Display device and method for display

Abstract

To suppress deterioration in display quality due to generation of black spots, while improving flicker.SOLUTION: A display device (1) includes: a display panel (20); a backlight (30); and a backlight control unit (12) for dividing the backlight (30) into a plurality of regions and controlling light emission luminance of the backlight (30) for each of the plurality of regions on the basis of an image signal (50), the backlight control unit (12) changing light emission luminance of the backlight (30) of a first adjacent illumination region adjacent to the image from luminance indicated by the image signal (50) in a direction in which an image in the image signal moves.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a display device that displays an image illuminated by a backlight. [Background technology]

[0002] A technology known as local dimming for LCD displays divides the backlight into multiple regions and controls the brightness of each of the regions. Local dimming allows for precise adjustment of the backlight to match the brightness of the image, improving the visibility of the display and reducing power consumption. However, there is a problem in that the backlight turning on and off during moving scenes causes flickering, which is easily noticeable to the viewer.

[0003] Therefore, for example, Patent Document 1 describes a liquid crystal display device having a plurality of illumination regions, in which the area or arrangement position of each illumination region is changed at every arbitrary change time. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-175415 Summary of the Invention [Problem to be solved by the invention]

[0005] However, with the above-mentioned conventional technology, the faster the object displayed on the screen moves, the larger the illuminated area becomes. While this reduces flickering, the larger the illuminated area becomes, the harder it is to achieve deep blacks, resulting in a decrease in display quality.

[0006] An object of one embodiment of the present invention is to provide a display device that reduces flickering and suppresses degradation of display quality due to black floating. [Means for solving the problem]

[0007] In order to solve the above problem, a display device according to one embodiment of the present invention comprises a display panel that displays moving images based on an image signal, a backlight that illuminates the display panel, and a backlight control unit that divides the backlight into multiple regions and controls the emission brightness of the backlight for each of the multiple regions based on the image signal, and the backlight control unit changes the emission brightness of the backlight in a first adjacent illumination region adjacent to the image included in the image signal in the direction in which the image moves, from the brightness indicated by the image signal.

[0008] In order to solve the above problems, a display method according to one aspect of the present invention is a display method for a display device having a display panel that displays moving images based on an image signal and a backlight that illuminates the display panel, and includes: a step of inputting an image signal; and a backlight control step of dividing the backlight into a plurality of regions and controlling the emission brightness of the backlight for each of the plurality of regions based on the image signal, wherein in the backlight control step, the emission brightness of the backlight of a first adjacent illumination region adjacent to the image included in the image signal in the direction in which the image moves is changed from the brightness indicated by the image signal. [Effects of the Invention]

[0009] According to one aspect of the present invention, it is possible to suppress degradation of display quality due to black floating while improving flickering. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a functional block diagram showing an overview of a display device according to a first embodiment of the present invention. [Figure 2] FIG. 10 is a diagram showing an example in which a backlight provided in the display device is divided into a plurality of regions. [Figure 3] FIG. 10 is a diagram for explaining an area to be changed based on the luminance indicated by the image signal. [Figure 4] FIG. 10 is a diagram for explaining an area to be changed based on the luminance indicated by the image signal. [Figure 5] FIG. 10 is a diagram for explaining an area to be changed based on the luminance indicated by the image signal. [Figure 6] FIG. 10 is a diagram for explaining an area to be changed based on the luminance indicated by the image signal. [Figure 7] FIG. 10 is a diagram for explaining an area to be changed based on the luminance indicated by the image signal. [Figure 8] FIG. 10 is a diagram for explaining an area to be changed based on the luminance indicated by the image signal. [Figure 9] 10 is a flowchart showing a processing flow in the display device. [Figure 10] FIG. 10 is a functional block diagram showing an overview of a display device according to a second embodiment of the present invention. [Figure 11] FIG. 10 is a functional block diagram showing an overview of a display device according to a third embodiment of the present invention. [Figure 12] 10A and 10B are diagrams for explaining a method for detecting the direction in which a target image moves from a difference in backlight. [Figure 13] 10 is a flowchart showing a processing flow in the display device. DETAILED DESCRIPTION OF THE INVENTION

[0011] [Embodiment 1] An embodiment of the present invention will be described in detail below. In this embodiment, a liquid crystal display device that displays an image illuminated by a backlight will be described as an example of the display device 1. The display device 1 according to this embodiment is capable of implementing a technique called local dimming, which divides the backlight 30 into multiple regions and controls the brightness of each of the multiple regions. Furthermore, the display device 1 is capable of implementing a technique called blurring, which lights up a peripheral region of the illuminated region of the backlight 30.

