Local dimming for panel display devices using two-dimensional light source array

Abstract

To enable implementation of local dimming that can achieve high dynamic contrast and low power consumption.SOLUTION: A display device includes: a driver circuit; and a backlight control circuit. The backlight device includes an array of light sources configured to illuminate a display area of a display panel. The display area is segmented into a plurality of zones corresponding to the light sources, respectively. The plurality of zones includes: inner zones; and outermost peripheral zones. Inner light sources of the light source array are each located in a center of a corresponding zone of the inner zones. Each outermost peripheral zone is different in shape from at least one inner zone adjacent to at least one outermost peripheral zone. The backlight control circuit is configured to control a luminance level of a first outermost peripheral light source of the light source on the basis of pixel data on a pixel in a first outermost peripheral zone of the outermost peripheral zones. The first outermost peripheral light source corresponds to the first outermost peripheral zone.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present disclosure relates generally to panel displays, and more particularly to local dimming for panel displays that use two-dimensional light source arrays. [Background technology]

[0002] A panel display device including a light-transmitting display panel (e.g., a light-transmitting liquid crystal display (LCD) panel) may incorporate a backlight device that illuminates the light-transmitting display panel. Modern backlight devices, such as direct backlights and full-array backlights, may be configured to illuminate the display panel with a two-dimensional (2D) array of light sources (e.g., light-emitting diodes (LEDs)). The use of a 2D light source array in a backlight device enables the implementation of local dimming, which can achieve high dynamic contrast and low power consumption by individually controlling each light source (e.g., light-emitting diode (LED)) in the 2D light source array according to input image data. Summary of the Invention

[0003] This Summary is provided to introduce a selection of concepts in a concise form that are further described below. It is not intended to necessarily identify key features or essential features of the present disclosure. The present disclosure may include various aspects and embodiments described below.

[0004] In an exemplary embodiment, the present disclosure provides a display device. The display device includes a backlight device, a driver circuit, and a backlight control circuit. The backlight device includes an array of light sources configured to illuminate a display area of ​​a display panel. The display area is divided into a plurality of zones, each corresponding to a light source. The plurality of zones includes an inner zone and an outermost zone. The inner zone corresponds to an internal light source of the array of light sources and is located away from an edge of the display area of ​​the display panel. Each internal light source is located at the center of each inner zone. The outermost zone is located along the edge of the display area of ​​the display panel and corresponds to an outermost light source of the array of light sources. Each outermost zone has a different size or shape from at least one inner zone adjacent to at least one outermost zone. The driver circuit is configured to drive a plurality of pixels in the display area. The backlight control circuit is configured to control a brightness level of a first outermost light source of the array of light sources based on first pixel data of a first pixel of the plurality of pixels. Here, the first pixel is located in a first outermost zone of the outermost zones, and the first outermost light source corresponds to the first outermost zone.

[0005] In another exemplary embodiment, the present disclosure provides a display driver including a driver circuit and a backlight control circuit. The driver circuit is configured to drive a plurality of pixels located in a display area of ​​a display panel. The display area is illuminated by a backlight device including an array of light sources. The display area is divided into a plurality of zones corresponding to the light sources, respectively. The plurality of zones includes an inner zone and an outermost zone. The inner zones correspond to internal light sources of the array of light sources and are located away from the edges of the display area of ​​the display panel. Each of the internal light sources is located at the center of each inner zone. The outermost zones are located along the edges of the display area of ​​the display panel and correspond to the outermost light sources of the array of light sources. Each of the outermost zones has a different size or shape from at least one inner zone adjacent to at least one of the outermost zones. The backlight control circuit is configured to control a brightness level of a first outermost light source of the array of light sources based on first pixel data of a first pixel of the plurality of pixels. The first pixel is located in the first outermost zone of the outermost zones, and the first outermost light source corresponds to the first outermost zone.

[0006] In yet another exemplary embodiment, the present disclosure provides a method for local dimming. The method includes illuminating a display area of ​​a display panel with a backlight device including an array of light sources. The display area is divided into a plurality of zones, each corresponding to a light source. The plurality of zones includes an inner zone and an outermost zone. The inner zones correspond to internal light sources of the array of light sources and are located away from the edges of the display area of ​​the display panel. Each of the internal light sources is located at the center of each inner zone. The outermost zones are located along the edges of the display area of ​​the display panel and correspond to the outermost light sources of the array of light sources. Each of the outermost zones has a different size or shape than at least one inner zone adjacent to at least one of the outermost zones. The method further includes driving a plurality of pixels in the display area. The method further includes controlling a brightness level of a first outermost light source of the array of light sources based on first pixel data of a first pixel of the plurality of pixels. The first pixel is located in a first outermost zone of the outermost zones, and the first outermost light source corresponds to the first outermost zone.

[0007] Other features and aspects are described in more detail below with reference to the accompanying drawings. [Brief explanation of the drawings]

[0008] [Figure 1A] FIG. 1A illustrates an example configuration of a display device that supports local dimming, according to one or more examples of the present disclosure.

[0009] [Figure 1B] FIG. 1B illustrates an example arrangement of zones of a display panel and light sources illuminating the display panel, according to one or more examples of the present disclosure.

[0010] [Figure 2] FIG. 2 illustrates example filter coefficients used to control the brightness level of a light source, according to one or more examples of this disclosure.

[0011] [Figure 3A]FIG. 3A illustrates an example configuration of a display device according to one or more examples of the present disclosure.

[0012] [Figure 3B] FIG. 3B is a close-up view of an example arrangement of zones and light sources, according to one or more examples of the present disclosure.

[0013] [Figure 4A] FIG. 4A illustrates an example of zone definitions for a display panel, according to one or more embodiments.

[0014] [Figure 4B] FIG. 4B illustrates example filter coefficients used to control the brightness level of a light source, according to one or more embodiments.

[0015] [Figure 5] FIG. 5 illustrates an example display device configuration according to one or more embodiments.

[0016] [Figure 6] FIG. 6 illustrates an example arrangement of light sources in a backlight unit and an example definition of zones for a display panel, according to one or more embodiments.

[0017] [Figure 7A] FIG. 7A illustrates a close-up view of the top left corner of the display area in accordance with one or more embodiments.

[0018] [Figure 7B] FIG. 7B illustrates a close-up view of the top right corner of the display area in accordance with one or more embodiments.

[0019] [Figure 7C] FIG. 7C illustrates a close-up view of the bottom left corner of the display area in accordance with one or more embodiments.

[0020] [Figure 7D] FIG. 7D illustrates a close-up view of the bottom right corner of the display area in accordance with one or more embodiments.

[0021] [Figure 8] FIG. 8 illustrates an example display driver configuration according to one or more embodiments.

[0022] [Figure 9] FIG. 9 illustrates an example configuration of an image analysis circuit according to one or more embodiments.

[0023] [Figure 10] FIG. 10 illustrates an example of a filter coefficient definition according to one or more embodiments.

[0024] [Figure 11A] FIG. 11A illustrates an example of defining filter coefficients when the target zone and all of its neighboring zones are interior zones, according to one or more embodiments.

[0025] [Figure 11B] FIG. 11B illustrates an example of filter coefficient definitions when the zone of interest and its neighboring zones include both an inner zone and an extended zone, according to one or more embodiments.

[0026] [Figure 11C] FIG. 11C illustrates an example of filter coefficient definition when the target zone is the top left corner zone, according to one or more embodiments.

