KR20210063733A - Light Emitting Display and Driving Method of the same - Google Patents

Abstract

The present invention provides a light emitting display device, which comprises: a display panel for displaying an image; an average image level calculation unit for calculating an average image level for the input image; a peak luminance control unit for controlling peak luminance for each of at least one frame based on the average image level; and a luminance setting unit outputting a luminance setting signal separately controlling the peak luminance control unit to enable brightness of a first image and a second image to be same when the first image and the second image having the different average image levels are displayed on a single screen of the display panel.

Description

Light Emitting Display and Driving Method of the Same

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

As information technology develops, the market for display devices, which is a connection medium between users and information, is growing. Accordingly, the use of display devices such as a light emitting display (LED), a quantum dot display (QDD), and a liquid crystal display (LCD) is increasing.

The display devices described above include a display panel including sub-pixels, a driving unit outputting a driving signal for driving the display panel, and a power supply unit generating power to be supplied to the display panel or the driving unit.

In the above display devices, when a driving signal, for example, a scan signal and a data signal, is supplied to the sub-pixels formed in the display panel, the selected sub-pixel transmits light or directly emits light, thereby displaying an image. .

On the other hand, among the display devices described above, the light emitting display device has many advantages such as fast response speed, high brightness, wide electrical and optical properties, and mechanical properties that can be implemented in a flexible form. However, since the light emitting display device still has improvement points in terms of the configuration of the display panel, continuous research in this regard is required.

An object of the present invention is to provide a light emitting display device and a driving method thereof that can achieve the same screen brightness as a whole, realize an image without burn-in of an organic light emitting diode, and improve the lifespan and display quality of the device.

As a means for solving the above problems, the present invention provides a display panel for displaying an image; an average image level calculator for calculating an average image level for the input image; a peak luminance control unit for controlling peak luminance for at least one frame based on the average image level; and when the first image and the second image having different average image levels are displayed on one screen of the display panel, the luminance for separately controlling the peak luminance controller so that the brightness of the first image and the second image are the same Provided is a light emitting display device including a luminance setting unit for outputting a setting signal.

When the average image level of the first image and the second image is different from the average image level of the luminance setting unit, and one of the first image and the second image exceeds the internal average image level, the peak luminance curve of the peak luminance control unit can be changed to a straight line.

The luminance setting unit may change the peak luminance curve of the peak luminance control unit into a straight line when the average image level of one of the first image and the second image is 70% or more and 100% or less.

The internally set average image level may be varied based on analysis of the input image and a user's setting value.

The peak luminance control unit may output a first luminance control signal for local peak luminance control or a second luminance control signal for overall peak luminance control in response to the luminance setting signal.

The peak luminance control unit outputs the second luminance control signal when the average image level of one of the first image and the second image is 70% or more and 100% or less, and outputs the second luminance control signal of one of the first image and the second image. When the average image level falls below 70% or 60%, the first luminance control signal may be output.

In another aspect, the present invention provides a method comprising: normally driving a display panel; controlling a peak luminance curve such that, when the driving condition of the display panel is changed to a cinema mode, the brightness of images displayed in all areas of the display panel is the same; and terminating the cinema mode when the cinema mode exceeds a time set therein.

The controlling of the peak luminance curve may include changing the peak luminance curve into a straight line.

When the driving condition of the display panel is changed to the cinema mode and the first image and the second image having different average image levels are displayed on one screen of the display panel, the brightness of the first image and the second image is increased. The peak luminance curve may be changed into a straight line to be the same.

When the average image level of one of the first image and the second image is 70% or more and 100% or less, the peak luminance curve may be changed into a straight line.

According to the present invention, when there is a section with a high average image level among images displayed on the display panel, the peak luminance curve is changed to a straight line within a range that does not violate the power consumption standard, so that the overall brightness of the screen can be similarly and identically implemented. there is an effect In addition, the present invention has the effect of realizing an image without burn-in of the organic light emitting diode and improving the lifespan and display quality of the device. In addition, the present invention has the effect of maximizing the user's satisfaction by giving the customer a choice for compensation for luminance degradation.

