Display device and control method of the same

Abstract

To provide a display deice which can prevent overcurrent from flowing in a power supply circuit guiding current to a backlight.SOLUTION: A display device includes a backlight including a plurality of light-emitting regions sectioned into a plurality of division areas, and a control device for controlling the backlight on the basis of backlight data acquired from video data having a plurality of frames, wherein in an update period during which the backlight data is updated from a current frame to a next frame of the plurality of frames for each of the plurality of division areas, when the backlight data of the current frame and the backlight data of the next frame are mixed, if a current value relating to the backlight is larger than a predetermined value, the control device corrects the backlight data of the next frame in the update period so as to lower the current value, and controls the backlight on the basis of the backlight data of the corrected next frame.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a display device and a control method thereof. [Background technology]

[0002] In recent years, display devices such as that disclosed in Patent Document 1 have been developed. Such display devices include a backlight, a display panel, and a control device. In the backlight, a plurality of light-emitting regions are arranged in a matrix. The display panel displays moving images using light emitted from the plurality of light-emitting regions. The control device controls the backlight and the display panel based on an input video signal received from the outside. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-220200 A Summary of the Invention [Problem to be solved by the invention]

[0004] According to the technology disclosed in the above Patent Document 1, the control device calculates the total value of the current flowing through all of the multiple light-emitting areas for each frame of the image, and adjusts the gradation (light emission amount) of the multiple light-emitting elements so that the total value of the current does not exceed an upper limit value. This display device uses Mini-LEDs (Light Emitting Diodes), and therefore has a large number of multiple light-emitting areas that make up the backlight. Therefore, the value of the current flowing through the backlight corresponding to one frame fluctuates greatly. Therefore, when switching between one frame of a specific pattern, an overcurrent may flow through the power supply circuit that directs current to the backlight.

[0005] However, in the technology disclosed in the above-mentioned Patent Document 1, the value of the current flowing through the power supply circuit that guides the current to the backlight is calculated for each frame. Therefore, the above-mentioned overcurrent cannot be detected until the backlight data for the entire frame is read. Therefore, it is not possible to prevent the above-mentioned overcurrent from flowing when switching frames of a specific pattern.

[0006] The present disclosure has been made in consideration of the above-mentioned problems. An object of the present disclosure is to provide a display device and a control method thereof that can suppress an overcurrent from flowing in a power supply circuit that guides a current to a backlight. [Means for solving the problem]

[0007] The display device of the present disclosure includes a backlight including a plurality of light-emitting regions divided into a plurality of divided areas, and a control device that controls the backlight based on backlight data obtained from video data having a plurality of frames, wherein during an update period in which the backlight data is updated from a current frame to a next frame among the plurality of frames for each of the plurality of divided areas, when the backlight data of the current frame and the backlight data of the next frame are mixed, if a current value associated with the backlight is greater than a predetermined value, the control device corrects the backlight data of the next frame during the update period so as to lower the current value, and controls the backlight based on the corrected backlight data of the next frame.

[0008] The control method for a display device disclosed herein is a control method for a display device including a backlight including a plurality of light-emitting regions divided into a plurality of divided areas, and a control device that controls the backlight based on backlight data obtained from video data having a plurality of frames, wherein during an update period in which the backlight data is updated from a current frame to a next frame among the plurality of frames for each of the plurality of divided areas, when the backlight data of the current frame and the backlight data of the next frame are mixed, if a current value related to the backlight is greater than a predetermined value, the control device executes the steps of: correcting the backlight data of the next frame during the update period so as to lower the current value; and controlling the backlight based on the corrected backlight data of the next frame. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a functional block diagram of a display device according to an embodiment. [Diagram 2] 10A to 10C are diagrams illustrating a backlight data correction process executed by a control device of the display device according to the embodiment. [Diagram 3] FIG. 1 is a first diagram for explaining a process for detecting an overcurrent executed by a control device of a display device according to an embodiment. [Figure 4] FIG. 2 is a second diagram for explaining the process for detecting an overcurrent executed by the control device of the display device according to the embodiment. [Diagram 5] FIG. 3 is a third diagram for explaining the process for detecting an overcurrent executed by the control device of the display device according to the embodiment. [Figure 6] FIG. 4 is a fourth diagram for explaining a process for detecting an overcurrent executed by the control device of the display device according to the embodiment; [Figure 7] 10A and 10B are diagrams for explaining a manner in which overcurrent detection is suppressed by a process executed by a control device of the display device according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, a display device according to an embodiment of the present disclosure will be described with reference to the drawings. In the drawings, the same or equivalent elements are designated by the same reference numerals, and redundant description will not be repeated.

