Display device performing local dimming

Abstract

The present application relates to a display device. The display device includes: a backlight unit including light source rows, each of which includes a light source block; a display panel configured to display an image by transmitting light emitted by the backlight unit; a panel driver configured to drive the display panel; and a backlight driver configured to drive the backlight unit. The backlight driver is configured to perform a vertical direction scanning operation of sequentially selecting light source rows and a horizontal direction sequential driving operation of sequentially driving light source blocks in selected light source rows included in the light source rows.

Description

Technical Field

[0001] Embodiments of the inventive concept relate to a display device, and more particularly, to a display device that performs local dimming. Background Art

[0002] In a display device such as a liquid crystal display (LCD) device, the brightness of the display device is determined by the product of the brightness of the backlight unit and the transmittance of the liquid crystal, depending on the image data. For the purpose of increasing contrast and reducing power consumption, the LCD device may adopt a backlight dimming method. The backlight dimming method controls the backlight brightness and compensates for the image data by analyzing an input image and adjusting the dimming value based on the analysis. For example, in order to reduce power consumption, the backlight dimming method may reduce the backlight brightness by reducing the dimming value (or duty cycle), and may increase the brightness by data compensation. Therefore, the power consumption of the backlight unit may be reduced.

[0003] LED backlight units using light-emitting diodes (LEDs) as light sources have been used for backlight units. Compared with conventional illuminators, LEDs can have the advantages of high brightness and low power consumption. Since the LEDs of LED backlight units allow position-based control, the LEDs can be driven by local dimming. According to the local dimming technology, the LED backlight unit can be divided into light source blocks, and the brightness can be controlled block by block. In addition, in the local dimming method, the local dimming value (or duty cycle) can be determined by analyzing the image data on a block basis, and the image data can be compensated based on the local dimming value. Therefore, the contrast can be increased and the power consumption can be reduced.

[0004] In a conventional display device, in order to reduce image blur or motion blur, when performing local dimming, the light source rows of the backlight unit are sequentially driven row by row. However, the sequential driving of the light source rows may cause a waterfall phenomenon in which a horizontal line image with relatively high brightness or relatively low brightness exists, or a horizontal line image with relatively high brightness or relatively low brightness gradually moves. Summary of the invention

[0005] Some example embodiments provide a display device capable of preventing or reducing a waterfall phenomenon when performing local dimming.

[0006] According to an exemplary embodiment, there is provided a display device including: a backlight unit including a plurality of light source rows, each of the plurality of light source rows including a plurality of light source blocks; a display panel configured to display an image by transmitting light emitted by the backlight unit; a panel driver configured to drive the display panel; and a backlight driver configured to drive the backlight unit. The backlight driver performs a vertical direction scanning operation of sequentially selecting the plurality of light source rows and a horizontal direction sequential driving operation of sequentially driving the plurality of light source blocks included in the selected light source rows among the plurality of light source rows.

[0007] In an exemplary embodiment, in order to perform the vertical direction scanning operation, the backlight driver may sequentially select one of the plurality of light source rows every first time.

[0008] In an exemplary embodiment, the first time may be determined by dividing the frame time by the number of the plurality of light source rows.

[0009] In an exemplary embodiment, in order to perform the horizontal direction sequential driving operation, the backlight driver may sequentially drive one of the plurality of light source blocks included in a selected light source row among the plurality of light source rows every second time.

[0010] In an exemplary embodiment, the second time may be determined by dividing a delay time from a data input time point to an image display time point by the number of the plurality of light source blocks included in each of the plurality of light source rows.

[0011] In an exemplary embodiment, the plurality of light source rows may include a first light source row and a second light source row, and the backlight driver may start the horizontal direction sequential driving operation for the second light source row before completing the horizontal direction sequential driving operation for the first light source row.

[0012] In an exemplary embodiment, each of the plurality of light source rows may include first to M-th light source blocks, where M is an integer greater than 1. To perform a horizontal direction sequential driving operation, the backlight driver may sequentially drive the first to M-th light source blocks included in a selected light source row among the plurality of light source rows in a first horizontal direction from the first light source block to the M-th light source block in an odd-numbered frame, and may sequentially drive the first to M-th light source blocks included in a selected light source row among the plurality of light source rows in a second horizontal direction from the M-th light source block to the first light source block in an even-numbered frame.

[0013] According to an exemplary embodiment, there is provided a display device including: a backlight unit including a plurality of light source rows, each of the plurality of light source rows including a plurality of light source blocks; a display panel configured to display an image by transmitting light emitted by the backlight unit; a panel driver configured to drive the display panel; and a backlight driver configured to drive the backlight unit. The backlight driver divides the backlight unit into a plurality of horizontal regions, and performs a vertical direction scanning operation of sequentially selecting a plurality of light source rows and a horizontal direction sequential driving operation of sequentially driving a plurality of light source blocks included in a selected light source row among the plurality of light source rows in each of the plurality of horizontal regions.

[0014] In an exemplary embodiment, to perform a horizontal direction sequential driving operation in each of the plurality of horizontal regions, the backlight driver may sequentially drive one of the plurality of light source blocks included in a selected light source row among the plurality of light source rows in each of the plurality of horizontal regions per block shift time.

[0015] In an exemplary embodiment, the block shift time may be determined by dividing a delay time from a data input time point to an image display time point by the number of the plurality of light source blocks in each of the plurality of light source rows included in each of the plurality of horizontal areas.

[0016] In an exemplary embodiment, in order to perform a horizontal sequential driving operation in each of a plurality of horizontal regions, the backlight driver may sequentially drive a plurality of light source blocks in a selected light source row among a plurality of light source rows in each of the plurality of horizontal regions in a first horizontal direction in an odd frame, and may sequentially drive a plurality of light source blocks in a selected light source row among a plurality of light source rows in each of the plurality of horizontal regions in a second horizontal direction opposite to the first horizontal direction in an even frame.

[0017] In an exemplary embodiment, the backlight driver may group the plurality of light source rows into an odd-numbered light source row group and an even-numbered light source row group. To perform a horizontal direction sequential driving operation in each of the plurality of horizontal regions, the backlight driver may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows belonging to the odd-numbered light source row group in each of the plurality of horizontal regions in a first horizontal direction, and may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows belonging to the even-numbered light source row group in each of the plurality of horizontal regions in a second horizontal direction opposite to the first horizontal direction.

[0018] In an exemplary embodiment, the backlight driver may group the plurality of light source rows into an odd light source row group and an even light source row group. In order to perform a horizontal direction sequential driving operation in each of the plurality of horizontal regions in an odd frame, the backlight driver may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows belonging to the odd light source row group in each of the plurality of horizontal regions in a first horizontal direction, and may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows belonging to the even light source row group in each of the plurality of horizontal regions in a second horizontal direction opposite to the first horizontal direction. In order to perform a horizontal direction sequential driving operation in each of the plurality of horizontal regions in an even frame, the backlight driver may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows belonging to the odd light source row group in each of the plurality of horizontal regions in the second horizontal direction, and may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows belonging to the even light source row group in each of the plurality of horizontal regions in the first horizontal direction.

[0019] In an exemplary embodiment, the backlight driver may group the (4K+1)th light source row and the (4K+2)th light source row among the plurality of light source rows into a first light source row group, and may group the (4K+3)th light source row and the (4K+4)th light source row among the plurality of light source rows into a second light source row group, where K is an integer greater than 0. In order to perform a horizontal direction sequential driving operation in each of the plurality of horizontal regions, the backlight driver may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows belonging to the first light source row group in each of the plurality of horizontal regions in a first horizontal direction, and may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows belonging to the second light source row group in each of the plurality of horizontal regions in a second horizontal direction opposite to the first horizontal direction.

[0020] In an exemplary embodiment, the backlight driver may group the (4K+1)th light source row and the (4K+2)th light source row among the plurality of light source rows into a first light source row group, and may group the (4K+3)th light source row and the (4K+4)th light source row among the plurality of light source rows into a second light source row group, where K is an integer greater than 0. In order to perform a horizontal direction sequential driving operation in each of the plurality of horizontal regions in an odd-numbered frame, the backlight driver may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows belonging to the first light source row group in each of the plurality of horizontal regions in a first horizontal direction, and may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows belonging to the second light source row group in each of the plurality of horizontal regions in a second horizontal direction opposite to the first horizontal direction. In order to perform a horizontal sequential driving operation in each of multiple horizontal areas in an even frame, the backlight driver can sequentially drive multiple light source blocks in a selected light source row among multiple light source rows belonging to the first light source row group in each of the multiple horizontal areas in the second horizontal direction, and can sequentially drive multiple light source blocks in a selected light source row among multiple light source rows belonging to the second light source row group in each of the multiple horizontal areas in the first horizontal direction.

[0021] In an exemplary embodiment, in order to perform a horizontal direction sequential driving operation in an odd-numbered horizontal region among the plurality of horizontal regions, the backlight driver may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows in the odd-numbered horizontal region in a first horizontal direction. In order to perform a horizontal direction sequential driving operation in an even-numbered horizontal region among the plurality of horizontal regions, the backlight driver may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows in the even-numbered horizontal region in a second horizontal direction opposite to the first horizontal direction.