[0027] [Figure 12A] FIG. 12A illustrates an example of the starting point of each zone, according to one or more embodiments. [Figure 12B] FIG. 12B illustrates an example of the starting point of each zone, according to one or more embodiments. [Figure 12C] FIG. 12C illustrates an example of the starting point of each zone, according to one or more embodiments. [Figure 12D] FIG. 12D illustrates an example of the starting point of each zone, according to one or more embodiments.

[0028] [Figure 13] FIG. 13 is a flowchart of an exemplary process for local dimming in accordance with one or more embodiments.

[0029] To facilitate understanding, the same reference numbers have been used, where possible, to designate identical elements common to the figures. It is anticipated that elements disclosed in one embodiment may be beneficially used in other embodiments without specific mention. Reference numbers may be supplemented with subscripts to distinguish identical elements from one another. The drawings referred to herein should not be understood as being drawn to scale unless specifically noted. Additionally, the drawings are often simplified, omitting details or components for clarity of presentation and explanation. The drawings and discussion serve to explain the principles discussed below. DETAILED DESCRIPTION OF THE INVENTION

[0030] The following detailed description is merely exemplary in nature and is not intended to limit the disclosure and its application and uses.Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding background, summary, brief description of the drawings or the following detailed description.

[0031] In the following detailed description of the embodiments, many specific details are presented to provide a deeper understanding of the disclosed technology. However, it will be apparent to those skilled in the art that the disclosed technology may be implemented without using these specific details. In other instances, well-known configurations are not described in detail to avoid unnecessarily complicating the description.

[0032] As used herein, the term "coupled" means directly connected or connected via one or more intervening components or circuits. Additionally, throughout the application, ordinal numbers (e.g., first, second, third, etc.) may be used as adjectives for elements (i.e., any nouns in the application). The use of ordinal numbers is not intended to imply or create a particular ordering of any elements, nor is it intended to limit any element to only a single element, unless expressly disclosed, for example, by the use of "before," "after," "single," and other similar terms. Rather, the use of ordinal numbers is intended to distinguish between elements. For example, a first element is distinct from a second element, and a first element may encompass more than one element and may follow (or precede) a second element in the ordering of elements.

[0033] This disclosure provides various techniques for realizing a local dimming function. Local dimming, as used herein, refers to a technique for individually controlling each light source (e.g., a light-emitting diode (LED)) in a 2D light source array according to input image data. By using the local dimming function, high dynamic contrast and low power consumption can be effectively achieved.

[0034] 1A illustrates an example configuration of a display device 100 that supports local dimming, in accordance with one or more examples of the present disclosure. In the illustrated example, the display device 100 includes a light-transmissive display panel 110 (e.g., a light-transmissive liquid crystal display (LCD) panel) and a backlight device 120 configured to illuminate the display panel 110. The backlight device 120 includes a two-dimensional array of light sources 122, each of which may include a light-emitting diode (LED) or other type of light-emitting element.

[0035] To implement a local dimming function, the brightness level of each light source 122 may be individually controlled based on the input image data. In some implementations, the brightness levels of light sources 122 illuminating portions of the display panel 110 that display bright images may be increased, while the brightness levels of light sources 122 illuminating portions of the display panel 110 that display dark images may be decreased, to enhance the contrast of the displayed image.

[0036] In various implementations, the brightness levels of the light sources 122 may be controlled based on "zones" defined for the display panel 110. The zones 112 may be defined in a matrix such that there is a one-to-one relationship between the zones 112 and the light sources 122, and the brightness level of each light source 122 may be controlled based on the image displayed in the corresponding zone 112.

[0037] FIG. 1B illustrates an example arrangement of zones 112 and light sources 122 on a display panel 110 according to one or more examples of the present disclosure. In the illustrated example, the zones 112 are square-shaped and of the same size, and the projection of each light source 122 onto the display panel 110 is located at the center of the corresponding zone 112. Note that if the projection of a given light source 122 falls within a given zone 112, the zone 112 may be referred to as the corresponding zone of the given light source 122. In FIG. 1B, reference numeral 112a refers to the corresponding zone of the light source 122a. In one implementation, the brightness level of each light source 122 may be controlled based on pixel data of pixels located in the corresponding zone 112 of the given light source 122 and pixels located in zones 112 adjacent to the corresponding zone 112. For example, in the example illustrated in FIG. 1B, the brightness level of the light source 122a may be controlled based on pixel data of pixels located in the corresponding zone 112a and eight zones 112 adjacent to the corresponding zone 112a. Box 130 indicates a 3x3 zone associated with controlling the brightness level of light source 122a.

[0038] Because the effect of the local dimming function varies depending on the light distribution characteristics (or light directionality) of the light source 122, it would be advantageous to control the brightness level of the light source 122 depending on the light distribution characteristics of the light source 122. One way to achieve this is to filter pixel data depending on the light distribution characteristics of the light source 122. In one implementation, the brightness level of a given light source 122 may be controlled by defining filter coefficients based on the light distribution characteristics of the light source 122, applying the filter coefficients to pixel data of pixels located in the corresponding zone 112 a and its adjacent zones 112, thereby generating filtered pixel data, and determining the brightness level of the light source 122 based on the filtered pixel data.

[0039] FIG. 2 illustrates example filter coefficients used to control the brightness level of the light source 122a (illustrated in FIG. 1B ) according to one or more examples of the present disclosure. In FIG. 2 , reference numeral 114a denotes the center of the corresponding zone 112a of the light source 122a, which corresponds to the projection position of the light source 122a on the display panel 110. In the illustrated example, the filter coefficients assigned to pixels in the corresponding zone 112a and its adjacent zones 112 depend on the distance between the pixel and the center 114a of the corresponding zone 112a. The filter coefficient for the pixel located at the center 114a of the corresponding zone 112a is W (e.g., 1.0), which is the maximum filter coefficient. The filter coefficients determined for other pixels in the corresponding zone 112a and its adjacent zones 112 increase as the distance between the pixel and the center 114a of the corresponding zone 112a decreases. Note that the filter coefficients are determined symmetrically with respect to the center 114a of the corresponding zone 112a in view of the light distribution characteristics of the light source 122a. The filter coefficients used to control the brightness levels of the other light sources 122 may be determined in a similar manner.

[0040] One problem is that the arrangement of light sources in a backlight device may not match the arrangement of the zones. FIG. 3A illustrates an example configuration of such a display device, designated 200, according to one or more examples of the present disclosure. The display device 200 includes a display panel 210 in which zones 212 are defined in rows and columns, and a backlight device 220 including an array of light sources 222. In the illustrated example, the zones 212 are defined with the same size and shape (e.g., the same width and height), as in a typical implementation. The light sources 222 are spaced at regular intervals but are not necessarily located at the centers of the corresponding zones 212. For example, the outermost light sources 222 are located near the edges of the display panel 210. This situation may arise due to physical constraints on the arrangement of the light sources 222, such as the minimum possible spacing between adjacent light sources 222 or the commercial availability of the backlight device 220. Placing the outermost light sources 222 near the edges of the display panel 210 may also help illuminate the periphery of the display panel 210 with sufficient brightness.