[0011] A display device 1000 according to an embodiment will be described with reference to FIGS.

[0012] FIG. 1 is a functional block diagram of a display device 1000 according to an embodiment.

[0013] As shown in FIG. 1, the display device 1000 includes a display panel DP, a backlight BL, a power supply circuit PW, and a control device 100.

[0014] The display panel DP is, for example, a liquid crystal display panel. The liquid crystal display panel has a plurality of pixels PX arranged in a matrix. Each of the plurality of pixels PX includes a set of sub-pixels, for example, a red sub-pixel, a green sub-pixel, and a blue sub-pixel. The red sub-pixel has a red filter that mainly transmits red light. The green sub-pixel has a green filter that mainly transmits green light. The blue sub-pixel has a blue filter that mainly transmits blue light.

[0015] The backlight BL is disposed to face the display panel DP. The backlight BL has a plurality of light-emitting regions ER. The light-emitting regions ER are arranged in a matrix. In each of the light-emitting regions ER, a plurality of light-emitting elements, such as a plurality of MinLEDs (Light Emitting Diodes), are arranged in a matrix. The resolution of the light-emitting regions ER arranged in a matrix on the backlight BL is lower than the resolution of the pixels PX arranged in a matrix on the display panel DP.

[0016] The power supply circuit PW receives power from an external source and supplies power to each of the display panel DP, the backlight BL, and the control device 100. In this embodiment, the power supply circuit PW changes the magnitude of the current supplied to each of the display panel DP, the backlight BL, and the control device 100. In this embodiment, the power supply circuit PW passes a current through each of the multiple light-emitting regions ER of the backlight BL.

[0017] The control device 100 controls the luminance (or lighting rate) of the backlight BL by controlling the current flowing from the power supply circuit PW to each of the light emitting regions ER. Therefore, the power supply circuit PW is required to generate a current corresponding to the total value of the currents actually flowing through the light emitting regions ER.

[0018] However, even if the power supply circuit PW tries to make all of the light-emitting areas ER emit light at maximum brightness (maximum lighting rate = 100%), it cannot supply the current required by all of the light-emitting areas ER. In other words, the maximum value of the current that the power supply circuit PW can actually supply is smaller than the total value of the current required to make all of the light-emitting areas ER emit light at maximum brightness. Therefore, the control device 100 needs to limit the total value of the current supplied to the light-emitting areas ER, which will be described in detail later.

[0019] The control device 100 controls the voltage applied to the liquid crystal layer constituting each of a set of sub-pixels of each pixel PX of the display panel DP. This controls the aperture ratio of each of the set of sub-pixels of each pixel PX. This allows the control device 100 to control the light transmittance of the set of sub-pixels of each pixel PX of the display panel DP. The display device 1000 also controls the output (lighting rate) of each light-emitting region ER of the backlight BL. This allows the control device 100 to control the luminance of each light-emitting region ER.

[0020] The control device 100 includes a panel control unit 50 as a component for controlling the display panel DP. The panel control unit 50 controls the gradations of the red, green, and blue sub-pixels of the display panel DP using input gradation information included in an input video signal received from the outside. This controls the luminance of each of the red, green, and blue sub-pixels. As a result, a full-color image or video is displayed on the display panel DP.

[0021] The control device 100 includes a backlight data generating section 40, an area memory (line memory) 30, a current integrating section 10, a current limit determining section 3, and a current suppressing section 20 as components for controlling the backlight BL.

[0022] The backlight data generator 40 uses the input grayscale of each pixel PX specified by the input video signal to generate backlight data that can specify the current flowing through each of all light-emitting areas ER. The backlight data is data that can specify the output (brightness or lighting rate) of each light-emitting area ER.

[0023] The area memory (line memory) 30 stores backlight data for each of a plurality of divided areas. In the present embodiment, one divided area is each line constituting a plurality of light emitting regions ER arranged in a matrix. Therefore, the area memory 30 is a line memory that stores backlight data for one line. However, the area memory 30 may be a block memory that stores backlight data for each divided area consisting of a block of light emitting regions ER arranged in three rows and three columns.

