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EP-4312207-B1 - CIRCUIT DEVICE AND DISPLAY SYSTEM

EP4312207B1EP 4312207 B1EP4312207 B1EP 4312207B1EP-4312207-B1

Inventors

  • NAKAHARA, TATSUNORI

Dates

Publication Date
20260506
Application Date
20230721

Claims (8)

  1. A circuit device (100) comprising: a storage unit (170) configured to store a plurality of lookup tables each indicating an attenuation rate distribution of a light source element of a backlight (210) of a display device (200) including a display panel (220) and the backlight (210); and a luminance information calculation circuit (150) configured to calculate luminance information indicating a luminance of light reaching a target pixel (20) of the display panel from the backlight, wherein the storage unit is configured to store, as the plurality of lookup tables, a first lookup table that is associated with a first light source element (10) provided at a first position of the backlight and that indicates a first attenuation rate distribution of the first light source element, and a second lookup table that is associated with a second light source element (10) provided at a second position different from the first position of the backlight and that indicates a second attenuation rate distribution of the second light source element, the luminance information calculation circuit (150) is configured to obtain a first attenuation rate of light reaching the target pixel (20) from the first light source element based on the first lookup table, obtain a second attenuation rate of light reaching the target pixel from the second light source element based on the second lookup table, and calculate the luminance information based on the first attenuation rate and the second attenuation rate, the second position is a position that is closer to a first side (EDA) of the display panel than is the first position, the backlight includes a third light source element provided at a third position that is closer to a third side (EDC) facing the first side of the display panel than is the first position, and the luminance information calculation circuit is configured to calculate a third attenuation rate of light reaching the target pixel from the third light source element based on a lookup table obtained by rotating the second lookup table by 180°, and calculate the luminance information based on the first attenuation rate, the second attenuation rate, and the third attenuation rate.
  2. A circuit device (100) comprising: a storage unit (170) configured to store a plurality of lookup tables each indicating an attenuation rate distribution of a light source element of a backlight (210) of a display device (200) including a display panel (220) and the backlight (210); and a luminance information calculation circuit (150) configured to calculate luminance information indicating a luminance of light reaching a target pixel (20) of the display panel from the backlight, wherein the storage unit is configured to store, as the plurality of lookup tables, a first lookup table that is associated with a first light source element provided at a first position of the backlight and that indicates a first attenuation rate distribution of the first light source element, and a second lookup table that is associated with a second light source element provided at a second position different from the first position of the backlight and that indicates a second attenuation rate distribution of the second light source element, the luminance information calculation circuit (150) is configured to obtain a first attenuation rate of light reaching the target pixel (20) from the first light source element based on the first lookup table, obtain a second attenuation rate of light reaching the target pixel from the second light source element based on the second lookup table, and calculate the luminance information based on the first attenuation rate and the second attenuation rate, the second position is a position that is closer to a first corner portion (CNA), at which a first side (EDA) and a second side (EDB) of the display panel intersect with each other, than is the first position, and the backlight includes a third light source element provided at a third position that is closer to a second corner portion (CNC), at which a third side (EDC) facing the first side (EDA) of the display panel and a fourth side (EDD) facing the second side (EDB) of the display panel intersect with each other, than is the first position, and the luminance information calculation circuit is configured to calculate a third attenuation rate of light reaching the target pixel from the third light source element based on a lookup table obtained by rotating the second lookup table by 180°, and calculate the luminance information based on the first attenuation rate, the second attenuation rate, and the third attenuation rate.
  3. The circuit device according to claim 1 or claim 2, wherein each of the lookup tables is a table in which an attenuation rate at a distance, from a light source element to a pixel of the display panel, is associated with the distance, and the luminance information calculation circuit (150) is configured to obtain the first attenuation rate at a distance from the first light source element to the target pixel based on the first lookup table, and obtain the second attenuation rate at a distance from the second light source element to the target pixel based on the second lookup table.
  4. The circuit device according to claim 1 or claim 2, wherein the first attenuation rate distribution is an attenuation rate distribution rotationally symmetric with respect to a center thereof, and the second attenuation rate distribution is an attenuation rate distribution non-rotationally symmetric with respect to a center thereof.
  5. The circuit device according to claim 4, wherein in the second attenuation rate distribution, an attenuation characteristic in a direction from the center toward one side of the display panel and an attenuation characteristic in a direction from the center toward a side different from the one side of the display panel are different from each other.
  6. The circuit device according to claim 1 or claim 2, wherein the storage unit stores, as the plurality of lookup tables, a third lookup table that is associated with a third light source element provided at a third position different from the first position and the second position of the backlight and that indicates a third attenuation rate distribution of the third light source element, the second position is a position that is closer to a first side of the display panel than is the first position, the third position is a position that is closer to a first corner portion, at which a second side and a third side of the display panel intersect with each other, than is the first position, and the luminance information calculation circuit is configured to obtain a third attenuation rate of light reaching the target pixel from the third light source element based on the third lookup table, and calculate the luminance information based on the first attenuation rate, the second attenuation rate, and the third attenuation rate.
  7. The circuit device according to claim 1 or claim 2, further comprising: a luminance analysis circuit (140); and a color correction circuit (160), wherein the luminance analysis circuit is configured to perform luminance analysis on image data and obtain dimming information in local dimming control of the backlight based (210) on a result of the luminance analysis, the luminance information calculation circuit (150) is configured to obtain a first luminance of the light reaching the target pixel from the first light source element based on the dimming information and the first attenuation rate, obtain a second luminance of the light reaching the target pixel from the second light source element based on the dimming information and the second attenuation rate, and calculate the luminance information based on the first luminance and the second luminance, the color correction circuit (160) is configured to perform color correction on image data of the target pixel (20) based on the luminance information, and output image data (IMB) after the color correction to the display device (200).
  8. A display system (500) comprising: the circuit device (100) according to claim 1 or claim 2; and the display device (200).