[0012] 1 is a functional block diagram showing an overview of a display device 1. As shown in FIG.

[0013] The display control unit 10 causes the display panel 20 to display an image based on the input image signal 50. The image display process itself can be performed using known technology, and a detailed description thereof will be omitted here. However, the source driver circuit 21 and the gate driver circuit 22 receive signals from the display control unit 10 and display the image on the display panel 20.

[0014] The display control unit 10 includes a motion vector detection unit 11 (first motion vector detection unit) and a backlight control unit 12. The motion vector detection unit 11 detects a motion vector of an image from an image signal 50. A motion vector is a vector that indicates the deviation between the position of an object in a certain frame of a moving image and the position of a corresponding object in a different frame.

[0015] The backlight control unit 12 controls the backlight 30 using the image signal 50 and the motion vector detected by the motion vector detection unit 11. The backlight control unit 12 also performs the above-mentioned local dimming.

[0016] Note that, when controlling the backlight 30, the backlight control unit 12 may receive data indicating the actual illumination state from the backlight 30 and control the backlight 30 based on the data. In other words, the backlight control unit 12 may receive feedback from the backlight 30 and control the backlight 30.

[0017] FIG. 2 shows an example in which the backlight 30 is divided into multiple regions for performing local dimming. In the example shown in FIG. 2, the backlight 30 is divided into 90 regions, 9 vertically and 10 horizontally. In this specification, the position of each region is indicated using coordinates as follows. The vertical direction of the backlight 30 is the Y direction, the horizontal direction is the X direction, and the vertical direction is Y1 to Y9 from top to bottom and the horizontal direction is X1 to X10 from left to right, and the position of the region is indicated using XY coordinates. For example, the upper left region of the backlight 30 is (X1, Y1), and from this region to the right, the regions are (X2, Y1), (X3, Y1), (X4, Y1), .... Similarly, from the upper left to bottom, the regions are (X1, Y1), (X1, Y2), (X1, Y3), .... Local dimming allows the brightness of each of these multiple regions to be controlled. Details of the processing by the backlight control unit 12 will be described later.

[0018] [Details of Processing by Backlight Control Unit 12] Next, details of the processing by the backlight control unit 12 will be described with reference to Figures 3 to 8. As described above, the backlight control unit 12 controls the backlight 30 using the image signal 50 and the motion vector detected by the motion vector detection unit 11.

[0019] More specifically, for a moving image, when the area of ​​the backlight 30 corresponding to the moving image is defined as the corresponding illumination area, the backlight control unit 12 changes the emission luminance of an adjacent illumination area (first adjacent illumination area), which is an area adjacent to the corresponding illumination area in the direction of the motion vector of the image, from the emission luminance indicated by the image signal 50. For example, the emission luminance of the adjacent illumination area is changed to a luminance higher than the emission luminance indicated by the image signal 50. If the luminance of the adjacent illumination area is set to the luminance indicated by the image signal 50, the difference with the corresponding illumination area may become too large, which may cause flickering as the image moves. As described above, by increasing the luminance of the adjacent illumination area higher than the emission luminance indicated by the image signal 50, the difference with the corresponding illumination area is reduced, thereby suppressing flickering.

[0020] The backlight control unit 12 may illuminate the adjacent illumination area with a light emission luminance higher than the light emission luminance indicated by the image signal 50 and lower than the light emission luminance of the corresponding illumination area. This makes it possible to suppress black floating while preventing flickering caused by the movement of the image TP for which a motion vector has been detected, thereby achieving a balanced suppression of flickering and black floating.

[0021] A specific example will be described below. 301 in Fig. 3 indicates the backlight 30 and the image TP displayed on the display panel 20. An area AR1 of the backlight 30 that corresponds to the image TP is the corresponding illumination area. In terms of the position coordinates described above, the area AR1, with its upper left being (X3, Y6) and its lower right being (X5, Y8), is the corresponding illumination area. In addition, areas AR1A ((X6, Y6), (X6, Y7), (X6, Y8)) and area AR1B ((X2, Y6), (X2, Y7), (X2, Y8)) that are adjacent to the area AR1 in the motion vector direction of the image TP (here, the X direction) are the adjacent illumination areas.

[0022] 302 in Fig. 3 shows an image of illumination by the backlight 30 when displaying the image TP shown in 301. As shown in 302 in Fig. 3, when displaying the image TP, an area AR1 corresponding to the illumination area is illuminated, and areas AR1A and AR1B, which are adjacent illumination areas adjacent to the illumination area in the motion vector direction, are illuminated. Note that this shows a state in which the luminance of areas AR1A and AR1B is lower than the luminance of area AR1.