[0024] Area memory 30 sequentially updates the backlight data for each light emitting area ER of one line among all light emitting areas ER, and transmits the updated backlight data for the light emitting area ER of one line to output value calculation unit 5 of current suppression unit 20. In the present embodiment, one line is one row of the matrix, but it may also be one column of the matrix.

[0025] Current suppression unit 20 further adds the current value specified by the backlight data of one line of light emitting region ER stored in area memory 30 to the sum of currents specified by the backlight data of each light emitting region ER of all other lines of the same frame. Current suppression unit 20 outputs the sum of currents to backlight BL.

[0026] Specifically, the current accumulator 10 includes a new current accumulator 1, a temporary total value accumulator 2, a correction current accumulator 6, and a memory 7. The new current accumulator 1, the temporary total value accumulator 2, the correction current accumulator 6, and the memory 7 repeatedly execute the process described below every time one line of data among all backlight data is stored in the area memory 30.

[0027] The new current accumulation unit 1 calculates the value of the current flowing through one line of the light-emitting area ER using one line of backlight data extracted from all the backlight data generated by the backlight data generation unit 40, and transmits the calculated current value to the temporary total value accumulation unit 2.

[0028] Temporary total value accumulator 2 further adds the value of the current flowing in the light emitting area ER of the one line to the sum of the currents flowing in the light emitting areas ER of all other lines in the same frame other than the light emitting area ER of the one line. In this way, temporary total value accumulator 2 calculates the total value of the currents flowing in all light emitting areas ER. Temporary total value accumulator 2 transmits the total value to current limit determiner 3.

[0029] Current limit determination unit 3 determines whether the total value of the current flowing through light emitting area ER of all lines exceeds the upper limit of the current that can be passed through power supply circuit PW. Current limit determination unit 3 transmits the result of the determination as to whether the total value of the current flowing through light emitting area ER of all lines in the same frame exceeds the upper limit of the current that can be passed through power supply circuit PW to current suppression coefficient calculation unit 4 of current suppression unit 20.

[0030] There are cases where the total value of the current expected to flow through the light emitting areas ER of all lines in the same frame exceeds the upper limit of the current that can be passed through the power supply circuit PW. In this case, the current suppression unit 20 corrects the backlight data of each light emitting area ER of one line so that the total value of the current expected to flow through the light emitting areas ER of all lines of the backlight BL does not exceed the upper limit. Specifically, the current suppression unit 20 includes a current suppression coefficient calculation unit 4 and an output value calculation unit 5.

[0031] There are cases where it is determined that the total value of the currents expected to flow through the backlight BL exceeds the upper limit value. In this case, the current suppression coefficient calculation unit 4 calculates a current suppression coefficient for the one-line light emitting area ER to correct the backlight data for the one-line light emitting area ER so that the total value is equal to or less than the upper limit value.

[0032] The output value calculation unit 5 corrects the backlight data of one line of the light emitting area ER by multiplying the backlight data of the one line of the light emitting area ER by the current suppression coefficient. In addition, the output value calculation unit 5 transmits the corrected backlight data of the one line of the light emitting area ER to the backlight BL.

[0033] Thereby, in the backlight BL, the luminance of each light-emitting element constituting each of the plurality of light-emitting regions ER is controlled by all corrected backlight data including the corrected backlight data of one line of the light-emitting region ER output from the output value calculation unit 5. This corrected backlight data can prevent an overcurrent from flowing in the power supply circuit PW that guides a current to the backlight BL.

[0034] Furthermore, output value calculation unit 5 outputs the corrected backlight data of one line of light emitting region ER to correction current accumulator 6 of current accumulator 10. As a result, correction current accumulator 6 uses the corrected backlight data of the one line of light emitting region ER to calculate the total current value of all lines of light emitting region ER including the corrected current value of the one line of light emitting region ER, and stores the calculated total current value in memory 7.

[0035] Memory 7 transmits the corrected total value of the current in each light-emitting area ER of all lines to temporary total value accumulator 2. Temporary total value accumulator 2 further adds the current value flowing in the light-emitting area ER of one line accumulated in new current accumulator 1 to the sum of the currents flowing in the light-emitting areas ER of all lines other than the light-emitting area ER of that one line.