[0041] FIG. 3B is an expanded view of an example arrangement of zones 212 and light sources 222, according to one or more examples of the present disclosure. Box 230 depicts a 3×3 zone associated with controlling the brightness level of light source 222a, including the corresponding zone 212a and its adjacent zones 212. Note that in implementations where zones 212 are defined with the same size and shape and the outermost light sources 222 are located near the edge of the display panel 210, the light sources 222 may not be located at the centers of their corresponding zones 212. For example, in the example illustrated in FIG. 3B, light source 222a, located in the second row from the top and second column from the left, may not be located at the center of the corresponding zone 212, which is located in the second row from the top and second column from the left in the array of zones 212. The deviation between the location of each light source 222 and the center of its corresponding zone 212 may degrade the quality of a display image displayed using the local dimming function. This is because the filter coefficients used to control the brightness level of each light source 222 are determined symmetrically with respect to the center of the corresponding zone 212 of that light source 222 , but asymmetrically with respect to the position of that light source 222 .

[0042] In one aspect, the present disclosure provides a local dimming technique for improving image quality even when the arrangement of light sources in a backlight device does not match the arrangement of zones defined for a display panel. The present disclosure recognizes that defining zones with the same size and shape (or the same width and height) on a display panel can result in a discrepancy between the location of each light source and the center of its corresponding zone. Accordingly, in one or more embodiments of the present disclosure, zones used to implement a local dimming function may be defined such that the outermost zone corresponding to the outermost light source of a light source array is a different size or shape from the inner zones corresponding to the inner light sources of the light source array. The inner zones may be defined such that the inner light source of the light source array is located at the center of each inner zone. The outermost zone may be defined as each region where an "extended" zone overlaps with the display area of ​​the display panel. Here, the extended zone has the same size and shape as its adjacent inner zone, and the outermost light source is located at the center of each extended zone. The filter coefficients used to control each inner light source may be defined symmetrically with respect to the center of the inner zone corresponding to that inner light source. The filter coefficients used to control each outermost light source may be defined symmetrically about the center of that light source's corresponding "extended" zone, allowing for control of the brightness level of the outermost light source to match the light distribution characteristics of the outermost light source. Various embodiments of the present disclosure are described in detail below.

[0043] FIG. 4A illustrates an example of defining zones for a display panel, according to one or more embodiments. In the illustrated embodiment, reference numeral 310 denotes a display area of ​​the display panel. The display area 310 is an area where pixels are arranged to display an image. The display area 310 may be a portion of a display panel, and an array of zones is defined in the display panel by partitioning the display area 310. The zones defined in the display area 310 include an inner zone 312 and outermost zones 314, 316, and 318. The inner zone 312 corresponds to an internal light source 322 in the light source array and is located away from the edge of the display area 310. In various embodiments, the inner zone 312 is substantially rectangular. In the illustrated embodiment, the inner zone 312 is square. Although FIG. 4A illustrates all of the inner zones 312 as having the same size and shape, the size or shape of the inner zones 312 may be non-uniform, as long as the inner zones 312 form a rectangular array. In some implementations, the horizontal widths of the interior zones 312 of the first set of columns may differ from the horizontal widths of the interior zones 312 of the second set of columns. Additionally, or alternatively, the vertical heights of the interior zones 312 of the first set of rows may differ from the vertical heights of the interior zones 312 of the second set of rows.

[0044] The outermost zones 314, 316, and 318 are arranged along the edges of the display area 310. The outermost zones 314, 316, and 318 differ in size or shape from the adjacent interior zones 312. The outermost zone 314, located at the top edge of the display area 310, may also be referred to as the top edge zone 314. Similarly, the outermost zone 316, located at a side edge of the display area 310, may also be referred to as the side edge zone 316, and the outermost zones 318 (one shown) located at the corners of the display area 310 may also be referred to as the corner zones 318.

[0045] The outermost zone 314 is defined as the area where the "extended" zone 334 and the display area 310 overlap. Here, the "extended" zones 334 have the same size and shape as the inner zones 312 that are adjacent to the outermost zone 314, and the outermost light sources 324 of the light source array are each located at the center of the "extended" zone 334. It should be noted that the concept of the "extended" zone 334 is introduced only to define the outermost zone 314; therefore, no pixels exist within the extended zone 334 but outside the display area 310.

[0046] Similarly, outermost zone 316 is defined as the overlapping region of expanded zone 336 and display area 310. Here, expanded zone 336 has the same size and shape as the inner zones 312 that are respectively adjacent to outermost zone 316, and each of the outermost light sources 326 of the light source array is located at the center of "expanded" zone 336. Furthermore, outermost zone 318 is defined as the overlapping region of expanded zone 338 and display area 310. Here, expanded zone 338 has the same size and shape as the inner zone 312 that is diagonally adjacent to outermost zone 318. Although not shown in FIG. 4A , one skilled in the art will understand that other inner zones and other outermost zones are similarly defined in the remainder of display area 310.

[0047] 4B , the filter coefficients used to control the brightness level of each internal light source 322 may be defined symmetrically about the center of the corresponding internal zone 312 for that internal light source 322. For example, box 330 shows a 3×3 zone associated with controlling the brightness level of light source 322a. Here, the 3×3 zone includes the corresponding zone 312a, three internal zones 312 adjacent to the corresponding zone 312a, and five “extended” zones 334, 336, and 338 adjacent to the corresponding zone 312a. The filter coefficients used to control the brightness level of internal light source 322a may be defined symmetrically about the center of the corresponding internal zone 312a. Similarly, the filter coefficients used to control the brightness level of each of the outermost light sources 324, 326, and 328 may be defined symmetrically about the corresponding “extended” zone 334, 336, or 338 for that outermost light source. By defining the filter coefficients in this way, it becomes possible to implement a local dimming function based on the light distribution characteristics of the light sources 322, 324, 326, and 328, and the quality of the display image generated by the local dimming function is improved.

[0048] 5 illustrates an example configuration of a display device 1000 in accordance with one or more embodiments. In the illustrated embodiment, the display device 1000 includes a display panel 400 and a display driver 600. The display panel 400 includes a display area 405 in which pixels are arranged to display an image. The display panel 400 may be a light-transmissive display panel, such as an LCD panel. The display driver 600 is configured to drive the display panel 400 to display a desired image on the display panel 400.

[0049] The display device 1000 further includes a backlight device 500 and a backlight driver 700. The backlight device 500 is configured to illuminate the display area 405 of the display panel 400. The backlight device 500 includes an array of light sources 505. Note that only a portion of the light sources 505 is shown in FIG. 5 because the light sources 505 are located behind the display panel 400. In one implementation, each light source 505 may include an LED or other type of light source. The backlight device 500 is coupled to the backlight driver 700. The backlight driver 700 is configured to drive the light sources 505 of the backlight device 500 under the control of the display driver 600 such that each light source 505 emits light at a brightness specified by the display driver 600.

[0050] FIG. 6 illustrates an example arrangement of light sources 505 in a backlight device 500 and an example definition of zones for a display panel 400, according to one or more embodiments. The light sources 505 are arranged in rows and columns. While FIG. 6 illustrates 288 light sources 505, one skilled in the art will understand that the backlight device 500 may include fewer or more than 288 light sources 505. In actual implementations, the backlight device 500 may include hundreds or thousands of light sources 505. Zones are defined in the display panel 400 by dividing the display area 405. In the illustrated embodiment, the zones are substantially rectangular in shape. The defined zones include an inner zone 410 and outermost zones 420, 430, 440, 450, 460, 470, 480, and 490. The inner zones 410 correspond to the internal light sources of the array of light sources 505 and are located away from the edges of the display area 405. 6 illustrates all of the internal zones 410 as having the same size and shape (or the same width and height), the size and / or shape of the internal zones 410 may be non-uniform, so long as the internal zones 410 form a rectangular array. In some implementations, the horizontal widths of the internal zones 410 in a first set of columns may be different from the horizontal widths of the internal zones 410 in a second set of columns. Additionally, or alternatively, the vertical heights of the internal zones 410 in a first set of rows may be different from the vertical heights of the internal zones 312 in a second set of rows.