[0022] In an exemplary embodiment, the horizontal direction sequential driving operation in the odd-numbered horizontal region and the horizontal direction sequential driving operation in the even-numbered horizontal region may have different start time points.

[0023] In an exemplary embodiment, the horizontal direction sequential driving operation in the odd-numbered horizontal region and the horizontal direction sequential driving operation in the even-numbered horizontal region may have different block shift times.

[0024] In an exemplary embodiment, in order to perform a horizontal direction sequential driving operation in an odd-numbered horizontal region among the plurality of horizontal regions, the backlight driver may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows in the odd-numbered horizontal region in a first horizontal direction in an odd-numbered frame, and may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows in the odd-numbered horizontal region in a second horizontal direction opposite to the first horizontal direction in an even-numbered frame. In order to perform a horizontal direction sequential driving operation in an even-numbered horizontal region among the plurality of horizontal regions, the backlight driver may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows in the even-numbered horizontal region in a second horizontal direction in an odd-numbered frame, and may sequentially drive a plurality of light source blocks in a selected light source row among the plurality of light source rows in the even-numbered horizontal region in the first horizontal direction in an even-numbered frame.

[0025] In an exemplary embodiment, the horizontal direction sequential driving operation in the odd-numbered horizontal region and the horizontal direction sequential driving operation in the even-numbered horizontal region may have different start time points or different block shift times.

[0026] Embodiments may relate to a display device. The display device includes: a backlight unit including light source rows, each of which includes a light source block; a display panel configured to display an image by transmitting light emitted by the backlight unit; a panel driver configured to drive the display panel; and a backlight driver configured to drive the backlight unit. The backlight driver is configured to perform a vertical direction scanning operation of sequentially selecting light source rows and a horizontal direction sequential driving operation of sequentially driving light source blocks included in selected light source rows among the light source rows.

[0027] In order to perform the vertical direction scanning operation, the backlight driver is configured to sequentially select one of the light source rows based on the first time period.

[0028] The first time period is determined by dividing the frame time by the number of light source rows.

[0029] In order to perform the horizontal direction sequential driving operation, the backlight driver is configured to sequentially drive one of the light source blocks included in a selected one of the light source rows based on the second time period.

[0030] The second period is determined by dividing a delay time from a data input time point to an image display time point by the number of light source blocks included in each of the light source rows.

[0031] The light source rows include a first light source row and a second light source row, and the backlight driver is configured to start a horizontal direction sequential driving operation for the second light source row before completing a horizontal direction sequential driving operation for the first light source row.

[0032] Each of the light source rows includes first to M-th light source blocks, where M is an integer greater than 1. In order to perform a horizontal direction sequential driving operation, the backlight driver is configured to sequentially drive the first to M-th light source blocks included in a selected light source row among the light source rows in a first horizontal direction from the first light source block to the M-th light source block in an odd-numbered frame, and sequentially drive the first to M-th light source blocks included in the selected light source row among the light source rows in a second horizontal direction from the M-th light source block to the first light source block in an even-numbered frame.

[0033] In an embodiment, a display device includes: a backlight unit including light source rows, each of which includes a light source block; a display panel configured to display an image by transmitting light emitted by the backlight unit; a panel driver configured to drive the display panel; and a backlight driver configured to drive the backlight unit. The backlight driver is configured to divide the backlight unit into horizontal areas, and perform a vertical direction scanning operation of sequentially selecting light source rows and a horizontal direction sequential driving operation of sequentially driving light source blocks included in a selected light source row among the light source rows in each of the horizontal areas.

[0034] To perform a horizontal direction sequential driving operation in each of the horizontal areas, the backlight driver is configured to sequentially drive one of the light source blocks included in a selected one of the light source rows in each of the horizontal areas per block shifted in time.

[0035] The block shift time is determined by dividing a delay time from a data input time point to an image display time point by the number of light source blocks in each of the light source rows included in each of the horizontal areas.

[0036] In order to perform a horizontal sequential driving operation in each of the horizontal areas, the backlight driver is configured to sequentially drive the light source blocks in a selected light source row in each of the horizontal areas in a first horizontal direction in odd frames, and sequentially drive the light source blocks in a selected light source row in each of the horizontal areas in a second horizontal direction opposite to the first horizontal direction in even frames.

[0037] The backlight driver is configured to group the light source rows into an odd-numbered light source row group and an even-numbered light source row group. In order to perform a horizontal direction sequential driving operation in each of the horizontal regions, the backlight driver is configured to sequentially drive the light source blocks in the selected light source rows in the light source rows belonging to the odd-numbered light source row group in each of the horizontal regions in a first horizontal direction, and sequentially drive the light source blocks in the selected light source rows in the light source rows belonging to the even-numbered light source row group in each of the horizontal regions in a second horizontal direction opposite to the first horizontal direction.

[0038] The backlight driver is configured to group the light source rows into an odd-numbered light source row group and an even-numbered light source row group. In order to perform a horizontal direction sequential driving operation in each of the horizontal regions in an odd-numbered frame, the backlight driver is configured to sequentially drive the light source blocks in the selected light source rows in the light source rows belonging to the odd-numbered light source row group in each of the horizontal regions in a first horizontal direction, and sequentially drive the light source blocks in the selected light source rows in the light source rows belonging to the even-numbered light source row group in each of the horizontal regions in a second horizontal direction opposite to the first horizontal direction. In order to perform a horizontal direction sequential driving operation in each of the horizontal regions in an even-numbered frame, the backlight driver is configured to sequentially drive the light source blocks in the selected light source rows in the light source rows belonging to the odd-numbered light source row group in each of the horizontal regions in the second horizontal direction, and sequentially drive the light source blocks in the selected light source rows in the light source rows belonging to the even-numbered light source row group in each of the horizontal regions in the first horizontal direction.

[0039] The backlight driver is configured to group the (4K+1)th light source row and the (4K+2)th light source row among the light source rows into a first light source row group, and to group the (4K+3)th light source row and the (4K+4)th light source row among the light source rows into a second light source row group, where K is an integer greater than 0. In order to perform a horizontal direction sequential driving operation in each of the horizontal regions, the backlight driver is configured to sequentially drive the light source blocks in the selected light source rows among the light source rows belonging to the first light source row group in each of the horizontal regions in a first horizontal direction, and sequentially drive the light source blocks in the selected light source rows among the light source rows belonging to the second light source row group in each of the horizontal regions in a second horizontal direction opposite to the first horizontal direction.

[0040] The backlight driver is configured to group the (4K+1)th light source row and the (4K+2)th light source row among the light source rows into a first light source row group, and group the (4K+3)th light source row and the (4K+4)th light source row among the light source rows into a second light source row group, wherein K is an integer greater than 0. In order to perform a horizontal direction sequential driving operation in each of the horizontal regions in an odd-numbered frame, the backlight driver is configured to sequentially drive the light source blocks in the selected light source rows among the light source rows belonging to the first light source row group in each of the horizontal regions in a first horizontal direction, and sequentially drive the light source blocks in the selected light source rows among the light source rows belonging to the second light source row group in each of the horizontal regions in a second horizontal direction opposite to the first horizontal direction. In order to perform a horizontal direction sequential driving operation in each of the horizontal regions in an even-numbered frame, the backlight driver is configured to sequentially drive the light source blocks in the selected light source rows among the light source rows belonging to the first light source row group in each of the horizontal regions in a second horizontal direction, and sequentially drive the light source blocks in the selected light source rows among the light source rows belonging to the second light source row group in each of the horizontal regions in the first horizontal direction.

[0041] To perform a horizontal direction sequential driving operation in an odd-numbered horizontal area among the horizontal areas, the backlight driver is configured to sequentially drive light source blocks in a selected light source row among the light source rows in the odd-numbered horizontal areas in a first horizontal direction. To perform a horizontal direction sequential driving operation in an even-numbered horizontal area among the horizontal areas, the backlight driver is configured to sequentially drive light source blocks in a selected light source row among the light source rows in the even-numbered horizontal areas in a second horizontal direction opposite to the first horizontal direction.

[0042] The horizontal direction sequential driving operation in the odd-numbered horizontal region and the horizontal direction sequential driving operation in the even-numbered horizontal region have different start time points.

[0043] The horizontal direction sequential driving operation in the odd-numbered horizontal region and the horizontal direction sequential driving operation in the even-numbered horizontal region have different block shift times.

