This U.S. non-provisional patent application claims priority under 35 U.S.C. § 119 of Korean Patent Application No. 10-2021-0035053, filed on Mar. 18, 2021, the disclosure of which is hereby incorporated by reference in its entirety.
The present disclosure herein relates to a display device.
In general, a display device includes a display panel for displaying an image and a driving circuit for driving the display panel. The display panel includes a plurality of scan lines, a plurality of data lines, and a plurality of pixels. The driving circuit includes a data driving circuit for outputting data signals to the data lines, a scan driving circuit for outputting scan signals for driving the scan lines, and a driving controller for controlling the data driving circuit and the scan driving circuit.
The display device may display an image by outputting a scan signal to a scan line connected to a pixel and providing a data voltage corresponding to an image data to a data line connected to the pixel.
The present disclosure provides a display device with reduced power consumption. The display device may provide an alternative scan driving (ASD) for driving a display panel that has a pentile structure.
According to an embodiment of the inventive concept, a display device includes: a display panel including a plurality of pixels respectively connected to one of a plurality of data lines and at least one of a plurality of scan lines; a data driving circuit configured to drive the plurality of data lines; a scan driving circuit configured to drive the plurality of scan lines; and a driving controller configured to receive an image signal and a control signal, determine an operation mode based on the image signal, generate an image data signal based on the image signal, and provide the image data signal to the data driving circuit, wherein the plurality of pixels include a plurality of color pixels sequentially arranged in a first direction, wherein the plurality of color pixels in a first row are arranged in a first arrangement order, wherein the plurality of color pixels in a second row are arranged in a second arrangement order, wherein the driving controller is further configured to: control the scan driving circuit based on the operation mode being a low frequency mode to sequentially drive a first group of scan lines among the plurality of scan lines to an active level during a first low-frequency frame and sequentially drive a second group of scan lines among the plurality of scan lines to the active level during a second low-frequency frame, and output the image data signal according to the first arrangement order of the plurality of color pixels in the first row during the first low-frequency frame and output the image data signal according to the second arrangement order of the plurality of color pixels in the second row during the second low-frequency frame.
In an embodiment, the plurality of color pixels sequentially arranged in the first direction may include four color pixels, and wherein, in the first row, the first arrangement order of the four color pixels is a first color pixel, a second color pixel, a third color pixel, and the second color pixel.
In an embodiment, the image data signal provided to the four color pixels in the first row during the first low-frequency frame may include a first color signal corresponding to the first color pixel, a second color signal corresponding to the second color pixel, a third color signal corresponding to a third color pixel, and the second color signal corresponding to the second color pixel.
In an embodiment, the plurality of color pixels sequentially arranged in the first direction may include four color pixels, and wherein, in the second row, the second arrangement order of the four color pixels is a third color pixel, a second color pixel, a first color pixel, and the second color pixel.
In an embodiment, the image data signal provided to the four pixels in the second row during the second low-frequency frame may include a third color signal corresponding to the third color pixel, a second color signal corresponding to the second color pixel, a first color signal corresponding to the first color pixel, and the second color signal corresponding to the second color pixel.
In an embodiment, the driving controller may include: an image processor configured to receive the image signal and the control signal, and output a mode signal and the image data signal; and a control signal generation part configured to receive the image signal and the control signal and output a first control signal and a second control signal in response to the mode signal, wherein the data driving circuit may receive the first control signal, and the scan driving circuit receives the second control signal.
In an embodiment, the image processor may include: a mode determination part configured to output the mode signal and a first image signal based on the image signal; an image conversion part configured to convert the first image signal into a second image signal; and an output part configured to convert the second image signal into the image data signal and output the image data signal in response to the mode signal.
In an embodiment, the first image signal may include a first color signal, a second color signal, and a third color signal, wherein the second image signal corresponding to the first row may include the first color signal, the second color signal, the third color signal, and the second color signal, and wherein the second image signal corresponding to the second row may include the third color signal, the second color signal, the first color signal, and the second color signal.
In an embodiment, the display device may further include a lookup table for storing swap information for the first color signal, the second color signal, and the third color signal in the second image signal, wherein the output part may convert the second image signal into the image data signal based on the swap information in the low frequency mode.