1 is a schematic block diagram of a light emitting display device according to an embodiment of the present invention, FIG. 2 is a schematic circuit configuration diagram of a sub-pixel, and FIG. 3 is an exemplary configuration diagram of a device related to a gate-in panel type scan driver. , FIG. 4 is a diagram illustrating an arrangement example of a shift register circuit unit, and FIG. 5 is an exemplary diagram illustrating a circuit for driving a display panel having RGBW sub-pixels.
6 is a block diagram showing the main configuration of a light emitting display device according to an embodiment of the present invention, FIG. 7 is a diagram for explaining luminance control according to the complexity of a frame, and FIG. 8 is a local luminance control by region analysis. It is a diagram for explaining, and FIG. 9 is a diagram for explaining luminance control through current analysis.
FIG. 10 is an exemplary diagram of an average image level observed when two images are displayed on one screen of a display panel, FIG. 11 is an exemplary diagram illustrating a peak luminance curve when the brightness setting unit is not in operation according to an embodiment, and FIG. 12 is an exemplary diagram showing a peak luminance curve during operation of the luminance setting unit according to the embodiment, and FIGS. 13 and 14 are diagrams for explaining the relationship between the operation and non-operation of the luminance setting unit according to the embodiment.
15 is a flowchart illustrating a method of driving a light emitting display device according to an exemplary embodiment of the present invention.

Hereinafter, specific details for carrying out the present invention will be described with reference to the accompanying drawings.

The light emitting display device according to the present invention is implemented as a television, an image player, a personal computer (PC), a home theater, a smart phone, and the like. The light emitting display device is implemented based on an inorganic light emitting diode or an organic light emitting diode. However, hereinafter, for convenience of description, an example implemented based on an organic light emitting diode will be described.

1 is a schematic block diagram of a light emitting display device according to an embodiment of the present invention, FIG. 2 is a schematic circuit configuration diagram of a sub-pixel, and FIG. 3 is an exemplary configuration diagram of a device related to a gate-in panel type scan driver. , FIG. 4 is a diagram illustrating an arrangement example of a shift register circuit unit, and FIG. 5 is an exemplary diagram illustrating a circuit for driving a display panel having RGBW sub-pixels.

1 , in the light emitting display device according to the embodiment of the present invention, an image processing unit 110 , a timing control unit 120 , a data driving unit 130 , a scan driving unit 140 , a power supply unit 180 and a display A panel 150 is included.

The image processing unit 110 outputs a data enable signal DE along with the data signal DATA supplied from the outside. The image processing unit 110 may output one or more of a vertical synchronization signal, a horizontal synchronization signal, and a clock signal in addition to the data enable signal DE, but these signals are omitted for convenience of description.

The timing controller 120 receives the data signal DATA from the image processor 110 as well as a driving signal including a data enable signal DE or a vertical synchronization signal, a horizontal synchronization signal, and a clock signal. The timing controller 120 includes a gate timing control signal GDC for controlling the operation timing of the scan driver 140 and a data timing control signal DDC for controlling the operation timing of the data driver 130 based on the driving signal. output, etc.

The data driver 130 samples and latches the digital data signal DATA supplied from the timing controller 120 in response to the data timing control signal DDC supplied from the timing controller 120 , and then sets the gamma reference voltage. It is converted into analog data voltage based on the output. The data driver 130 outputs a data voltage through the data lines DL1 to DLn. The data driver 130 may be formed in the form of an integrated circuit (IC).

The scan driver 140 outputs a scan signal in response to the gate timing control signal GDC supplied from the timing controller 120 . The scan driver 140 outputs a scan signal including a scan high voltage and a scan low voltage through the gate lines GL1 to GLm. The scan driver 140 is formed in the form of an integrated circuit (IC) or is formed in the display panel 150 in the form of a gate in panel. A description related to the gate-in-panel type scan driver will be provided below.

