Backlight module, display device and backlight brightness adjusting method

Abstract

This invention discloses a backlight module, a display device, and a backlight brightness adjustment method. The backlight module includes at least two stacked light guide structures and a light-emitting structure. Each light guide structure has multiple light guide parts arranged in parallel. The side end face of each light guide part is set as the light incident surface, and the end face in the thickness direction is the light emitting surface. The light guiding directions of the light guide parts in different layers of the light guide structure are set at an angle. Each light guide part has multiple light guide points arranged in parallel along its light guiding direction. In the light emitting direction, the light guide points in each layer of the light guide structure are arranged in a one-to-one correspondence. The light-emitting structure includes multiple light-emitting parts, each of which is set corresponding to the light incident surface of one of the light guide parts. This solution achieves brightness zone control by superimposing the brightness of the light guide points in different light guide parts. By placing the light-emitting parts on the side of the light guide parts, the overall thickness of the backlight module is reduced, which can meet users' demand for thin television products.

Description

Technical Field

[0001] This invention relates to the field of display device technology, and in particular to a backlight module, a display device, and a backlight brightness adjustment method. Background Technology

[0002] MiniLED multi-zone backlighting has become a key component of high-end TVs, primarily because multi-zone backlighting control delivers higher dynamic contrast and better picture quality. MiniLED multi-zone backlighting typically uses a direct-lit backlight solution, meaning it achieves zone control through multiple LEDs behind the LCD screen. Since sufficient mixing distance is required between LEDs to ensure uniform backlight brightness and prevent dark areas, this mixing distance results in a larger overall thickness of the backlight module, which cannot meet users' demands for slim TVs. Summary of the Invention

[0003] The main objective of this invention is to propose a backlight module, a display device, and a backlight brightness adjustment method, aiming to solve the problem of the large thickness of the backlight module caused by the use of direct-lit backlighting in existing MiniLED multi-zone products.

[0004] To achieve the above objectives, the backlight module proposed in this invention includes:

[0005] The light guide structure comprises at least two stacked layers, each light guide structure having multiple light guide portions arranged in parallel. The side end face of each light guide portion is designated as the light incident surface, and the end face in the thickness direction is designated as the light emitting surface. The light guiding directions of the light guide portions in different layers of the light guide structure are arranged at an angle. Each light guide portion has multiple light guide points arranged in parallel along its light guiding direction. In the light emitting direction, the light guide points in each layer of the light guide structure are aligned one-to-one.

[0006] The light-emitting structure includes multiple light-emitting parts, each of which is disposed corresponding to the light-incident surface of one of the light-guiding parts.

[0007] Optionally, two light guide structures are provided, and the light guiding directions of the light guide parts in the two light guide structures are arranged perpendicularly.

[0008] Optionally, the light-emitting structure includes at least two light strips, and the at least two light strips are respectively disposed corresponding to at least two layers of the light guide structure;

[0009] The multiple light-emitting parts disposed on one of the light strips correspond to the multiple light guide parts disposed in the light guide structure of the same layer.

[0010] Optionally, the material of the light guide includes silicon dioxide; and / or,

[0011] The light guide structure includes a light guide plate.

[0012] Optionally, the light-emitting part includes an LED light.

[0013] Optionally, the brightness of the light-emitting part is adjustable and has multiple adjustment levels.

[0014] Optionally, a light-enhancing film is also provided in the light-emitting direction of the at least two light-guiding structures.

[0015] To achieve the above objectives, the display device proposed in this invention includes the backlight module described in any one of the above claims, wherein the backlight module includes:

[0016] The light guide structure comprises at least two stacked layers, each light guide structure having multiple light guide portions arranged in parallel. The side end face of each light guide portion is designated as the light incident surface, and the end face in the thickness direction is designated as the light emitting surface. The light guiding directions of the light guide portions in different layers of the light guide structure are arranged at an angle. Each light guide portion has multiple light guide points arranged in parallel along its light guiding direction. In the light emitting direction, the light guide points in each layer of the light guide structure are aligned one-to-one.

[0017] The light-emitting structure includes multiple light-emitting parts, each of which is disposed corresponding to the light-incident surface of one of the light-guiding parts.

[0018] To achieve the above objectives, the backlight brightness adjustment method proposed in this invention is based on the aforementioned display device, and the backlight brightness adjustment method includes the following steps:

[0019] Obtain the brightness distribution information of the current image, which includes the point coordinate parameters and point brightness parameters corresponding to multiple light guide points;

[0020] Based on the point coordinate parameters, the target light-emitting part is determined among the multiple light-emitting parts;

[0021] The required luminous power of the target luminous unit is determined based on the brightness parameters at the specified points.

[0022] The target light-emitting unit is controlled to operate at the required light-emitting power.

[0023] Optionally, the step of determining the required luminous power of the target light-emitting part based on the point brightness parameter includes:

[0024] The required brightness parameters of the target light-emitting part are determined based on the brightness parameters of the point and the brightness transmittance coefficient.

[0025] The required luminous power of the target light-emitting part is determined based on the required brightness parameter.