[0023] The backlight control unit 12 may vary the light emission luminance of adjacent illumination areas depending on the magnitude of the motion vector. For example, the backlight control unit 12 may increase the light emission luminance as the motion vector increases.

[0024] Fig. 4 shows an example illustrating the difference between the magnitude of the motion vector and the emission luminance of the adjacent illumination area. Fig. 4 shows an example in which the motion vector of image TP shown in 402 is larger than that of image TP shown in 401. As shown in Fig. 4, the emission luminance of the adjacent illumination area (areas AR1A and AR1B) in 401 is smaller than that of the adjacent illumination area (areas AR1A and AR1B) in 402. Since the magnitude of the motion vector indicates the speed of movement of image TP, by changing the emission luminance of the adjacent illumination area according to the magnitude of the motion vector, it is possible to achieve an emission luminance that corresponds to the speed of movement of image TP, and to suppress flickering and floating blacks that accompany the movement of image TP in a balanced manner.

[0025] When the magnitude of the motion vector exceeds a threshold, the backlight control unit 12 may change the emission brightness of adjacent illumination areas adjacent to the corresponding illumination area in a direction different from the direction of the motion vector, in addition to the adjacent illumination areas adjacent to the direction of the motion vector.

[0026] 5 shows areas of the backlight 30 whose light emission brightness is changed when the magnitude of the motion vector exceeds a threshold. Reference numeral 501 in FIG. 5 indicates the backlight 30 and an image displayed on the display panel 20, and reference numeral 502 indicates an image illuminated by the backlight 30 when the image shown in 501 is displayed. As shown in 501 in FIG. 5, when the magnitude of the motion vector exceeds a threshold, the backlight control unit 12 may change the light emission brightness of areas AR1A ((X6, Y6), (X6, Y7), (X6, Y8)) and AR1B ((X2, Y6), (X2, Y7), (X2, Y8)) adjacent to area AR1, as well as areas AR1C ((X3, Y5), (X4, Y5), (X5, Y5)) and AR1D ((X3, Y9), (X4, Y9), (X5, Y9)).

[0027] In addition, as shown in Figure 6, the backlight control unit 12 may change the emission brightness of areas AR1A, AR1B, AR1C, and AR1D, as well as areas (X2, Y5), (X6, Y5), (X2, Y9), and (X6, Y9) where the four corners of area AR1 meet.

[0028] Of the adjacent illumination areas adjacent to an illumination area, the adjacent illumination area adjacent in the direction of the motion vector is called the first adjacent illumination area, and the adjacent illumination area adjacent in a direction different from the motion vector direction is called the second adjacent illumination area. In this case, areas AR1A and AR1B are the first adjacent illumination areas, and areas AR1C and AR1D are the second adjacent illumination areas.

[0029] When the magnitude of the motion vector exceeds a threshold, the illumination brightness of the second adjacent illumination area is changed in addition to the first adjacent illumination area. If the speed of movement of the image TP is faster than the threshold, the illumination area whose illumination brightness is changed is enlarged, thereby further suppressing flickering associated with image movement.

[0030] The backlight control unit 12 may also change the emission brightness of the region adjacent to the adjacent illumination region in the direction of the motion vector according to the magnitude of the motion vector. Furthermore, the backlight control unit 12 may increase the region in the direction of the motion vector for which the emission brightness is changed as the magnitude of the motion vector increases. In other words, the backlight control unit 12 may also change the emission brightness of the third adjacent illumination region adjacent to the first adjacent illumination region in the direction of the motion vector according to the magnitude of the motion vector.

[0031] FIG. 7 shows an example of an area of ​​the backlight 30 whose light emission luminance is changed according to the magnitude of the motion vector. Reference numeral 701 in FIG. 7 denotes the backlight 30 and an image displayed on the display panel 20, and reference numeral 702 denotes an image illuminated by the backlight 30 when the image shown in 701 is displayed. In the example described above, the light emission luminance of areas AR1A and AR1B adjacent to the area AR1, which is an illumination area, in the direction of the motion vector was changed. In this example, as the motion vector increases, the backlight control unit 12 also changes the light emission luminance of areas AR1E ((X7, Y6), (X7, Y7), (X7, Y8)) and AR1F ((X1, Y6), (X1, Y7), (X1, Y8)), which are adjacent to areas AR1A and AR1B in the direction of the motion vector. In this example, areas AR1A and AR1B are the first adjacent illumination area, and areas AR1E and AR1F are the third adjacent illumination area.