[0044] In order to perform a horizontal direction sequential driving operation in an odd-numbered horizontal area among the horizontal areas, the backlight driver is configured to sequentially drive the light source blocks in a selected light source row among the light source rows in the odd-numbered horizontal areas in a first horizontal direction in an odd-numbered frame, and sequentially drive the light source blocks in a selected light source row among the light source rows in the odd-numbered horizontal areas in a second horizontal direction opposite to the first horizontal direction in an even-numbered frame. In order to perform a horizontal direction sequential driving operation in an even-numbered horizontal area among the horizontal areas, the backlight driver is configured to sequentially drive the light source blocks in a selected light source row among the light source rows in the even-numbered horizontal areas in a second horizontal direction in an odd-numbered frame, and sequentially drive the light source blocks in a selected light source row among the light source rows in the even-numbered horizontal areas in the first horizontal direction in an even-numbered frame.

[0045] The horizontal direction sequential driving operation in the odd-numbered horizontal region and the horizontal direction sequential driving operation in the even-numbered horizontal region have different start time points or different block shift times.

[0046] As described above, the display device according to the exemplary embodiment can perform a vertical direction scanning operation of sequentially selecting light source rows included in the backlight unit, and a horizontal direction sequential driving operation of sequentially driving light source blocks in selected light source rows included in the light source rows. Therefore, a waterfall phenomenon in which a relatively high brightness or relatively low brightness horizontal line image exists or a relatively high brightness or relatively low brightness horizontal line image gradually moves can be prevented or reduced while performing local dimming. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The illustrative, non-limiting exemplary embodiments will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings.

[0048] Figure 1 is a block diagram of a display device according to an exemplary embodiment.

[0049] Figure 2 is a diagram of a backlight unit included in a display device according to an exemplary embodiment.

[0050] Figure 3 is a flowchart of an operation of a display device according to an exemplary embodiment.

[0051] Figure 4 1 is a diagram illustrating a driving timing of a backlight unit of a display device that performs only a vertical direction scanning operation and a driving timing of a backlight unit of a display device that performs both a vertical direction scanning operation and a horizontal direction sequential driving operation according to an exemplary embodiment.

[0052] Figure 5 According to the exemplary embodiment Figure 4A diagram of the operation of the backlight unit of the display device which performs only the vertical direction scanning operation and the operation of the backlight unit of the display device which performs both the vertical direction scanning operation and the horizontal direction sequential driving operation is shown in FIG.

[0053] Figure 6 1 is a diagram of an operation of a backlight unit of a display device that performs only a vertical direction scanning operation and an operation of a backlight unit of a display device that performs both a vertical direction scanning operation and a horizontal direction sequential driving operation according to an exemplary embodiment.

[0054] Figure 7 is a diagram of a driving timing of a backlight unit of a display device that performs only a vertical direction scanning operation and a driving timing of a backlight unit of a display device that performs both a vertical direction scanning operation and a horizontal direction sequential driving operation according to an exemplary embodiment.

[0055] Figure 8 According to the exemplary embodiment Figure 7 FIG. 4 is a diagram showing the influence of the driving timing of the first light source row on the brightness generated by adjacent light source blocks.

[0056] Fig. 9 is a diagram of a driving timing of a backlight unit of a display device that performs only a vertical direction scanning operation and a driving timing of a backlight unit of a display device that performs both a vertical direction scanning operation and a horizontal direction sequential driving operation according to an exemplary embodiment.

[0057] Fig.10 According to the exemplary embodiment Fig. 9 FIG. 4 is a diagram showing the influence of the driving timing of the first light source row on the brightness generated by adjacent light source blocks.

[0058] Fig.11 are diagrams of an image displayed by a display device that performs only a vertical direction scanning operation and an image displayed by a display device that performs both a vertical direction scanning operation and a horizontal direction sequential driving operation according to an exemplary embodiment.

[0059] Fig.12 is a flowchart of an operation of a display device according to an exemplary embodiment.

[0060] Fig.13 The operation of the backlight unit of the display device performing only the vertical direction scanning operation according to the exemplary embodiment and the Fig.12 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0061] Fig.14 is an image displayed by a display device that performs only a vertical direction scanning operation according to an exemplary embodiment and an image displayed by a display device that performs only a vertical direction scanning operation Fig.12 FIG. 1 is a diagram of an image displayed by an operating display device.

[0062] Fig.15 is a flowchart of an operation of a display device according to an exemplary embodiment.

[0063] Fig.16 is performed according to an exemplary embodiment Fig.15 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0064] Fig.17 is a flowchart of an operation of a display device according to an exemplary embodiment.

[0065] Fig.18 is performed according to an exemplary embodiment Fig.17 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0066] Fig.19 is a flowchart of an operation of a display device according to an exemplary embodiment.

[0067] Fig. 20 is performed according to an exemplary embodiment Fig.19 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0068] Fig.21 is performed according to an exemplary embodiment Fig.19 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0069] Fig. 22 is a flowchart of an operation of a display device according to an exemplary embodiment.

[0070] Fig.23 is performed according to an exemplary embodiment Fig. 22 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0071] Fig.24 is a flowchart of an operation of a display device according to an exemplary embodiment.

[0072] Fig.25 is performed according to an exemplary embodiment Fig.24 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0073] Fig.26 is performed according to an exemplary embodiment Fig.24 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0074] Fig. 27 is performed according to an exemplary embodiment Fig.24 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0075] Fig.28 is a block diagram of an electronic device including a display device according to an exemplary embodiment. DETAILED DESCRIPTION

[0076] Hereinafter, embodiments of the present inventive concept will be described in detail with reference to the accompanying drawings.

[0077] Figure 1 is a block diagram illustrating a display apparatus 100 according to an exemplary embodiment. Figure 2 is a diagram of a backlight unit 160 included in a display device according to an exemplary embodiment.

[0078] Reference Figure 1 , the display device 100 may include a display panel 110, a panel driver 120 driving the display panel 110, a backlight unit 160, and a backlight driver 170 driving the backlight unit 160. In an exemplary embodiment, the panel driver 120 may include a data driver 130, a gate driver 140, and a controller 150, wherein the data driver 130 provides a data signal DS to the display panel 110, the gate driver 140 provides a gate signal GS to the display panel 110, and the controller 150 controls the operation of the display device 100.

[0079] The display panel 110 may include data lines, gate lines, and pixels PX coupled to the data lines and the gate lines. The display panel 110 may selectively transmit light emitted by the backlight unit 160 to display an image. In some exemplary embodiments, each pixel PX may include a switching transistor and a liquid crystal capacitor coupled to the switching transistor, and the display panel 110 may be a liquid crystal display (LCD) panel. However, the display panel 110 according to the exemplary embodiment may be any suitable display panel. The display panel 110 may include pixel blocks corresponding to light source blocks of the backlight unit 160, respectively. Here, a group of pixels PX corresponding to one light source block may be referred to as a pixel block. Therefore, here, a pixel block may be a logical unit of pixels PX grouped according to light source blocks, and the pixel blocks may not be physically or structurally distinguished from each other.

[0080] The data driver 130 may generate a data signal DS based on the output image data ODAT and the data control signal DCTRL received from the controller 150, and may provide the data signal DS to the pixel PX through the data line. For example, the data control signal DCTRL may include an output data enable signal, a horizontal start signal, and a load signal. In an exemplary embodiment, the data driver 130 may be implemented using one or more data integrated circuits (ICs). In addition, according to an exemplary embodiment, the data driver 130 may be directly mounted on the display panel 110 in the form of a chip on glass (COG), or may be coupled to the display panel 110 in the form of a chip on film (COF) or a tape carrier package (TCP). In an exemplary embodiment, the data driver 130 may be integrated in the peripheral portion of the display panel 110.

[0081] The gate driver 140 may generate a gate signal GS based on a gate control signal GCTRL received from the controller 150, and may provide the gate signal GS to the pixel PX through a gate line. For example, the gate control signal GCTRL may include a vertical start signal STV and a gate clock signal. In some exemplary embodiments, the gate driver 140 may be implemented as an amorphous silicon gate (ASG) driver integrated in a peripheral portion of the display panel 110. In other exemplary embodiments, the gate driver 140 may be implemented using one or more gate ICs. In addition, according to some exemplary embodiments, the gate driver 140 may be directly mounted on the display panel 110 in the form of a COG, or may be coupled to the display panel 110 in the form of a COF or a TCP.

[0082] The controller 150 (e.g., a timing controller) may receive input image data IDAT and a control signal CTRL from an external host (e.g., a graphics processing unit (GPU) or a graphics card). For example, the input image data IDAT may be RGB image data including red image data, green image data, and blue image data. In addition, for example, the control signal CTRL may include a master clock signal, a data enable signal, a vertical synchronization signal, a horizontal synchronization signal, and the like. The controller 150 may generate output image data ODAT, a data control signal DCTRL, a gate control signal GCTRL, and a backlight control signal BCTRL based on the input image data IDAT and the control signal CTRL. In some exemplary embodiments, the controller 150 may generate output image data ODAT by performing an image enhancement operation, a brightness non-uniformity correction operation, a dynamic capacitance compensation (DCC) operation, and the like on the input image data IDAT. The controller 150 may control the operation of the data driver 130 by providing the output image data ODAT and the data control signal DCTRL to the data driver 130 , may control the operation of the gate driver 140 by providing the gate control signal GCTRL to the gate driver 140 , and may control the operation of the backlight driver 170 by providing the backlight control signal BCTRL to the backlight driver 170 .