In an embodiment, the lookup table may store the swap information for the first color signal, the second color signal, and the third color signal in the second image signal corresponding to a plurality of driving frequencies of the low frequency mode.
In an embodiment, the driving controller may determine that the operation mode is the low frequency mode based on the image signal being a still image signal.
In an embodiment, the driving controller may determine that the operation mode is a normal mode based on the image signal being a video image signal.
In an embodiment, the driving controller may control the scan driving circuit to sequentially drive the plurality of scan lines to an active level in each frame in the normal mode.
In an embodiment, a driving frequency of the low frequency mode may be lower than a driving frequency of the normal mode.
According to an embodiment of the inventive concept, a display device includes: a display panel including a plurality of pixels respectively connected to at least one of a plurality of data lines and at least one of a plurality of scan lines; a data driving circuit configured to drive the plurality of data lines; a scan driving circuit configured to drive the plurality of scan lines; and a driving controller configured to receive an image signal and a control signal, generate an image data signal based on the image signal, and output a mode signal corresponding to the image signal and the image data signal, wherein the plurality of pixels include a plurality of color pixels sequentially arranged in a first direction, wherein the plurality of color pixels in a first row are arranged in a first arrangement order, wherein the plurality of color pixels in a second row are arranged in a second arrangement order, wherein the driving controller controls the scan driving circuit based on the mode signal indicating a low frequency mode to sequentially drive a first group of scan lines among the plurality of scan lines to an active level during a first low-frequency frame and sequentially drive a second group of scan lines among the plurality of scan lines to the active level during a second low-frequency frame, wherein the data driving circuit outputs a data signal according to the first arrangement order of the plurality of color pixels in the first row to the plurality of data lines during the first low-frequency frame, and outputs the data signal according to the second arrangement order of the plurality of color pixels in the second row to the plurality of data lines during the second low-frequency frame.
In an embodiment, the plurality of color pixels sequentially arranged in the first direction may include four color pixels, and wherein, in the first row, the first arrangement order of the four color pixels is a first color pixel, a second color pixel, a third color pixel, and the second color pixel.
In an embodiment, the data signal provided to the four color pixels in the first row during the first low-frequency frame may include a first color signal corresponding to the first color pixel, a second color signal corresponding to the second color pixel, a third color signal corresponding to a third color pixel, and the second color signal corresponding to the second color pixel.
In an embodiment, the plurality of color pixels sequentially arranged in the first direction may include four color pixels, and wherein, in the second row, the second arrangement order of the four color pixels is a third color pixel, a second color pixel, a first color pixel, and the second color pixel.
In an embodiment, the data signal provided to the four pixels in the second row during the second low-frequency frame may include a third color signal corresponding to the third color pixel, a second color signal corresponding to the second color pixel, a first color signal corresponding to the first color pixel, and the second color signal corresponding to the second color pixel.
In an embodiment, the data driving circuit may include: a lookup table configured to store swap information for color signals of the image data signal; a data conversion part configured to convert the image data signal into a first image data signal based on the image data signal and the swap information; and a data driving part configured to receive the first image data signal and provide a plurality of data signals to the plurality of data lines.
The accompanying drawings are included to provide a further understanding of the inventive concept, and are incorporated in and constitute a part of the present disclosure. The drawings illustrate embodiments of the inventive concept and, together with the description, serve to explain principles of the inventive concept. In the drawings:
In the present disclosure, when an element (or region, layer, part, etc.) is referred to as being “on,” “connected to,” or “coupled to” another element, it means that the element may be directly placed on/connected to /coupled to another components, or a third component may be arranged between them.
Like reference numerals refer to like elements. Additionally, in the drawings, the thicknesses, proportions, and dimensions of components may be exaggerated for effective description. “And/or” includes all or any of one or more combinations defined by listed components.
It will be understood that the terms “first,” “second,” etc. are used herein to describe various components, but these components should not be limited by these terms. The above terms are used only to distinguish one component from another. For example, a first component may be referred to as a second component and vice versa without departing from the scope of the inventive concept. The terms of a singular form may include a plural form unless otherwise explicitly specified.
In addition, terms such as “below,” “a lower side,” “on,” “an upper side,” etc. are used to describe a relationship of configurations shown in the drawing. The terms are described as a relative concept based on a direction shown in the drawing, but the inventive concept is not limited thereto.