[0032] Furthermore, when the magnitude of the motion vector increases, the backlight control unit 12 may change the light emission brightness of the areas ((X8, Y6), (X8, Y7), (X8, Y8)) adjacent to area AR1E in the motion vector direction. In other words, the backlight control unit 12 may increase the number of third adjacent illumination areas whose light emission brightness is changed in the motion vector direction.

[0033] This makes it possible to increase the number of illumination areas in the direction of movement of the image TP, the illumination areas having their light emission luminance changed depending on the speed of movement of the image TP, thereby further suppressing flickering that accompanies movement of the image TP.

[0034] The backlight control unit 12 may determine the emission luminance of the adjacent illumination region according to the difference in luminance between the image TP, for which a motion vector based on the image signal 50 has been detected, and the background. For example, when displaying an image such as that shown in FIG. 8, the luminance of the adjacent illumination region may be increased as the difference between the luminance of the image TP and the luminance of the background, for example, the luminance of the region BK, increases. This allows the emission luminance of the adjacent illumination region to be determined according to the difference in luminance between the image TP, for which a motion vector has been detected, and the background, and therefore the emission luminance of the adjacent illumination region can be determined taking the background into consideration. This allows for well-balanced illumination of the image TP and the background, reducing the sense of discomfort felt by the viewer regarding the overall image.

[0035] The backlight control unit 12 may determine the emission luminance of the adjacent illumination region in accordance with the signal level of the entire screen based on the image signal 50. For example, the backlight control unit 12 may increase the emission luminance of the adjacent illumination region as the signal level of the entire screen based on the image signal 50 increases. Here, the signal level refers to the gradation indicated by the image signal 50, and the signal level of the entire screen refers to the average value of the gradation of the entire screen, i.e., all pixels included in one frame. By determining the luminance of the adjacent illumination region in accordance with the signal level of the entire screen, it is possible to achieve an emission luminance that takes into account the smoothness of the entire screen. This reduces the sense of discomfort felt by the viewer when viewing an image.

[0036] The backlight control unit 12 may determine the emission luminance of the adjacent illumination region according to the luminance level of the entire screen based on the image signal 50. For example, the backlight control unit 12 may increase the emission luminance of the adjacent illumination region as the luminance level of the entire screen based on the image signal 50 increases. Here, the luminance level is the average value of the luminance of the entire screen. By using the average value of the luminance of the entire screen as the luminance level, the emission luminance of the adjacent illumination region can be made closer to the actual state. For example, in the case of an image in which a white window is displayed on a black background, if the window size is small, the median value will be black. Therefore, the emission luminance is determined to correspond to a dark image. On the other hand, the average value is slightly brighter, and the emission luminance is also determined to correspond to a bright image. Therefore, by using the average value, the emission luminance can be made closer to the actual state. Note that the median value of the luminance of the entire screen may be used as the luminance level.

[0037] By determining the emission luminance of the adjacent illumination area according to the luminance level of the entire screen, it is possible to achieve an emission luminance that takes into account the brightness of the entire screen, thereby reducing the sense of incongruity felt by viewers when viewing an image.

[0038] [Processing flow in the display device 1] Next, the flow of processing in the display device 1 will be described with reference to FIG. 9. FIG. 9 is a flowchart showing the flow of processing in the display device 1. As shown in FIG. 9, when an image signal 50 is input to the display device 1 (S101), the motion vector detection unit 11 detects a motion vector of the image included in the image signal 50 (S102, motion vector detection step). Then, when the display control unit 10 displays the image represented by the image signal 50 on the display panel 20, the display control unit 10 displays the image represented by the image signal 50 by lighting the backlight 30 as follows. That is, the backlight control unit 12 changes the emission brightness of an adjacent illumination area that is adjacent in the motion vector direction to the illumination area corresponding to the image of the motion vector detected by the motion vector detection unit 11 from the emission brightness indicated by the image signal 50, and turns on the backlight 30 (S103, backlight control step). As a result, the image is displayed with the adjacent illumination area illuminated. This completes the flow of processing in the display device 1.

[0039] [Embodiment 2] Other embodiments of the present invention will be described below. For ease of explanation, the same reference numerals will be used to designate components having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

[0040] 10 is a functional block diagram showing the configuration of a main part of a display device 1A according to this embodiment. As shown in FIG. 10, the display device 1A according to this embodiment differs from the display device 1 described above in that it includes an illuminance sensor 40.