The power supply unit 180 is connected to the first power line EVDD and the second power line EVSS disposed on the display panel 150 . The power supply unit 180 outputs a first potential voltage (high potential voltage) and a second potential voltage (low potential voltage) through the first power line EVDD and the second power line EVSS. The first potential voltage (high potential voltage) and the second potential voltage (low potential voltage) transmitted through the first power line EVDD and the second power line EVSS are applied to the sub-pixels SP of the display panel 150 . ) is approved.

The display panel 150 displays an image in response to the voltage supplied from the power supply unit 180 , the data voltage supplied from the data driver 130 and the scan driver 140 , and the scan signal. The display panel 150 includes sub-pixels SP that operate to display an image. The sub-pixels SP may have one or more different light-emitting areas according to light-emitting characteristics (material, lifespan, luminous intensity, etc. of the device).

As shown in FIG. 2 , one sub-pixel SP is electrically connected to a data line DL1 , a gate line GL1 , a first power line EVDD, and a second power line EVSS. One sub-pixel SP includes an organic light emitting diode (OLED) emitting light and a pixel circuit (CC) driving the same.

The pixel circuit CC includes a switching transistor for transmitting a data voltage, a capacitor for storing the data voltage, a driving transistor for generating a driving current based on the data voltage stored in the capacitor, and the like. The pixel circuit CC may further include a compensation circuit for compensating for deterioration of a driving transistor or an organic light emitting diode (OLED).

3 and 4 , the gate-in-panel type scan driver may include a shift register circuit unit 131 (a scan signal generator) and a level shifter 135 (a clock signal and voltage generator). . The level shifter 135 generates and outputs a plurality of clock signals Gclk and a start signal Gvst based on the signals output from the timing controller 120 .

The shift register circuit unit 131 operates based on a plurality of clock signals Gclk and start signals Gvst output from the level shift unit 135 , and scan signals Scan[ 1] ~ Scan[m]) is created and printed.

The shift register circuit unit 131 may be disposed in the left and right non-display areas NA of the display panel 150 as shown in FIG. 4A . Also, the shift register circuit unit 131 may be disposed in the upper and lower non-display areas NA of the display panel 150 as shown in FIG. 4B . In the case of the shift register circuit unit 131, it has been shown and described as an example that the shift register circuit unit 131 is arranged in pairs in the non-display area NA located on the left, right, upper and lower sides of the display area AA. may be, but is not limited thereto.

5 , the display panel 150 may include pixels P including a red sub-pixel, a green sub-pixel, a blue sub-pixel, and a white sub-pixel RGBW. That is, the display panel 150 displays an image based on sub-pixels further including a white sub-pixel W in addition to a red sub-pixel, a green sub-pixel, and a blue sub-pixel RGB.

As such, when the display panel 150 includes the pixels P including the red sub-pixel, the green sub-pixel, the blue sub-pixel, and the white sub-pixel RGBW, one of the image processing unit 110 and the timing control unit 120 . At least one may be implemented to change the RGB data signal RGB input from the outside to the RGBW data signal RGBW in accordance with the pixel structure of the display panel 150 . In addition, the data driver 130 that directly drives the display panel 150 based on the RGBW data signal RGBW and the gamma unit 135 that provides a gamma voltage to the data driver 130 are also pixels of the display panel 150 . It can be implemented according to the structure.

Hereinafter, in the present invention, it is described as an example that the display panel 150 includes pixels P including red sub-pixels, green sub-pixels, blue sub-pixels, and white sub-pixels RGBW, but the present invention is not limited thereto. does not Also, in the following description, a panel control unit in which the image processing unit 110 and the timing control unit 120 are integrated into one will be described as an example, but the present invention is not limited thereto.

6 is a block diagram showing the main configuration of a light emitting display device according to an embodiment of the present invention, FIG. 7 is a diagram for explaining luminance control according to the complexity of a frame, and FIG. 8 is a local luminance control by region analysis. It is a diagram for explaining, and FIG. 9 is a diagram for explaining luminance control through current analysis.

