JP2017076110A - Display device and control method and program for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device capable of controlling a lighting luminance of a backlight in a preferable manner upon displaying an image having a locally bright region, and a method for controlling the display device.SOLUTION: A display device 100 of the present invention includes: a plurality of light-emitting units projecting light; a liquid crystal panel 7 for displaying an image on a screen; a luminance value acquisition unit 62 for acquiring a luminance value of each light-emitting unit based on a representative luminance value representing brightness of a region in an input image 10 corresponding to each light-emitting unit; an HPF processing unit 63a for acquiring an HPF luminance value of each light-emitting unit through a computation process of increasing the emission luminance value of a target light-emitting unit with the smaller value of the emission luminance of a light-emitting unit in a periphery of the target light-emitting unit in the plurality of light-emitting units compared to the emission luminance value of the target light-emitting part; a smoothing processing unit 63b for acquiring a corrected luminance value of each light-emitting unit through a computation process of smoothing a distribution of the HPF luminance values; and a light-emission control unit 65 for controlling light emission of each light-emitting unit by using the corrected luminance values of each light-emitting unit.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a display device having a lighting device, a control method therefor, and a program.

  In a display device including a transmissive display panel and a backlight, the display panel transmits light emitted from the backlight to the display panel and displays an image. In addition, the backlight includes a plurality of light emitting units capable of individually controlling the light emission luminance, and the luminance of light emitted from the light emitting unit (in accordance with the brightness of the image displayed in the area of the display panel corresponding to each light emitting unit ( There is a technique for controlling (emission luminance).

  In the display device described above, part of the light emitted from the light emitting unit diffuses to a region around the region of the display panel corresponding to the light emitting unit. Therefore, when the above display device displays an image having a locally brighter image than the surrounding image, a part of the light emitted from the light emitting unit corresponding to the area where the bright image is displayed is diffused, There may be a shortage of brightness required to express a bright image.

  In Patent Document 1, when an input image corresponding to a certain light emitting unit among a plurality of light emitting units of a backlight includes a pixel having a high gradation value, a technique for increasing the light emission luminance of the light emitting units around the light emitting unit. Is disclosed. Thereby, when displaying an image having a bright image locally, it is possible to supplement the luminance of the light applied to the area of the display panel on which the bright image is displayed by the light emission of the surrounding light emitting units.

International Publication No. 2011-013402

  However, in the conventional technique described above, when an image including a locally bright image (partial high brightness region) is displayed in a dark image, the dark image around the bright image is expressed by leakage light. In some cases, the phenomenon of falling black floating occurs.

  Therefore, in view of the above problems, the present invention provides a display device capable of suitably controlling the light emission luminance of a backlight when displaying an image including a partial high luminance region, and a control method therefor. For the purpose.

  In order to solve the above-described problems, a display device according to the present invention includes a plurality of light emitting units that irradiate light, a display unit that transmits light irradiated based on an input image and displays an image on a screen, A first acquisition unit configured to acquire a first luminance value of each light emitting unit based on a luminance of a region of the input image corresponding to the light emitting unit; and the first luminance of a first attention light emitting unit among the plurality of light emitting units. When the value is larger than the first luminance value of the first adjacent light emitting unit adjacent to the first target light emitting unit, the first luminance value of the first target light emitting unit is set to the first target light emitting unit. First processing means for obtaining second brightness values of the plurality of light emitting means by increasing according to a difference between the first brightness value of the light emitting means and the first brightness value of the first adjacent light emitting means; Among the plurality of light emitting means, the second luminance value of the second attention light emitting means is When the second luminance value of the second adjacent light emitting means is smaller than the second luminance value of the second adjacent light emitting means, the second luminance value of the second attention light emitting means is set to the second attention light emitting means. A second processing means for obtaining a third brightness value of the plurality of light emitting means by increasing according to a difference between the second brightness value and the second brightness value of the second adjacent light emitting means; and each light emitting means. Control means for controlling the light emission of each light emitting means using the third luminance value.

  According to the display device of the present invention, it is possible to suitably control the lighting brightness of the backlight when displaying an image including a partial high-luminance region.

It is an apparatus block diagram of the display apparatus in a 1st Example. It is a schematic diagram which shows the backlight in a 1st Example. It is a 1st block diagram which shows the functional block of the display apparatus in a 1st Example. It is the figure which showed the luminance reference information which linked | related the representative luminance value and the light emission luminance value. It is a schematic diagram which shows an input image. It is the schematic diagram which showed the representative luminance value of the area | region of a corresponding input image with respect to each light emission part of a backlight. It is the schematic diagram which showed the light emission luminance value which the luminance value acquisition part acquired with respect to each light emission part of a backlight. It is the schematic diagram which showed the HPF light emission luminance value which the HPF process part acquired with respect to each light emission part of a backlight. It is the schematic diagram which showed the correction | amendment light emission luminance value which the smoothing process part acquired with respect to each light emission part of a backlight. It is the schematic diagram which showed the brightness | luminance of the light irradiated to the display area of the liquid crystal panel corresponding to light emission part A4-J4. It is a 2nd block diagram which shows the functional block of the display apparatus in a 2nd Example. It is the schematic diagram which showed estimated brightness | luminance and required brightness | luminance with respect to display area A4-J4. It is the schematic diagram which showed the brightness | luminance of the light irradiated to the display area of the liquid crystal panel corresponding to light emission part A4-J4. It is a 3rd block diagram which shows the functional block of the display apparatus in a 3rd Example. It is the schematic diagram which showed the brightness | luminance of the light irradiated to the display area of the liquid crystal panel corresponding to light emission part A4-J4 in the case of the input image shown in FIG. It is the schematic diagram which showed the brightness | luminance of the light irradiated to the display area of the liquid crystal panel corresponding to light emission part A4-J4 in case an input image is all white. It is a 4th block diagram which shows the functional block of the display apparatus in a 4th Example. It is a schematic diagram which shows the relationship between APL of a correction coefficient determination part, and a luminance correction coefficient.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The technical scope of the present invention is determined by the scope of claims, and is not limited by the examples illustrated below. Further, not all the combinations of features described in the embodiments are essential to the present invention. The contents described in this specification and drawings are illustrative and should not be construed as limiting the present invention. Various modifications (including organic combinations of the embodiments) are possible based on the spirit of the present invention, and they are not excluded from the scope of the present invention.

(First embodiment)
FIG. 1 is a device configuration diagram of a display device 100 according to the first embodiment. The display device 100 includes an input interface 1, a processor 2, a memory 3, an internal storage 4, a display control unit 5, a backlight control unit 6, a liquid crystal panel 7, a backlight 8, and a bus line 9.

  The input interface 1 is an interface that connects the display device 100 and the external output device 500. The input interface 1 outputs an image input from the external output device 500 to the processor 2 and the memory 3 via the bus line 9.

  The input interface 1 is an input port corresponding to a standard such as Digital Visual Interface (DVI) or High-Definition Multimedia Interface (HDMI (registered trademark)). Further, the input interface 1 may be a reception interface capable of receiving a signal conforming to a wireless communication standard such as Wireless Fidelity (Wi-Fi) or Bluetooth (registered trademark). Further, the input interface 1 may have a function of converting an input or received signal into a signal format that can be processed by the processor 2, the display control unit 5, and the backlight control unit 6.

  Here, the external output device 500 is a device that is connected to the input interface 1 of the display device 100 and can output an image. Specifically, the external output device 500 includes an imaging device such as a camera that can output a captured image, a recorder that has a storage medium that can store the image, and that can output the stored image, or a personal computer (PC). Etc.

  The processor 2 is a processing device that controls the operation of the display device 100. The processor 2 is an arithmetic processing unit such as a central processing unit (CPU) or a micro processing unit (MPU). At this time, the processor 2 executes the program read from the memory 3 and controls the operations of the display control unit 5 and the backlight control unit 6.

  Note that the processor 2 can perform the same processing as part or all of the functions of the display control unit 5 and the backlight control unit 6 described later by executing the program read from the memory 3. Further, the processor 2 can read out an image from the internal storage 4 by executing a program read out from the memory 3 and output the image to the display control unit 5 and the backlight control unit 6. A plurality of processors 2 may be arranged.

  The memory 3 is a storage medium that can read and write data. The memory 3 stores programs, parameters, and the like that can be executed by the processor 2 that the processor 2 uses to control the display device 100. The memory 3 is a non-volatile storage medium such as a hard disk or a volatile storage medium such as a semiconductor memory.

  The internal storage 4 is a storage medium such as a hard disk drive. The internal storage 4 stores an image displayed on the display device 100 and outputs the image to the processor 2 and the memory 3 via the bus line 9. The internal storage 4 may store a program used by the processor 2 for controlling the display device 100.

  The display control unit 5 is a control circuit board that controls the liquid crystal panel 7 based on an input image. The display control unit 5 performs image processing on at least a part of the input image, generates a display image, and controls a plurality of liquid crystal elements included in the liquid crystal panel 7 based on the display image. In addition, the display control unit 5 includes a plurality of circuit modules that exhibit the functions of the functional blocks described later in order to execute the above-described processing. Each circuit module performs its function. The display control unit 5 may include an arithmetic processing device (computer) capable of executing a program for exhibiting at least one function of each functional block described later.

  The backlight control unit 6 is a control circuit board that controls the backlight 8 based on the input image. Specifically, the backlight control unit 6 determines a luminance setting value indicating the light emission amount of the backlight 8 according to the luminance of the input image, and a control signal for the backlight 8 based on the determined light emission luminance. To decide. The backlight control unit 6 includes a plurality of circuit modules as will be described later in order to execute the above-described processing. Each circuit module performs its function.

  The liquid crystal panel 7 is a transmissive display panel having a plurality of liquid crystal elements capable of individually controlling the light transmittance. The liquid crystal panel 7 controls the transmittance of each liquid crystal element according to the input image, transmits the light emitted from the backlight 8, and displays the image on the screen on the front side of the liquid crystal panel 7. In this way, the display control unit 5 controls.