[0041] The illuminance sensor 40 measures the illuminance in the environment in which the display device 1 is placed and notifies the display control unit 10 of the measurement result. The backlight control unit 12 of the display control unit 10 determines the emission luminance of the adjacent illumination region using the measurement result by the illuminance sensor 40. For example, the backlight control unit 12 may increase the emission luminance of the adjacent illumination region as the illuminance measured by the illuminance sensor 40 increases.

[0042] This allows the emission luminance of the adjacent illumination region to be determined according to the brightness of the environment surrounding the display device 1, so that the emission luminance can be determined taking into account the brightness of the environment surrounding the display device 1.

[0043] [Modification] Although the configuration using the illuminance sensor 40 has been described above, the present invention is not limited to this, and the display device 1 may also be configured to include a temperature sensor, a watt-hour meter, and the like.

[0044] For example, if a temperature sensor is provided, the backlight control unit 12 may determine the emission luminance of the adjacent illumination area in accordance with the temperature of the display device 1 measured by the temperature sensor, thereby preventing the temperature of the display device 1 from becoming too high.

[0045] Furthermore, if a watthour meter is provided, the backlight control unit 12 may determine the emission luminance of the adjacent illumination area in accordance with the power consumption of the display device 1 measured by the watthour meter, thereby preventing the power consumption of the display device 1 from becoming too high.

[0046] [Embodiment 3] Other embodiments of the present invention will be described below. For ease of explanation, the same reference numerals will be used to designate components having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

[0047] 11 is a functional block diagram showing the configuration of a main part of a display device 1B according to this embodiment. As shown in FIG. 11, the display device 1B according to this embodiment differs from the above-described display devices 1 and 1A in that a backlight control unit 12A includes a motion vector detection unit 121 (second motion vector detection unit).

[0048] The motion vector detection unit 121 detects a motion vector indicating the movement of the target image, which is an image with movement, based on the light emission luminance of the backlight 30 controlled by the backlight control unit 12A. More specifically, this is as follows.

[0049] 12 is a diagram illustrating a method for detecting, as a motion vector, the direction in which a target image TP1, which is an image included in the image signal 50, moves, from the difference in the emission luminance of the backlight 30. Reference numeral 1201 in FIG. 12 shows an example in which the target image TP1 is displayed in a certain frame. Reference numeral 1202 shows an example of the emission state of the backlight 30 in this frame. As shown in reference numeral 1202, when the target image TP1 is displayed as shown in reference numeral 1201, the backlight control unit 12A turns on the backlight 30 so as to increase the luminance in an area AR10, which is an area corresponding to the target image TP1.

[0050] Reference numeral 1203 in FIG. 12 indicates a frame following 1201. Here, target image TP2 is displayed. Target image TP2 is the same image as target image TP1, but its display position has moved from the frame indicated by 1201. Reference numeral 1204 indicates an example of the light emission state of backlight 30 in this frame. As indicated by 1204, when target image TP2 is displayed as indicated by 1203, backlight control unit 12A turns on backlight 30 so as to increase the luminance in area AR11, which is the area corresponding to target image TP2.

[0051] In this way, the light emission state of the backlight 30 differs between frames. The motion vector detection unit 121 detects the direction in which the target image moves from the difference in light emission luminance of the backlight 30 between these frames. Here, a motion vector MV1 is detected from the change in position between areas AR10 and AR11, which are areas with high light emission luminance.

[0052] As described above, the motion vector detection unit 121 of the backlight control unit 12A detects the direction in which the target image moves using the difference between the emission luminance corresponding to a certain frame in a moving image and the emission luminance corresponding to the frame following the certain frame. This can also be said to detect the difference in the emission luminance of the backlight 30 as a motion vector. As a result, the direction in which the target image moves can be detected from the difference in the emission luminance of the backlight, and therefore the direction in which the target image moves can be detected from only the backlight data. Therefore, the detection of the direction in which the target image moves can be processed as part of backlight control. In other words, the detection of the motion vector can be processed as part of backlight control.

[0053] In detecting the difference in backlight 30 between frames, the frame to be compared with a certain frame does not necessarily have to be the next frame in time. For example, the difference between a certain frame and a frame after a predetermined time has elapsed may be used, or the difference between a certain frame and a frame after skipping a predetermined number of frames may be used.

[0054] [Processing flow in display device 1B] Next, the flow of processing in the display device 1B will be described with reference to FIG. 13. FIG. 13 is a flowchart showing the flow of processing in the display device 1B. As shown in FIG. 13, when an image signal 50 is input to the display device 1B (S201), the display control unit 10 displays an image represented by the image signal 50 on the display panel 20 by lighting the backlight 30 as follows. That is, the backlight control unit 12A changes the light emission brightness of an adjacent lighting area that is adjacent in the motion vector direction to an lighting area corresponding to an image of a motion vector detected by the motion vector detection unit 121 from the light emission brightness indicated by the image signal 50, and turns on the backlight 30 (S202, backlight control step). As a result, an image is displayed with the adjacent lighting area illuminated. This completes the flow of processing in the display device 1B.