[0051] Outermost zones 420, 430, 440, 450, 460, 470, 480, and 490 are located along the edges of viewing area 405 and correspond respectively to the outermost light sources of array of light sources 505. Outermost zones 420, 430, 440, 450, 460, 470, 480, and 490 differ in size or shape (or width and / or height) from their adjacent interior zones 410.

[0052] The outermost zones 420, 430, 440, and 450 are located at the edges of the display area 405. More specifically, the outermost zone 420 is located at the top edge of the display area 405, and therefore may also be referred to as the top edge zone 420. The outermost zone 430 is located at the bottom edge of the display area 405, and therefore may also be referred to as the bottom edge zone 430. The outermost zone 440 is located at the left edge of the display area 405, and therefore may also be referred to as the left edge zone 440. The outermost zone 450 is located at the right edge of the display area 405, and therefore may also be referred to as the right edge zone 450.

[0053] The outermost zones 460, 470, 480, and 490 are located at the corners of the display area 405. The outermost zone 460 is located in the upper left corner of the display area 405, and therefore may also be referred to as the upper left corner zone 460. The outermost zone 470 is located in the upper right corner of the display area 405, and therefore may also be referred to as the upper right corner zone 470. The outermost zone 480 is located in the lower left corner of the display area 405, and therefore may also be referred to as the lower left corner zone 480. The outermost zone 490 is located in the lower right corner of the display area 405, and therefore may also be referred to as the lower right corner zone 490.

[0054] 7A illustrates a close-up view of the upper left corner of the display area 405, according to one or more embodiments. The internal zones 410 each correspond to an internal light source 510, and each internal light source 510 is located at the center of its corresponding internal zone 410. The width and height of the internal zones 410 are respectively Xsize zone and Ysize zone The inner zone 410 may be square in shape, in other words, Xsize zone and Ysize zone may be identical to each other.

[0055] As discussed in connection with FIGS. 4A and 4B , the top edge zone 420, the left edge zone 440, and the top-left corner zone 460 are defined using "extended" zones that have the same size and shape as the adjacent interior zones 410. More specifically, the top edge zones 420 are each defined as the overlapping regions of the top edge extension zones 422 and the display area 405. Here, the top edge extension zones 422 have the same size and shape as the adjacent interior zones 410, and the top edge outermost light sources 520 are each located at the centers of the top edge extension zones 422. The left edge zones 440 are each defined as the overlapping regions of the left edge extension zones 422 and the display area 405. Here, the left edge extension zones 442 have the same size and shape as the adjacent interior zones 410, and the left edge outermost light sources 540 are each located at the centers of the left edge extension zones 442. The top-left corner zone 460 is defined as the area where the top-left corner extended zone 462 and the display area 405 overlap. Here, the top-left corner extended zone 462 has the same size and shape as the internal zone 410 diagonally adjacent to the top-left corner zone 460, and the top-left corner outermost light source 560 is located at the center of the top-left corner extended zone 462. In FIG. 7A , “offset1” is the vertical offset between the top edge of the display area 405 and the top edges of the extended zones 422 and 462, and “offset3” is the horizontal offset between the left edge of the display area 405 and the left edges of the extended zones 422 and 462.

[0056] 7B illustrates an enlarged view of the top right corner of the display area 405, in accordance with one or more embodiments. The right edge zone 450 and the top right corner zone 470 are defined in a manner similar to the top edge zone 420, left edge zone 440, and top left corner zone 460 illustrated in FIG. 7A. More specifically, the right edge zone 450 is defined as the overlapping region of the right edge extension zone 452 and the display area 405. Here, the right edge extension zone 452 has the same size and shape as the interior zone 410 adjacent to the right edge zone 450, and the right edge outermost light source 550 is located at the center of the right edge extension zone 452. The top right corner zone 470 is defined as the overlapping region of the top right corner extension zone 472 and the display area 405. Here, the upper right corner extended zone 472 has the same size and shape as the inner zone 410 diagonally adjacent to the upper right corner zone 470, and the upper right corner outermost light source 570 is located at the center of the upper right corner extended zone 472. In Figure 7B, "offset4" is the horizontal offset between the right edge of the display area 405 and the right edges of the extended zones 452 and 472.

[0057] 7C illustrates a close-up view of the bottom left corner of the display area 405, in accordance with one or more embodiments. The bottom edge zone 430 and the bottom left corner zone 480 are defined in a manner similar to the top edge zone 420 and the top left corner zone 460 illustrated in FIG. 7A. More specifically, the bottom edge zone 430 is defined as the overlapping region of the bottom edge extension zone 432 and the display area 405. Here, the bottom edge extension zone 432 has the same size and shape as the interior zone 410 adjacent to the bottom edge zone 430, and the bottom edge outermost light source 530 is located at the center of the bottom edge extension zone 432. The bottom left corner zone 480 is defined as the overlapping region of the bottom left corner extension zone 482 and the display area 405. Here, the bottom-left corner extended zone 482 has the same size and shape as the inner zone 410 diagonally adjacent to the bottom-left corner zone 480, and the bottom-left corner outermost light source 580 is located at the center of the bottom-left corner extended zone 482. In Figure 7C, "offset2" is the vertical offset between the bottom edge of the display area 405 and the bottom edges of the extended zones 432 and 482.

[0058] 7D illustrates a close-up view of the lower right corner of the display area 405, in accordance with one or more embodiments. The lower right corner zone 490 is defined in a manner similar to the upper right corner zone 470 illustrated in FIG. 7B. More specifically, the lower right corner zone 490 is defined as the overlapping region of the display area 405 with the lower right corner extension zone 492. Here, the lower right corner extension zone 492 has the same size and shape as the interior zone 410 diagonally adjacent to the lower right corner zone 490, and the lower right corner outermost light source 590 is located at the center of the lower right corner extension zone 492.

[0059] 8 illustrates an example configuration of a display driver 600 according to one or more embodiments. In the illustrated embodiment, the display driver 600 includes an image processing circuit 610, a driver circuit 620, a backlight control circuit 630, and a memory device 660. The display driver 600 is configured to receive input image data corresponding to a display image. In one implementation, each pixel of the display panel 400 may include red (R), green (G), and blue (B) sub-pixels configured to display red, green, and blue colors, respectively, and the input image data may include R, G, and B gradations for each pixel, where the R, G, and B gradations specify the luminance levels of the R, G, and B sub-pixels, respectively.

[0060] The image processing circuit 610 is configured to perform image processing on the input image data to generate processed image data. The image processing performed by the image processing circuit 610 may include color adjustment, demurration correction, deburn correction, image scaling, gamma conversion, and other image processing.

[0061] The driver circuit 620 is configured to receive the processed image data from the image processing circuit 610 and drive each pixel of the display panel 400 based at least in part on the processed image data. In one implementation, each pixel of the display panel 400 may comprise R, G, and B sub-pixels, and the processed image data may include gray levels for the R, G, and B sub-pixels of each pixel. The driver circuit 620 may be configured to drive or update the R, G, and B sub-pixels of each pixel based at least in part on the processed image data to control the brightness levels of the R, G, and B sub-pixels as specified by the processed image data.

