and low luminance sections. Since the second data Data2 is sub-pixel data of the dominant color, when the gray level of the second data Data2 is lowered, a phenomenon in which the dominant color is recognized can be prevented.

The i-th red luminance weight LWRi, the i-th green luminance weight LWGi, and the i-th blue luminance weight LWBi set in the i-th section (i is 1 to 5) may be set differently. Each of the red sub-pixel Spr, the green sub-pixel SPg, and the blue sub-pixel SPb contributes differently to the luminance, and accordingly, the i-th red luminance weight LWRi, the i-th green luminance weight LWGi and The i-th blue luminance weights LWBi are set to be different from each other. For example, if the dominant color in blue is better recognized than other colors, the blue luminance weight LWBi may be set to a lower value than the luminance weights LWRi and LWGi of other colors. When the blue luminance weight LWBi is set in this way, the grayscale reduction width of blue data can be made larger than that of other colors. A method of differently setting luminance weights for each RGB is not limited thereto. The i-th red luminance weight LWRi is such that the horizontal red line is not recognized at the first edge of the display panel 170 , and the i-th green luminance weight LWGi is the horizontal green line at the second edge of the display panel 170 . In order not to be recognized, the i-th blue luminance weight LWBi may be experimentally determined so that the horizontal blue line is not recognized at the third edge of the display panel 170 .

A gray scale range (eg, 0 to 255 gray) that can be expressed on the display panel 170 is divided into a plurality of gray scale sections. The grayscale weights are independently set in each grayscale section. In each grayscale section, a red grayscale weight GWR, a green grayscale weight GWG, and a blue grayscale weight GWB are set.

The first section corresponds to the highest grayscale section among the grayscale ranges. The fifth section corresponds to the lowest gray scale section among the gray scale ranges. The gradation weight of the first section is divided into a first red gradation weight GWR1, a first green gradation weight GWG1, and a first blue gradation weight GWB1. The gradation weight of the second section is a second red gradation weight (GWR2), the second green gradation weight GWG2, and the second blue gradation weight GWB2. The gradation weight of the third section is divided into a third red gradation weight GWR3, a third green gradation weight GWG3, and a third blue gradation weight GWB3. The gradation weight of the fourth section is divided into a fourth red gradation weight GWR4, a fourth green gradation weight GWG4, and a fourth blue gradation weight GWB4. The gradation weight of the fifth section is divided into a fifth red gradation weight GWR5, a fifth green gradation weight GWG5, and a fifth blue gradation weight GWB5. These gray scale weights are stored in the memory 180 .

Here, the grayscale weights GWR, GWG, and GWB are set so that the average grayscale of one frame decreases from high grayscale to middle grayscale and from low grayscale to middle grayscale as shown in FIGS. 10A and 10B . The grayscale weight may be set to a smaller value in the second section than in the first section, and set to a smaller value in the third section than in the second section. Also, the grayscale weight may be set to a smaller value in the fourth section than in the fifth section, and set to a smaller value in the third section than in the fourth section. In other words, when the grayscale range that can be expressed on the display panel is divided, the grayscale weight value in the middle grayscale section is smaller than the grayscale weight value in the high grayscale section and the low grayscale section.

For example, the gradation weights (GWR, GWG, GWB) are set in the range of “0” to “1”, so that the value approaches from “1” to “0” as the gradation goes from the high gradation and low gradation to the middle gradation. can be set. Since the grayscale weights GWR, GWG, and GWB are multiplied by the first data Data1 that can be viewed as the dominant color, the lower the value of the grayscale weights, the lower the grayscale of the second data Data1.

If the average luminance of the current frame data of the display panel 170 is the luminance of the high grayscale and the low grayscale section, the dominant color is not well recognized compared to the middle grayscale section. If the average luminance of the current frame data is the luminance in the high grayscale or low grayscale section, the grayscale weights (GWR1, GWG1, GWB1 or GWR5, GWG5, GWB5) are close to “1” or set to “1”, and accordingly, the first The second data Data2 is generated to have a grayscale equal to or slightly lower than that of the data Data1.

If the average luminance of the current frame data is the luminance of the half-tone section, the dominant color may be recognized in the form of vertical and horizontal lines at the edge of the display panel 170 . Accordingly, the grayscale weights GWR3, GWG3, and GWB3 of the middle grayscale section are set to be smaller than the grayscale weights GWR1, GWG1, GWB1 and GWR5, GWG5, and GWB5 of the high grayscale and low grayscale, for example, "0.2". Then, the grayscale of the second data Data2 is significantly lowered compared to the first data Data1 , so that a phenomenon in which a dominant color is recognized at the edge of the display panel 170 can be prevented.