[0083] The backlight unit 160 may include light source rows, and each light source row may include a light source block. Figure 2 As shown in , the backlight unit 160 may include N light source rows, or a first light source row LSR1, a second light source row LSR2 ... to an N-th light source row LSRN, where N is an integer greater than 1. In addition, each of the first light source row LSR1, the second light source row LSR2 ... to the N-th light source row LSRN may include M light source blocks, or a first light source block to an M-th light source block B11, B12 ... B1M, B21, B22 ... B2M ... BN1, BN2 ... BNM, where M is an integer greater than 1. Therefore, the backlight unit 160 may include N×M light source blocks B11, B12 ... B1M, B21, B22 ... B2M ... BN1, BN2 ... BNM. The N×M light source blocks B11, B12 ... B1M, B21, B22 ... B2M ... BN1, BN2 ... BNM may be driven independently of each other. In some exemplary embodiments, the backlight unit 160 may be a direct-type light emitting diode (LED) backlight unit using an LED as a light source.

[0084] The backlight driver 170 may drive the backlight unit 160 based on the backlight control signal BCTRL received from the controller 150. In an exemplary embodiment, the backlight control signal BCTRL may include a dimming signal SDIM indicating that local dimming is to be performed, and the backlight driver 170 may perform local dimming in response to the dimming signal SDIM. In some exemplary embodiments, the dimming signal SDIM may also indicate a duty cycle of a light source block driving signal (e.g., a pulse width modulation (PWM) signal) to be applied to the N×M light source blocks B11, B12…B1M, B21, B22…B2M…BN1, BN2…BNM included in the backlight unit 160, respectively. For example, the controller 150 may determine the duty cycle of the light source block driving signal by analyzing the input image data IDAT of the pixel blocks respectively corresponding to the N×M light source blocks B11, B12…B1M, B21, B22…B2M…BN1, BN2…BNM of the display panel 110, and may provide the dimming signal SDIM representing the determined duty cycle to the backlight driver 170. In an example, the controller 150 may determine the duty cycle of the light source block driving signal for each light source block according to the representative grayscale value (e.g., the maximum grayscale value and / or the average grayscale value) of the pixel block corresponding to each light source block. The backlight driver 170 can perform local dimming by driving N×M light source blocks B11, B12…B1M, B21, B22…B2M…BN1, BN2…BNM with a determined duty cycle represented by the dimming signal SDIM, or can perform local dimming by driving the N×M light source blocks B11, B12…B1M, B21, B22…B2M…BN1, BN2…BNM for a duration corresponding to the determined duty cycle.

[0085] In order to perform local dimming, the backlight driver 170 can sequentially drive the N×M light source blocks B11, B12…B1M, B21, B22…B2M…BN1, BN2…BNM not only in the vertical direction (e.g., in the direction of each data line) but also in the horizontal direction (e.g., in the direction of each gate line). Therefore, the driving start time points of the N×M light source blocks B11, B12…B1M, B21, B22…B2M…BN1, BN2…BNM can be sequentially determined in the vertical direction and the horizontal direction, and the driving duration (e.g., the driving time period or time length) of the N×M light source blocks B11, B12…B1M, B21, B22…B2M…BN1, BN2…BNM can be determined by the determined duty cycle represented by the dimming signal SDIM. In an exemplary embodiment, in order to sequentially drive N×M light source blocks B11, B12...B1M, B21, B22...B2M...BN1, BN2...BNM in the vertical and horizontal directions, the backlight driver 170 performs a vertical direction scanning operation and a horizontal direction sequential driving operation, wherein the vertical direction scanning operation sequentially selects light source rows LSR1, LSR2,..., LSRN, and the horizontal direction sequential driving operation sequentially drives the light source blocks B11, B12...B1M included in each selected light source row (for example, the first light source row LSR1).

[0086] In a conventional display device, the light source rows of the backlight unit may be sequentially driven to perform local dimming, and the light source blocks in each light source row may be driven substantially at the same time. Since the light source blocks in each light source row are driven substantially at the same time, the brightness of each light source block may be affected by the brightness of the adjacent light source blocks. Specifically, when local dimming is performed in a conventional display device, a waterfall phenomenon may occur in which a horizontal line image of relatively high brightness or relatively low brightness or a horizontal line image of relatively high brightness or relatively low brightness gradually moves due to the sequential driving of the light source rows. However, in the display device 100 according to an exemplary embodiment, the N×M light source blocks B11, B12…B1M, B21, B22…B2M…BN1, BN2…BNM of the backlight unit 160 are sequentially driven in the vertical direction and the horizontal direction through a vertical direction scanning operation and a horizontal direction sequential driving operation. Therefore, the influence of the brightness of the adjacent light source blocks on the brightness of each light source block can be reduced, and the waterfall phenomenon can be prevented or reduced while performing local dimming.

[0087] Figure 3 is a flowchart of an operation of a display device according to an exemplary embodiment. Figure 41 is a diagram illustrating a driving timing of a backlight unit of a display device that performs only a vertical direction scanning operation and a driving timing of a backlight unit of a display device that performs both a vertical direction scanning operation and a horizontal direction sequential driving operation according to an exemplary embodiment. Figure 5 According to the exemplary embodiment Figure 4 A diagram of the operation of the backlight unit of the display device which performs only the vertical direction scanning operation and the operation of the backlight unit of the display device which performs both the vertical direction scanning operation and the horizontal direction sequential driving operation is shown in FIG. Figure 6 1 is a diagram of an operation of a backlight unit of a display device that performs only a vertical direction scanning operation and an operation of a backlight unit of a display device that performs both a vertical direction scanning operation and a horizontal direction sequential driving operation according to an exemplary embodiment. Figure 7 is a diagram of a driving timing of a backlight unit of a display device that performs only a vertical direction scanning operation and a driving timing of a backlight unit of a display device that performs both a vertical direction scanning operation and a horizontal direction sequential driving operation according to an exemplary embodiment. Figure 8 According to the exemplary embodiment Figure 7 FIG. 4 is a diagram showing the influence of brightness caused by adjacent light source blocks of a first light source row on the driving timing of FIG. Fig. 9 is a diagram of a driving timing of a backlight unit of a display device that performs only a vertical direction scanning operation and a driving timing of a backlight unit of a display device that performs both a vertical direction scanning operation and a horizontal direction sequential driving operation according to an exemplary embodiment. Fig.10 According to the exemplary embodiment Fig. 9 FIG. 4 is a diagram showing the influence of brightness caused by adjacent light source blocks of a first light source row on the driving timing of FIG. Fig.11 are diagrams of an image displayed by a display device that performs only a vertical direction scanning operation and an image displayed by a display device that performs both a vertical direction scanning operation and a horizontal direction sequential driving operation according to an exemplary embodiment.

[0088] Reference Figure 1 and Figure 3In operation S210, the panel driver 120 of the display device 100 may receive the input image data IDAT, and in operation S230, the panel driver 120 of the display device 100 may drive the display panel 110 based on the input image data IDAT. For example, the controller 150 may provide the output image data ODAT corresponding to the input image data IDAT to the data driver 130, the data driver 130 may provide the data signal DS corresponding to the output image data ODAT to the display panel 110, and the gate driver 140 may provide the gate signal GS to the display panel 110. The transmittance or transmittance factor of the pixel PX of the display panel 110 may be adjusted based on the data signal DS and the gate signal GS. In addition, the controller 150 may provide the dimming signal SDIM indicating that local dimming is to be performed to the backlight driver 170.

[0089] In operation S250, the backlight driver 170 may perform a vertical direction scanning operation and a horizontal direction sequential driving operation for the backlight unit 160 in response to the dimming signal SDIM. The vertical direction scanning operation may be an operation of sequentially selecting light source rows included in the backlight unit 160 in a vertical direction (e.g., a direction of each data line), and the horizontal direction sequential driving operation may be an operation of sequentially driving light source blocks included in each light source row in a horizontal direction (e.g., a direction of each gate line).

[0090] For example, Figure 4 As shown in the driving timing 310 of FIG. 1 , the display device that performs only the vertical direction scanning operation V-SCAN can sequentially drive the light source rows LSR1, LSR2, LSR3, ..., and the light source blocks included in each light source row (e.g., the first light source row LSR1) can be driven substantially at the same time (in the drawings, the reference symbol 'ON' represents the driving of the light source row and / or the light source block). However, as Figure 4 As shown in the driving timing 320, the display device 100 according to the exemplary embodiment can perform a vertical direction scanning operation V-SCAN of sequentially selecting light source rows LSR1, LSR2, LSR3... and a horizontal direction sequential driving operation H-SD of sequentially driving the light source blocks (e.g., B11, B12, B13...B1M) included in each selected light source row (e.g., the first light source row LSR1).