  Each liquid crystal element of the liquid crystal panel 7 changes in transmittance according to the gradation value of the corresponding pixel in the input image. In the first embodiment, the transmittance of the liquid crystal element increases linearly with an increase in gradation value. The liquid crystal panel 7 may be a transmissive display panel, and may be a display panel having a plurality of shutter elements using Micro Electro Mechanical Systems (MEMS).

  The backlight 8 is a lighting device having a plurality of light emitting units. The backlight 8 is disposed on the back side of the liquid crystal panel 7 and irradiates the liquid crystal panel 7 with light from a plurality of light emitting units. Each light emitting section includes a light source 8a, and lighting can be controlled for each light emitting section. In other words, it can be said that the backlight 8 is an illuminating device including a plurality of light emitting units capable of individually controlling the light emission luminance. Each light emitting unit of the backlight 8 is controlled by the backlight control unit 6 using a luminance setting value determined based on the input image.

  FIG. 2 is a schematic diagram showing the backlight 8 in the first embodiment. The backlight 8 includes light emitting units arranged in a matrix of 7 (1 to 7) in the vertical direction and 10 (A to J) in the horizontal direction with respect to the screen of the display device 100. Each light emitting unit is described separately using a position (A to J) in the horizontal direction and a position (1 to 7) in the vertical direction. For example, the upper right light emitting part in FIG. 2 is indicated as a light emitting part J7. The number and arrangement of the light emitting units included in the backlight 8 are not limited to the above-described configuration, and can be arbitrarily set by the designer depending on the size, function, and the like of the display device 100.

  The bus line 9 is a common communication line used for connection among the input interface 1, the processor 2, the memory 3, the internal storage 4, the display control unit 5, and the backlight control unit 6. Information such as input images and programs used by the processor 2 is exchanged through the bus line 9.

  FIG. 3 is a block diagram illustrating functional blocks of the display device 100 according to the first embodiment. FIG. 3 shows circuit modules provided in the display control unit 5 and the backlight control unit 6 of the display device 100, respectively.

  The display control unit 5 includes an irradiation luminance estimation unit 51 and an image correction unit 52. The backlight control unit 6 includes a representative luminance acquisition unit 61, a luminance value acquisition unit 62, a luminance correction unit 63, a luminance determination unit 64, and a light emission control unit 65. The luminance correction unit 63 includes a high pass filter (HPF) processing unit 63a and a smoothing processing unit 63b.

  Each circuit module includes at least one of an electronic circuit and an arithmetic processing circuit. Each circuit module can transmit / receive information to / from the processor 2 and the memory 3 via the bus line 9. The processor 2 may execute a program read from the memory 3 and control the operation of each circuit module. The functions exhibited by the respective circuit modules may be realized by the processor 2 executing a program read from the memory 3 instead of the circuit module provided in the display control unit 5 or the backlight control unit 6.

  The input interface 1 outputs the input image to the representative luminance acquisition unit 61 and the image correction unit 52. The input image is data in which gradation values are designated for each pixel arranged in a matrix. In the first embodiment, the gradation value of each pixel of the input image is described by 8-bit data from 0 to 255. Note that the input image encoding method, the number of display bits, and the like are not limited to the above example.

  Further, the input interface 1 may output an image obtained by performing predetermined gradation conversion or the like on the input image to the representative luminance acquisition unit 61 and the image correction unit 52. Hereinafter, an image input to the input interface 1 and an image input to the input interface 1 and subjected to processing such as predetermined gradation conversion are collectively referred to as an input image. The input image may be input from the internal storage 4.

  The representative luminance acquisition unit 61 acquires a representative luminance value used for determining the light emission luminance value of each light emitting unit for each region of the input image corresponding to each light emitting unit. The representative luminance acquisition unit 61 acquires a representative luminance value for each region of the input image corresponding to each light emitting unit of the backlight 8, and outputs the position of each region and the representative luminance value to the light emission luminance value acquiring unit 103. In the first embodiment, the representative luminance value is the maximum gradation value of the image. The representative luminance value is a parameter (feature amount) indicating the brightness (luminance) of the image. The representative luminance value may be an average gradation value of the image. In addition, when the image designates display luminance for each pixel, the representative luminance value may be maximum luminance or average luminance.

  The luminance value acquisition unit 62 acquires the emission luminance value of the corresponding light emitting unit according to the representative luminance value of the area of the input image corresponding to each light emitting unit. Further, the luminance value acquisition unit 62 outputs the acquired light emission luminance value to the luminance correction unit 63. The luminance value acquisition unit 62 acquires the light emission luminance value from the representative luminance value based on the luminance reference information that associates the representative luminance value and the light emission luminance value. In the first embodiment, the luminance reference information is a look-up table (LUT) that associates luminance characteristics with emission luminance values.

  FIG. 4 is a diagram showing luminance reference information in which the representative luminance value and the light emission luminance value are associated in the first embodiment. The horizontal axis in FIG. 4 indicates the representative luminance value. Therefore, the range of the horizontal axis is 0 to 255. The vertical axis in FIG. 4 indicates the light emission luminance value. The light emission luminance value is shown as a ratio of the light emission luminance with respect to the maximum light emission luminance at which each light emitting unit of the backlight 8 can be turned on. In the first embodiment, when all of the light emitting portions of the backlight 8 are turned on with the maximum light emission luminance, the liquid crystal panel 7 is irradiated with light having a luminance of 2000 cd / m2.

  In the luminance reference information, the emission luminance value 10% is associated with the minimum value (0) that the representative luminance value can take, and the emission luminance value 50 with respect to the maximum value (255) that the representative luminance value can take. % Are associated. In the luminance reference information, the emission luminance values are associated with each other so as to increase linearly as the representative luminance value increases.

  In this case, when the input image is an all-black image, all the light emitting portions of the backlight 8 are lit with a light emission luminance value of 10%, and the luminance (irradiation luminance) of light irradiated on the liquid crystal panel 7 is 200 cd. / M2. When the input image is an all-white image, all the light emitting portions of the backlight 8 are turned on with a light emission luminance value of 50%, and the irradiation luminance of the liquid crystal panel 7 is 1000 cd / m 2.

  The light emission luminance value with respect to the maximum value that the representative luminance value can take is obtained from the irradiation luminance required for displaying the maximum display luminance of the display device 100. When the light transmittance of the liquid crystal element at the maximum gradation value is 10% and the maximum display luminance setting value of the display device 100 is 100 cd / m 2, the emission luminance value with respect to the maximum value that the representative luminance value can take is , 1000 cd / m2. The maximum display brightness of the display device 100 can be arbitrarily set by a user or a designer.

  Further, the luminance reference information is not limited to the above-described form, and may be a conversion formula for calculating the light emission luminance value from the representative luminance value. The luminance value acquisition unit 62 acquires the emission luminance value of the corresponding light emitting unit from the representative luminance value of the region corresponding to each light emitting unit and the luminance reference information.

  The luminance correction unit 63 corrects the light emission luminance value of each light emitting unit and outputs the corrected light emission luminance value to the luminance determination unit 64. The luminance correction unit 63 emits the luminance of the target light emitting unit according to the difference between the light emission luminance value of the target light emitting unit among the plurality of light emitting units and the light emission luminance value of the peripheral light emitting unit disposed around the target light emitting unit. The value is corrected to obtain the corrected light emission luminance value of the target light emitting unit. The light emission luminance value of the target light emitting unit is greater than the light emission luminance value of at least one peripheral light emitting unit, and the difference between the light emission luminance value of the target light emitting unit and the light emission luminance value of the peripheral light emitting unit is greater than or equal to a predetermined value The brightness correction unit 63 increases the corrected light emission luminance value of the light emitting unit of interest as compared to the case where it is not. The luminance correction unit 63 acquires a corrected light emission luminance value for each light emitting unit of the backlight 8.

  Using the corrected light emission luminance value acquired as described above, the light emitted from each light emitting unit of the backlight 8 to the liquid crystal panel 7 is used to illuminate the region of the liquid crystal panel 7 corresponding to the target light emitting unit. It is possible to suppress the shortage. In addition, since it is possible to suppress an excessive increase in the light emission luminance of the peripheral light emitting unit, it is possible to suppress the occurrence of black floating when a dark image is displayed in an area corresponding to the peripheral light emitting unit. Become.

  The HPF processing unit 63a performs a process of relatively increasing the light emission luminance value of the target light emitting unit according to the difference between the light emission luminance value of a certain light emitting unit and the light emission luminance value of the peripheral light emitting unit among the plurality of light emitting units. Apply. Specifically, the HPF processing unit 63a performs HPF processing in which a high-frequency component is spatially emphasized with respect to the distribution of the acquired emission luminance values among the emission luminance values of the respective light emitting units, thereby obtaining an HPF emission luminance value. To get. A large difference between the light emission luminance value of the target light emitting unit and the light emission luminance value of the peripheral light emitting unit means that there is a spatial high-frequency component of the light emission luminance value of the target light emitting unit.

  The HPF processing unit 63a outputs the HPF emission luminance value to the smoothing processing unit 63b. In the HPF process, the light emission luminance values of light emitting units arranged in a matrix of a × b (a and b are integers) centered on one target light emitting unit among a plurality of light emitting units are set to a × b. This is a process for emphasizing high-frequency components by the filter operation.

  The HPF process is not limited to the method described above. It may be a process of performing differential detection processing on the light emission luminance value and emphasizing the light emission luminance value using the detected edge component. The HPF processing can use high-frequency component enhancement processing that is generally used in the field of image processing. The HPF process may use another processing method as long as the high-frequency component is spatially emphasized.

  Further, the HPF process relatively reduces the light emission luminance value of the target light emitting unit when the light emission luminance value of a target light emitting unit among the plurality of light emitting units is larger than the light emission luminance value of the peripheral light emitting unit by a predetermined level or more. It can be substituted by a process of increasing. The HPF processing unit 63a outputs an HPF light emission luminance value obtained by performing HPF processing on each light emitting unit to the smoothing processing unit 63b.