[0062] The backlight control circuit 630 is configured to generate a backlight value for each light source 505 based at least in part on the input image data and provide the backlight value to a backlight driver 700 to control the brightness level of each light source 505 (shown in FIGS. 5 and 6 ) of the backlight device 500. The backlight value for each light source 505 may indicate a specified brightness level for each light source 505. The backlight driver 700 drives each light source 505 based on the backlight value, causing each light source 505 to emit light at the specified brightness level. The backlight value is generated by a local dimming function based on the input image data. As will be described in more detail below, the local dimming function is implemented using an inner zone 410 and outermost zones 420, 430, 440, 450, 460, 470, 480, and 490 shown in FIGS. 6 and 7A-7D.

[0063] In the illustrated embodiment, the backlight control circuit 630 includes an image analysis circuit 640 and a backlight value generation circuit 650. The image analysis circuit 640 is configured to analyze input image data and generate a local average picture level (APL) for each zone (including the inner zone 410 and the outermost zones 420, 430, 440, 450, 460, 470, 480, and 490) based on the input image data. The local APL for a zone may be a value representing the luminance of an image displayed in that zone and adjacent portions of the display area 405. In some implementations, the local APL for each zone may be provided to the image processing circuit 610, which may perform image processing on the input image data depending on the local APL. The image analysis circuit 640 is further configured to generate a base backlight value based on the analysis of the input image data. The backlight value generation circuit 650 is configured to generate a backlight value for each light source 505 by modifying the base backlight value based on the display luminance value (DBV). The DBV as used herein is a value specifying a desired display brightness level of the display device 1000. Here, the display brightness level as used herein refers to the overall brightness level of the display image displayed on the display panel 400. The DBV may be generated by an external controller based on a user operation. For example, when a command to adjust the display brightness level of the display device 1000 is manually input to an input device, the DBV may be generated based on the command. In one implementation, the backlight value generation circuit 650 may be configured to generate a backlight value for each light source 505 by multiplying the base backlight value by a multiplication coefficient determined based on the DBV.

[0064] 9 illustrates an example configuration of the image analysis circuit 640 according to one or more embodiments. In the illustrated embodiment, the image analysis circuit 640 is configured to receive coordinates of a target light source, which is the light source for which a base backlight value is currently being calculated. The corresponding zone of the target light source may also be referred to as the target zone. In response to receiving the coordinates of the target light source, the image analysis circuit 640 is configured to calculate a base backlight value of the target light source and a local APL for the target zone. In the illustrated embodiment, the image analysis circuit 640 includes a filter circuit 642, an integrator circuit 644, and an APL and backlight value calculator 646.

[0065] The filter circuit 642 is configured to extract pixel data used to calculate the basic backlight value of the target light source and the local APL of the target zone, and to filter the pixel data to generate filtered pixel data, where the pixel data of a pixel indicates the luminance level of the pixel, which may be calculated from the R, G, and B gradations of the pixel. The filtered pixel data is provided to the integrator circuit 644.

[0066] FIG. 10 illustrates an example of defining filter coefficients used for filtering, according to one or more embodiments. When calculating the basic backlight value of the target light source (which is located at the center of the target zone) and the local APL of the target zone, filtering is performed on pixel data of pixels located in the target zone and its eight neighboring zones, which are arranged in a 3-by-3 grid. In FIG. 10, reference numeral 800 indicates a 3×3 zone related to filtering for the target zone, reference numeral 810 indicates the target zone, reference numeral 815 indicates the center of the target zone 810, and reference numeral 820 indicates neighboring zones of the target zone 810. In the illustrated example, the x and y coordinates of the pixel located at the center 815 of the target zone 810 are (x y ). C ,y C ), and the filter coefficient of the pixel located at the center 815 of the target zone 810 is the largest filter coefficient W(x C ,y C) (e.g., 1.0). The filter coefficients defined for other pixels within the target zone 810 and its neighboring zones 820 increase as the respective distances between the pixel and the center 815 of the target zone 810 decrease. Note that while FIG. 10 illustrates the target zone and all eight of its neighboring zones as interior zones, it is possible for some of the target zone 810 and its eight neighboring zones 820 to be extended zones (as illustrated in FIGS. 6 and 7A-7D). The details of calculating the filter coefficients in such cases are described in more detail below.

[0067] Returning to FIG. 9 , filter circuit 642 is configured to store filter data 648 used to generate filter coefficients assigned to pixels in the target zone and its adjacent zones through arithmetic operations. Because there may be a large number of pixels in the target zone and its adjacent zones, storing the original filter coefficients assigned to the pixels in the target zone and its adjacent zones may be impractical. To address this, filter circuit 642 may be configured to store filter data 648 and generate filter coefficients for each pixel in the target zone and its adjacent zones from filter data 648. Filter data 648 may include sufficient information to reconstruct the filter coefficients. In some implementations, filter data 648 may include filter coefficients assigned to certain (but not all) of the pixels in the target zone and its adjacent zones, and filter circuit 642 may be configured to calculate filter coefficients assigned to the remaining pixels by interpolating the filter coefficients assigned to the certain pixels. In other implementations, filter data 648 may be configured to store the filter coefficients themselves assigned to the pixels in the target zone and its adjacent zones.

[0068] In connection with the three-by-three arrangement of the target zone and its neighboring zones, the target zone 810 and all of its neighboring zones 820 may be interior zones, or some of the target zone 810 and its neighboring zones 820 may be extended zones (as shown in Figures 6 and 7A-7D). Figures 11A-11C illustrate examples of target zones and their neighboring zones, according to one or more embodiments.

[0069] 11A illustrates an example of filter coefficient definition for a target zone and all of its neighboring zones being interior zones 410, according to one or more embodiments. Here, reference numeral 800a denotes a 3×3 zone associated with filtering for the target zone, and reference numeral 815a denotes the center of the target zone. When all of the 3×3 zone 800a are interior zones 410, filter coefficients are calculated for all pixels within the 3×3 zone 800a using filter data 648.

[0070] FIG. 11B illustrates an example of filter coefficient definition for a case in which a target zone and its neighboring zones include both interior and extended zones, according to one or more embodiments. In FIG. 11B, reference numeral 800b denotes a 3×3 zone associated with filtering the target zone, and reference numeral 815b denotes the center of the target zone. In the illustrated example, the 3×3 zone 800b includes four interior zones 410 and five extended zones 422, 442, and 462. Here, two extended zones 422 are used to define two top edge zones 420, two extended zones 442 are used to define two left edge zones 440, and extended zone 462 is used to define the top left corner zone 460. In this case, filter coefficients are calculated for pixels located in the portion of the display area 405 that is within the 3×3 zone 800b. Note that no pixels exist outside the display area 405.

[0071] The filter coefficients for the pixels in the four interior zones 410, the two top edge zones 420, the two left edge zones 440, and the upper-left corner zone 460 are calculated to be the same as the filter coefficients calculated for the corresponding pixels in the 3×3 zone 800 shown in Figure 10, which is an interior zone. For example, the filter coefficients for the pixels in the upper-left corner zone 460, which is the lower-right portion of the zone located at the upper left of the 3×3 zone 800b, are determined to be the same as the filter coefficients for the corresponding pixels in the lower-right portion of the zone located at the upper left of the 3×3 interior zone 800 shown in Figure 10.