[0091] In order to perform the vertical direction scanning operation V-SCAN, the backlight driver 170 may sequentially select one of the light source rows LSR1, LSR2, LSR3, ... every first time T1 (e.g., based on a first time period). The first time T1 is a first time period or a time length from a time point. A time point is a specific time point, for example, a specific time point when a light source row is selected. For example, the backlight driver 170 may select a second light source row LSR2 after a first time T1 has passed from a time point when the first light source row LSR1 is selected, and may select a third light source row LSR3 after a first time T1 has passed from a time point when the second light source row LSR2 is selected. In some exemplary embodiments, the first time T1 may be determined by dividing a frame time FT by the number of light source rows LSR1, LSR2, LSR3, ... The frame time FT is a time period or a time length of a frame. For example, when the display device 100 operates at a frame rate of approximately 120 Hz and the backlight unit 160 includes 16 light source rows LSR1, LSR2, LSR3...LSR16 (not shown), the frame time FT may be approximately 8.3 ms (=1 / 120 ms) and the first time T1 may be approximately 0.52 ms (=8.3 / 16 ms).

[0092] In addition, in order to perform the horizontal sequential driving operation H-SD, the backlight driver 170 may sequentially drive one of the light source blocks (e.g., light source blocks B11, B12, B13 ... B1M) included in the selected light source row (e.g., the first light source row LSR1) every second time T2. The second time T2 is a second time period or time length from a time point. For example, when the first light source row LSR1 is selected, the light source blocks B11, B12, B13 ... B1M of the first light source row LSR1 may be sequentially driven every second time T2. In addition, when the second light source row LSR2 is selected after a first time T1 has passed from a time point when the first light source row LSR1 is selected, the light source blocks B21, B22, B23 ... B2M of the second light source row LSR2 may be sequentially driven every second time T2. In some exemplary embodiments, as Figure 4As shown in , before the horizontal direction sequential driving operation H-SD for the first light source row LSR1 is completed, the second light source row LSR2 can be selected by the vertical direction scanning operation V-SCAN, and the horizontal direction sequential driving operation H-SD for the selected second light source row LSR2 can be started. In addition, when the third light source row LSR3 is selected after the first time T1 has passed from the time point when the second light source row LSR2 is selected, the light source blocks B31, B32, B33...B3M of the third light source row LSR3 can be sequentially driven every second time T2. In some exemplary embodiments, the second time T2 can be determined based on the delay time LT (i.e., the time period from the data input time point when the input image data IDAT is input (or the time point when the vertical start signal STV is generated) to the image display time point when the image corresponding to the input image data IDAT is displayed). The delay time LT can be predetermined by the standard or specification of the display device 100. For example, the second time T2 may be determined by dividing the delay time LT by the number of light source blocks (e.g., light source blocks B11, B12, B13 ... B1M) included in each light source row (e.g., the first light source row LSR1). In the example, when the delay time LT is about 2 ms and each light source row includes 40 light source blocks, the second time T2 may be about 50 μs (= 2000 / 40 μs). In this case, the second light source block B12 of the first light source row LSR1 may be driven after a second time T2 of about 50 μs has passed since the time point when the first light source block B11 of the first light source row LSR1 is started to be driven. In addition, the third light source block B13 of the first light source row LSR1 may be driven after a second time T2 of about 50 μs has passed since the time point when the second light source block B12 of the first light source row LSR1 is started to be driven. The second time T2, which is the interval time of the driving start time point of the light source blocks in each light source row, may be referred to as a block shift time or a phase shift time.

[0093] In the display device that performs only the vertical direction scanning operation V-SCAN and the display device 100 that performs the vertical direction scanning operation V-SCAN and the horizontal direction sequential driving operation H-SD, the backlight unit 160 may be driven by Figure 4 The driving timings 310 and 320 are as follows Figure 5 That is, in the display device operated according to the driving timing 310, the first light source row LSR1 may emit light, and after the first time T1, the second light source row LSR2 may emit light. Then, after the first time T1, the third light source row LSR3 may emit light.

[0094] However, in the display device 100 operated according to the driving timing 320, the first light source block B11 of the first light source row LSR1 may be made to start emitting light. After the second time T2, the second light source block B12 of the first light source row LSR1 may be made to start emitting light. After the second time T2, the third light source block B13 of the first light source row LSR1 may be made to start emitting light. After the second time T2, the fourth light source block B14 of the first light source row LSR1 may be made to start emitting light.

[0095] Then, the first light source block B21 of the second light source row LSR2 and the fifth light source block B15 of the first light source row LSR1 may start to emit light. After the second time T2, the second light source block B22 of the second light source row LSR2 and the sixth light source block B16 of the first light source row LSR1 may start to emit light. After the second time T2, the third light source block B23 of the second light source row LSR2 and the seventh light source block B17 of the first light source row LSR1 may start to emit light. After the second time T2, the fourth light source block B24 of the second light source row LSR2 and the eighth light source block B18 of the first light source row LSR1 may start to emit light.

[0096] Then, the first light source block B31 of the third light source row LSR3, the fifth light source block B25 of the second light source row LSR2, and the ninth light source block B19 of the first light source row LSR1 may start to emit light. After the second time T2, the second light source block B32 of the third light source row LSR3 and the sixth light source block B26 of the second light source row LSR2 may start to emit light. After the second time T2, the third light source block B33 of the third light source row LSR3 and the seventh light source block B27 of the second light source row LSR2 may start to emit light. After the second time T2, the fourth light source block B34 of the third light source row LSR3 and the eighth light source block B28 of the second light source row LSR2 may start to emit light.

[0097] The operation of the display device 100 that performs only the vertical direction scanning operation V-SCAN and the display device 100 that performs the vertical direction scanning operation V-SCAN and the horizontal direction sequential driving operation H-SD may be as follows: Figure 6 That is, in a display device that performs only the vertical scanning operation V-SCAN (such as Figure 6 315 ), the light source blocks B1 to B9 of the first light source row LSR1 may emit light substantially at the same time, and after the first time T1, the light source blocks B1 to B9 of the second light source row LSR2 may emit light substantially at the same time.

[0098] However, in the display device 100 that performs the vertical scanning operation V-SCAN and the horizontal sequential driving operation H-SD (eg, Figure 6325 ), the light source rows LSR1, LSR2, ... may be sequentially selected every first time T1, and the light source blocks B1 to B9 of each of the sequentially selected light source rows LSR1, LSR2, ... may be sequentially driven every second time T2.

[0099] Compared with the brightness influence of adjacent light source blocks in a display device that only performs the vertical scanning operation V-SCAN on each light source block, the brightness influence of adjacent light source blocks in the display device 100 on each light source block can be reduced. Figure 8 Shown according to Figure 7 The driving timings 330 and 340 shown in FIG. 3 affect the brightness of each light source block in the first light source row LSR1 . Fig.10 Shown according to Fig. 9 The adjacent light source blocks in the display device operated by the driving timings 350 and 360 shown in FIG. 1 affect the brightness of each light source block in the first light source row LSR1. Figure 8 and Fig.10 In the embodiment, each of the light source blocks B11 to B19 of the first light source row LSR1 can be equally divided into four regions along the vertical direction, and the brightness influence of the adjacent light source blocks at the equally divided four regions of each light source block B11 to B19 can be expressed as a numerical value. Figure 8 and Fig.10 The values ​​of the brightness influence of adjacent light source blocks shown in may be relative values ​​and may not have specific units or measurements. For example, Figure 8 and Fig.10 The value of the brightness influence of the adjacent light source blocks shown in can be determined by assuming that the brightness of a light emitting light source block is 1.

[0100] For example, Figure 7 As shown in the driving timing 330, when the light source rows LSR1, LSR2, LSR3, ... sequentially emit light and the light emission time of each light source row (for example, the first light source row LSR1) corresponds to half of the first time T1, as shown in FIG. Figure 8 As shown in FIG. 335 , the lower half area of ​​the light source blocks B11 to B19 of the first light source row LSR1 may be affected by the brightness within a range from about 1.75 to about 2.5. Figure 7 As shown in the driving timing 340, when the light source rows LSR1, LSR2, LSR3, ... are sequentially selected and the light source blocks B11 to B19 in each selected light source row (for example, the first light source row LSR1) are sequentially driven, as shown in FIG. Figure 8As shown in FIG. 345 , the lower half area of ​​the light source blocks B11 to B19 of the first light source row LSR1 may be affected by the brightness influence in the range from about 0 to about 1.5. Therefore, compared with a display device that performs only the vertical direction scanning operation V-SCAN, the brightness influence of the adjacent light source blocks on each light source block in the display device 100 can be reduced.

[0101] In addition, for example, Fig. 9 As shown in the driving timing 350, when the light source rows LSR1, LSR2, LSR3, ... sequentially emit light and the light emission time of each light source row (for example, the first light source row LSR1) corresponds to twice the first time T1, as shown in FIG. Fig.10 As shown in FIG. 355 , the divided areas of the light source blocks B11 to B19 of the first light source row LSR1 may be affected by the brightness within a range from about 1.75 to about 3.85. Fig. 9 As shown in the driving timing 360, in the case where light source rows LSR1, LSR2, LSR3, ... are sequentially selected and the light source blocks B11 to B19 in each selected light source row (for example, the first light source row LSR1) are sequentially driven, as shown in FIG. Fig.10 As shown in FIG. 365 , the divided areas of the light source blocks B11 to B19 of the first light source row LSR1 may be affected by the brightness influence in the range from about 0 to about 3.05. Therefore, compared with the display device that performs only the vertical direction scanning operation V-SCAN, the brightness influence of the adjacent light source blocks on each light source block in the display device 100 according to the exemplary embodiment can be reduced.