Description

BACKGROUND 1. Technical Field The present disclosure relates to a circuit device, a display system, and the like. 2. Related Art JP-A-2019-095559 discloses an image display device that performs local dimming. The image display device includes an LED output value calculation unit, a display luminance data calculation unit, and an LDC data calculation unit. The LED output value calculation unit obtains emission luminance data indicating a luminance during light emission of a light source corresponding to each area of an image. The display luminance data calculation unit obtains diffusion luminance data by performing convolution processing using a previously prepared luminance diffusion function on the emission luminance data. A linear interpolation unit performs linear interpolation processing on the diffusion luminance data to obtain display luminance data which is data having a value for each pixel for each primary color. The LDC data calculation unit obtains a light transmittance of each pixel for each primary color based on input image data and the display luminance data, and outputs, as LCD data, data representing the light transmittance. Since a plurality of light sources are arranged in a backlight and peripheral structures of the light sources are different according to positions of the light sources, diffusion patterns of light reaching a display panel from the light sources differ depending on a difference in the peripheral structures. When a luminance of the light reaching each pixel of the display panel from the backlight is obtained without considering such a difference in the diffusion patterns, there is a problem that the luminance cannot be obtained with high accuracy. Since color correction of image data is performed based on the luminance of the light reaching each pixel, when the luminance cannot be obtained with high accuracy, appropriate color correction cannot be performed. JP-A-2019-095559 neither discloses nor suggests to consider a difference in the diffusion patterns of the light according to the positions of the light sources when the luminance of the light reaching each pixel from the backlight is obtained. US 2021/311361 discloses a display device including a backlight luminance distribution calculation unit configured to calculate an intensity of illumination light from a backlight in a pixel of interest. The backlight luminance distribution calculation unit calculates the intensity of illumination light with reference to a one-dimensional lookup table indicating a relationship between a distance from one of control areas included in the backlight to the pixel of interest and the intensity of illumination light at the distance. US 2015/279286 discloses a display device in which pixels each including first to fourth subpixels that respectively display first to third primary colors and fourth color are arranged on an image display panel. A control unit calculates a required luminance value for each block of the display surface of the panel based on an input image signal, determines a light source lighting amount of the lighting unit based on luminance distribution information on the lighting unit so as to satisfy the required luminance value, generates luminance information on each pixel based on the luminance distribution information and light source lighting amount, generates an output image signal that drives the subpixels based on the luminance information and input image signal, controls the lighting unit by the light source lighting amount, and controls the panel by the output image signal. US 2015/062486 discloses a display device that includes: a transmission-type display member having a display area that is sequentially scanned; and an illumination member that is arranged on a rear face of the display member and includes a plurality of illumination units that are arranged so as to be aligned in a direction from one end portion side toward the other end portion side along a direction in which the display area is sequentially scanned. The illumination unit is in a light emitting state over a predetermined light emitting period after sequential scanning of display units formed from a portion of the display area, which corresponds to the illumination unit, is completed, and the illumination units are sequentially scanned from one end portion side to the other end portion side in accordance with the sequential scanning of the display area. SUMMARY Aspects of the present disclosure relate to a circuit device as set out in appended independent claims 1 and 2. Preferred features of these circuit devices are set out in the dependent claims. Another aspect of the present disclosure relates to a display system including the circuit device and the display device. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration example of an electronic device including a display system according to an embodiment.FIG. 2 is a detailed configuration example of a circuit device.FIG. 3 is a flow