In various embodiments of the inventive concept, the term “include,” “comprise,” “including,” or “comprising,” specifies a property, a region, a fixed number, a step, a process, an element, and/or a component but does not exclude other properties, regions, fixed numbers, steps, processes, elements, and/or components.
Unless otherwise explicitly defined, terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this inventive concept belongs. In addition, terms defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless interpreted in an ideal or overly formal sense, the terms are explicitly defined herein.
Hereinafter, various embodiments of the inventive concept will be described with reference to the drawings.
Referring to
The display panel 100 includes a scan driving circuit 130, a plurality of pixels PX, a plurality of data lines DL1 to DLm, and a plurality of scan lines SL1 to SLn. Each of the plurality of pixels PX is connected to a corresponding one of the plurality of data lines DL1 to DLm and a corresponding one of the plurality of scan lines SL1 to SLn.
Each of the plurality of scan lines SL1 to SLn extends in a first direction DR1 and is disposed to be spaced apart from each other in a second direction DR2 that crosses the first direction DR1. Each of the plurality of data lines DL1 to DLm extends in the second direction DR2 and is disposed to be spaced apart from each other in the first direction DR1.
The display panel 100 that displays an image may be a liquid crystal display (LCD) panel, an electrophoretic display panel, an organic light emitting diode (OLED) panel, a light emitting diode (LED) panel, an inorganic electro luminescent (EL) display panel, a field emission display (FED) panel, a surface-conduction electron-emitter display (SED) panel, a plasma display panel (PDP), and a cathode ray tube (CRT) display panel.
The driving controller 110 receives an image signal RGB and a control signal CTRL from an external device (not shown) for controlling the display of an image corresponding to the image signal RGB. For example, the control signal CTRL may include at least one synchronization signal and at least one clock signal. The driving controller 110 generates an image data signal DS by processing the image signal RGB according to an operating condition of the display panel 100 and provides the image data signal DS to the data driving circuit 120. The driving controller 110 generates a first control signal DCS and a second control signal SCS based on the control signal CTRL and provides the first control signal DC and the second control signal SCS to the data driving circuit 120 and the scan driving circuit 130, respectively. The first control signal DCS may include a horizontal synchronization start signal, a clock signal, and a line latch signal, and the second control signal SCS may include a vertical synchronization start signal and an output enable signal. In one embodiment, the first control signal DCS may include a mode signal (e.g., a mode signal MD in
The data driving circuit 120 may output grayscale voltages for driving the plurality of data lines DL1 to DLm in response to the first control signal DCS and the image data signal DS that are received from the driving controller 110. In an embodiment, the data driving circuit 120 may be implemented as an integrated circuit (IC) and may be directly mounted on a predetermined area of the display panel 100 or may be mounted on a separate printed circuit board (PCB) in a chip-on-film (COF) to be electrically connected to the display panel 100. In an embodiment, the data driving circuit 120 may be formed on the display panel 100 by the same process as pixel circuits of the pixels PX.
The scan driving circuit 130 drives the plurality of scan lines SL1 to SLn in response to the second control signal SCS that is received from the driving controller 110. In an embodiment, the scan driving circuit 130 may be formed on the display panel 100 by the same process as the pixel circuits of the pixels PX, but the inventive concept of the present disclosure is not limited thereto. For example, the scan driving circuit 130 may be implemented as an integrated circuit (IC) and may be directly mounted on a predetermined area of the display panel 100 or may be mounted on a separate printed circuit board in a chip-on-film (COF) to be electrically connected to the display panel 100.
In an embodiment, the scan driving circuit 130 may sequentially drive the scan lines SL1 to SLn during the normal mode of the display DD. In one embodiment, the scan driving circuit 130 may sequentially drive a first group of scan lines among the scan lines SL1 to SLn in the first frame of the low frequency mode, and sequentially drive a second group of scan lines among the scan lines SL1 to SLn in the second frame of the low frequency mode. The first frame and the second frame of the low frequency mode may appear alternately and repeatedly. The operation of the scanning driving circuit 130 in the low frequency mode will be described later in further detail.
As shown in
The image processor 112 outputs the image data signal DS in response to the image signal RGB and the control signal CTRL. The image processor 112 may generate a mode signal MD in response to the image signal RGB and provide the mode signal MD to the control signal generation part 114.