[0102] like Fig.11 As shown in , in the image 410 displayed at the display device that performs only the vertical direction scanning operation V-SCAN, a waterfall phenomenon may occur in which a horizontal line image of relatively high brightness or relatively low brightness exists or a horizontal line image of relatively high brightness or relatively low brightness gradually moves. However, by reducing the brightness influence of adjacent light source blocks, in the image 430 displayed at the display device 100 that performs the vertical direction scanning operation V-SCAN and the horizontal direction sequential driving operation H-SD, the waterfall phenomenon can be prevented or reduced.

[0103] Fig.12 is a flowchart of an operation of a display device according to an exemplary embodiment. Fig.13 The operation of the backlight unit of the display device performing only the vertical direction scanning operation according to the exemplary embodiment and the Fig.12 FIG. 1 is a diagram of an operation of a backlight unit of a display device. Fig.14 is an image displayed by a display device that performs only a vertical direction scanning operation according to an exemplary embodiment and an image displayed by a display device that performs only a vertical direction scanning operation Fig.12 FIG. 1 is a diagram of an image displayed by an operating display device.

[0104] Reference Figure 1 and Fig.12 In operation S510, the panel driver 120 of the display device 100 may receive input image data IDAT, and in operation S530, the panel driver 120 of the display device 100 may drive the display panel 110 based on the input image data IDAT.

[0105] In operation S550: odd frames and operation S580, the backlight driver 170 may perform a vertical direction scanning operation in the odd frames and a horizontal direction sequential driving operation in the first horizontal direction; and in operation S550: even frames and operation S590, the backlight driver 170 may perform a vertical direction scanning operation in the even frames and a horizontal direction sequential driving operation in a second horizontal direction opposite to the first horizontal direction. In some exemplary embodiments, each light source row of the backlight unit 160 may include a first light source block to an M-th light source block, the horizontal direction sequential driving operation in the first horizontal direction may be an operation of sequentially driving the first light source block to the M-th light source block in an order from the first light source block to the M-th light source block, and the horizontal direction sequential driving operation in the second horizontal direction may be an operation of sequentially driving the first light source block to the M-th light source block in an order from the M-th light source block to the first light source block.

[0106] For example, Fig.13 As shown in FIG. 610 , in a display device that performs only the vertical direction scanning operation V-SCAN, the light source rows LSR1, LSR2, . . . can emit light sequentially, and the light emission operation in the odd-numbered frames can be the same as the light emission operation in the even-numbered frames. Fig.12 In the display device 100 of the operation of FIG. 1 , the light source blocks B11 to B19 of each light source row (e.g., the first light source row LSR1) may sequentially emit light in the first horizontal direction from the leftmost light source block B11 in an odd frame. The vertical direction scanning operation V-SCAN and the horizontal direction sequential driving operation H-SD in the first horizontal direction in the odd frame may be expressed as Fig.13 In addition, when executing Fig.12 In the display device 100 of the operation of FIG. 1 , the light source blocks B11 to B19 of each light source row (e.g., the first light source row LSR1) may sequentially emit light from the rightmost light source block B19 in the second horizontal direction in an even frame. The vertical direction scanning operation V-SCAN and the horizontal direction sequential driving operation H-SD in the second horizontal direction in the even frame may be expressed as Fig.13 Figure 650 in FIG. That is, when executing Fig.12In the display device 100 in which the horizontal sequential driving operation H-SD is operated, the direction of the horizontal direction sequential driving operation H-SD may be reversed in odd-numbered frames and even-numbered frames, and this operation may be referred to as a frame inversion operation.

[0107] like Fig.14 As shown in , in the image 710 displayed at the display device that performs only the vertical direction scanning operation V-SCAN, a waterfall phenomenon in which a horizontal line image of relatively high brightness or relatively low brightness exists or a horizontal line image of relatively high brightness or relatively low brightness gradually moves may occur. However, in the image 730 displayed at the display device 100 that performs the vertical direction scanning operation V-SCAN, the horizontal direction sequential driving operation H-SD, and the frame inversion operation, the waterfall phenomenon can be prevented or reduced.

[0108] Fig.15 is a flowchart of an operation of a display device according to an exemplary embodiment. Fig.16 is performed according to an exemplary embodiment Fig.15 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0109] Reference Figure 1 and Fig.15 In operation S810, the panel driver 120 of the display device 100 may receive input image data IDAT, and in operation S830, the panel driver 120 of the display device 100 may drive the display panel 110 based on the input image data IDAT.

[0110] In operation S850, the backlight driver 170 may divide the backlight unit 160 into horizontal regions, and in operation S870, the backlight driver 170 may perform a vertical direction scanning operation of sequentially selecting a light source row of the backlight unit 160 in each horizontal region and a horizontal direction sequential driving operation of sequentially driving the light source blocks included in the selected light source row. Here, each horizontal region may include two or more continuous light source columns of the backlight unit 160.

[0111] For example, Fig.16As shown in FIG. 900 , the backlight driver 170 may divide the backlight unit 160 into a first horizontal region HR1, a second horizontal region HR2, and a third horizontal region HR3, wherein the first horizontal region HR1 includes a first light source block B1, a second light source block B2, and a third light source block B3 of each light source row, the second horizontal region HR2 includes a fourth light source block B4, a fifth light source block B5, and a sixth light source block B6 of each light source row, and the third horizontal region HR3 includes a seventh light source block B7, an eighth light source block B8, and a ninth light source block B9 of each light source row. For the first horizontal region HR1, the backlight driver 170 may perform a vertical direction scanning operation of sequentially selecting light source rows, and a horizontal direction sequential driving operation of sequentially driving the first light source block B1, the second light source block B2, and the third light source block B3 in each of the parts LSR11, LSR21, ... of the sequentially selected light source rows included in the first horizontal region HR1. For the second horizontal region HR2, the backlight driver 170 may perform a vertical direction scanning operation of sequentially selecting light source rows, and a horizontal direction sequential driving operation of sequentially driving the fourth light source block B4, the fifth light source block B5, and the sixth light source block B6 in each of the parts LSR12, LSR22, ... of the sequentially selected light source rows included in the second horizontal region HR2. For the third horizontal region HR3, the backlight driver 170 may perform a vertical direction scanning operation of sequentially selecting light source rows, and a horizontal direction sequential driving operation of sequentially driving the seventh light source block B7, the eighth light source block B8, and the ninth light source block B9 in each of the parts LSR13, LSR23, ... of the sequentially selected light source rows included in the third horizontal region HR3.

[0112] Fig.16 An example is shown in which each light source row includes nine light source blocks B1 to B9, and each horizontal region HR1, HR2, and HR3 includes three light source columns, but the number of light source blocks B1 to B9 in each light source row may be different, the number of horizontal regions HR1, HR2, and HR3 may be different, and the number of light source columns in each horizontal region HR1, HR2, and HR3 may be different.

[0113] As mentioned above Figures 3 to 11 As mentioned above, in the implementation Figure 3 In the display device 100 of the operation shown in , the second time T2 (i.e., the block shift time or the phase shift time) which is the interval time of the driving start time point of the light source blocks in each light source row can be determined by dividing the delay time LT by the number of light source blocks in each light source row. Therefore, as the number of light source blocks in each light source row increases, the block shift time can be reduced. If the block shift time is reduced, the brightness influence of the adjacent light source blocks on each light source block can be increased.

[0114] However, in the implementation Fig.15 In the display device 100 of the operation shown in , the backlight unit 160 can be divided into horizontal regions HR1, HR2 and HR3, and in each horizontal region (e.g., the first horizontal region HR1), a horizontal direction sequential driving operation of sequentially driving the light source blocks (e.g., light source blocks B1, B2 and B3) included in the selected light source row (e.g., the first light source row LSR11) can be performed. Therefore, the block shift time can be determined by dividing the delay time LT by the number of light source blocks (e.g., light source blocks B1, B2 and B3) in the portion of each light source row included in each horizontal region (e.g., the first horizontal region HR1). That is, performing Fig.15 The block shift time in the display device 100 of the operation shown in FIG. 1 may correspond to the time of performing Figure 3 The block shift time in the display device 100 of the operation shown in FIG. 1 is the product of the number of horizontal regions HR1, HR2, and HR3. Fig.15 In the display device 100 operating as shown in FIG. 1 , the influence of adjacent light source blocks on the brightness of each light source block can be reduced, and a waterfall phenomenon can be prevented or reduced while performing local dimming.