The ith red gradation weight GWRi, the ith green gradation weight GWGi, and the ith blue gradation weight GWBi set in the i-th section may be set to be different from each other. For example, the blue grayscale weight GWBi may be set to a lower value than the grayscale weights GWRi and GWGi of other colors, but is not limited thereto. The i-th red gradation weight GWRi is such that a horizontal red line is not recognized at the first edge of the display panel 170 , and the i-th green gradation weight GWGi is a green horizontal line at the second edge of the display panel 170 . In order not to be recognized, the i-th blue grayscale weight GWBi is experimentally determined so that the horizontal blue line is not recognized at the third edge of the display panel 170 .

As described above, in the embodiment of the present invention, data to be written in sub-pixels in which a dominant color can be recognized is modulated in consideration of the current luminance setting value of the display panel 170 and the average luminance of the current frame data. . If the second data Data2 is modulated in consideration of only the current luminance setting value, the dominant color may be recognized according to the grayscale of the data. In addition, when the second data Data2 is generated in consideration of only the average luminance of the current frame, the dominant color may be recognized when the current luminance setting value of the display panel 170 is changed. Accordingly, in the embodiment of the present invention, the second data Data2 is generated in consideration of the current luminance setting value of the display panel 170 and the average luminance of the current frame data at the same time, and the current luminance setting value or data of the display panel 170 is generated. Even if the gradation of , it is possible to prevent the dominant color from appearing. As a result, the present invention can realize image quality without color distortion on the entire screen and without local dominant colors.

11 is a diagram illustrating an operation process of a data processing unit according to an embodiment of the present invention. Referring to FIG. 11 , a method of generating the second data Data2 according to an embodiment of the present invention will be described as follows.

<Select a luminance weight corresponding to the current luminance setting value: S200, S202>

The luminance determining unit 142 determines a current luminance setting value set on the display panel 170 . The data processing unit 140 checks to which luminance section the current luminance set value belongs, and reads the luminance weights LWRi, LWGi, and LWBi of the corresponding section, for example, the i-th section, from the memory 180 .

<Select gradation weight corresponding to average luminance: S204, S206>

The gray level determination unit 144 obtains an average luminance of the current frame data. The gray level determination unit 144 checks the gray level section corresponding to the average luminance of the current frame data, and stores the gray level weight of the corresponding section, for example, the gray level weights (GWRi, GWGi, GWBi) of the i-th section, from the memory 180 . Read from (180).

<Second data generation: S208>

The data modulator 146 multiplies the selected luminance weights (LWRi, LWGi, LWBi) of the i-th section and the gray-scale weights (GWRi, GWGi, GWBi) of the i-th section by sub-pixel data in which a dominant color can be recognized, and the data By modulating , the second data Data2 is generated. The data modulator 146 generates second data Data2(R) to be supplied to the red sub-pixel SPr located at the first edge by using Equation (1).

In Equation 1, Data1(R) means first data Data1 to be supplied to the red sub-pixel SPr located at the first edge. In Equation 1, if the grayscale of Data1(R) is set to 233, the ith red luminance weight LWRi is set to 0.5, and the ith red grayscale weight GWRi is set to 0.6, then Data2(R) is generated to have a grayscale of approximately 70 .

The data modulator 146 generates second data Data2(G) to be supplied to the green sub-pixel SPg located at the second edge by using Equation (2).

In Equation 2, Data1(G) means first data Data1 to be supplied to the green sub-pixel SPg located at the second edge. In Equation 2, if the grayscale of Data1(G) is set to 160, the i-th red luminance weight LWRi is set to 0.93, and the i-th red grayscale weight GWRi is set to 0.85, Data2(R) is generated to have a grayscale of approximately 126. .

The data modulator 146 generates second data Data2(B) to be supplied to the blue sub-pixel SPb positioned at the third edge by using Equation (3).

In Equation 3, Data1(B) means the first data Data1 to be supplied to the blue sub-pixel SPb located at the third edge. In Equation 3, if the grayscale of Data1(B) is set to 180, the ith blue luminance weight LWRi is set to 0.9, and the ith blue grayscale weight GWRi is set to 0.8, Data2(R) is generated to have a grayscale of approximately 130. .

The second data Data2 modulated by the data modulator 1460 and other data are transmitted to the data driver 150 through the timing controller 190 . The data driver 150 converts the data Data and Data2 into a gamma voltage to generate a data signal, and supplies the data signal to the data lines DL1 to DLm.