As shown in FIG. 6 , the panel control unit 110; 120 includes a gamma correction unit 111, GMA COR, a data conversion unit 112, RGB TO RGBW, a color temperature correction unit 113, WCT, and a current prediction unit ( 114, CPRE), average image level calculation unit (121, APL), peak brightness control unit (122, PLC), brightness setting unit (123, PLCC), temperature brightness control unit (124, TPC), automatic current limiting unit (125, ACL GL), a gain-gain generator 126 (ACL GG), and a luminance converter 127 (LUM TO DAC).

The gamma correction unit 111 (GMA COR) serves to de-gamma-process the RGB data signal RGB included in one frame image. For example, the gamma correction unit 111 may be configured to convert an externally inputted RGB data signal RGB into an RGBW data signal RGBW to prevent a bit overflow occurring during an operation of receiving the received inverse gamma (Inverse Gamma). ) is de-gamma-treated to convert it to a linear form, and then bit stretching can be performed. Here, the RGB data signal RGB may be output after being changed from 10 bits (10 bits) to 12 bits (12 bits) by bit stretching by the gamma correction unit 111 . The gamma correction unit 111 may perform bit stretching using a lookup table, but is not limited thereto.

The data conversion unit 112 (RGB TO RGBW) serves to convert the RGB data signal RGB output through the gamma correction unit 111 into an RGBW data signal RGBW. The reason for converting the RGB data signal RGB into the RGBW data signal RGBW using the data converter 112 is to drive a display panel including RGBW sub-pixels.

When the color coordinates of the W data signal in the RGBW data signal RGBW output through the data conversion unit 112 are different from the target value, the color temperature correction unit 113 (WCT) lights the remaining RGB data signals RGB as much as necessary. It serves to compensate for the desired color temperature (or color coordinates) to be expressed.

The current prediction unit 114 (CPRE) predicts the total current for each frame based on the RGBW data signal RGBW output through the color temperature correction unit 113 and the current limit value output through the automatic current limiter 125. do The current prediction unit 114 counts the frequency of the luminance representative values through histogram analysis of the RGBW data signal (RGBW), calculates the representative current for each luminance representative value to which the peak luminance is applied, and then counts the representative value in the representative current The total predicted current for each frame may be calculated by summing all the multiplication results and calculating the total current for each frame, but is not limited thereto.

The average picture level calculator 121 (APL) serves to calculate an average picture level (APL) for the input RGB data signal RGB. The average image level calculating unit 121 calculates the average of the representative values again in units of the Nth frame (eg, 5 frames or 30 frames, etc.) so that the same average image level is applied to a plurality of frames (frames of a certain amount). process can be recalculated. This is to prevent problems such as flicker if it is expressed by calculating for every frame.

The average image level calculator 121 calculates the complexity of the frame based on the average image level (APL) as shown in FIG. 7 and provides a calculated value for controlling the luminance by increasing or decreasing the current accordingly. can do. The average image level calculator 121 may calculate an average image level based on moving AVG or calculate an average image level based on scene change detection, but is not limited thereto. .

The peak luminance controller 122 (PLC) serves to control the peak luminance for each frame based on the average image level calculated by the average image level calculator 121 (Peak Luminance Control). The peak luminance control unit 122 may control the peak luminance for each frame by further referring to the lookup table in addition to the average image level in order to reduce power consumption.

As shown in FIG. 8 , the peak luminance control unit 122 may perform local luminance improvement by analyzing the middle/high region of the average image level. The peak luminance control unit 122 may perform local boosting in a range not exceeding the normal peak as well as local boosting for local peak luminance improvement, but is not limited thereto.

The luminance setting unit 123 ( PLCC ) may separately control the peak luminance control unit 122 by analyzing the input RGB data signal (RGB) and referring to the user's setting value. The luminance setting unit 123 may refer to the average image level calculated from the average image level calculating unit 121 to analyze the RGB data signal RGB.