[0115] Fig.17 is a flowchart of an operation of a display device according to an exemplary embodiment. Fig.18 is performed according to an exemplary embodiment Fig.17 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0116] Reference Figure 1 and Fig.17 In operation S1010, the panel driver 120 of the display device 100 may receive input image data IDAT, and in operation S1030, the panel driver 120 of the display device 100 may drive the display panel 110 based on the input image data IDAT.

[0117] In operation S1050, the backlight driver 170 may divide the backlight unit 160 into horizontal regions, and may perform a vertical direction scanning operation and a horizontal direction sequential driving operation in each horizontal region. Fig.15 The operation of the display device 100 shown in FIG. 1 is compared to that performed by Fig.17 The display device 100 of the operation shown in FIG. 100 can also perform a frame inversion operation. Therefore, in order to perform a horizontal direction sequential driving operation in each horizontal region, in operation S1070: odd frames and in operation S1080, perform Fig.17The backlight driver 170 of the display device 100 shown in the operation can sequentially drive the light source blocks in the selected light source row in the horizontal area in the first horizontal direction in the odd frames, and in operation S1070: even frames and operation S1090, the backlight driver 170 can sequentially drive the light source blocks in the selected light source row in the horizontal area in the second horizontal direction opposite to the first horizontal direction in the even frames.

[0118] For example, Fig.18 As shown in FIG. 1110 , in each of the horizontal regions HR1 , HR2 , and HR3 , a vertical direction scanning operation and a horizontal direction sequential driving operation in a first horizontal direction from the left light source block to the right light source block may be performed in odd frames. Fig.18 As shown in FIG. 1130 , in each of the horizontal regions HR1 , HR2 , and HR3 , a vertical direction scanning operation and a horizontal direction sequential driving operation in a second horizontal direction from the right light source block to the left light source block may be performed in an even frame. Fig.17 In the display device 100 of the operation shown in , a frame inversion operation can also be performed, and the waterfall phenomenon can be further prevented or reduced while performing local dimming.

[0119] Fig.19 is a flowchart of an operation of a display device according to an exemplary embodiment. Fig. 20 is performed according to an exemplary embodiment Fig.19 FIG. 1 is a diagram of an operation of a backlight unit of a display device. Fig.21 is performed according to an exemplary embodiment Fig.19 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0120] Reference Figure 1 and Fig.19 In operation S1210, the panel driver 120 of the display device 100 may receive input image data IDAT, and in operation S1230, the panel driver 120 of the display device 100 may drive the display panel 110 based on the input image data IDAT.

[0121] In operation S1250, the backlight driver 170 may divide the backlight unit 160 into horizontal regions, may perform a vertical direction scanning operation and a horizontal direction sequential driving operation in each horizontal region, and may also perform a frame inversion operation. Fig.17 The operation shown in the display device 100 is different from that performed Fig.19The display device 100 operating as shown in FIG. 1 may group the light source rows of the backlight unit 160 into two light source row groups, and may perform horizontal direction sequential driving operations on the two light source row groups in different horizontal directions in each horizontal region.

[0122] In some exemplary embodiments, Fig. 20 As shown in , the backlight driver 170 may group the light source rows into odd-numbered light source row groups and even-numbered light source row groups. Fig. 20 As shown in FIG. 1310 , in order to perform a horizontal direction sequential driving operation in each of the horizontal regions HR1, HR2, and HR3 in an odd frame, in operation S1270: in an odd frame and in operation S1280, the backlight driver 170 may sequentially drive the light source blocks in the selected light source rows belonging to the odd light source row group in each of the horizontal regions HR1, HR2, and HR3 in a first horizontal direction from the left light source block to the right light source block, and may sequentially drive the light source blocks in the selected light source rows belonging to the even light source row group in each of the horizontal regions HR1, HR2, and HR3 in a second horizontal direction from the right light source block to the left light source block. In addition, as Fig. 20 As shown in FIG. 1330 , in order to perform a horizontal sequential driving operation in each of the horizontal regions HR1, HR2 and HR3 in an even frame, in operation S1270: an even frame and operation S1290, the backlight driver 170 can sequentially drive the light source blocks in the selected light source rows belonging to the odd light source row group in each horizontal region HR1, HR2 and HR3 in the second horizontal direction, and can sequentially drive the light source blocks in the selected light source rows belonging to the even light source row group in each horizontal region HR1, HR2 and HR3 in the first horizontal direction.

[0123] In other exemplary embodiments, Fig.21 As shown in , the backlight driver 170 may group the (4K+1)th light source row and the (4K+2)th light source row among the light source rows into a first light source row group, and may group the (4K+3)th light source row and the (4K+4)th light source row among the light source rows into a second light source row group, where K is an integer greater than 0. Fig.21 As shown in FIG. 1350 , in order to perform a horizontal direction sequential driving operation in each of the horizontal regions HR1, HR2, and HR3 in an odd frame, in operation S12070: in an odd frame and in operation S1280, the backlight driver 170 may sequentially drive the light source blocks in the selected light source row belonging to the first light source row group in each of the horizontal regions HR1, HR2, and HR3 in the first horizontal direction, and may sequentially drive the light source blocks in the selected light source row belonging to the second light source row group in each of the horizontal regions HR1, HR2, and HR3 in the second horizontal direction. In addition, as Fig.21As shown in FIG. 1370 , in order to perform a horizontal sequential driving operation in each of the horizontal regions HR1, HR2 and HR3 in an even frame, in operation S1270: an even frame and operation S1290, the backlight driver 170 can sequentially drive the light source blocks in the selected light source rows belonging to the first light source row group in each horizontal region HR1, HR2 and HR3 in the second horizontal direction, and can sequentially drive the light source blocks in the selected light source rows belonging to the second light source row group in each horizontal region HR1, HR2 and HR3 in the first horizontal direction.

[0124] Fig. 22 is a flowchart of an operation of a display device according to an exemplary embodiment. Fig.23 is performed according to an exemplary embodiment Fig. 22 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0125] Reference Figure 1 and Fig. 22 In operation S1410, the panel driver 120 of the display device 100 may receive input image data IDAT, and in operation S1430, the panel driver 120 of the display device 100 may drive the display panel 110 based on the input image data IDAT.

[0126] In operation S1450, the backlight driver 170 may divide the backlight unit 160 into horizontal regions, may perform a vertical direction scanning operation and a horizontal direction sequential driving operation in each horizontal region, and may also perform a frame inversion operation. Fig.17 The operation shown in the display device 100 is different from that performed Fig. 22 The display device 100 of the operation shown in FIG. 1 may perform horizontal sequential driving operations in different horizontal directions for odd-numbered horizontal areas and even-numbered horizontal areas.

[0127] In some exemplary embodiments, Fig.23 As shown in FIG. 1510 , in order to perform a horizontal sequential driving operation in an odd frame, in operation S1470: in an odd frame and in operation S1480, the backlight driver 170 may sequentially drive the light source blocks in the selected light source rows in the odd horizontal regions HR1 and HR3 in a first horizontal direction from the left light source block to the right light source block, and may sequentially drive the light source blocks in the selected light source rows in the even horizontal region HR2 in a second horizontal direction from the right light source block to the left light source block. In addition, as Fig.23As shown in FIG. 1530 , in order to perform a horizontal sequential driving operation in an even frame, in operation S1470: an even frame and operation S1490, the backlight driver 170 can sequentially drive the light source blocks in the selected light source rows in the odd horizontal regions HR1 and HR3 in the second horizontal direction, and can sequentially drive the light source blocks in the selected light source row in the even horizontal region HR2 in the first horizontal direction.

[0128] Fig.24 is a flowchart of an operation of a display device according to an exemplary embodiment. Fig.25 is performed according to an exemplary embodiment Fig.24 FIG. 1 is a diagram of an operation of a backlight unit of a display device. Fig.26 is performed according to an exemplary embodiment Fig.24 FIG. 1 is a diagram of an operation of a backlight unit of a display device. Fig. 27 is performed according to an exemplary embodiment Fig.24 FIG. 1 is a diagram of an operation of a backlight unit of a display device.

[0129] Reference Figure 1 and Fig.24 In operation S1610, the panel driver 120 of the display device 100 may receive input image data IDAT, and in operation S1630, the panel driver 120 of the display device 100 may drive the display panel 110 based on the input image data IDAT.

[0130] In operation S1650, the backlight driver 170 may divide the backlight unit 160 into horizontal areas, may perform a vertical direction scanning operation and a horizontal direction sequential driving operation in each horizontal area, and may also perform a frame inversion operation, and may also perform a horizontal direction sequential driving operation in different horizontal directions for odd-numbered horizontal areas and even-numbered horizontal areas in operations S1670, S1680, and S1690. Fig.24 The operation of the display device 100 shown in FIG. 1 is performed with Fig. 22 Unlike the display device 100 of the operation shown in FIG. 1 , the horizontal sequential driving operation in the odd horizontal region and the horizontal sequential driving operation in the even horizontal region may have different starting time points and / or different block shift times. Fig. 22 In the display device 100 of the operation shown in FIG. 1 , the light source blocks adjacent to the boundary of the horizontal area can emit light substantially at the same time. Fig.24 In the display device 100 operating as shown in , the light source blocks adjacent to the boundary of the horizontal area may emit light at different time points.