[0072] If the target zone is one of the outermost zones, some of the 3×3 zones involved in filtering may be "dummy" zones with no pixels present. FIG. 11C illustrates an example of defining filter coefficients when the target zone is the top-left corner zone 460, according to one or more embodiments. In FIG. 11C, reference numeral 800c indicates the 3×3 zone involved in filtering the target zone, and reference numeral 815c indicates the center of the extended zone used to define the target zone. In the illustrated example, the 3×3 zone involved in filtering 800c includes five "dummy" zones 830, one interior zone 410, one top edge zone 420, one left edge zone 440, and one top-left corner zone 460. In this case, similar to the case shown in Fig. 11B, the filter coefficients of the pixels in the interior zone 410, the top edge zone 420, the left edge zone 440, and the top left corner zone 460 are calculated to be the same as the filter coefficients calculated for the corresponding pixels in the 3x3 zone 800 shown in Fig. 10. For example, the filter coefficients of the pixels in the top left corner zone 460, which is the lower right part of the target zone, are calculated to be the same as the filter coefficients of the corresponding pixels in the lower right part of the zone located at the center of the 3x3 zone 800.

[0073] 12A, 12B, 12C, and 12D illustrate examples of "starting points" for each zone, including the inner zone and the outermost zone, according to one or more embodiments. The "starting point" of a zone is the pixel position in the zone where calculation of filter coefficients for pixels in the zone should begin. In the illustrated embodiment, the "starting point" of the zone is defined in the upper left corner of the zone, and the order of calculation of filter coefficients for pixels in each zone is left-to-right and top-to-bottom, in accordance with typical circuit operation.

[0074] 12A, 12B, 12C, and 12D, reference numeral 414 denotes the start point of the interior zone 410. The start point 414 of the interior zone 410 is located in the upper left corner of each interior zone 410. The filter circuit 642 (shown in FIG. 9) is configured to sequentially calculate filter coefficients for each pixel of the interior zone 410 based on the location of the start point of the interior zone.

[0075] Furthermore, reference numerals 424, 444, and 464 in Figure 12A indicate the start points of the outermost zones 420, 440, and 460, respectively, and reference numerals 454 and 474 in Figure 12B indicate the start points of the outermost zones 450 and 470. Furthermore, reference numerals 434 and 484 in Figure 12C indicate the start points of the outermost zones 430 and 480, and reference numeral 494 in Figure 12D indicates the start point of the outermost zone 490. The start points 424, 434, 444, 454, 464, 474, 484, and 494 of the outermost zones 420, 430, 440, 450, 460, 470, 480, and 490 are located in the upper left corners of each of the outermost zones 420, 430, 440, 450, 460, 470, 480, and 490. The filter circuit 642 (shown in FIG. 9) is configured to sequentially calculate filter coefficients for each pixel of the outermost zones 420, 430, 440, 450, 460, 470, 480 and 490 based on the locations of the starting points of the outermost zones 420, 430, 440, 450, 460, 470, 480 and 490.

[0076] The location of the starting point of a given outermost zone in an extended zone defining that outermost zone indicates which of the filter coefficients shown in FIG. 10 should be used to filter the pixel data of the pixels in that outermost zone. For example, the location of the starting point 464 of the upper-left corner zone 460 in extended zone 462 indicates which of the filter coefficients shown in FIG. 10 should be used to filter the pixel data of the pixels in the upper-left corner zone 460 (see also FIGS. 11B and 11C). The location of the starting point 464 of the upper-left corner zone 460 in extended zone 462 may correspond to the offset amounts "offset1" and "offset3" shown in FIG. 7A. The same applies to the starting points of the other outermost zones 420, 430, 440, 450, 470, 480, and 490 with respect to the offset amounts "offset1" and "offset3" shown in FIGS. 7A-7D.

[0077] In one implementation, the filter circuit 642 may be configured to calculate filter coefficients for pixels in each outermost zone based on the location of the starting point of the outermost zone in the extended zone that defines the outermost zone. For example, the filter circuit 642 may be configured to calculate filter coefficients for pixels in the top-left corner zone 460 based on the location of the starting point 464 of the top-left corner zone 460 in the extended zone 462.

[0078] 9, the filter circuit 642 is configured to receive initialization values ​​corresponding to the positions of the starting points 414, 424, 444, and 464 of the inner zone 410, the top edge zone 420, the left edge zone 440, and the top-left corner zone 460, and calculate filter coefficients for pixels in each zone (including the inner zone and the outermost zone). In one implementation, the storage device 660 illustrated in FIG. 8 may be configured to store the initialization values ​​and provide the initialization values ​​to the filter circuit 642. It should be noted that the positions of the starting points of the inner zone 410, the top edge zone 420, the left edge zone 440, and the top-left corner zone 460 contain sufficient information to calculate filter coefficients for pixels in all zones, including the inner zone and the outermost zone. This is because (a) the position of the start point 474 of the upper right corner zone 470 in the extended zone 472 is equivalent to the position of the start point 424 of the upper edge zone 420 in the extended zone 422 (see FIG. 12B ); (b) the location of the start point 484 of the bottom left corner zone 480 in the extended zone 482 is equivalent to the location of the start point 444 of the left edge zone 440 in the extended zone 442 (see FIG. 12C ); (c) the locations of the starting points 434, 454, and 494 of the bottom edge zones 430, 459, and 490 are at the upper left corners of the extension zones 432, 452, and 492, respectively (see Figures 12B, 12C, and 12D); and (d) The end of the pixel data for each pixel row, the end of the pixel data for each pixel column, and the end of the pixel data for each outermost zone indicate the end of the calculation of the filter coefficients for each pixel row, each pixel column, and each outermost zone, respectively.

[0079] The filter circuit 642 is further configured to apply a filter coefficient to the pixel data of each zone, thereby generating filtered pixel data. The filter circuit 642 is further configured to provide the filtered pixel data to an accumulation circuit 644.

[0080] The accumulator circuit 644 is configured to, for each zone, accumulate the values ​​of the filtered pixel data of a 3x3 zone that includes the zone and its eight adjacent zones, and calculate a filtered sum for each zone. The filtered sum for each zone is the sum of the values ​​of the filtered pixel data of the pixels in the 3x3 zone that includes the zone and its eight adjacent zones. In one implementation, the filtered sum for a target zone (which can be either an inner zone or an outermost zone) may be calculated according to the following equation (1):

number

[0081] Below is the zone index (X LS ,Y LS ) where X LS is the X index that indicates the horizontal position of the zone in the array, and is an integer between 0 and M-1, inclusive, where M is the number of columns of the zone in the display area 405. LS The target zone is (X LS +1) column. LS is the Y index that indicates the vertical position of the zone's array and is an integer between 0 and N-1, inclusive, where N is the number of rows of the zone in the display area 405. LS The target zone is (Y LS +1)th line. The notation used in the following explanation is as follows:

[0082] (x,y) are x and y coordinates in the x and y coordinate system defined for the filter shown in Figure 10, and w(x,y) is the filter coefficient for the pixel at coordinate (x,y) defined in the x and y coordinate system shown in Figure 10. Note that the origin O of the x and y coordinate system is at the upper left corner of the zone of interest. (X,Y) are the x and y coordinates in the coordinate system defined for the display area 405 of the display panel 400 as shown in Figure 6.