[0036] Fig. 2 is a diagram for explaining the backlight data correction process executed by the control device 100 of the display device 1000 according to the embodiment. In Fig. 2, the line data stored in the line memory is row data of a matrix. Also, in Fig. 2, the value of the current flowing through each light-emitting area ER is expressed as the lighting rate (%) of each light-emitting area ER.

[0037] In Fig. 2, in the N-1 frame (hereinafter, N is a natural number equal to or greater than 2), the light emitting areas ER in the top row and the second row from the top row are turned off, and the light emitting areas ER in the bottom row and the second row from the bottom row are illuminated at a lighting rate of 50%. In the N frame and the N+1 frame, the light emitting areas ER in the top row and the second row from the top row are illuminated at a lighting rate of 50%, and the light emitting areas ER in the bottom row and the second row from the bottom row are turned off. In other words, the area in which the light emitting areas ER are lit changes rapidly.

[0038] Each table in the upper row of FIG. 2 is the backlight data input to the backlight data generating unit 40, and each table in the lower row of FIG.

[0039] As shown in Fig. 2, when the backlight data of each light-emitting area ER in the bottom row of the N-1 frame is read, the total value of the current scheduled to flow through all light-emitting areas ER corresponding to the N-1 frame is calculated. In this embodiment, the value of the current scheduled to flow through the light-emitting area ER in each row of the N-1 frame is 0% in the second row from the top row, but 30% in the second row from the bottom row. Therefore, the total value of the current scheduled to flow through all light-emitting areas ER corresponding to the N-1 frame is 240%.

[0040] On the other hand, in this embodiment, the upper limit of the total value of the current that is actually allowed to flow through the power supply circuit PW is 240%. Therefore, even if the control device 100 controls the backlight BL using the backlight data of the N-1 frame, no overcurrent occurs in the power supply circuit PW that passes a current to the backlight BL. Therefore, the backlight data that the control device 100 outputs to the backlight BL is the backlight data itself generated from the input video signal in the backlight data generating unit 40. In other words, the control device 100 transmits the backlight data to the backlight BL without correction.

[0041] When control device 100 generates backlight data for the top light emitting region ER of the Nth frame, it calculates the total value of the current scheduled to flow through all light emitting regions ER corresponding to the Nth frame. In this embodiment, the value of the current scheduled to flow through the light emitting regions ER of each row of the Nth frame is 30% for the topmost row, the second-lowest row, and the bottommost row, but 0% for the second-highest row. Therefore, the total value of the current scheduled to flow through all light emitting regions ER of the Nth frame is 360%.

[0042] On the other hand, the upper limit of the total value of the current that is actually allowed to flow through the power supply circuit PW is 240%. Therefore, when the control device 100 controls the backlight BL using the backlight data of the Nth frame, an overcurrent occurs in the power supply circuit PW that passes a current through the backlight BL. Therefore, the control device 100 corrects the backlight data of the top row to correct the value of the current that is scheduled to flow through each light-emitting area ER corresponding to the top row from 30% to 0%.

[0043] As a result, if the control device 100 controls the backlight BL using the corrected backlight data corresponding to the Nth frame, no overcurrent occurs in the power supply circuit PW that supplies current to the backlight BL. Therefore, in this case, the control device 100 outputs the corrected backlight data (0%) of each light-emitting area ER in the top row to the backlight BL.

[0044] When control device 100 generates backlight data for each light-emitting region ER in the second row from the top of frame N, control device 100 calculates the total value of currents scheduled to flow through all light-emitting regions ER corresponding to frame N. In this embodiment, the value of currents scheduled to flow through light-emitting regions ER in each row of frame N is 30% in the second row from the top, the second row from the bottom, and the bottom row, but 0% in the top row. Therefore, the total value of currents scheduled to flow through all light-emitting regions ER in frame N is 360%.

[0045] On the other hand, the upper limit of the total current value actually allowed in the power supply circuit PW is 240%. Therefore, when the control device 100 controls the backlight BL using the backlight data of the Nth frame, an overcurrent occurs in the power supply circuit PW that passes a current to the backlight BL. Therefore, the control device 100 corrects the backlight data of the second row from the top row, thereby correcting the value of the current scheduled to pass through the light emitting area ER corresponding to the second row from the top row from 30% to 0%.

[0046] As a result, if the backlight BL is controlled using the corrected backlight data corresponding to the Nth frame, no overcurrent occurs in the power supply circuit PW that supplies current to the backlight BL. Therefore, in this case, the control device 100 outputs the corrected backlight data (0%) of each light-emitting area ER in the second row from the top to the backlight BL.