The control signal generation part 114 generates the first control signal DCS and the second control signal SCS in response to the mode signal MD, the image signal RGB, and the control signal CTRL and outputs the first control signal DCS and the second control signal SCS to the data driving circuit 120 and the scan driving circuit 130, respectively.
Each of the first control signal DCS and the second control signal SCS may include information on an operation mode of the display device DD that is indicated by the mode signal MD.
Referring to
The mode determination part 210 determines a type of the image signal RGB. In an embodiment, the mode determination part 210 may determine whether the image signal RGB is a video image signal that may change in each frame or a still image signal that may not change during multiple frames of a predetermined time. The mode determination part 210 may output the mode signal MD according to the determined type of the image signal RGB.
The image processor 112 may operate in either a normal mode or a low frequency mode according to the mode signal MD that is output from the mode determination part 210. For example, when the image signal RGB is determined to be a video image signal, the image processor 112 may operate in the normal mode. When the image signal RGB is determined to be a still image signal, the image processor 112 may operate in the low frequency mode. The operating frequency of the low frequency mode may be lower than that of the normal mode.
The mode determination part 210 converts the image signal RGB into a first image signal RGB1. During the normal mode, the first image signal RGB1 may be the same as the image signal RGB. During the low frequency mode, the mode determination part 210 may divide the image signal RGB into a plurality of groups, and outputs one of the plurality of groups as the first image signal RGB1 in each frame.
When the mode determination part 210 divides the image signal RGB into a plurality of groups, the number of groups may be determined according to a relationship between the driving frequency of the normal mode and the driving frequency of the low frequency mode.
For example, if the driving frequency of the normal mode is 60 Hz, and the driving frequency of the low frequency mode is 30 Hz, the mode determination part 210 divides the image signal RGB into two groups, that is, a first image signal group and a second image signal group, and alternately outputs the first image signal group and the second image signal group as the first image signal RGB1 in each frame. In an embodiment, the mode determination part 210 outputs the first image signal group as the first image signal RGB1 during a first frame, and outputs the second image signal group as the first image signal RGB1 during a second frame.
The image conversion part 220 may convert the first image signal RGB1 into a second image signal RGB2. In an embodiment, the first image signal RGB1 may include a first color signal, a second color signal, and a third color signal. The second image signal RGB2 may be a signal that is suitable for the pixels PX of the display panel 100 illustrated in
The output part 230 may convert the second image signal RGB2 received from the image conversion part 220 into the image data signal DS in response to the mode signal MD. In an embodiment, the output part 230 may convert the second image signal RGB2 into the image data signal DS based on a swap information SWP stored in the lookup table 240.
Referring to
Four color pixels may be sequentially arranged in the first direction DR1 in each of the pixel rows of the display panel 100. Four color pixels of a first arrangement order may be arranged in each of the first rows of the display panel 100, for example, odd-numbered rows. Four color pixels of a second arrangement order may be arranged in each of the second rows, for example, even-numbered rows.
In the embodiment shown in
In each of the even-numbered rows of the display panel 100 such as the second row, the fourth row, the sixth row, etc., the third color pixel BPX, the second color pixel GPX, the first color pixel RPX, and the second color pixel GPX are repeatedly arranged in the first direction DR1.
The image conversion part 220 illustrated in
Similarly, the image conversion part 220 may convert a first image signal RGB1 that includes a first color signal, a second color signal, and a third color signal corresponding to even-numbered rows into a second image signal RGB2 that includes a third color signal, a second color signal, a first color signal, and a second color signal. For example, the image conversion part 220 may convert a first image signal RGB1 that includes a first color signal, a second color signal, and a third color signal corresponding to the second row into a second image signal RGB2 that includes a third color signal B2, a second color signal G2, a first color signal R2, and a second color signal G2.
The first image signal RGB1 including the first color signal, the second color signal, and the third color signal may be converted into a second image signal RGB2 that is rearranged in an order suitable for the pixel arrangement of the display panel 100 by the conversion operation of the image conversion part 220, and the output part 230 of the image processor 112 that is included in the driving controller 110 may provide the second image signal RGB2 as the image data signal DS to the data driving circuit 120 shown in
Referring to
Referring to
The first low-frequency frame FL1 may include a first low-frequency driving section FD1 and a blank section BPC. The second low-frequency frame FL2 may include a second low-frequency driving section FD2 and a blank section BPC.