[0131] In an embodiment, if Fig.25As shown in FIG. 1 , the horizontal sequential driving operation in the odd horizontal regions HR1 and HR3 and the horizontal sequential driving operation in the even horizontal region HR2 may have different start time points. Fig.25 As shown in FIGS. 1710 and 1720 of FIG. 17A , the start time point of the horizontal direction sequential driving operation in the even horizontal region HR2 may be delayed compared to the start time point of the horizontal direction sequential driving operation in the odd horizontal regions HR1 and HR3. For example, the vertical direction scanning operation and the horizontal direction sequential driving operation in the odd horizontal regions HR1 and HR3 may be delayed when the vertical start signal STV (see FIG. 17B ) is generated. Figure 1 ), and the vertical direction scanning operation and the horizontal direction sequential driving operation in the even horizontal region HR2 may be started after a predetermined time has passed from the time point when the vertical start signal STV is generated.

[0132] In other exemplary embodiments, Fig.26 As shown in FIG. 1 , the horizontal sequential driving operation in the odd horizontal regions HR1 and HR3 and the horizontal sequential driving operation in the even horizontal region HR2 may have different block shift times. Fig.26 As shown in FIGS. 1730 and 1740 of FIG. 17 , the block shift time of the horizontal direction sequential driving operation in the even horizontal region HR2 may be longer than the block shift time of the horizontal direction sequential driving operation in the odd horizontal regions HR1 and HR3. Therefore, the duration of the horizontal direction sequential driving operation for each light source row in the even horizontal region HR2 may be longer than the duration of the horizontal direction sequential driving operation for each light source row in the odd horizontal regions HR1 and HR3, and in FIGS. 1730 and 1740, the line representing the horizontal direction sequential driving operation for each light source row in the even horizontal region HR2 may have a relatively steep slope.

[0133] In an embodiment, if Fig. 27 As shown in FIG. 1 , the horizontal sequential driving operation in the odd horizontal regions HR1 and HR3 and the horizontal sequential driving operation in the even horizontal region HR2 may have different starting time points and different block shift times. Fig. 27 As shown in FIG. 1750 and FIG. 1760 , the start time point of the horizontal direction sequential driving operation in the even horizontal region HR2 may be delayed compared to the start time point of the horizontal direction sequential driving operation in the odd horizontal regions HR1 and HR3, and the block shift time of the horizontal direction sequential driving operation in the even horizontal region HR2 may be longer than the block shift time of the horizontal direction sequential driving operation in the odd horizontal regions HR1 and HR3. Therefore, the light source blocks adjacent to the boundaries of the horizontal regions HR1, HR2, and HR3 may emit light at different time points.

[0134] Fig.28 is a block diagram of an electronic device 2100 including a display device 2160 according to an exemplary embodiment.

[0135] Reference Fig.28 , the electronic device 2100 may include a processor 2110, a memory device 2120, a storage device 2130, an input / output (I / O) device 2140, a power supply 2150, and a display device 2160. The electronic device 2100 may also include a port for communicating with a video card, a sound card, a memory card, a universal serial bus (USB) device, or other electronic devices.

[0136] The processor 2110 may perform a variety of computing functions or tasks. The processor 2110 may be an application processor (AP), a microprocessor, a central processing unit (CPU), etc. The processor 2110 may be coupled to other components via an address bus, a control bus, a data bus, etc. In addition, in some exemplary embodiments, the processor 2110 may also be coupled to an expansion bus such as a peripheral component interconnect (PCI) bus.

[0137] The memory device 2120 may store data used for the operation of the electronic device 2100. For example, the memory device 2120 may include at least one nonvolatile memory device (such as an erasable programmable read-only memory (EPROM) device, an electrically erasable programmable read-only memory (EEPROM) device, a flash memory device, a phase change random access memory (PRAM) device, a resistive random access memory (RRAM) device, a nano floating gate memory (NFGM) device, a polymer random access memory (PoRAM) device, a magnetic random access memory (MRAM) device, a ferroelectric random access memory (FRAM) device, etc.) and / or at least one volatile memory device (such as a dynamic random access memory (DRAM) device, a static random access memory (SRAM) device, a mobile dynamic random access memory (mobile DRAM) device, etc.).

[0138] The storage device 2130 may be a solid state drive (SSD) device, a hard disk drive (HDD) device, a CD-ROM device, etc. The I / O device 2140 may include an input device (such as a keyboard, a keypad, a mouse, a touch screen, etc.) and / or an output device (such as a printer, a speaker, etc.). The power supply 2150 may provide power for the operation of the electronic device 2100. The display device 2160 may be connected to other components via a bus or other communication link.

[0139] The display device 2160 can perform a vertical scanning operation of sequentially selecting light source rows included in the backlight unit, and a horizontal sequential driving operation of sequentially driving the light source blocks included in the selected light source rows. Therefore, a waterfall phenomenon in which a relatively high brightness or relatively low brightness horizontal line image exists or a relatively high brightness or relatively low brightness horizontal line image gradually moves can be prevented or reduced while performing local dimming.

[0140] The inventive concept may be applied to any display device 2160 and any electronic device 2100 including the display device 2160. For example, the inventive concept may be applied to a television (TV), a digital TV, a 3D TV, a smart phone, a wearable electronic device, a tablet computer, a mobile phone, a personal computer (PC), a home appliance, a laptop computer, a personal digital assistant (PDA), a portable multimedia player (PMP), a digital camera, a music player, a portable game console, a navigation device, and the like.

[0141] The foregoing is an illustration of exemplary embodiments and should not be construed as limiting thereof. Although several exemplary embodiments have been described, it will be readily appreciated by those skilled in the art that many modifications may be made in the exemplary embodiments without substantially departing from the novel teachings and beneficial effects of the inventive concept. Therefore, all such modifications are intended to be included within the scope of the inventive concept as defined in the claims. Therefore, it should be understood that the foregoing is an illustration of various exemplary embodiments and should not be construed as being limited to the specific exemplary embodiments disclosed, and modifications to the disclosed exemplary embodiments and other exemplary embodiments are intended to be included within the scope of the appended claims.

Claims

1. A display device, comprising: A backlight unit comprising light source rows, each of which comprises a light source block; a display panel configured to display an image by transmitting light emitted by the backlight unit; A panel driver configured to drive the display panel; as well as a backlight driver configured to drive the backlight unit, wherein the backlight driver is configured to perform a vertical scanning operation and a horizontal sequential driving operation, wherein the vertical scanning operation sequentially selects the light source rows, and the horizontal sequential driving operation sequentially drives the light source blocks included in the selected light source rows among the light source rows; Wherein, in order to perform the horizontal sequential driving operation, the backlight driver is configured to sequentially drive one of the light source blocks included in the selected light source row among the light source rows based on a second time period; The second period is determined by dividing a delay time from a data input time point to an image display time point by the number of the light source blocks included in each of the light source rows.

2. The display device according to claim 1, wherein: In order to perform the vertical direction scanning operation, the backlight driver is configured to sequentially select one of the light source rows based on a first time period.

3. The display device according to claim 2, wherein: The first time period is determined by dividing a frame time by the number of the light source rows.

4. The display device according to claim 1, wherein: The light source row includes a first light source row and a second light source row, and The backlight driver is configured to start the horizontal sequential driving operation for the second light source row before completing the horizontal sequential driving operation for the first light source row.

5. The display device according to claim 1, wherein: Each of the light source rows includes first to M-th light source blocks, where M is an integer greater than 1, and In which, in order to perform the horizontal sequential driving operation, the backlight driver is configured to sequentially drive the first light source block to the Mth light source block included in the selected light source row in the odd frame in the first horizontal direction from the first light source block to the Mth light source block, and to sequentially drive the first light source block to the Mth light source block included in the selected light source row in the even frame in the second horizontal direction from the Mth light source block to the first light source block.

6. A display device, comprising: A backlight unit comprising light source rows, each of which comprises a light source block; a display panel configured to display an image by transmitting light emitted by the backlight unit; a panel driver configured to drive the display panel; as well as a backlight driver configured to drive the backlight unit, wherein the backlight driver is configured to divide the backlight unit into horizontal areas, and perform a vertical direction scanning operation and a horizontal direction sequential driving operation in each of the horizontal areas, wherein the vertical direction scanning operation sequentially selects the light source rows, and the horizontal direction sequential driving operation sequentially drives the light source blocks included in the selected light source rows among the light source rows; wherein, in order to perform the horizontal direction sequential driving operation in each of the horizontal regions, the backlight driver is configured to sequentially drive one of the light source blocks included in the selected light source rows in each of the horizontal regions with a time shift per block; The block shift time is determined by dividing a delay time from a data input time point to an image display time point by the number of the light source blocks in each of the light source rows included in each of the horizontal areas.

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