[0047] When control device 100 generates backlight data for the light emitting region ER in the third row from the top of frame N, it calculates the total value of the current scheduled to flow through all light emitting regions ER corresponding to frame N. The value of the current scheduled to flow through each row of light emitting regions ER in frame N is 0% in the top row, the second row from the top row, and the second row from the bottom row, but is 30% in the bottom row. Therefore, the total value of the current scheduled to flow through all light emitting regions ER corresponding to frame N is 120%.

[0048] On the other hand, the upper limit of the total value of the current that is actually allowed to flow through the power supply circuit PW is 240%. Therefore, even if the control device 100 controls the backlight BL using the backlight data of the Nth frame, an overcurrent does not occur in the power supply circuit PW that passes a current through the backlight BL. Therefore, in this case, the control device 100 outputs the backlight data of each light-emitting area ER in the third row from the top to the backlight BL without correcting it.

[0049] At the stage where backlight data for each light-emitting area ER in the bottom row of the Nth frame is generated, the total value of the current scheduled to flow through all light-emitting areas ER corresponding to the Nth frame is calculated. In this embodiment, the value of the current scheduled to flow through the light-emitting areas ER in each row of the Nth frame is 0% for the top row, the second row from the top row, the second row from the bottom row, and the bottom row. Therefore, the total value of the current scheduled to flow through all light-emitting areas ER corresponding to the Nth frame is 0%.

[0050] On the other hand, the upper limit of the total current that is actually allowed to flow through the power supply circuit PW is 240%. Therefore, even if the control device 100 controls the backlight BL using the backlight data of the Nth frame, an overcurrent does not occur in the power supply circuit PW that passes a current through the backlight BL. Therefore, in this case, the control device 100 outputs the backlight data of the bottom row of the light-emitting area ER to the backlight BL without correcting it.

[0051] When control device 100 generates backlight data for the top light-emitting region ER of frame N+1, control device 100 calculates the total value of the current scheduled to flow through all light-emitting regions ER corresponding to frame N+1. In this embodiment, the value of the current scheduled to flow through each row of light-emitting regions ER in frame N+1 is 30% for the top row and the second row from the top, but 0% for the bottom row and the second row from the bottom. Therefore, the total value of the current scheduled to flow through all light-emitting regions ER corresponding to frame N+1 is 240%.

[0052] On the other hand, the upper limit of the total value of the current that is actually allowed to flow through the power supply circuit PW is 240%. Therefore, even if the control device 100 controls the backlight BL using the backlight data of the N+1 frame, an overcurrent does not occur in the power supply circuit PW that passes a current through the backlight BL. Therefore, in this case, the control device 100 outputs the backlight data of the top row of the light emitting area ER to the backlight BL without correcting it.

[0053] According to the control shown in FIG. 2, since lighting of the backlight BL corresponding to the input video signal for one frame cannot be realized when switching between frames, the display quality is somewhat degraded, but no overcurrent occurs.

[0054] Fig. 3 is a first diagram for explaining the process for overcurrent detection executed by the control device 100 of the display device 1000 according to the embodiment. Fig. 4 is a second diagram for explaining the process for overcurrent detection executed by the control device 100 of the display device 1000 according to the embodiment.

[0055] 3, the backlight data for each frame includes line data corresponding to the light emitting regions ER of each line from the top row to the bottom row, that is, from the 1st line to the Lth line (L is a natural number equal to or greater than 3). When all processing of the 1st line to the Lth line in the N-1th frame is completed, processing of the 1st line to the Lth line in the Nth frame starts.

[0056] The current integrating unit 10 adds the following values ​​(1), (2), and (3) while incrementing p by 1 for the Nth frame.

[0057] (1) The sum of the currents to be flowed through the light-emitting areas ER of the updated p-1 line or more of the area memory 30 (if p is 1, this sum does not exist)

[0058] (2) The value of the current to be flowed through the light emitting area ER of the pth line being updated in the area memory 30 (1≦p≦L, p is a natural number, and L is the upper limit of p).

[0059] (3) The sum of the currents to be flowed through the light emitting areas ER of the p+1th line or less that have not been updated in the area memory 30 (if p is L, this sum does not exist) Specifically, the temporary total value accumulator 2 of the current accumulator 10 executes the calculation as shown in FIG.