[0083] xsize filter is the horizontal size of the 3x3 zone including the target zone and its adjacent zones, and ysize filter is the vertical size of the 3x3 zone. filter and vertical size ysize filter are the horizontal and vertical dimensions of the internal and extended zones (see Figure 7A). zone and Ysize zone It is expressed as follows using xsize filter = 3×Xsize zone ysize filter = 3×Ysize zone

[0084] X filter and Y filter are the x and y coordinates of the upper left corner of the 3x3 zone including the target zone and its adjacent zones in the coordinate system shown in Figure 10. filter and Y filter xsize filter and ysize filter It is expressed as follows using (X filter , Y filter ) = (-xsize filter / 3, -ysize filter / 3)

[0085] The target zone is the zone index (X LS ,Y LS), if it is an internal zone with the filtered sum SUM(X LS ,Y LS ) is calculated according to the following formula (2):

number

[0086] If the target zone is the top-left corner zone 460 having a zone index (0,0), the filtered sum SUM(0,0) is calculated according to the following formula (3):

number

[0087] The target zone is the zone index (X LS , 0), the filtered sum SUM(X LS , 0) is calculated according to the following formula (4):

number

[0088] If the target zone is the upper right corner zone 470 having a zone index (N-1,0), the filtered sum SUM(N-1,0) is calculated according to the following formula (5):

number

[0089] The target zone is the zone index (0,Y LS ), if the filtered sum SUM(0,Y LS ) is calculated according to the following formula (6):

number

[0090] The target zone is the zone index (N-1,Y LS ), if the filtered sum SUM(N-1,Y LS ) is calculated according to the following formula (7):

number

[0091] If the target zone is the bottom left corner zone 480 having zone index (0, M-1), the filtered sum SUM(0, M-1) is calculated according to the following formula (8):

number

[0092] The target zone is the zone index (X LS ,Y LS ), if the filtered sum SUM(X LS ,Y LS ) is calculated according to the following formula (9):

number

[0093] If the target zone is the bottom right corner zone 490 having zone index (N-1, M-1), the filtered sum SUM(N-1, M-1) is calculated according to the following formula (10):

number

[0094] 9 , the APL and BL calculator circuit 646 receives the filtered sum for each zone from the accumulator circuit 644 and calculates a local APL for each zone based on the filtered sum for that zone. As described above, the local APL for a zone may be a value representing the luminance of the image displayed in that zone and in portions of the display area 405 adjacent to that zone. In one implementation, the APL and BL calculator circuit 646 may be configured to calculate the local APL for each zone by normalizing the filtered sum for that zone by a normalization value determined for that zone, e.g., by dividing the filtered sum for that zone by the normalization value determined for that zone. The normalization value for a given target zone corresponds to the sum of the filter coefficients for the pixels in the target zone and its adjacent zones multiplied by the maximum value of the pixel data. In one implementation, the normalization value for the target zone is the sum of the filter coefficients for the pixels in the target zone and its adjacent zones multiplied by the maximum value of the pixel data. In one or more embodiments, the normalization value for the target zone may be expressed as follows:

number

[0095] In one implementation, the APL and BL calculator circuit 646 may be configured to receive normalization values ​​for the interior zone 410, the top edge zone 420, the bottom edge zone 430, the left edge zone 440, the bottom edge zone 430, the left edge zone 440, the right edge zone 450, the top-left corner zone 460, the top-right corner zone 470, the bottom-left corner zone 480, and the bottom-right corner zone 490. The APL and BL calculator circuit 646 may be further configured to select an appropriate normalization value from the received normalization values ​​depending on the type of the target zone and calculate a local APL for the target zone using the selected normalization value. For example, if the target zone is the interior zone 410, the APL and BL calculator circuit 646 may be configured to select a normalization value for the interior zone 410 and calculate a local APL for the target zone by dividing the filtered sum for the target zone by the selected normalization value. In another example, the APL and BL calculator circuit 646 may be further configured to, if the zone of interest is the top edge zone 420, select a normalization value for the top edge zone 420 and calculate the local APL for the zone of interest by dividing the filtered sum for the zone of interest by the selected normalization value, and similarly for other surrounding zones.

[0096] The APL and BL calculator circuit 646 is further configured to calculate a base backlight value for each light source 505 based on the local APL of the corresponding zone of that light source 505. In one implementation, the base backlight value for each light source 505 may increase as the local APL of the corresponding zone of that light source 505 increases. The calculated base backlight value for each light source 505 is provided to a backlight value generation circuit 650 (shown in FIG. 8 ) and used to determine a backlight value for that light source 505 and control the brightness level of that light source 505.

[0097] 13 is a flowchart of an exemplary process for local dimming, according to one or more embodiments. Process 1300 may be performed by display device 1000, and in particular by display driver 600 shown in FIG. 5. However, it will be understood that display devices having additional components and / or fewer components than those shown in FIG. 5 may be used to perform process 1300, that any of the steps described below may be performed in any suitable order, and that process 1300 may be performed in any suitable environment.

[0098] In step 1302, a backlight device (e.g., backlight device 500 shown in FIG. 5) including an array of light sources (e.g., light source 505) illuminates a display area (e.g., display area 310 shown in FIG. 4A and display area 405 shown in FIGS. 6 and 7A-7D) of a display panel (e.g., display panel 400). The display area is divided into a plurality of zones, each corresponding to a light source. The multiple zones include inner zones (e.g., inner zone 312 shown in FIG. 4A and inner zone 410 shown in FIGS. 7A-7D) corresponding to the inner light sources of the array of light sources (e.g., light source 322 shown in FIG. 4A and light source 505 in FIGS. 7A-7D), and outermost zones (e.g., outermost zones 334, 337, and 338 shown in FIG. 4A and outermost zones 420, 430, 440, 450, 460, 470, 480, and 490 shown in FIGS. 7A-7D) corresponding to the outermost light sources of the array of light sources (e.g., outermost light sources 324, 327, and 328 shown in FIG. 4A and outermost light sources 520, 530, 540, 550, 560, 570, 580, and 590 shown in FIGS. 7A-7D). The inner zones are located away from the edges of the display area of ​​the display panel, and each of the internal light sources is located at the center of each inner zone. The outermost zones are located along the edges of the display area of ​​the display panel, and each of the outermost zones differs in size or shape from at least one of the inner zones adjacent to the at least one outermost zone.

[0099] In step 1304, a display driver (for example, the display driver 600 shown in FIGS. 5 and 8) drives a plurality of pixels located in the display area based on the pixel data of the pixels in the display area.

[0100] In step 1306, the display driver controls the brightness level of a first outermost light source of the array of light sources based on first pixel data of a first pixel of the plurality of pixels, the first pixel being located in a first outermost zone of the outermost zones and the first outermost light source corresponding to the first outermost zone.

[0101] All references cited in this specification, including publications, patent applications, and patents, are incorporated by reference to the same extent as if each reference was individually and specifically indicated to be incorporated by reference, and are incorporated by reference in their entirety as if set forth herein.

[0102] The use of "a," "an," "the," "at least one," and similar reference words in the context of describing the present invention (particularly in the context of the claims below) should be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The use of a list of one or more items following the term "at least one" (e.g., "at least one of A and B") should be construed to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B), unless otherwise stated herein or clearly contradicted by context. The terms "comprising," "having," "including," and "including" should be construed as open-ended terms (i.e., meaning "including, but not limited to"), unless otherwise indicated. The recitation of ranges of values ​​herein, unless otherwise stated herein, is intended to serve merely as a shorthand method of referring individually to each individual value falling within the range, and each individual value is incorporated herein as if set forth individually herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or clearly contradicted by context. Any examples provided herein, or the use of exemplary language (e.g., "such as"), are intended merely to better illustrate the invention and do not limit the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0103] Exemplary embodiments are described herein. Variations of those exemplary embodiments will become apparent to those skilled in the art upon reading the foregoing description. The inventors expect that skilled artisans will adopt such variations as appropriate, and the inventors intend the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

Claims

1. a backlight device comprising an array of light sources configured to illuminate a display area of ​​the display panel; a driver circuit configured to drive a plurality of pixels of the display area; a backlight control circuit configured to control a luminance level of a first outermost light source of the array of light sources based on first pixel data of a first pixel of the plurality of pixels; Equipped with the display area is divided into a plurality of zones each corresponding to one of the light sources; The plurality of zones: an interior zone corresponding to an interior light source of the array of light sources; an outermost zone located along an edge of the display area of ​​the display panel and corresponding to the outermost light sources of the array of light sources; Including, the inner zone is located away from an edge of the display area of ​​the display panel; Each of the internal light sources is located at the center of a respective internal zone; each of the outermost zones differs in size or shape from at least one inner zone adjacent to the at least one outermost zone; the first pixel is located in a first outermost zone of the outermost zones, and the first outermost light source corresponds to the first outermost zone; Display device.