In the example shown in
For example, the driving frequency of the low frequency mode may be 30 Hz, and a driving time DT2 of the first and second low-frequency frames FL1 and FL2 in the low frequency mode that corresponds to a period of each of the scan signals S1 to Sn is 33.3 ms.
The first group of the scan signals S, S3, S5, . . . , Sn-1 and the second group of the scan signals S2, S4, S6, . . . , Sn shown in
Referring to
For example, the mode determination part 210 outputs the first image signal group as the first image signal RGB1 in the first low-frequency frame FL1 of the low frequency mode. The first image signal group may include scan signals S1, S3, S5, . . . , Sn-1 to be provided to the pixels PX that are connected to the odd-numbered scan lines SL1, SL3, SL5, . . . , SLn-1.
As described with reference to
Since the image conversion part 220 operates regardless of the operation mode, the image conversion part 220 recognizes that the first image signal RGB1 corresponding to pixels, that is, the first color pixel RPX, the second color pixel GPX, the third color pixel BPX, and the second color pixel GPX, which are connected to the scan line SL3 of the display panel 100, corresponds to an even-numbered row, that is, a second row, and converts the first image signal RGB1 into a second image signal RGB2 including a third color signal B3, a second color signal G3, a first color signal R3, and a second color signal G3.
Therefore, a third color signal B3, a second color signal G3, a first color signal R3, and a second color signal G3 may be respectively provided to the first color pixel RPX, the second color pixel GPX, the third color pixel BPX, and the second color pixel GPX in the third row.
If the third color signal B3 is provided to the first color pixel RPX in the third row, or the first color signal R3 is provided to the third color pixel BPX in the third row, the display quality of the display panel 100 may be deteriorated.
Referring to
Since the image conversion part 220 operates regardless of the operation mode, the image conversion part 220 recognizes that the first image signal RGB1 corresponding to pixels, that is, the third color pixel BPX, the second color pixel GPX, the first color pixel RPX, and the second color pixel GPX, which are connected to the scan line SL2 of the display panel 100, corresponds to an odd-numbered row, that is, a first row, and converts the first image signal RGB1 into a second image signal RGB2 including a first color signal R2, a second color signal G2, a third color signal B2, and a second color signal G2.
Therefore, the first color signal R2, the second color signal G2, the third color signal B2, and the second color signal G2 may be respectively provided to the third color pixel BPX, the second color pixel GPX, the first color pixel RPX, and the second color pixel GPX in the second row.
If the third color signal B4 is provided to the first color pixel RPX in the fourth row, or the first color signal R4 is provided to the third color pixel BPX in the fourth row, the display quality of the display panel 100 may be deteriorated.
The output part 230 illustrated in
Referring to
Also, during the first low-frequency frame FL1 (refer to
Referring to
While the driving frequency of the low frequency mode is 30 Hz, the first color signal R1, the first color signal R3, and the first color signal R5 may be sequentially provided to the data line D1 of the display panel 100, as shown in
The lookup table 240 stores information on color signals that are swapped. In
The output part 230 may swap the third color signals B3, B7, B11, B15, B19, and B23 of the second image signal RGB2 with the first color signals R3, R7, R11, R15, R19, and R23 (not shown) by referring to the lookup table 240. Although not shown in the drawing, the output part 230 may swap the first color signals R3, R7, R11, R15, R19, and R23 of the second image signal RGB2 with the third color signals B3, B7, B11, B15, B19, and B23 by referring to the lookup table 240.
According to the operation of the output part 230 as described above, as shown in
Also as shown in
As shown in
Even if the mode signal MD may indicate the low frequency mode, the output part 230 may selectively perform a swap operation according to a relationship between the driving frequency of the normal mode and the driving frequency of the low frequency mode.
In
First, referring to
During the low frequency mode, the first low-frequency frame FL1 that includes the first low-frequency driving section FD1, the blank section BPC, and the second low-frequency frame FL2 that includes the second low-frequency driving section FD2, and the blank section BPC are repeated.