[0060] Fig. 5 is a third diagram for explaining the process for overcurrent detection executed by the control device 100 of the display device 1000 according to the embodiment. Fig. 6 is a fourth diagram for explaining the process for overcurrent detection executed by the control device 100 of the display device 1000 according to the embodiment.

[0061] 5, the input data (backlight data) of N frames of the (x, y) divided area of ​​the matrix (line or block of the light emitting region ER) is defined as iData(x, y, N). The output data (backlight data or corrected backlight data) of N frames of the (x, y) divided area of ​​the matrix (line or block of the light emitting region ER) is defined as oData(x, y, N).

[0062] Let the total of input data (backlight data) for N frames and y lines be iLtotal(y,N). Let the total of output data (backlight data or corrected backlight data) for N frames and y lines be oLtotal(y,N).

[0063] Under the definition shown in Fig. 5 above, the current limit determination unit 3 executes the determination shown in Fig. 6. Moreover, the current suppression unit 20 executes the calculation shown in Fig. 6.

[0064] Fig. 7 is a diagram for explaining an aspect in which overcurrent detection is suppressed by processing executed by the control device 100 of the display device 1000 of the embodiment. 50% in Fig. 7 indicates the lighting rate of the light-emitting area ER of the backlight BL. In Fig. 7, a white area indicates that the light-emitting area ER is lit, and a gray area indicates that the light-emitting area ER is unlit.

[0065] As shown in Figure 7, from the relationship between the total value of the current flowing through the power supply circuit PW and time, it can be seen that the occurrence of overcurrent as shown by the dotted line is suppressed, and a stable current as shown by the solid line flows through the power supply circuit PW which supplies current to the backlight BL.

[0066] The characteristic configuration of the display device 1000 of this embodiment and the effects obtained thereby can be summarized as follows.

[0067] (1) As shown in Fig. 1, the display device 1000 includes a backlight BL and a control device 100. The backlight BL includes a plurality of light-emitting regions ER that are divided into a plurality of divided areas (rows: lines). The control device 100 controls the backlight BL based on backlight data acquired from video data having a plurality of frames.

[0068] The control device 100 updates the backlight data from the current frame (N-1 frame) to the next frame (N frame) of the multiple frames for each of the multiple divided areas. This is called an update period (see the thick frame in FIG. 2). During the update period, the backlight data of the current frame and the backlight data of the next frame may be mixed (see FIG. 3). In this case, if the current value (the total value of the currents expected to flow through the multiple light-emitting regions ER) related to the backlight BL is greater than a predetermined value, the control device 100 corrects the backlight data of the next frame during the update period to lower the current value. The control device 100 controls the backlight BL based on the corrected backlight data of the next frame.

[0069] According to the above configuration, it is possible to prevent an overcurrent from flowing through the power supply circuit PW that guides a current to the backlight BL.

[0070] (2) Specifically, control device 100 may determine whether or not the sum of the currents flowing through all or some of the light-emitting regions ER (see TOTAL in FIG. 2) exceeds an upper limit (see 240% in FIG. 2) during the update period. If the sum exceeds the upper limit, control device 100 may correct the backlight data for the next frame (Nth frame) during the update period so that the sum becomes equal to or less than the upper limit.

[0071] This makes it possible to prevent an overcurrent from occurring in the power supply circuit PW by utilizing the sum of the currents expected to flow through all or some of the multiple light emitting regions ER.

[0072] (3) As shown in FIG. 1, the control device 100 may include an area memory 30, a current integrator 10, a current limit determiner 3, a current suppression coefficient calculator 4, and an output value calculator 5.

[0073] As shown in FIG. 3, the area memory (line memory) 30 sequentially updates the backlight data of the current frame (N-1 frame) to the backlight data of the next frame. As shown in FIG. 4, the current integrator 10 calculates an addition value every time the backlight data of each of the multiple divided areas is updated in the area memory 30. As shown in FIG. 6, the current limit determination unit 3 determines whether the addition value exceeds an upper limit value. When the addition value exceeds the upper limit value, the current suppression coefficient calculation unit 4 calculates a current suppression coefficient for correcting the backlight data so that the addition value is equal to or less than the upper limit value. As shown in FIG. 6, the output value calculation unit 5 corrects the backlight BL of the next frame (N frame) in the above-mentioned update period by multiplying the backlight data of the next frame by the current suppression coefficient. Thereafter, as shown in FIG. 5, the output value calculation unit 5 outputs the corrected backlight data of the next frame (N frame).