The data signal of the second data Data is supplied to a local pixel area where a dominant color can be seen, for example, sub-pixels located at the edge of the display panel 170 . As described above, since the gradation of the second data Data is lowered according to the luminance setting value of the display panel 170 and the average luminance of the current frame data, the luminance of the sub-pixel to which the data is to be written is lowered, so that the dominant color is not recognized . Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the technical configuration of the present invention can be changed to other specific forms by those skilled in the art to which the present invention pertains without changing the technical spirit or essential features of the present invention. It will be appreciated that this may be practiced.

It should be understood that the embodiments described above are illustrative in all respects and not restrictive. In addition, the scope of the present invention is indicated by the claims to be described later rather than the above detailed description. In addition, all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention.

SPr: red sub-pixel SPg: green sub-pixel
SPb: blue sub-pixel 132: red light emitting layer
134: green light emitting layer 136: blue light emitting layer
140: data processing unit 142: luminance determination unit
144: gray level determination unit 146: data modulation unit
150: data driver 160: scan driver
170: display panel 180: memory
190: timing control

Claims (11)

a display panel including pixels including sub-pixels having a left-right asymmetric structure;
a memory for storing a plurality of luminance weights and a plurality of grayscale weights;
a luminance determination unit configured to select the luminance weight according to a current luminance setting value of the display panel;
a gradation determination unit configured to select the gradation weight according to an average luminance of current frame data displayed on the display panel; and
a data modulator for lowering the luminance of data to be displayed on a partial area of the screen of the display panel based on the selected luminance weight and the gray scale weight;
In the memory, the i-th red luminance weight corresponding to the red sub-pixel positioned at the first edge of the display panel in the i-th luminance section (i is a natural number) corresponds to the green sub-pixel positioned at the second edge of the display panel an i-th green luminance weight corresponding to a blue sub-pixel positioned at a third edge of the display panel is stored;
and the ith red luminance weight, the ith green luminance weight, and the ith blue luminance weight are set to be different from each other. The method of claim 1,
and the data modulator multiplies the selected luminance weight and the gray level weight to the data to lower the gray level of the data. The method of claim 1,
The red sub-pixel is
is disposed in the first row of the first column and includes a red light-emitting region;
The green sub-pixel is
is disposed in the second row of the first column and includes a green light emitting area;
The blue sub-pixel is
is disposed in the second column corresponding to the first row and the second row of the first column and includes a blue light emitting region;
Each of the red light emitting region and the green light emitting region has a rectangular shape in which a length in a horizontal direction is greater than a length in a vertical direction,
The blue light emitting region has a rectangular shape in which the length in the vertical direction is greater than the length in the horizontal direction. delete The method of claim 1,
The luminance weight is set to a lower value in the middle luminance section than in the high luminance section and the low luminance section,
The gray scale weight is set to a lower value in the middle gray scale section than in the high gray scale section and the low gray scale section. delete The method of claim 1,
In the memory, an i-th gray-scale weight corresponding to the red sub-pixel, an i-th green gray-scale weight corresponding to the green sub-pixel, and an i-th blue color corresponding to the blue sub-pixel in the i-th (i is a natural number) grayscale section gradation weights are stored;
and the ith red gradation weight, the ith green gradation weight, and the ith blue gradation weight are set to be different from each other. A method of driving a display device including sub-pixels having an asymmetric structure, the method comprising:
storing a plurality of luminance weights and a plurality of grayscale weights in a memory;
selecting the luminance weight according to a current luminance setting value of the display panel;
selecting the grayscale weight according to the average luminance of current frame data displayed on the display panel; and
lowering the luminance of data to be displayed on a partial area of the screen of the display panel based on the selected luminance weight and the gray scale weight;
In the memory, the i-th red luminance weight corresponding to the red sub-pixel positioned at the first edge of the display panel in the i-th luminance section (i is a natural number) corresponds to the green sub-pixel positioned at the second edge of the display panel an i-th green luminance weight corresponding to a blue sub-pixel positioned at a third edge of the display panel is stored;
and the ith red luminance weight, the ith green luminance weight, and the ith blue luminance weight are set to be different from each other. 9. The method of claim 8,
The step of lowering the luminance of the data is
and multiplying the data by the selected luminance weight and the gray level weight to lower the gray level of the data. delete 9. The method of claim 8,
The luminance weight is set to a lower value in the middle luminance section than in the high luminance section and the low luminance section,
The gray scale weight is set to a lower value in the middle gray scale section than in the high gray scale section and the low gray scale section.

Images