  The smoothing processing unit 63b performs a process of increasing the HPF light emission luminance value of the light emitting unit whose HPF light emission luminance value is smaller than the corresponding light emission luminance value by the HPF processing unit 63b. The smoothing processing unit 63b performs a smoothing process on the acquired HPF light emission luminance value, and acquires a corrected light emission luminance value. The smoothing processing unit 63b compares the HPF emission luminance value of one target light emitting unit among the plurality of light emitting units with the HPF emission luminance value of the adjacent light emitting unit adjacent to the target light emitting unit. (In the embodiment, “adjacent” does not need to be in contact, and includes those adjacent to each other with a gap.) Adjacent light emitting unit having an HPF emission luminance value higher than the HPF emission luminance value of the light emitting unit of interest If there is, the smoothing processing unit 63b increases the HPF light emission luminance value of the target light emitting unit.

  The smoothing process is not limited to the above-described method, and may be any process that compensates for the shortage of the HPF light emission luminance value. For example, the smoothing process may perform a low pass filter (LPF) process that spatially emphasizes a low frequency component by using a filter operation. The smoothing processing unit 63 performs a smoothing process on the HPF light emission luminance value of each light emitting unit, and outputs the acquired corrected light emission luminance value to the luminance determining unit 64.

  Note that the method by which the luminance correction unit 63 corrects the light emission luminance value of each light emitting unit to the corrected light emission luminance value is not limited to the method described above. The luminance correction unit 63 corrects the light emission luminance value of the target light emitting unit based on the difference between the light emission luminance value of the target light emitting unit and the light emission luminance value of the peripheral light emitting unit, and the corrected light emission luminance value of the target light emitting unit It is also possible to do. That is, the luminance correction unit 63 increases the emission luminance value of the target light emitting unit according to the difference between the light emission luminance value of the target light emitting unit and the light emission luminance value of the peripheral light emitting unit, thereby correcting the corrected light emission luminance value of the target light emitting unit. It becomes.

  The luminance correction unit 63 sets each light emitting unit as a target light emitting unit, and if the light emitting luminance value of the target light emitting unit is higher than the light emitting luminance value of the peripheral light emitting unit by a predetermined value or more, the luminance correcting unit 63 Processing that is higher than that in the case of not being may be performed. The predetermined value can be arbitrarily set by a user or a designer.

  The luminance correction unit 63 calculates the root mean square of the differences from the respective emission luminance values of the eight peripheral light emitting units adjacent to the target light emitting unit in the vertical and horizontal directions, and in the oblique direction, and adds the result to the light emission luminance value of the target light emitting unit. Correction may be performed. Accordingly, the luminance correction unit 63 increases the light emission luminance value of the target light emitting unit to obtain the corrected light emission luminance value as the light emission luminance value of the peripheral light emitting unit is smaller than the light emission luminance value of the target light emitting unit. The peripheral light emitting unit used for calculating the mean square may be a light emitting unit excluding the target light emitting units arranged in a 5 × 5 matrix centered on the target light emitting unit. At this time, the corrected light emission luminance value may be calculated by weighting the light emission luminance value according to the distance from the target light emitting unit.

  In addition, the luminance correction unit 63 compares the light emission luminance value of the light emitting unit of interest with the light emission luminance value of the peripheral light emitting unit, and increases the light emission luminance value of the light emitting unit of interest when the difference is equal to or greater than a predetermined level. Correction may be performed to calculate a corrected light emission luminance value.

  That is, according to the correction process performed by the luminance correction unit 63, when the light emission luminance value of the peripheral light emitting unit is larger than the light emission luminance value of the target light emitting unit, the corrected light emission luminance value of the target light emitting unit is The light emission luminance value of the target light emission unit is increased according to the difference in the light emission luminance value from the light emission unit. Further, according to the correction process executed by the luminance correction unit 63, when the light emission luminance value of the peripheral light emitting unit is smaller than the light emission luminance value of the target light emitting unit, the corrected light emission luminance value of the target light emitting unit is The light emission luminance value of the target light emission unit is increased according to the difference in the light emission luminance value from the light emission unit.

  The luminance determination unit 64 determines the luminance setting value of each light emitting unit of the backlight 8 based on the acquired corrected light emission luminance value. The luminance setting value is indicated as a ratio of the light emission luminance to the maximum light emission luminance that can be turned on by the respective light emitting units of the backlight 8, similarly to the respective light emission luminance values. The luminance determination unit 64 determines the corrected light emission luminance value as a luminance setting value. Note that the luminance determining unit 64 can determine the luminance setting value by performing correction or the like for reducing the influence of external light on the corrected light emission luminance value. The luminance determination unit 64 outputs the luminance setting value to the irradiation luminance estimation unit 51 and the light emission control unit 65.

  The light emission control unit 65 controls the light emission luminance of each light emitting unit of the backlight 8 based on the luminance setting value. When the light emission amount of the light emitting unit is controlled by pulse width modulation (PWM), the light emission control unit 65 uses the pulse width modulation duty ratio (ratio between the lighting period and the extinguishing period) based on the luminance setting value. Is determined as control information. Moreover, the light emission control part 65 may control the light emission amount of each light emission part by setting the drive voltage value or drive current value of each light emission part. In this case, the drive voltage value or the drive current value is determined as control information based on the brightness setting value.

  The light emission control unit 65 may control the light emission luminance of the light emitting unit by pulse width modulation and control of the driving voltage value or driving current value of the light emitting unit. In that case, based on the brightness setting value, the duty ratio of the pulse width modulation (ratio between the lighting period and the extinguishing period) and the driving voltage value or driving current value are determined. The light emission control unit 65 outputs the determined control information to the backlight 8 and controls the light emission luminance of each light emitting unit of the backlight 8.

  The irradiation luminance estimation unit 51 uses the luminance setting value acquired from the luminance determination unit 64 to acquire the irradiation luminance used by the image correction unit 52 to correct the input image. The illumination brightness is the brightness of light applied to the liquid crystal panel 7 when each light emitting unit of the backlight 8 is turned on using the brightness setting value.

  The irradiation luminance estimation unit 51 estimates the irradiation luminance at the center of the display area of the liquid crystal panel 7 corresponding to each light emitting unit. The irradiation luminance estimation unit 51 acquires, from the memory 3, diffusion information indicating a rate at which light is diffused to a display area corresponding to a surrounding light emitting unit when light is emitted from one light emitting unit.

  The irradiation luminance estimation unit 51 estimates the irradiation luminance at the center of each display area of the liquid crystal panel 7 acquired using the luminance setting value and diffusion information of each light emitting unit. Further, the irradiation luminance estimation unit 51 can also estimate the distribution of irradiation luminance by interpolating the irradiation luminance at the center of each display area. The irradiation luminance estimation unit 51 outputs the acquired irradiation luminance to the image correction unit 52.

The image correction unit 52 corrects the input image using the acquired irradiation luminance, generates a display image, and outputs the display image to the panel control unit 53. When the irradiation luminance of the display area corresponding to a certain light emitting unit is Lpn, the image correcting unit 52 determines the correction coefficient Gpn using the reference luminance Lt of the light emitting unit. The reference luminance Lt is an emission luminance value associated with the gradation value 255, and is an irradiation luminance when all the light emitting units are controlled. That is, the reference luminance Lt in the first embodiment is 1000 cd / m2. Expression 1 is an expression for determining the correction coefficient Gpn.
Gpn = Lt / Lpn (Formula 1)

  The image correction unit 52 uses the correction coefficient Gpn determined for each display area to correct the gradation value of the input image displayed in the corresponding display area to obtain the gradation value of the display image. The image correction unit 52 multiplies the gradation value of the input image displayed in the same display area by the correction coefficient Gpn of the corresponding display area. Further, the image correction unit 52 may multiply the gradation value of the input image by a value obtained by interpolating the correction coefficient between the display areas using the correction coefficient Gpn of the adjacent display area.

  The panel control unit 53 controls the transmittance of each liquid crystal element of the liquid crystal panel 7 based on the display image acquired from the image correction unit 52. Specifically, the panel control unit 53 controls the voltage applied to each liquid crystal element according to the gradation value of the display image. The light emitted from the backlight 8 is transmitted through each liquid crystal element, whereby an image is displayed on the liquid crystal panel 7.

  Hereinafter, the backlight control process in the display device 100 will be specifically described. FIG. 5 is a schematic diagram illustrating the input image 10 output from the input interface 1 to the image correction unit 52 and the representative luminance acquisition unit 61. Regions indicated by dotted lines in FIG. 5 indicate regions of the input image corresponding to the respective light emitting units of the backlight 8 illustrated in FIG. Hereinafter, each area of the input image is denoted as areas A1 to J7 depending on the position, like the light emitting unit.

  In the first embodiment, the input image 10 has a bright image in the region B4. The input image 10 has bright images in the areas G2 to G6, H1 to H7, I1 to I7, and J1 to J7. The gradation value of a bright image is 255. In other areas, dark images are displayed. The gradation value of the dark image is 16. Regions A3 to 5, B3, B5, and C3 to 5 around the region B4 having a bright image are dark images. In this way, a region having a locally bright image with respect to the surrounding region is referred to as a partial high luminance region.

  The partial high-luminance area is not limited to an area that displays an image brighter than an image displayed in the surrounding area, such as the area B4. When the brightness of an image displayed in a certain area is higher than the brightness of an image displayed in at least one area around the area, it can be said that the area is a partial high brightness area. In the input image 10, regions G2 to G6, H1, and H7 are also partial high brightness regions.

  The representative luminance acquisition unit 61 acquires a representative luminance value for each area of the input image corresponding to each light emitting unit. In the first embodiment, the representative luminance value is the maximum value of the gradation values of the pixels in each area of the input image.

  FIG. 6 is a schematic diagram showing the representative luminance value of the corresponding input image area acquired by the representative luminance acquiring unit 61 for each light emitting unit of the backlight 8 in the first embodiment. In the first embodiment, since the luminance characteristic is the maximum value of the gradation value included in each region, the regions B4, G2 to G6, H1 to H7, I1 to I7, and J1 to J7 including a bright image are included. The luminance characteristic is 255. Similarly, the luminance characteristics of the areas A1 to A7, B1 to B3, B5 to B7, C1 to F7, G1 and G7 having only dark images are 16. The representative luminance acquisition unit 61 outputs the representative luminance value of the area of the input image corresponding to each acquired light emitting unit to the luminance value acquisition unit 62.