[0074] According to the above configuration, by adjusting the current suppression coefficient, it is possible to effectively suppress the occurrence of an overcurrent in the power supply circuit PW.

[0075] (4) In display device 1000, a plurality of light emitting regions ER are arranged in a matrix as shown in Fig. 1. As shown in Fig. 2, each of the plurality of divided areas includes two or more light emitting regions ER included in one line that constitutes the matrix. Area memory 30 may sequentially update line data that can identify the value of a line current flowing through two or more light emitting regions ER included in one line.

[0076] According to the above configuration, every time the value of the estimated current flowing through one line of light emitting area ER is generated, it is possible to prevent an overcurrent from occurring in power supply circuit PW.

[0077] (5) The line memory may sequentially update line data from a line at one end of the matrix to a line at the other end of the matrix, as shown in FIG.

[0078] According to the above configuration, it is possible to prevent an overcurrent from occurring in the power supply circuit PW every time video data is updated in sequence from a line at one end to a line at the other end.

[0079] (6) As shown in FIG. 4, the current integrator 10 may calculate the above-mentioned sum by adding up the values ​​of the area currents flowing through each of the multiple divided areas.

[0080] According to the above configuration, the above-mentioned added value can be easily calculated.

[0081] (7) A method for controlling the display device 1000 according to the embodiment includes the steps of executing the operations of the respective units described in any one of (1) to (6) above. [Explanation of symbols]

[0082] 100 Control device 1000 display devices BL Backlight DP display panel

Claims

1. A backlight including a plurality of light-emitting regions divided into a plurality of divided areas; a control device that controls the backlight based on backlight data obtained from video data having a plurality of frames; The control device includes: during an update period in which the backlight data is updated from a current frame to a next frame among the plurality of frames for each of the plurality of divided areas, when the backlight data of the current frame and the backlight data of the next frame are mixed, if a current value related to the backlight is greater than a predetermined value, correcting the backlight data of the next frame during the update period so as to reduce the current value; The backlight is controlled based on the corrected backlight data of the next frame. Display device.

2. The control device includes: During the renewal period, determining whether or not a sum of the currents flowing through all or some of the plurality of light-emitting regions as the current value exceeds an upper limit value; if the added value exceeds the upper limit value, correcting the backlight data of the next frame in the update period so that the added value becomes equal to or less than the upper limit value; The display device according to claim 1 .

3. The control device includes: an area memory for sequentially updating the backlight data of the current frame to the backlight data of the next frame; a current integrator that calculates the added value each time the backlight data for each of the divided areas is updated in the area memory; a current limit determination unit that determines whether the added value exceeds the upper limit value; a current suppression coefficient calculation unit that calculates a current suppression coefficient for correcting the backlight data when the added value exceeds the upper limit value so that the added value becomes equal to or less than the upper limit value; and an output value calculation unit that corrects the backlight data of the next frame in the update period by multiplying the backlight data of the next frame by the current suppression coefficient, and outputs the corrected backlight data of the next frame. The display device according to claim 2 .

4. The plurality of light emitting regions are arranged in a matrix, Each of the plurality of divided areas includes two or more light emitting regions included in one line constituting the matrix, the area memory is a line memory that sequentially updates line data that can specify a value of a line current flowing through the two or more light-emitting areas included in the one line; The display device according to claim 3 .

5. the line memory sequentially updates the line data from a line at one end of the matrix to a line at the other end of the matrix; The display device according to claim 4.

6. the current integrator calculates the sum by adding up values ​​of area currents flowing through the plurality of divided areas; The display device according to claim 3 .

7. A backlight including a plurality of light-emitting regions divided into a plurality of divided areas; A control device that controls a backlight based on backlight data obtained from video data having a plurality of frames, comprising: The control device includes: a step of correcting the backlight data of the next frame in an update period in which the backlight data is updated from a current frame to a next frame among the plurality of frames for each of the plurality of divided areas, when the backlight data of the current frame and the backlight data of the next frame are mixed and a current value related to the backlight is greater than a predetermined value; and controlling the backlight based on the corrected backlight data of the next frame. A method for controlling a display device.

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