The temperature luminance control unit 124 (TPC) serves to additionally control the peak luminance for each frame in consideration of a specific temperature condition higher than room temperature. The temperature luminance control unit 124 may increase or decrease the peak luminance according to temperature conditions.

The automatic current limiter 125 (ACL GL) serves to automatically limit the current gain for each frame according to the image analysis result for each frame. The automatic current limiter 125 includes the average image level output from the average image level calculator 121, the temperature condition output from the temperature luminance controller 124, and the gain gain generator 126 to automatically limit the current gain for each frame. ), a gain for each frame (FRAMEg) may be generated based on the repeat gain (RPg) output from the .

The gain gain generator 126 (ACL GG) serves to generate a gain based on the total predicted current value CURd for each frame of the current RGBW data signal RGBW output from the current predictor 114 . The gain-gain generator 126 may generate a gain so that the change in the output current compared to the input expected current changes only after a specific expected current value so as to control luminance through current analysis, as shown in FIG. 9 , but is not limited thereto. .

The luminance converter 127 (LUM TO DAC) serves to receive the luminance value for the final peak luminance from the automatic current limiter 125 and convert the luminance value into a voltage value. Since the luminance converter 127 can generate a driving voltage based on the current-limited data by the operation of the automatic current limiter 125 , it is possible to provide a basis for reducing power consumption when driving the display panel. The luminance converter 127 may convert the luminance value into a voltage value based on a digital-to-analog converter, but is not limited thereto.

The programmable gamma unit 130 (PGMA) serves to prepare a gain voltage value for each frame based on a voltage value corresponding to the luminance value output from the luminance converter 127 and supply it to the data driver 135 (DIC). . Meanwhile, although the programmable gamma unit 130 is provided as a separate IC from the data driver 135 as an example, it may be included in the data driver 135 .

The panel controller 110 ( 120 ) in which the abnormal image processing unit and the timing controller are integrated into one can control the luminance according to the frame image, improve the local luminance, and control the luminance through current analysis. In addition, power consumption can be reduced when the display panel is driven by the method of the above embodiment. In addition, in the method of the above embodiment, the brightness of the screen of the display panel can be uniformly maintained even in a section (high APL) in which the average image level is high by the operation of the luminance setting unit 123 , which will be described as follows.

10 is an exemplary diagram of an average image level observed when two images are displayed on one screen of a display panel, FIG. 11 is an exemplary diagram illustrating a peak luminance curve when the brightness setting unit is not in operation according to an embodiment, and FIG. 12 is an exemplary diagram showing a peak luminance curve during operation of the luminance setting unit according to the embodiment, and FIGS. 13 and 14 are diagrams for explaining the relationship between the operation and non-operation of the luminance setting unit according to the embodiment.

As shown in FIG. 10 , a first image and a second image having different average image levels APL may be displayed on one screen of the display panel 150 . Hereinafter, it will be described that the average image level (APL) of the first image is 50% and the average image level (APL) of the second image is 100% as an example.

6 and 11 , when the first image and the second image having different average image levels APL are displayed on one screen of the display panel 150, the luminance setting unit 123 does not operate In the second image having an average image level higher than that of the first image, the luminance may be sharply darkened.

6 and 12, when the luminance setting unit 123 operates when the first image and the second image having different average image levels APL are displayed on one screen of the display panel 150, the second Even if the average image level of the second image is higher than that of the first image, the luminance is not rapidly darkened or there is no difference in luminance between the two images.

6, 13 and 14 , the luminance setting unit 123 does not violate the power consumption standard even when an image having a high average image level (high APL) is displayed on the display panel 150 . It is possible to control the peak luminance curve within a range that does not

In addition, as in the example of FIG. 8, the peak luminance control unit 122 lowers the luminance from 25% of the average image level (APL) to 100%, and in some cases locally improves the peak luminance or normal peak. can However, since the peak luminance control unit 122 basically lowers or raises the luminance in response to the average image level (APL), the problem of non-uniformity in brightness that may occur when two images having different average image levels are displayed on one screen It is difficult to control (cope).