  The luminance value acquisition unit 62 acquires the light emission luminance value of the corresponding light emitting unit using the representative luminance value of the region of the input image corresponding to each light emitting unit. The luminance value acquisition unit 62 acquires luminance reference information that associates the representative luminance value with the light emitting unit from the memory 3. The luminance reference information is the LUT shown in FIG. The luminance value acquisition unit 62 acquires the emission luminance value of the corresponding light emitting unit using the representative luminance value of the area of the input image corresponding to each light emitting unit and the luminance reference information.

  FIG. 7 is a schematic diagram showing the light emission luminance values acquired by the luminance value acquisition unit 62 for each light emitting unit of the backlight 8 in the first embodiment. The light emission luminance values of the light emitting sections B4, G2 to G6, H1 to H7, I1 to I7, and J1 to J7 whose representative luminance value of the corresponding input image area is 255 are 50%. In addition, the light emission luminance values of the light emitting units A1 to A7, B1 to B3, B5 to B7, C1 to F7, G1, and G7 having a representative luminance value of 16 in the corresponding input image area are set to 13%. The luminance value acquisition unit 62 outputs the acquired emission luminance value for each light emitting unit to the HPF processing unit 63a.

  The HPF processing unit 63a executes HPF processing that emphasizes high-frequency components with respect to the emission luminance value, and outputs the HPF emission luminance value to the smoothing processing unit 63b. In the first embodiment, the HPF processing unit 63a performs a filter operation on the light emission luminance values of the light emitting units arranged in a 5 × 5 matrix with the target light emitting unit at the center, and the HPF light emission of the target light emitting unit. Get the luminance value. Expression 2 is an expression showing a filter calculation for obtaining the HPF light emission luminance value of the light emitting unit C3.

  BL_A1 to BL_E5 are light emission luminance values of the light emitting units A1 to E5 with the light emitting unit C3 as the center. Fh0 to Fh2 are horizontal filter coefficients. Fv0 to Fv2 are vertical filter coefficients. In the first embodiment, Fh0 = Fv0 = 1.2, Fh1 = Fv1 = −0.06, and Fh2 = Fv2 = −0.04. The calculation result of the filter operation can be adjusted in the number of digits by rounding off or rounding down according to the processing capability in each circuit module described later.

  Note that the number and range of the light emitting units adjacent to the target light emitting unit used for the filter calculation, and each coefficient can be arbitrarily set by the user or the designer. When the calculation result of the filter operation becomes a negative value, the HPF emission luminance value is set to 0.

  FIG. 8 is a schematic diagram showing HPF emission luminance values acquired by the HPF processing unit 63a for each light emitting unit of the backlight 8 in the first embodiment. The HPF processing unit 63a increases the light emission luminance value of the light emitting unit in which the light emission luminance value rapidly changes in the light emission luminance value distribution shown in FIG. When attention is paid to the light emitting part B4, the light emission luminance value 50 of the light emitting part B4 increases rapidly with respect to the light emission luminance value 13 of the adjacent light emitting part. Therefore, the HPF emission luminance value of the light emitting unit B4 is increased to 66 by the filter calculation. The HPF processing unit 63a outputs the HPF emission luminance value for each light emitting unit to the smoothing processing unit 63b.

  The smoothing processing unit 63b, when the HPF light emission luminance value of the light emitting unit of interest among the plurality of light emitting units is smaller than the HPF light emission luminance value of the adjacent light emitting unit adjacent to the light emitting unit of interest, the HPF light emission of the light emitting unit of interest. Increase brightness value. The smoothing processing unit 63b calculates the HPF light emission of the target light emitting unit by multiplying the largest value among the differences between the HPF light emission luminance value of the target light emitting unit and the HPF light emission luminance value of the adjacent light emitting unit by the smoothing coefficient. Add to luminance value. In the first embodiment, it is assumed that the smoothing coefficient is 0.3. The smoothing processing unit 63b performs processing using each light emitting unit as a target light emitting unit in order, and acquires a corrected light emission luminance value of each light emitting unit.

  Moreover, the smoothing process part 63b performs said smoothing process in multiple times. In the first embodiment, the smoothing processing unit 63b performs the smoothing process three times on each light emitting unit. By performing the smoothing process a plurality of times, the level difference between the light emitting portions of the HPF light emission luminance value becomes smoother. By smoothing the step of the HPF light emission luminance value between the light emitting units, there is an effect that the step of luminance of the image displayed on the display device 100 becomes inconspicuous.

  FIG. 9 shows a corrected emission luminance value obtained by performing smoothing processing on the HPF emission luminance value three times by the smoothing processing unit 63b for each emission unit of the backlight 8 in the first embodiment. It is the schematic diagram which showed. As a result of the smoothing process, the corrected emission luminance values of the light emitting units B1 to B7 change more smoothly between the light emitting units than the HPF emission luminance values of the light emitting units B1 to B7. In addition, the HPF light emission luminance value which has been equal to or lower than the light emission luminance value by the HPF processing becomes a value equal to or higher than the light emission luminance value.

  Note that the HPF light emission luminance value of the light emitting unit B4 corresponding to the region B4 which is a partial high luminance region is not greatly reduced by the smoothing process. Therefore, the effect of increasing the light emission luminance value of the light emitting unit B4 corresponding to the region B4 is maintained. The smoothing processing unit correction outputs a corrected light emission luminance value for each light emitting unit to the luminance determining unit 64.

  The luminance determination unit 64 determines the corrected light emission luminance value of each light emitting unit as a luminance setting value, and outputs it to the irradiation luminance estimation unit 51 and the light emission control unit 65. The light emission control unit 65 controls lighting of each light emitting unit of the backlight 8 based on the acquired luminance setting value.

  The above is the backlight control process in the display device 100. Part or all of the processing in each circuit module described above can be realized by the processor 2 executing a program read from the memory 3. In this case, the processor 2 executes each process in the order described above for each corresponding process.

  Hereinafter, the effect in the first embodiment will be described. FIG. 10 shows the irradiation of the display area of the liquid crystal panel 7 corresponding to the light emitting sections A4, B4, C4, D4, E4, F4, G4, H4, I4, and J4 (hereinafter A4 to J4) in the first embodiment. It is the schematic diagram which showed the luminance distribution of the light to be performed. In FIG. 10, the solid black line represents the irradiation luminance distribution of the display area corresponding to each light emitting unit when each light emitting unit is turned on based on the luminance setting value determined by the luminance determining unit 64 in the first embodiment. is there.

  In FIG. 10, a black broken line is a comparison showing an irradiation luminance distribution of a display area corresponding to each light emitting unit when each light emitting unit is turned on based on the light emitting luminance value determined from the representative luminance value shown in FIG. 7. It is an example. In FIG. 10, the thick line is the irradiation luminance necessary for the input image displayed in each display area to be displayed appropriately. In the first embodiment, when an image including a gradation value of 255 is displayed, it is assumed that an irradiation luminance of 1000 cd / m 2 is necessary. Accordingly, the display areas B4, G4, H4, I4, and J4 on which an input image including a bright image with a gradation value of 255 is displayed require an irradiation luminance of 1000 cd / m2.

  On the other hand, dark images having a gradation value of 16 are displayed in the display areas A4, C4, D4, E4, and F4. At this time, the gradation values of the images displayed in the display areas A4, C4, D4, E4, and F4 can be enlarged up to 16 times (255/16). Therefore, the required irradiation luminance is 1/16 (62.5 cd / m 2) of 1000 cd / m 2.

  First, a comparative example indicated by a black dotted line in FIG. 10 will be described. In the light emitting portions G4, H4, I4, and J4, the light is lit at the luminance setting value corresponding to the light emission luminance value of 50%. In the light emitting portions H4, I4, and J4, since the light diffused from the adjacent light emitting portions is incident, the reduction of the irradiation luminance to the display area due to the diffusion is small. Accordingly, the irradiation luminance of the display areas H4, I4, and J4 is 1000 cd / m2. Further, due to the influence of diffusion to the adjacent display area F4 and the like, the irradiation luminance of the display area G4 is 1000 cd / m 2 or less.

  The light emitting unit B4 is lit at a luminance setting value corresponding to the light emission luminance value of 50%, similarly to the light emitting units G4, H4, I4, and J4. However, since the light emission luminance value of the light emitting parts around the light emitting part B4 is low, it is impossible to receive the contribution of diffused light from the surrounding light emitting parts. Therefore, the irradiation brightness of the display area B4 is significantly smaller than the necessary 1000 cd / m 2.

  According to the first embodiment shown by the black solid line in FIG. 10, the light emitting units G4, H4, I4, and J4 are lit at the brightness setting value corresponding to the corrected light emission brightness value of 50 to 54%. Since light diffused from the adjacent light emitting units is incident on each of the light emitting units H4, I4, and J4, the irradiation luminance to the corresponding display area is 1000 cd / m 2 or more. In addition, since the luminance setting values of the light emitting unit G4 and the adjacent light emitting unit F4 are increased by the HPF process and the smoothing process, the irradiation luminance of the display region G4 is 1000 cd / m 2 or more. Accordingly, the display areas G4, H4, I4, and J4 are irradiated with light at an irradiation luminance necessary for displaying a bright image.

  Further, the light emitting section B2 facing the display area B2 is lit with a luminance setting value corresponding to the corrected light emission luminance value 66%. Further, the corrected light emission luminance value of the light emitting unit adjacent to the light emitting unit B2 is larger than the light emission luminance value acquired from the representative luminance value. Therefore, even if light diffused from the light emitting part B2 to the surroundings is taken into consideration, the irradiation luminance of the display region B2 is 1000 cd / m 2 or more. Furthermore, the smoothing process prevents the corrected light emission luminance value of the light emitting unit adjacent to the light emitting unit B2 from falling gently, thereby suppressing the luminance step in the display region displaying a dark image from being viewed as display unevenness. .