[0055] As described above, the display devices 1, 1A, and 1B according to the present disclosure include a display panel 20 that displays a moving image based on an image signal 50, a backlight 30 that illuminates the display panel 20, and a backlight control unit 12 or 12A. The backlight control unit 12 or 12A divides the backlight 30 into multiple regions and controls the emission brightness of the backlight 30 for each of the multiple regions based on the image signal 50. The backlight control unit 12 or 12A then changes the emission brightness of the backlight 30 for a corresponding illumination region corresponding to a target image in the moving image and a first adjacent illumination region adjacent to the target image in the direction of movement from the brightness indicated by the image signal 50. In other words, the backlight control unit 12 or 12A changes the emission brightness of the backlight 30 for a first adjacent illumination region adjacent to the image (target image) included in the image signal 50 in the direction of movement of the image from the brightness indicated by the image signal 50.

[0056] This changes the light emission brightness of the corresponding illumination area and the first adjacent illumination area that is adjacent in the direction in which the target image moves. Therefore, since the entire corresponding illumination area does not need to be enlarged as in conventional technology, it is possible to narrow the area in which black floating may occur in the image. This makes it possible to reduce flicker while suppressing degradation of display quality due to black floating.

[0057] The target image is not limited to that included in the image signal, but may be a character, avatar, or the like generated by the display device 1 itself. The target image may also be a character, avatar, or the like generated by a server or the like different from the source of the image signal. The character, avatar, or the like may be generated by the same server or the like as the source of the image signal. An avatar is a character registered in a virtual space. Images of these characters, avatars, or the like are displayed in combination with moving images (content images) represented by the image signal 50. The content image and the image of the character, avatar, or the like may be displayed overlapping each other or in different areas.

[0058] [Software implementation example] The functions of the display device 1 (hereinafter referred to as the "device") can be realized by a program that causes a computer to function as the device, and a program that causes a computer to function as each control block of the device (particularly each part included in the display control unit 10).

[0059] In this case, the device includes a computer having at least one control device (e.g., a processor) and at least one storage device (e.g., a memory) as hardware for executing the program. The control device and storage device execute the program, thereby realizing the functions described in each of the above embodiments.

[0060] The program may be non-transitory and may be recorded on one or more computer-readable recording media. The recording media may or may not be included in the device. In the latter case, the program may be supplied to the device via any wired or wireless transmission medium.

[0061] Furthermore, some or all of the functions of the control blocks can be realized by logic circuits. For example, an integrated circuit in which a logic circuit that functions as each of the control blocks is formed is also included in the scope of the present invention. In addition, the functions of the control blocks can also be realized by, for example, a quantum computer.

[0062] Furthermore, each process described in each of the above embodiments may be executed by AI (Artificial Intelligence). In this case, the AI ​​may run on the control device or on another device (for example, an edge computer or a cloud server).

[0063] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. Furthermore, new technical features can be formed by combining the technical means disclosed in each embodiment.

[0064] 〔summary〕 A display device according to a first aspect of the present invention includes a display panel that displays moving images based on an image signal, a backlight that illuminates the display panel, and a backlight control unit that divides the backlight into multiple regions and controls the backlight's emission luminance for each of the multiple regions based on the image signal. The backlight control unit changes the emission luminance of the backlight in a first adjacent illumination region adjacent to an image in the direction in which the image included in the image signal moves, from the luminance indicated by the image signal. According to this configuration, the emission luminance of the first adjacent illumination region adjacent to the image in the direction in which the image moves is changed. Therefore, unlike conventional techniques, the entire illumination region corresponding to the image is not enlarged, thereby narrowing the area in which black floating may occur in the image. This reduces flicker while suppressing degradation of display quality due to black floating.

[0065] According to a second aspect of the present invention, in the display device of the first aspect, the display device further includes a first motion vector detection unit that detects a motion vector of the image included in the image signal, and the backlight control unit determines, as the first adjacent illumination area, the area adjacent to the corresponding illumination area corresponding to the image in the direction indicated by the detected motion vector. According to the above configuration, the area adjacent to the corresponding illumination area in the direction indicated by the detected motion vector can be determined as the first adjacent illumination area.