The luminance setting unit 123 is designed to solve the problem of non-uniformity in brightness that may occur when two images having a difference in average image level are expressed on one screen as the purpose and effect of compensating for these shortcomings of the peak luminance control unit 122 . It plays a role in changing the peak luminance curve into a straight line (after artificially increasing the luminance and maintaining it) within the range that does not violate the power consumption standards. To this end, the luminance setting unit 123 generates and outputs a luminance setting signal PCN capable of separately controlling the peak luminance control unit 122 based on the analysis of the input RGB data signal RGB and the user's setting value. can do.

According to the experimental results, even when two images with different average image levels are displayed on one screen, the phenomenon shown in FIG. 11 is not the same even if the luminance setting unit 123 does not operate when the difference between the two is insignificant or when the average image level of either is not high. was not provoked. However, if the difference between the two is large or if one of the average image levels corresponds to a section (high APL) higher than 70%, if the luminance setting unit 123 does not operate, the phenomenon shown in FIG. 11 may be induced.

Therefore, the luminance setting unit 123 may operate when, for example, even if two images having different average image levels are displayed on one screen, the difference between them is insignificant or when either one has a section (high APL) in which the average image level is higher than 70%. can The luminance setting unit 123 may define a section in which the average image level is high (high APL) when the average image level of either side exceeds the internally set average image level. In this case, the average image level defined as a section in which the average image level is high (high APL) may be defined as 70% or more and 100% or less, but is not limited thereto.

As such, when the luminance setting unit 123 operates, two images having different average image levels are displayed on one screen (the difference between the average image levels is intact), but the two images have similar or identical brightness. That is, when the luminance setting unit 123 operates, the luminance control scheme may be changed from the local peak luminance control scheme to the global peak luminance control scheme.

The peak luminance control unit 122 outputs a first luminance control signal PLC1 for local peak luminance control in response to the luminance setting signal PCN output from the luminance setting unit 123 or a second luminance control signal PLC1 for overall peak luminance control. A luminance control signal PLC2 may be output. Therefore, if two images having different average image levels are displayed on one screen and one of them has an average image level of 70% or more and 100% or less, the second luminance control signal PLC2 may be output. However, thereafter, when the average image level is lowered to less than 70% or 60%, the driving condition may be changed so that the first luminance control signal PLC1 is output.

15 is a flowchart illustrating a method of driving a light emitting display device according to an exemplary embodiment of the present invention. Meanwhile, since it can be most widely used to express cinema such as moving pictures on a display panel, a method of driving a light emitting display device will be described below based on this, but the present invention is not limited thereto.

6 to 15 , the light emitting display device according to the embodiment of the present invention periodically determines whether the driving condition is changed to the cinema mode ( S120 ) while the display panel 150 is normally driven ( S110 ). can do. In this case, if the driving condition of the display panel 150 is not changed to the cinema mode (N), normal driving may be performed. However, when the driving condition of the display panel 150 is changed to the cinema mode (cinema mode ON, Y), the peak brightness control unit 122 may be controlled to the cinema mode by driving the brightness setting unit 123 ( S130 ). Meanwhile, since the display panel 150 of the embodiment is based on an organic light emitting diode, the driving time of the luminance setting unit 123 may be preset (Timer Set) when driving in the cinema mode to prevent deterioration thereof.

When the driving condition of the display panel 150 is changed to the cinema mode, images displayed in all regions on the display panel 150 may have similar or identical brightness (because the peak luminance curve is linear). However, as described above, since the display panel 150 of the embodiment is based on an organic light emitting diode, the driving time of the luminance setting unit 123 is already set in order to prevent deterioration thereof, so it is determined whether this time is exceeded (S140) can do. Here, nH for setting the driving time (Timer) of the luminance setting unit 123 may be 3 hours, but this time may be changed by a user's selection.