  As described above, according to the first embodiment, in the display device that displays the image by individually controlling the light emission luminance of the plurality of light emitting units, the light emission luminance value of the target light emitting unit and the light emission luminance value of the peripheral light emitting unit. The processing is performed so as to further increase the light emission luminance of the light emitting unit of interest in accordance with the difference. The light emission luminance value corresponds to the brightness of the image displayed in the display area corresponding to the light emitting unit. In other words, the display device according to the first embodiment has a partial high luminance according to the difference between the luminance of the partial high luminance region of the input image and the luminance of the image displayed in the peripheral region of the partial high luminance region. It can also be said that the process of increasing the light emission luminance of the light emitting unit corresponding to the area where the area is displayed is performed.

  Further, in the display device of the first embodiment, when the light emission luminance value of the target light emission unit is higher than the light emission luminance value of the peripheral light emission unit by a predetermined value or more, the light emission luminance of the light emission unit is higher than that when it is not. The light emission luminance may be controlled so as to increase. In other words, if the brightness of the partial high-brightness area of the input image is higher than the brightness of the image displayed in the area around the partial high-brightness area by a predetermined value or more, the partial high-brightness area It can also be said that the light emission luminance of the light emitting unit corresponding to the region where is displayed is increased. Here, the predetermined value can be arbitrarily designated by a user or a designer.

  That is, the display device according to the first embodiment increases the light emission luminance value of the target light emitting unit according to the difference between the light emission luminance value of the target light emitting unit and the light emission luminance value of the light emitting unit adjacent to the target light emitting unit. A process of obtaining the corrected light emission luminance value of the light emitting unit is executed to obtain the corrected light emission luminance value of each light emitting unit. Specifically, the display device of the first embodiment includes a light emitting unit adjacent to the target light emitting unit when the light emission luminance value of the target light emitting unit is larger than the light emission luminance value of the light emitting unit adjacent to the target light emitting unit. The light emission luminance value of the target light emitting unit is increased in accordance with the difference in the light emission luminance values of the two to obtain corrected light emission luminance of the target light emitting unit. Furthermore, in the display device of the first embodiment, when the light emission luminance value of the target light emitting unit is smaller than the light emission luminance value of the light emitting unit adjacent to the target light emitting unit, the light emission of the target light emitting unit and the adjacent light emitting unit. In accordance with the difference from the luminance value, the light emission luminance value of the target light emitting unit is increased to obtain the corrected light emission luminance of the target light emitting unit.

  Therefore, according to the display device described in the first embodiment, even when an image including a locally bright image is displayed, the necessary irradiation luminance can be provided and display can be suitably performed.

  Further, by smoothing the change in the light emission luminance by smoothing the luminance difference of the light emitting unit, it is possible to suppress display unevenness in the dark image region around the locally bright image region.

  In the first embodiment, correction processing is performed on the light emission luminance value of each light emitting unit determined according to the representative luminance value of the area of the input image corresponding to each light emitting unit, and the light emission luminance of each light emitting unit. However, the method of controlling the light emission luminance of each light emitting unit is not limited to this. It is also possible to perform the above-described correction processing on the representative luminance value of the region of the input image corresponding to each light emitting unit, and determine the light emitting luminance value of each light emitting unit based on the corrected representative luminance value. In this case, in the block diagram illustrated in FIG. 3, the luminance correction unit 63 is provided between the representative luminance acquisition unit 61 and the luminance value acquisition unit 62. Also, the reference luminance information that associates the corrected representative luminance value with the emission luminance value is determined so that the emission luminance value corresponds to the range that the corrected representative luminance value can take, unlike the above-described one. It is desirable to use the obtained reference luminance information.

  Specifically, when the feature amount of the attention area is larger than the feature amount of the adjacent area adjacent to the attention area among the plurality of areas of the input image, the HPF processing unit 63a determines the feature amount of the attention area. A process of increasing according to the difference between the feature value of the region and the feature value of the adjacent region is performed. Further, when the feature amount of the attention area is smaller than the feature amount of the adjacent area with respect to the feature amount acquired by the HPF processing section 63a, the smoothing processing section 63b converts the feature amount of the attention area into the feature amount of the attention area. A process of increasing according to the difference between the amount and the feature amount of the adjacent region is performed. The luminance value acquisition unit 62 acquires the luminance value of each light emitting unit based on the feature amount of the area corresponding to each light emitting unit processed by the smoothing processing unit 63b.

  By performing the above processing, when the brightness around the partial high-brightness area is lower than a predetermined level with respect to the brightness of the partial high-brightness area included in the image, the partial high-brightness area than when not The light emission luminance of the light emitting unit corresponding to the area where is displayed is increased. According to the display device according to the first embodiment, when displaying an image including a locally bright image (partial high luminance region), the necessary irradiation luminance is provided and the image is suitably displayed. Is possible.

(Second embodiment)
A second embodiment will be described using the display device 200. Since the device configuration of the display device 200 is the same as that of the display device 100, description thereof is omitted.

  FIG. 11 is a block diagram illustrating functional blocks of the display device 200 according to the second embodiment. FIG. 11 shows circuit modules provided in the display control unit 5 and the backlight control unit 6 of the display device 200, respectively. The display device 200 is different from the display device 100 in that the backlight control unit 6 includes a necessary luminance acquisition unit 66 and a luminance estimation unit 67.

  Of the functional blocks having the same names as those in the first embodiment, description of the circuit modules that perform the same functions as those in the first embodiment will be omitted.

  The necessary luminance acquisition unit 66 acquires irradiation luminance (required luminance) necessary for displaying an image in each area based on the representative luminance value of each area of the input image. The necessary luminance acquisition unit 66 acquires necessary luminance information that associates the representative luminance value with the necessary luminance from the memory 3. The required luminance acquisition unit 66 acquires the required luminance of the corresponding display area using the representative luminance value of each area and the required luminance information. The required luminance acquisition unit 66 outputs the required luminance of each display area to the luminance determination unit 64.

  The luminance estimation unit 67, when controlling the light emission luminance of each light emitting unit based on the corrected light emission luminance value acquired from the luminance correction unit 63, the luminance of light that is estimated to be irradiated to each display area (estimated luminance) To get. The luminance estimation unit 67 acquires diffusion information from the memory 3. The luminance estimation unit 67 acquires the estimated luminance using the diffusion information and the corrected light emission luminance value. The luminance estimation unit 67 outputs the estimated luminance to the luminance determination unit 64.

  The luminance determining unit 64 compares the required luminance of each display area with the estimated luminance, corrects the corrected light emission luminance value, and determines the luminance setting value for each light emitting unit. The luminance determination unit 64 determines a correction coefficient using the estimated luminance and the necessary luminance. The correction coefficient is a ratio between the required luminance and the estimated luminance in a display region where the difference between the required luminance and the estimated luminance is the largest among the display regions whose required luminance is smaller than the estimated luminance. The luminance determination unit 64 determines the luminance setting value by multiplying the correction light emission luminance value of each light emitting unit by the correction coefficient. The luminance determination unit 64 outputs the luminance setting value to the light emission control unit 65.

  Hereinafter, the backlight control process of the display device 200 in the second embodiment will be described in detail. Based on the input image input from the input interface 1, the representative luminance acquisition unit 61 acquires a representative luminance value of each region of the input image corresponding to each light emitting unit. Since the method for obtaining the representative luminance value is the same as that in the first embodiment, the description thereof is omitted. The representative luminance acquisition unit 61 outputs the representative luminance value of each light emitting unit to the luminance value acquisition unit 62 and the necessary luminance acquisition unit 66.

  The necessary luminance acquisition unit 66 acquires necessary luminance information from the memory 3. In the necessary luminance information, necessary luminance 1000 cd / m 2 is associated with the maximum value (255) that the representative luminance value can take. For the representative luminance value X (0 ≦ X <255), the necessary luminance is X / 255 × 1000 cd / m 2. The required brightness acquisition unit 66 acquires the required brightness of the corresponding display area from the required brightness information using the representative brightness value of each area of the input image. The necessary luminance acquisition unit 66 outputs the necessary luminance to the light emission luminance determining unit 26.

  The processing for acquiring the emission luminance value based on the representative luminance value acquired by the luminance value acquisition unit 62 and the processing for acquiring the HPF emission luminance value by the HPF processing unit 63a are the same as in the first embodiment, and therefore will be described. Is omitted.

  The smoothing processing unit 63b performs a smoothing process on the HPF light emission luminance value. In the second embodiment, the smoothing processing unit 63 executes the smoothing process with the smoothing coefficient set to 0.1. The smoothing process has the effect of suppressing the visibility of display unevenness by smoothing the light emission brightness between the light emitting parts, but it also supports areas that display dark images far from areas that contain bright images. In some cases, the light emission luminance of the light emitting unit to be increased is increased more than necessary. By reducing the smoothing coefficient, it is possible to suppress an increase in the light emission luminance value of the light emitting unit corresponding to a dark image away from a region including a bright image. The smoothing processing unit 63b outputs the corrected light emission luminance value to the luminance determination unit 64 and the luminance estimation unit 67.

  The luminance estimation unit 67 acquires the diffusion information from the memory 3, and acquires the estimated luminance of each display area when each light emitting unit emits light based on the corrected light emission luminance value. The luminance estimation unit 67 outputs the estimated luminance to the luminance determination unit 64.

  The luminance determination unit 64 further corrects the corrected light emission luminance value of the corresponding light emitting unit using the estimated luminance and the necessary luminance of each display area, and acquires a luminance value setting value. The luminance determination unit 64 uniformly corrects the corrected emission luminance value of each light emitting unit using the ratio between the estimated luminance and the necessary luminance of the display area where the difference between the estimated luminance and the necessary luminance is the largest, and the luminance value setting value And

  FIG. 12 is a schematic diagram showing the estimated luminance acquired by the luminance estimating unit 67 and the necessary luminance acquired by the necessary luminance acquiring unit 66 in the second embodiment with respect to the display areas A4 to J4. In FIG. 12, the solid black line is a distribution of the estimated luminance of each display area by the luminance estimation unit 67 in the second embodiment. In FIG. 12, the bold line represents the required luminance of each display area.