[0066] A display device according to a third aspect of the present invention is the same as that of the first aspect, wherein the backlight control unit detects the direction in which the target image moves by using a difference between the emission luminance corresponding to a certain frame in the moving image and the emission luminance corresponding to a frame subsequent to the certain frame. According to the above configuration, the direction in which the target image moves can be detected from the difference in the emission luminance of the backlight, and therefore the direction in which the target image moves can be detected from backlight data alone. This allows the detection of the direction in which the target image moves to be processed as part of backlight control.

[0067] The display device according to Aspect 4 of the present invention is the display device according to Aspect 3, further comprising a second motion vector detection unit that detects the direction in which the target image moves as a motion vector. With this configuration, the direction in which the target image moves can be detected using the motion vector.

[0068] In a display device according to aspect 5 of the present invention, in accordance with aspect 2 or 4, the backlight control unit lights the first adjacent illumination region with a lower emission luminance than the corresponding illumination region. With this configuration, the emission luminance of the first adjacent illumination region is lower than that of the target illumination region, thereby making it possible to suppress flickering and floating blacks that accompany movement of an image for which a motion vector has been detected in a balanced manner.

[0069] A display device according to a sixth aspect of the present invention is similar to the fifth aspect in that the backlight control unit varies the emission luminance of the first adjacent illumination region depending on the magnitude of the motion vector. This configuration allows the emission luminance to be adjusted according to the speed of image movement for which the motion vector is detected, thereby enabling well-balanced suppression of flicker and floating blacks associated with image movement.

[0070] In a display device according to a seventh aspect of the present invention, in the fifth or sixth aspect, when the magnitude of the motion vector exceeds a threshold, the backlight control unit changes the emission brightness of not only the first adjacent illumination area but also a second adjacent illumination area that is adjacent to the corresponding illumination area in a direction different from the direction of the motion vector. According to the above configuration, when the speed of image movement for which the motion vector is detected is faster than a threshold, the illumination area whose emission brightness is changed is enlarged, thereby making it possible to further suppress flickering caused by image movement.

[0071] In a display device according to an eighth aspect of the present invention, in any one of the fifth to seventh aspects, the backlight control unit also changes the emission luminance of a third adjacent illumination region adjacent to the first adjacent illumination region in the direction of the motion vector according to the magnitude of the motion vector. This configuration makes it possible to increase the number of illumination regions whose emission luminance is changed in the direction of image movement according to the speed of image movement for which the motion vector is detected, thereby further suppressing flickering caused by image movement.

[0072] A display device according to a ninth aspect of the present invention is any of the fifth to eighth aspects, wherein the backlight control unit increases the number of the third adjacent illumination regions, the number of which changes light emission luminance, in the direction of the motion vector as the magnitude of the motion vector increases. With this configuration, the number of illumination regions, the number of which changes light emission luminance, can be increased in the direction of the image movement according to the speed of the image movement for which the motion vector is detected, thereby further suppressing flickering caused by image movement.

[0073] A display device according to aspect 10 of the present invention is any of aspects 5 to 9, wherein the backlight control unit determines the emission luminance of the first adjacent illumination region in accordance with a difference in luminance between the image in which the motion vector based on the image signal is detected and the background. According to the above configuration, the emission luminance of the first adjacent illumination region is determined in accordance with a difference in luminance between the image in which the motion vector is detected and the background, thereby enabling the emission luminance to take the background into consideration. This reduces the sense of incongruity felt by the viewer when viewing the image.

[0074] A display device according to aspect 11 of the present invention is any of aspects 1 to 10, wherein the backlight control unit determines the emission luminance of the first adjacent illumination region in accordance with the signal level of the entire screen based on the image signal. According to the above configuration, the emission luminance of the first adjacent illumination region is determined in accordance with the signal level of the entire image, thereby enabling the emission luminance to be determined in consideration of the smoothness of the entire image. This reduces the sense of discomfort felt by the viewer when viewing the image. Here, the signal level refers to the average value of the gradation of the entire image.

[0075] A display device according to aspect 12 of the present invention is any of aspects 1 to 11, wherein the backlight control unit determines the emission luminance of the first adjacent illumination region in accordance with the luminance level of the entire screen based on the image signal. According to this configuration, the emission luminance of the first adjacent illumination region is determined in accordance with the luminance level of the entire image, thereby enabling the emission luminance to be determined taking into account the brightness of the entire image. This reduces the sense of discomfort felt by the viewer when viewing the image. Here, the luminance level refers to the average or median luminance of the entire image.