As a result of the experiment by setting the driving time (Timer) of the luminance setting unit 123 to 3 hours, there was no significant loss in terms of power consumption and deterioration. However, the above experiment corresponds to a simulation focusing on the fact that most of the movie's running time is 3 hours, and the setting value may be changed based on various image conditions for the part related to the driving time.

When the driving time of the luminance setting unit 123 does not exceed the preset time (N), the peak luminance of the display panel 150 may be controlled in the cinema mode. However, when the driving time of the luminance setting unit 123 exceeds the preset time (Y), the display panel 150 may end the cinema mode (cinema mode OFF) (S150) and change to the normal driving mode. . On the other hand, when the cinema mode is terminated (cinema mode OFF), the phrase “Cinema mode is terminated” is displayed on the screen of the display panel 150 and may be automatically terminated, but is not limited thereto.

In the present invention, when there is a section with a high average image level among images displayed on the display panel, the peak luminance curve is changed to a straight line within the range that does not violate the power consumption standard to achieve the same overall screen brightness. can have an effect. In addition, the present invention has the effect of realizing an image without burn-in of the organic light emitting diode and improving the lifespan and display quality of the device. In addition, the present invention has the effect of maximizing the user's satisfaction by giving the customer a choice for compensation for luminance degradation.

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. Therefore, the embodiments described above are illustrative in all respects and should be understood as non-limiting. 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 equivalent concepts should be construed as being included in the scope of the present invention.

110; 120: panel control unit 121: average image level calculation unit
122: peak brightness control unit 123: brightness setting unit
130: data driver 140: scan driver
180: power supply 150: display panel

Claims (10)

a display panel for displaying an image;
an average image level calculator for calculating an average image level for the input image;
a peak luminance control unit for controlling peak luminance for at least one frame based on the average image level; and
When the first image and the second image having different average image levels are displayed on one screen of the display panel, the luminance setting for separately controlling the peak luminance controller so that the brightness of the first image and the second image is the same A light emitting display device comprising a luminance setting unit for outputting a signal. The method of claim 1,
The brightness setting unit
When the average image level of the first image and the second image is different from each other and one of the first image and the second image exceeds the internally set average image level, the peak luminance curve of the peak luminance control unit is converted into a straight line. A light-emitting display device that changes. The method of claim 1,
The brightness setting unit
A light emitting display device for changing the peak luminance curve of the peak luminance control unit into a straight line when the average image level of one of the first image and the second image is 70% or more and 100% or less. The method of claim 1,
The average image level set inside the
A light emitting display device that is variable based on analysis of the input image and a user's setting value. The method of claim 1,
The peak brightness control unit
A light emitting display device for outputting a first luminance control signal for local peak luminance control or a second luminance control signal for overall peak luminance control in response to the luminance setting signal. The method of claim 5,
The peak brightness control unit
When the average image level of one of the first image and the second image is 70% or more and 100% or less, the second luminance control signal is output, and the average image level of one of the first image and the second image is 70 A light emitting display device outputting the first luminance control signal when the % or less than 60%. normally driving the display panel;
controlling a peak luminance curve so that, when the driving condition of the display panel is changed to a cinema mode, the brightness of images displayed in all areas of the display panel is the same; and
and terminating the cinema mode when the cinema mode exceeds a time set therein. The method of claim 7,
The step of controlling the peak luminance curve includes:
A method of driving a light emitting display device for changing the peak luminance curve into a straight line. The method of claim 7,
a driving condition of the display panel is changed to a cinema mode;
When the first image and the second image having different average image levels are displayed on one screen of the display panel, the peak luminance curve is changed into a straight line so that the brightness of the first image and the second image are the same. A method of driving a light emitting display device. The method of claim 9,
When an average image level of one of the first image and the second image is 70% or more and 100% or less, the peak luminance curve is changed into a straight line.

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