  In FIG. 12, the estimated brightness of the display area B4 and the display area G4 is smaller than the required brightness. The required luminance of the display area B4 and the display area G4 is both 1000 cd / m2. The estimated luminance of the display area B4 is 872 cd / m2. The estimated luminance of the display area G4 is 961 cd / m2. Therefore, the display area having the largest difference between the estimated brightness and the required brightness is the display area B4. The ratio between the estimated luminance of the display area B4 and the necessary luminance is 1.15 (= 1000/872). Therefore, the luminance determination unit 64 determines the correction coefficient as 1.15. The luminance determination unit 64 uniformly multiplies the correction light emission luminance value of each light emitting unit by the correction coefficient to obtain a luminance setting value. The luminance determination unit 64 outputs the luminance setting value of each light emitting unit to the light emission control unit 65.

  The light emission control unit 65 controls the light emission luminance of the backlight 8 based on the luminance setting value as in the first embodiment.

  Hereinafter, the effect of the second embodiment will be described. FIG. 13 is a schematic diagram showing the luminance of light applied to the display area of the liquid crystal panel 7 corresponding to the light emitting portions A4 to J4 in the second embodiment. In FIG. 13, the solid black line represents the distribution of irradiation luminance in the display area corresponding to each light emitting unit when each light emitting unit is turned on based on the luminance setting value determined by the luminance determining unit 64 in the second embodiment. is there.

  In FIG. 13, black dotted lines indicate the distribution of irradiation luminance of the display area corresponding to each light emitting unit when each light emitting unit is lit based on the luminance setting value determined by the luminance determining unit 64 in the first embodiment. Shown for comparison.

  According to the second embodiment, similarly to the first embodiment, it is possible to irradiate the display area B4 displaying a locally bright image with an irradiation luminance that satisfies the necessary luminance. Further, in the display areas A4, C4, and D4 that display a dark image around the display area B4, an increase in irradiation luminance with respect to the required luminance is suppressed.

  In the display areas A4, C4, and D4, dark images are displayed. When using a liquid crystal element whose transmittance increases as the voltage applied to the liquid crystal element of the liquid crystal panel 7 increases, a low voltage is applied to reduce the transmittance of the liquid crystal element in order to display a dark image. When the liquid crystal element is driven at a low voltage, the transmittance of the liquid crystal element may not be sufficiently reduced due to the characteristics of the liquid crystal element. When the luminance of light emitted from the backlight is high, an unintended amount of light may be transmitted to the front surface of the liquid crystal panel 7. This is visually recognized as so-called display unevenness or black floating in the display device. This phenomenon is easily noticeable in a dark image display area.

  According to the second embodiment, it is possible to suppress an increase in irradiation luminance with respect to necessary luminance in the display regions A4, C4, and D4 that display dark images around the display region B4. Therefore, while the irradiation luminance from the light emitting unit corresponding to the locally bright image is controlled to satisfy the required luminance, the irradiation luminance from the light emitting unit corresponding to the dark image around the bright image is the required luminance. Is prevented from becoming too large.

  According to the second embodiment, in a display device that displays an image by individually controlling the light emission luminances of a plurality of light emitting units, light emission is performed in a light emitting unit having a light emission luminance value larger than the light emission luminance values of surrounding light emitting units. Performs processing to increase brightness. Therefore, in the case of displaying an image including a locally bright partial high-luminance region, it is possible to provide necessary irradiation luminance and perform display appropriately.

  In addition, by smoothing the change in the light emission luminance by smoothing the luminance step of the light emitting unit, it is possible to suppress display unevenness in a dark image region around the partial high luminance region.

  Furthermore, when an image including a partial high-luminance area is displayed, it is possible to suppress black floating by suppressing the irradiation luminance of the display area corresponding to the dark area other than the bright area.

(Third embodiment)
A third embodiment will be described using the display device 300. The device configuration of the display device 300 is the same as that of the display device 100 shown in FIG. FIG. 14 is a block diagram illustrating functional blocks of the display device 300 according to the third embodiment. FIG. 14 shows circuit modules provided in the display control unit 5 and the backlight control unit 6 of the display device 300, respectively. The display device 300 is different from the display device 200 shown in FIG. 11 in the second embodiment in that the backlight control unit 6 includes a distribution characteristic acquisition unit 601 and a correction coefficient determination unit 602.

  Of the functional blocks having the same names as those of the second embodiment, the description of the circuit modules that perform the same functions as those of the second embodiment will be omitted.

  The distribution characteristic acquisition unit 601 acquires the luminance distribution characteristic based on the corrected light emission luminance value acquired from the luminance correction unit 63. The luminance distribution characteristics of the present embodiment mean the average value, the maximum value, and the minimum value of the corrected light emission luminance values. The distribution characteristic acquisition unit 601 outputs the luminance distribution characteristic to the correction coefficient determination unit 602.

  The correction coefficient determination unit 602 determines a luminance correction coefficient for correcting the magnitude of the luminance setting value based on the luminance distribution characteristic acquired from the distribution characteristic acquisition unit 601. Based on the luminance distribution characteristics, the correction coefficient determination unit 602 determines the magnitude of the variation based on whether or not the variation in the corrected light emission luminance value of each light emitting unit is equal to or greater than a threshold value (th1). Specifically, the correction coefficient determination unit 602 determines the variation in the corrected light emission luminance value when any of the difference between the maximum value and the average value of the corrected light emission luminance value and the difference between the minimum value and the average value is larger than the threshold th1. Is determined to be large. The correction coefficient determination unit 602 determines that the variation in the corrected light emission luminance value is small when the difference between the maximum value and the average value of the corrected light emission luminance value and the difference between the minimum value and the average value are both equal to or less than the threshold th1. I can say that. For example, it is assumed that the threshold th1 is 5.

  When the correction coefficient determination unit 602 determines that the variation in the corrected light emission luminance value is large, the correction coefficient determination unit 602 sets the value of the luminance correction coefficient as md1, and when the correction coefficient determination unit 602 determines that the variation in the correction light emission luminance value is small, it is smaller than md1. Let md2. The magnitude relationship between md1 and md2 is md1> md2. For example, it is assumed that md1 is 1.2 and md2 is 2.0.

  The luminance determination unit 64 determines a luminance setting value for each light emitting unit based on the necessary luminance, the estimated luminance, and the luminance correction coefficient. Similar to the second embodiment, the luminance determining unit 64 compares the required luminance with the estimated luminance and determines a correction coefficient. The luminance determining unit 64 determines the luminance setting value by multiplying the corrected light emission luminance value of each light emitting unit by the correction coefficient and the luminance correction coefficient. The luminance determination unit 64 outputs the luminance setting value to the irradiation luminance estimation unit 51 and the light emission control unit 65.

  Hereinafter, the backlight control process of the display device 300 in the third embodiment will be specifically described. Note that description of functional blocks that perform the same operations as those in the second embodiment is omitted.

  The distribution characteristic acquisition unit 601 acquires a luminance distribution characteristic based on the corrected light emission luminance value. Similar to the second embodiment, when the corrected emission luminance value is acquired based on the input image based on the image shown in FIG. 5, the luminance distribution characteristics are the average value 36, the maximum value 66, and the minimum value 12. When the input image is an image (all white image) having all pixel values of 255, the luminance distribution characteristics of this embodiment are an average value 50, a maximum value 50, and a minimum value 50.

  The correction coefficient determination unit 602 determines the presence or absence of variation based on the luminance distribution characteristics, and determines the luminance correction coefficient value. When the threshold th1 is 5, in the luminance distribution characteristic of the corrected emission luminance value determined based on the input image shown in FIG. 5, the difference between the maximum value and the average value of the corrected emission luminance value, and the corrected emission luminance value The difference between the minimum value and the average value is equal to or greater than the threshold th1. Therefore, the correction coefficient determination unit 602 determines that the variation in the corrected light emission luminance value determined based on the input image shown in FIG. 5 is large. In this case, the correction coefficient determination unit 602 sets the luminance correction coefficient value to md1 (1.2).

  When the input image is an all-white image, the difference between the maximum value and the average value of the corrected light emission luminance values and the difference between the minimum value and the average value of the corrected light emission luminance values are less than th1, so that the correction coefficient determination unit In step S602, it is determined that the variation in the corrected light emission luminance value determined based on the input image is small. In this case, the correction coefficient determination unit 602 sets the luminance correction coefficient value to md2 (1.0).

  The luminance determination unit 64 multiplies the corrected light emission luminance value of each light emitting unit by a correction coefficient obtained from the required luminance and the estimated luminance of each light emitting unit, and further uniformly sets the luminance correction coefficient value for each light emitting unit. Multiplication is performed to obtain the brightness setting value of each light emitting unit.

  The effects of the third embodiment will be described below. FIGS. 15 and 16 are schematic diagrams showing the luminance of light applied to the display area of the liquid crystal panel 7 corresponding to the light emitting portions A4 to J4 in the third embodiment. FIG. 15 is a schematic diagram showing the luminance of light applied to the display area of the liquid crystal panel 7 when the input image is an image including the partial high luminance area shown in FIG. The solid line in FIG. 15 shows the distribution of irradiation luminance in the display area corresponding to each light emitting unit when each light emitting unit is lit based on the luminance setting value determined by the luminance determining unit 64 in the third embodiment. The dotted lines in FIG. 15 indicate the distribution of irradiation luminance in the display area corresponding to each light emitting unit when each light emitting unit is turned on based on the luminance setting value determined by the luminance determining unit 64 in the second embodiment.

  As shown in FIG. 15, according to the third embodiment, similarly to the first and second embodiments, the display area B4 displaying a locally bright image is irradiated with light at an irradiation luminance that satisfies the necessary luminance. Irradiation is possible. Furthermore, the irradiation luminance is further increased by the luminance correction coefficient, so that the irradiation luminance of the area AP1 and the area AP2 corresponding to the end of the display area B4 satisfies the necessary luminance. Therefore, it becomes possible to irradiate light with a sufficient irradiation luminance with respect to the partial high-luminance region including the end of the region.