2. the first outermost zone is defined as an area where the extended zone and the display area of ​​the display panel overlap, the extended zone is defined so that the extended zone has the same size and shape as a first inner zone of the inner zones, and the first outermost light source is located at the center of the extended zone; the first inner zone is adjacent to the first outermost zone; The display device according to claim 1 .

3. The backlight control circuit further receiving an initialization value corresponding to a position of a corner of the first outermost zone in the extension zone; determining a filter coefficient for the first pixel located in the first outermost zone based on the initialization value; a filter coefficient determining section configured to apply the determined filter coefficient to the first pixel data of the first pixel located in the first outermost zone to generate filtered pixel data of the first pixel; controlling the luminance level of the first outermost light source based on the filtered pixel data of the first pixel; The display device according to claim 2 .

4. controlling the luminance level of the first outermost light source is further based on second pixel data of a second pixel of the plurality of pixels; the second pixel is located in an adjacent zone adjacent to the first outermost zone among the plurality of zones; The display device according to claim 2 .

5. The backlight control circuit further receiving an initialization value corresponding to a position of a corner of the first outermost zone in the extension zone; determining filter coefficients for the first pixel located in the first outermost zone and the second pixel located in the adjacent zone based on the initialization value; a filter configured to apply the determined filter coefficient to the first pixel data of the first pixel and the second pixel data of the second pixel to generate filtered pixel data of the first pixel and the second pixel; controlling the luminance level of the first outermost light source based on the filtered pixel data of the first pixel and the second pixel; The display device according to claim 4 .

6. the backlight control circuit is further configured to determine a sum of the filtered pixel data values ​​of the first pixel and the second pixel; The control of the brightness level of the first outermost light source is based on the sum of the values ​​of the filtered pixel data. The display device according to claim 5 .

7. The backlight control circuit further receiving a normalization value for the first outermost zone; a normalized sum is calculated by dividing the sum of the filtered pixel data values ​​by the normalization value; Controlling the luminance level of the first outermost light source is based on the normalized sum. The display device according to claim 6.

8. The initialization value corresponds to the sum of the filter coefficients determined for the first pixel and the second pixel. The display device according to claim 7 .

9. Each of the plurality of zones is substantially rectangular. The display device according to claim 1 .

10. The horizontal width of the first outermost zone is different from the horizontal width of the inner zone, and / or the vertical height of the first outermost zone is different from the vertical height of the inner zone. The display device according to claim 9 .

11. a driver circuit configured to drive a plurality of pixels of a display area of ​​a display panel, said display area being illuminated by a backlight device comprising an array of light sources; a backlight control circuit configured to control a luminance level of a first outermost light source of the array of light sources based on first pixel data of a first pixel of the plurality of pixels; Equipped with the display area is divided into a plurality of zones each corresponding to one of the light sources; The plurality of zones: an interior zone corresponding to an interior light source of the array of light sources; an outermost zone located along an edge of the display area of ​​the display panel and corresponding to the outermost light sources of the array of light sources; Including, the inner zone is located away from an edge of the display area of ​​the display panel; Each of the internal light sources is located at the center of a respective internal zone; each of the outermost zones differs in size or shape from at least one inner zone adjacent to the at least one outermost zone; the first pixel is located in a first outermost zone of the outermost zones, and the first outermost light source corresponds to the first outermost zone; Display driver.

12. the first outermost zone is defined as an area where an extension zone and the display area of ​​the display panel overlap, the extended zone is defined so that the extended zone has the same size and shape as a first inner zone of the inner zones, and the first outermost light source is located at the center of the extended zone; the first inner zone is adjacent to the first outermost zone; 12. A display driver according to claim 11.

13. The backlight control circuit further receiving an initialization value corresponding to a position of a corner of the first outermost zone in the extension zone; determining a filter coefficient for the first pixel located in the first outermost zone based on the initialization value; a filter coefficient determining section configured to apply the determined filter coefficient to the first pixel data of the first pixel located in the first outermost zone to generate filtered pixel data of the first pixel; controlling the luminance level of the first outermost light source based on the filtered pixel data of the first pixel; 13. A display driver according to claim 12.

14. Further, a storage device for storing the initialization value is provided.

14. A display driver according to claim 13.

15. controlling the luminance level of the first outermost light source is further based on second pixel data of a second pixel of the plurality of pixels; the second pixel is located in an adjacent zone adjacent to the first outermost zone among the plurality of zones; 13. A display driver according to claim 12.

16. The backlight control circuit further receiving an initialization value corresponding to a position of a corner of the first outermost zone in the extension zone; determining filter coefficients for the first pixel located in the first outermost zone and the second pixel located in the adjacent zone based on the initialization value; a filter configured to apply the determined filter coefficient to the first pixel data of the first pixel and the second pixel data of the second pixel to generate filtered pixel data of the first pixel and the second pixel; controlling the luminance level of the first outermost light source based on the filtered pixel data of the first pixel and the second pixel; 16. A display driver according to claim 15.

17. the backlight control circuit is further configured to determine a sum of the filtered pixel data values ​​of the first pixel and the second pixel; The control of the brightness level of the first outermost light source is based on the sum of the values ​​of the filtered pixel data.

17. A display driver according to claim 16.

18. The backlight control circuit further receiving a normalization value for the first outermost zone; a normalized sum is calculated by dividing the sum of the filtered pixel data values ​​by the normalization value; Controlling the luminance level of the first outermost light source is based on the normalized sum.

18. A display driver according to claim 17.

19. illuminating a display area of ​​a display panel with a backlight device comprising an array of light sources; driving a plurality of pixels of the display area; controlling a luminance level of a first outermost light source of the array of light sources based on first pixel data of a first pixel of the plurality of pixels; Including, the display area is divided into a plurality of zones each corresponding to one of the light sources; The plurality of zones: an interior zone corresponding to an interior light source of the array of light sources; an outermost zone located along an edge of the display area of ​​the display panel and corresponding to the outermost light sources of the array of light sources; Including, the inner zone is located away from an edge of the display area of ​​the display panel; Each of the internal light sources is located at the center of a respective internal zone; each of the outermost zones differs in size or shape from at least one inner zone adjacent to the at least one outermost zone; the first pixel is located in a first outermost zone of the outermost zones, and the first outermost light source corresponds to the first outermost zone; method.

20. the first outermost zone is defined as an area where the extended zone and the display area of ​​the display panel overlap, the extended zone is defined so that the extended zone has the same size and shape as a first inner zone of the inner zones, and the first outermost light source is located at the center of the extended zone; the first inner zone is adjacent to the first outermost zone; 20. The method of claim 19.

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