[0076] A display device according to Aspect 13 of the present invention is any of Aspects 1 to 12, further comprising an illuminance sensor, and the backlight control unit determines the emission luminance of the first adjacent illumination region in accordance with a measurement result of the illuminance sensor. With this configuration, the emission luminance of the first adjacent illumination region is determined in accordance with the brightness of the environment surrounding the display device, so that the emission luminance can be determined taking into account the brightness of the environment surrounding the display device.

[0077] A display method according to aspect 14 of the present invention is a display method for a display device having a display panel that displays moving images based on an image signal and a backlight that illuminates the display panel, and includes a step of inputting an image signal, and a backlight control step of dividing the backlight into multiple areas and controlling the emission brightness of the backlight for each of the multiple areas based on the image signal, wherein in the backlight control step, the emission brightness of the backlight of a first adjacent illumination area adjacent to the image included in the image signal in the direction in which the image moves is changed from the brightness indicated by the image signal.

[0078] The display device according to each aspect of the present invention may be realized by a computer, in which case the control program for the display device that causes the computer to operate as each part (software element) of the display device to realize the display device on the computer, and the computer-readable recording medium on which the program is recorded, also fall within the scope of the present invention. [Explanation of symbols]

[0079] 1, 1A, 1B display device 10 Display control unit 11 Motion vector detection unit (first motion vector detection unit) 12, 12A Backlight control unit 121 motion vector detection unit (second motion vector detection unit) 20 Display panel 21 Source driver circuit 22 Gate driver circuit 30 Backlight 40 Illuminance sensor 50 Image Signal

Claims

1. a display panel that displays a moving image based on an image signal; a backlight for illuminating the display panel; a backlight control unit that divides the backlight into a plurality of regions and controls the light emission luminance of the backlight for each of the plurality of regions based on the image signal; The backlight control unit changes the emission brightness of the backlight in a first adjacent illumination region adjacent to the image included in the image signal in a direction in which the image moves, from the brightness indicated by the image signal.

2. a first motion vector detection unit that detects a motion vector of the image included in the image signal; The display device according to claim 1 , wherein the backlight control unit determines the area adjacent to the corresponding illumination area corresponding to the image in a direction indicated by the detected motion vector as the first adjacent illumination area.

3. The display device according to claim 1 , wherein the backlight control unit detects the direction in which the image moves by using a difference between the emission luminance corresponding to a certain frame in the moving image and the emission luminance corresponding to a frame subsequent to the certain frame.

4. The display device according to claim 3 , further comprising a second motion vector detector that detects a difference in the emission luminance of the backlight as a motion vector.

5. The display device according to claim 2 , wherein the backlight control unit lights the first adjacent illumination region with a lower emission luminance than the corresponding illumination region.

6. The display device according to claim 2 , wherein the backlight control unit varies the light emission luminance of the first adjacent illumination region depending on the magnitude of the motion vector.

7. 3. The display device according to claim 2, wherein, when the magnitude of the motion vector exceeds a threshold, the backlight control unit changes the emission brightness of not only the first adjacent illumination area but also a second adjacent illumination area that is adjacent to the corresponding illumination area in a direction different from the direction of the motion vector.

8. The display device according to claim 2 , wherein the backlight control unit also changes the emission luminance of a third adjacent illumination region that is adjacent to the first adjacent illumination region in the direction of the motion vector, in accordance with the magnitude of the motion vector.

9. The display device according to claim 8 , wherein the backlight control unit increases the number of the third adjacent illumination regions, the light emission luminance of which is changed, in the direction of the motion vector as the magnitude of the motion vector increases.

10. The display device according to claim 2 , wherein the backlight control unit determines the emission luminance of the first adjacent illumination region according to a luminance difference between the image in which the motion vector based on the image signal is detected and a background.

11. The display device according to claim 1 , wherein the backlight control unit determines the light emission luminance of the first adjacent illumination region in accordance with a signal level of the entire screen based on the image signal.

12. The display device according to claim 1 , wherein the backlight control unit determines the light emission luminance of the first adjacent illumination region in accordance with a luminance level of the entire screen based on the image signal.

13. Equipped with an illuminance sensor, The display device according to claim 1 , wherein the backlight control unit determines the light emission luminance of the first adjacent illumination region in accordance with a measurement result of the illuminance sensor.

14. A display method for a display device including a display panel that displays a moving image based on an image signal and a backlight that illuminates the display panel, comprising: An image signal is input; a backlight control step of dividing the backlight into a plurality of regions and controlling the light emission luminance of the backlight for each of the plurality of regions based on the image signal; In the backlight control step, the emission brightness of the backlight of a first adjacent illumination region adjacent to the image included in the image signal in a direction in which the image moves is changed from the brightness indicated by the image signal.

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