  FIG. 16 is a schematic diagram showing the luminance of light applied to the display area of the liquid crystal panel 7 when the input image is an all-white image. The solid line in FIG. 16 shows the distribution of irradiation luminance in the display area corresponding to each light emitting unit when each light emitting unit is turned on based on the luminance setting value determined by the luminance determining unit 64 in the third embodiment. The dotted line in FIG. 16 shows the distribution of irradiation luminance in the display area corresponding to each light emitting unit when each light emitting unit is turned on based on the luminance setting value determined by the luminance determining unit 64 in the second embodiment. Yes. When displaying an image that does not include a partial high-brightness region, variations in the corrected light emission luminance are reduced.

  According to the display device in the third embodiment, when an image that does not include a partial high-luminance region is displayed, the light emitted from each light-emitting unit is increased more than necessary in order to reduce the luminance correction coefficient. This can be reduced.

  Further, by determining a coefficient for further correcting the corrected luminance value according to the variation of the corrected luminance value, the coefficient is reduced with respect to the corrected luminance value determined based on the input image not including the partial high luminance area. It becomes possible to do. Therefore, it is possible to suppress an increase in power consumption of the light emitting unit due to the correction.

  In the third embodiment, the luminance correction coefficient is set to the same value for each light emitting unit, but may be partially changed. For example, the luminance correction values of the light emitting units corresponding to the outer peripheral display areas A1 to J1, J1 to J7, A7 to J7, and A1 to A7 with fewer adjacent light emitting units correspond to the other light emission corresponding to the inner region of the liquid crystal panel 7. It is also possible to set so as to be larger than the luminance correction value of the part. By setting the luminance correction value of the light emitting part at the outer peripheral part (outer side) where there are few adjacent light emitting parts larger than that of the inner light emitting part, light may always be emitted with irradiation luminance with a margin.

  Further, the distribution characteristic acquisition unit 601 of the third embodiment uses the average value, the maximum value, and the minimum value of the corrected light emission luminance as the luminance distribution characteristic, but other values may be used. For example, the total value or dispersion value of the corrected light emission luminance values may be used as the luminance distribution characteristic. For example, assume that the luminance distribution characteristics are total values. In this case, the correction coefficient determination unit 602 determines that the variation is small when the total value is equal to or greater than the predetermined value, and determines that the variation is large when the total value is less than the predetermined value.

  Further, the luminance distribution characteristic may be a dispersion value. In this case, the correction coefficient determination unit 602 determines that the variation is small when the variance value is equal to or smaller than the predetermined value, and determines that the variation is large when the variance value is larger than the predetermined value.

  In addition, the distribution characteristic acquisition unit 601 of the third embodiment acquires the luminance distribution characteristic based on the corrected light emission luminance value, but other values that can determine the variation of the luminance distribution may be used. For example, the representative luminance value (feature value) acquired by the representative luminance acquisition unit 61, the necessary luminance of the necessary luminance acquisition unit 66, the estimated luminance of the luminance estimation unit 67, and the luminance setting value of the luminance determination unit 64 are used. Also good.

  When the input image is a video signal such as 60 Hz or 120 Hz, the correction coefficient determination unit 602 may be provided with a cyclic filter in the time direction to suppress fluctuations in the luminance correction coefficient. This makes it possible to suppress fluctuations in irradiation luminance.

(Fourth embodiment)
A fourth embodiment will be described using the display device 400. Since the device configuration of the display device 400 is the same as that of the display device 100, description thereof is omitted. FIG. 17 is a block diagram illustrating functional blocks of the display device 400 according to the fourth embodiment. FIG. 17 shows circuit modules provided in the display control unit 5 and the backlight control unit 6 of the display device 100, respectively.

  The display device 400 differs from the display device 300 of the third embodiment shown in FIG. 14 in that the backlight control unit 6 includes an APL acquisition unit 603 instead of the distribution characteristic acquisition unit 601.

  Of the functional blocks having the same names as those in the third embodiment, description of the circuit modules that perform the same functions as those in the third embodiment will be omitted.

  The APL acquisition unit 603 acquires the average picture level (APL) of the input image and outputs the APL to the correction coefficient determination unit 602. In this embodiment, APL is the average gradation value of the image. Further, when the image specifies display brightness for each pixel, APL may be an average brightness value.

  The correction coefficient determination unit 602 determines a luminance correction coefficient for correcting the luminance setting value based on the APL acquired from the APL acquisition unit 603. The relationship between APL and the luminance correction coefficient is shown in FIG. As shown in FIG. 18, when the APL is equal to or less than the threshold th2, the luminance correction coefficient is set to md1, and when it is larger than the determination threshold th2, it gradually decreases from md1 toward 1. For example, it is assumed that the threshold th2 is 250.

  Hereinafter, the backlight control process of the display device 400 in the fourth embodiment will be specifically described. Description of functional blocks that perform the same operations as those in the third embodiment is omitted.

  The operation of the APL acquisition unit 603 will be described. When the input image is the image shown in FIG. 5, the APL acquired by the APL acquisition unit 603 is 108. When the input image is an all-white image, APL is 255.

  The operation of the correction coefficient determination unit 602 will be described. When the image shown in FIG. 5 is input, since APL is 108, it is less than th2 (250). Therefore, the correction coefficient determination unit 602 sets the luminance correction coefficient value to md1. When an all-white image is input, since the APL is 255, the determination threshold th2 = 250 or more. In this case, the luminance correction coefficient value is 1.0 as shown in FIG.

  Similarly to the third embodiment, the luminance determining unit 64 determines the luminance setting value for each light emitting unit based on the necessary luminance, the estimated luminance, and the luminance correction coefficient. Since the following operations are the same as those in the third embodiment, description thereof is omitted.

  As described above, according to the fourth embodiment, similarly to the first to third embodiments, it is possible to irradiate light with an irradiation luminance that satisfies a necessary luminance with respect to a display region that displays a locally bright image. It becomes possible. Further, by further increasing the irradiation luminance by using the luminance correction coefficient, it becomes possible to irradiate light at an irradiation luminance having a margin with respect to the necessary luminance at the end portion of the display area where a locally bright image is displayed.

  In addition, when displaying an image that does not include a partial high-brightness region, it is possible to reduce excessively irradiating light in order to reduce the brightness correction coefficient.

  In the fourth embodiment, as in the third embodiment, the luminance correction value of the light emitting unit corresponding to the outer display area with few adjacent light emitting units is set to md2 = 1.2, so that there is always a margin. You may irradiate light with the irradiation brightness.

(Other embodiments)
The present invention is also realized by executing the following processing. In other words, this is a process in which software that implements the functions of the above-described embodiments is supplied to a system or apparatus via a network or various recording media, and a computer of the system or apparatus reads and executes the program code. Here, the software includes a program. The computer may be an arithmetic processing device such as a CPU or MPU. In this case, the program and a recording medium readable by the computer of the system or apparatus storing the program constitute the present invention.

DESCRIPTION OF SYMBOLS 100 Display apparatus 7 Liquid crystal panel 8 Backlight 61 Representative brightness | luminance acquisition part 62 Brightness value acquisition part 63 Brightness correction part 63a HPF process part 63b Smoothing process part 65 Light emission control part

Claims (30)