During the low frequency mode, the data signals D1 and D2 may be provided to the data lines DL1 and DL2 (refer to
Referring to
During the low frequency mode, the first low-frequency driving section FD1, the blank section BPC, the second low-frequency driving section FD2, the blank section BPC, the third low-frequency driving section FD3, and the blank section BPC are repeated.
During the low frequency mode, the data signals D1 and D2 may be provided to the data lines DL1 and DL2 (refer to
Referring to
During the low frequency mode, the first low-frequency driving section FD1, the blank section BPC, the second low-frequency driving section FD2, the blank section BPC, the third low-frequency driving section FD3, the blank section BPC, the fourth low-frequency driving section FD4, and the blank section BPC are repeated.
During the low frequency mode, the data signals D1 and D2 may be provided to the data lines DL1 and DL2 (refer to
For convenience of explanation, the description will be made with reference to the image processor 112 illustrated in
Referring to
The mode determination part 210 determines whether the image signal RGB is a still image signal (step S110).
If the image signal RGB is a still image signal, the mode determination part 210 sets the operation mode of the image processor 112 to a low frequency mode (operation S120).
The mode determination part 210 determines an appropriate driving frequency of the low frequency mode based on the type of the image signal RGB, the type of the display device DD, the type of an application program, and the like (operation S130).
The mode determination part 210 may output a first image signal RGB1 corresponding to the operation mode. The image conversion part 220 converts the first image signal RGB1 into a second image signal RGB2. The second image signal RGB may include a first color signal, a second color signal, and a third color signal.
The output part 230 may refer to the look-up table 240 in response to the mode signal MD and selectively and/or conditionally swap one or more of the first color signal, the second color signal, and the third color signal of the second image signal RGB2 with another color signal (operation S140).
The output part 230 outputs the image data signal DS to the data driving circuit 120 (refer to
If the image signal RGB is not a still image signal, for example, a video image signal, the control may proceed to the operation S150. When the image signal RGB is a video image signal, the mode signal MD may indicate a normal mode, and the output part 230 may output the second image signal RGB2 as the image data signal DS without a swap operation of the color signal(s).
Referring to
The mode determination part 210-1 and the image conversion part 220-1 shown in
In an embodiment, the mode signal MD that is output from the mode determination part 210-1 may be included in the first control signal DCS and provided to the data driving circuit 120. In an embodiment, the mode signal MD that is output from the mode determination part 210-1 may be provided to the data driving circuit 120 through a separate signal line.
The output part 230-1 may convert the second image signal RGB2 received from the image conversion part 220-1 into the image data signal DS.
The output part 230 shown in
Referring to
The data conversion part 310 may receive the image data signal DS and the first control signal DCS from the image processor 112-1 illustrated in
The data conversion part 310 may convert the image data signal DS into a first image data signal DS1 in response to the mode signal MD that is included in the first control signal DCS. The data conversion part 310 may convert the image data signal DS into the first image data signal DS1 based on the swap information SWP stored in the lookup table 320.
The lookup table 320 may store the swap information SWP of a color signal in a manner similar to the lookup table 240 illustrated in
The data driving part 330 may convert the first image data signal DS1 into the data signals D1 to Dm. The data signals D1 to Dm may be provided to the data lines DL1 to DLm as shown in
In an embodiment, the data conversion part 310 may convert the image data signal DS to the first image data signal DS1 based on the swap information SWP from the lookup table 320 when the mode signal MD indicates a low frequency mode. The swap information SWP may include information on a color signal that needs to be changed to another color signal among the color signals in the image data signal DS.
Therefore, in the low frequency mode, the data driving circuit 120 may output data signals D1 to Dm that are suitable for an arrangement order of the first color pixel RPX, the second color pixel GPX, and the third color pixel BPX that are arranged in the display panel 100.
The display device DD may reduce power consumption by alternately driving some of the scan lines SL1 to SLn in each frame. In particular, by converting the data signal to suit the arrangement characteristic of the pixels PX provided in the display panel 100, the present display device DD may prevent the display quality from deteriorating.
Although some embodiments of the inventive concept have been described herein, it is understood that the inventive concept should not be limited to these embodiments, and various changes and modifications may be made by one ordinary skilled in the art within the spirit and scope of the inventive concept as hereinafter claimed.
Number | Date | Country | Kind |
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10-2021-0035053 | Mar 2021 | KR | national |