A plurality of light emitting means for irradiating light;
Display means for transmitting the irradiated light based on the input image and displaying the image on the screen;
First acquisition means for acquiring a first luminance value of each light emitting means based on the luminance of the region of the input image corresponding to each light emitting means;
Among the plurality of light emitting means, when the first luminance value of the first attention light emitting means is larger than the first luminance value of the first adjacent light emitting means adjacent to the first attention light emitting means, Increasing the first luminance value of the first attention light emitting means according to the difference between the first luminance value of the first attention light emitting means and the first luminance value of the first adjacent light emitting means; First processing means for obtaining second luminance values of the plurality of light emitting means;
Among the plurality of light emitting means, when the second luminance value of the second attention light emitting means is smaller than the second luminance value of the second adjacent light emitting means adjacent to the second attention light emitting means, Increasing the second luminance value of the second attention light emitting means according to the difference between the second luminance value of the second attention light emitting means and the second luminance value of the second adjacent light emitting means; Second processing means for obtaining third luminance values of the plurality of light emitting means;
Control means for controlling light emission of each light emitting means using the third luminance value of each light emitting means;
A display device comprising:   The first processing means performs a filter operation that emphasizes a high-frequency component on the distribution of the first luminance values of the plurality of light emitting means, and obtains the second luminance value of each light emitting means. The display device according to claim 1.   The first processing unit adds a value obtained by multiplying the first luminance value of the first adjacent light emitting unit by a predetermined coefficient to the first luminance value of the first target light emitting unit, and The display device according to claim 1, wherein a second luminance value of one attention light emitting unit is acquired.   The said 1st process means does not perform the process which estimates the irradiation brightness | luminance irradiated to the said display means when each light emission means light-emits with the said 1st brightness | luminance value, The Claim 1 thru | or 3 characterized by the above-mentioned. The display device according to any one of the above.   The second processing means includes a second brightness value that is the highest among the second brightness values of the plurality of second adjacent light emitting means adjacent to the second noticed light emitting means, and the second noticed light emitting means. The third luminance value of the second noticed light emitting means is acquired by increasing the second brightness value of the second noticeable light emitting means according to a difference from the second brightness value. The display device according to any one of claims 1 to 4. Third acquisition means for acquiring a necessary luminance required for displaying the input image;
First estimating means for obtaining estimated brightness irradiated to the display means when the plurality of light emitting means are irradiated with light at the third brightness value;
A first correction unit that compares the estimated luminance with the required luminance, and performs correction to increase the third luminance value of the light emitting unit corresponding to a region where the estimated luminance is smaller than the required luminance;
The display device according to claim 1, further comprising:   The first acquisition unit is based on at least one of a maximum gradation value, an average gradation value, a maximum luminance, and an average luminance of the input image displayed in the area of the screen corresponding to each of the plurality of light emitting units. The display device according to claim 1, wherein the first luminance value of each light emitting unit is acquired. Second acquisition means for acquiring variations in the third luminance values of the plurality of light emitting means based on the input image;
Second variation means for relatively increasing the third luminance value when the variation of the third luminance value is large compared to the case where the third luminance value is not;
The display device according to claim 1, further comprising:   The second acquisition unit is configured to generate the third luminance based on at least one of a feature amount indicating the luminance of the region of the input image corresponding to each light emitting unit, the necessary luminance, the estimated luminance, and the third luminance value. The display device according to claim 8, wherein variation in values is acquired.   The second correction means includes a feature value indicating the brightness of the area of the input image corresponding to each light emitting means, the required brightness, the estimated brightness, and a maximum value and an average value of at least one of the third brightness values. 10. The display according to claim 9, wherein when either the difference or the difference between the minimum value and the average value is larger than the first threshold value, the third luminance value is relatively increased as compared with the case where it is not. apparatus.   The second correction means has at least one variance value of a feature value indicating the brightness of the area of the input image corresponding to each light emitting means, the required brightness, the estimated brightness, and the third brightness value as a second threshold value. 10. The display device according to claim 9, wherein the third luminance value is relatively increased when larger than that when not larger.   The second correction means has a third threshold value, wherein a total value of at least one of a feature quantity indicating the brightness of the area of the input image corresponding to each light emitting means, the required brightness, the estimated brightness, and the third brightness value is 10. The display device according to claim 9, wherein the third luminance value is relatively increased when smaller than that when the smaller luminance is not.   The said 2nd correction | amendment means raises the said 3rd light emission luminance value corresponding to the light source of the outer side of these light emission means relatively, The any one of Claims 8 thru | or 12 characterized by the above-mentioned. Display device. Third acquisition means for acquiring an APL of the input image;
Third correction means for relatively increasing the third luminance value when the APL is lower than a fourth threshold than when the APL is not;
The display device according to claim 1, further comprising:   The display device according to claim 1, wherein the display unit is a liquid crystal panel. A plurality of light emitting means for irradiating light;
Display means for transmitting the irradiated light based on the input image and displaying the image on the screen;
First acquisition means for acquiring a first feature amount indicating luminance of a plurality of regions of the input image corresponding to the plurality of light emission means;
When the first feature amount of the first attention region among the plurality of regions is larger than the first feature amount of the first adjacent region adjacent to the first attention region, the first attention amount The first feature amount of the region is increased according to a difference between the first feature amount of the first region of interest and the first feature amount of the first adjacent region, and the second feature amount of the plurality of regions is increased. First processing means for acquiring feature quantities;
When the second feature amount of the second attention region is smaller than the second feature amount of the second adjacent region adjacent to the second attention region among the plurality of regions, the second attention amount The second feature amount of the region is increased according to a difference between the second feature amount of the second attention region and the second feature amount of the second adjacent region, and the third feature amount of the plurality of regions is increased. A second processing means for acquiring a feature amount;
Control means for controlling the light emission of the corresponding light emitting means based on the third feature amount of each light emitting means;
A display device comprising: A plurality of light emitting means for irradiating light;
Display means for transmitting the irradiated light based on the input image and displaying the image on the screen;
First acquisition means for acquiring a first luminance value of each light emitting means based on the luminance of the region of the input image corresponding to each light emitting means;
Of the plurality of light emitting means, the first brightness of the noticeable light emitting means is determined according to a difference between the first brightness value of the noticeable light emitting means and the first brightness value of the adjacent light emitting means adjacent to the noticeable light emitting means. Control means for controlling the light emission of the plurality of light emitting means based on the second luminance values of the plurality of light emitting means having increased values;
A display device comprising: The control means includes
When the first luminance value of the target light emitting unit is greater than the first luminance value of the adjacent light emitting unit, the first luminance value of the target light emitting unit and the first luminance value of the adjacent light emitting unit are According to the difference, the first luminance value of the noticeable light emitting means is increased to be the second luminance value of the noticeable light emitting means,
When the first luminance value of the attention light emitting unit is smaller than the first luminance value of the adjacent light emitting unit, the first luminance value of the attention light emitting unit and the first luminance value of the adjacent light emitting unit are 18. The display device according to claim 17, wherein the first luminance value of the attention light emitting unit is increased according to the difference to obtain the second luminance value of the attention light emission unit. A plurality of light emitting means for irradiating light;
Display means for transmitting the irradiated light based on the input image and displaying the image on the screen;
First acquisition means for acquiring a first feature amount indicating luminance of a plurality of regions of the input image corresponding to the plurality of light emission means;
The first luminance value of the attention area is increased according to a difference between the first feature amount of the attention area and the first feature amount of the adjacent area adjacent to the attention area among the plurality of areas. Control means for controlling the light emission of the plurality of light emitting means at the light emission luminance of the plurality of light emitting means based on the second feature amount of the plurality of regions;
A display device comprising: A display device control method comprising: a plurality of light emitting means for irradiating light; and a display means for transmitting light emitted based on an input image and displaying an image on a screen.
A first acquisition step of acquiring a first luminance value of each light emitting means based on the luminance of the region of the input image corresponding to each light emitting means;
Among the plurality of light emitting means, when the first luminance value of the first attention light emitting means is larger than the first luminance value of the first adjacent light emitting means adjacent to the first attention light emitting means, Increasing the first luminance value of the first attention light emitting means according to the difference between the first luminance value of the first attention light emitting means and the first luminance value of the first adjacent light emitting means; A first processing step of obtaining second luminance values of the plurality of light emitting means;
Among the plurality of light emitting means, when the second luminance value of the second attention light emitting means is smaller than the second luminance value of the second adjacent light emitting means adjacent to the second attention light emitting means, Increasing the second luminance value of the second attention light emitting means according to the difference between the second luminance value of the second attention light emitting means and the second luminance value of the second adjacent light emitting means; A second processing step of obtaining a third luminance value of the plurality of light emitting means;
A control step of controlling light emission of each light emitting means using the third luminance value of each light emitting means;
A control method for a display device, comprising:   In the first processing step, a filter operation that emphasizes a high-frequency component is performed on the distribution of the first luminance values of the plurality of light emitting units to obtain the second luminance value of each light emitting unit. 21. The method for controlling a display device according to claim 20,   In the first processing step, a value obtained by multiplying the first luminance value of the first light emitting unit by a predetermined coefficient is added to the first luminance value of the first attention light emitting unit. The method for controlling a display device according to claim 20 or 21, wherein a second luminance value of one attention light emitting means is acquired.   23. The process according to claim 20, wherein the first processing step does not execute a process of estimating an irradiation luminance applied to the display unit when each light emitting unit emits light with the first luminance value. The control method of the display apparatus of any one.   In the second processing step, the highest second luminance value among the second luminance values of the plurality of second adjacent light emitting units adjacent to the second target light emitting unit, and the second target light emitting unit The third luminance value of the second noticed light emitting means is acquired by increasing the second brightness value of the second noticeable light emitting means according to a difference from the second brightness value. 24. The method for controlling a display device according to any one of items 20 to 23. A display device control method comprising: a plurality of light emitting means for irradiating light; and a display means for transmitting light emitted based on an input image and displaying an image on a screen.
A first acquisition step of acquiring a first feature amount indicating luminance of a plurality of regions of the input image corresponding to the plurality of light emitting means;
When the first feature amount of the first attention region among the plurality of regions is larger than the first feature amount of the first adjacent region adjacent to the first attention region, the first attention amount The first feature amount of the region is increased according to a difference between the first feature amount of the first region of interest and the first feature amount of the first adjacent region, and the second feature amount of the plurality of regions is increased. A first processing step for acquiring a feature amount;
When the second feature amount of the second attention region is smaller than the second feature amount of the second adjacent region adjacent to the second attention region among the plurality of regions, the second attention amount The second feature amount of the region is increased according to a difference between the second feature amount of the second attention region and the second feature amount of the second adjacent region, and the third feature amount of the plurality of regions is increased. A second processing step for acquiring a feature amount;
A control step of controlling light emission of the corresponding light emitting means based on the third feature amount of each light emitting means;
A control method for a display device, comprising: A display device control method comprising: a plurality of light emitting means for irradiating light; and a display means for transmitting light emitted based on an input image and displaying an image on a screen.
A first acquisition step of acquiring a first luminance value of each light emitting means based on the luminance of the region of the input image corresponding to each light emitting means;
Of the plurality of light emitting means, the first brightness of the noticeable light emitting means is determined according to a difference between the first brightness value of the noticeable light emitting means and the first brightness value of the adjacent light emitting means adjacent to the noticeable light emitting means. A control step of controlling the light emission of the plurality of light emitting means based on the second luminance values of the plurality of light emitting means having increased values;
A control method for a display device, comprising: The control step includes
When the first luminance value of the target light emitting unit is greater than the first luminance value of the adjacent light emitting unit, the first luminance value of the target light emitting unit and the first luminance value of the adjacent light emitting unit are According to the difference, the first luminance value of the noticeable light emitting means is increased to be the second luminance value of the noticeable light emitting means,
When the first luminance value of the attention light emitting unit is smaller than the first luminance value of the adjacent light emitting unit, the first luminance value of the attention light emitting unit and the first luminance value of the adjacent light emitting unit are 27. The method of controlling a display device according to claim 26, wherein the first luminance value of the noticeable light emitting means is increased according to the difference to obtain the second luminance value of the noticeable light emitting means. A display device control method comprising: a plurality of light emitting means for irradiating light; and a display means for transmitting light emitted based on an input image and displaying an image on a screen.
A first acquisition step of acquiring a first feature amount indicating brightness of a plurality of regions of the input image corresponding to the plurality of light emitting means;
The first luminance value of the attention area is increased according to a difference between the first feature amount of the attention area and the first feature amount of the adjacent area adjacent to the attention area among the plurality of areas. A control step of controlling light emission of the plurality of light emitting means with light emission luminance of the plurality of light emitting means based on the second feature amount of the plurality of regions;
A control method for a display device, comprising:   A program that causes a computer to execute each step of the control method for a display device according to any one of claims 20 to 28.   A storage medium storing the program according to claim 29 and readable by an arithmetic processing unit.

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