[0026] In the technical solution provided by this invention, in the light guide structure with at least two layers, since the light guide directions of each other are set at an angle, there are multiple intersecting light guide parts. Each light guide part forms a light guide point at the intersection point. When at least two light guide parts corresponding to the intersection point are illuminated by the light-emitting part, the brightness will be superimposed at the light guide point at the intersection point, thereby achieving the purpose of controlling the brightness of the corresponding zone. This backlight solution places the light-emitting part on the side of the light guide part, which only increases the space occupied by the backlight module on the side. However, since no light mixing distance is required, the overall thickness of the backlight module is greatly reduced, which can meet the user's demand for a slim TV product. At the same time, this solution uses a line light source composed of multiple light-emitting parts to replace the surface light source in the traditional direct-lit backlight solution, which greatly reduces the number of light-emitting parts used, reduces production costs, improves the overall heat generation, and improves the stability of the whole machine. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0028] Figure 1 An exploded structural diagram of an embodiment of the backlight module provided by the present invention;

[0029] Figure 2 for Figure 1 A schematic diagram of the planar structure of the light guiding structure and the light emitting structure in the image;

[0030] Figure 3 This is a flowchart illustrating an embodiment of the backlight brightness adjustment method provided by the present invention.

[0031] Explanation of icon numbers:

[0032] label name label name 100 Backlight module 113 Light guide point 1 Light guide structure 2 Light-emitting structure 1a Light guide plate 2a LED strip 11 Light guide section 21 Light-emitting part 111 Light-receiving surface 3 Brightness enhancement film 112 Light-emitting surface

[0033] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0035] It should be noted that if the embodiments of the present invention involve directional indication, the directional indication is only used to explain the relative positional relationship and movement of the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0036] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0037] MiniLED multi-zone backlighting has become a key component of high-end televisions, primarily because multi-zone backlighting control delivers higher dynamic contrast and better picture quality. MiniLED multi-zone backlighting typically employs a direct-lit backlight solution, meaning it uses multiple LEDs behind the LCD screen to achieve zone control. Since sufficient mixing distance is required between LEDs to ensure uniform backlight brightness and prevent dark areas, this mixing distance results in a relatively thick backlight module, which doesn't meet users' demands for slim televisions. Therefore, eliminating the mixing distance in the backlight module has become a crucial problem for those skilled in the art.

[0038] In view of this, the present invention proposes a backlight module, a display device, and a backlight brightness adjustment method, aiming to solve the problem of large backlight module thickness caused by the direct-lit backlight solution in existing MiniLED multi-zone products. Figure 1 An exploded structural diagram of an embodiment of the backlight module provided by the present invention; Figure 2 for Figure 1 A schematic diagram of the planar structure of the light guiding structure and the light emitting structure in the image; Figure 3 This is a flowchart illustrating an embodiment of the backlight brightness adjustment method provided by the present invention.

[0039] Please see Figures 1 to 2 The backlight module 100 includes at least two stacked light guide structures 1 and light-emitting structures 2. Each light guide structure 1 has a plurality of light guide parts 11 arranged in parallel. The side end face of each light guide part 11 is set as the light incident surface 111, and the end face in the thickness direction is the light emitting surface 112. The light guiding directions of the light guide parts 11 in different layers of the light guide structure 1 are set at an angle. Each light guide part 11 has a plurality of light guide points 113 arranged in parallel along its light guiding direction. In the light emitting direction, the light guide points 113 in each layer of the light guide structure 1 are arranged in a one-to-one alignment. The light-emitting structure 2 includes a plurality of light-emitting parts 21, and each light-emitting part 21 is respectively set corresponding to the light incident surface 111 of one of the light guide parts 11.

[0040] The structure of the light guide structure 1 can vary, as long as it includes multiple light guide parts 11 arranged side by side. These light guide parts 11 can be interconnected or separated; this embodiment does not limit this. Setting light guide points 113 on the light guide parts 11 means printing light guide points 113 on the bottom surface of the light guide parts 11 using laser engraving, V-shaped cross-grid engraving, or UV screen printing technology. The light guiding principle of the light guide parts 11 is as follows: light emitted from the light-emitting part 21 enters from the light-incident surface 111 of the light guide part 11 and propagates along the extension direction of the light guide part 11, which is the light guiding direction. When the light hits each light guide point 113, the reflected light diffuses at various angles, then breaks the reflection condition and exits along the light-emitting direction, which is the light-emitting surface 112 of the light guide part 11. The light guiding directions of the light guide parts 11 in different layers of the light guide structure 1 vary. The light guides are arranged at an angle, thus forming multiple intersection points. At each intersection point, multiple light guide points 113 are formed along the light emission direction and distributed in multiple light guide structures 1. Each light guide point 113 can be individually controlled to emit light, so as to emit mixed light at the corresponding intersection point. The function of the light-emitting part 21 is to provide light to the corresponding light guide part 11. This embodiment does not limit its specific structural type, but each light-emitting part 21 should be able to be individually controlled to emit light, so as to achieve independent control of the brightness of each light guide part 11. The light incident surfaces 111 of multiple light guide parts 11 in the same light guide structure 1 can be on the same side, or they can be distributed on different sides. Alternatively, light incident surfaces 111 can be provided on both sides of the light guiding direction of each light guide part 11. Multiple light guide parts 11 in the same layer are isolated from each other to avoid affecting the propagation of light.

[0041] In the technical solution provided by this invention, in the light guide structure 1 with at least two layers, since the light guide directions of each other are set at an angle, there are multiple light guide parts 11 arranged at intersections. Each light guide part 11 forms a light guide point 113 at the intersection point. When at least two light guide parts 11 corresponding to the intersection point are illuminated by the light-emitting part 21, the brightness will be superimposed at the light guide point 113 at the intersection point, thereby achieving the purpose of controlling the brightness of the corresponding zone. This backlight solution sets the light-emitting part 21 on the side of the light guide part 11, which only increases the space occupied on the side of the backlight module 100 by a small amount. However, since no light mixing distance is required, the overall thickness of the backlight module 100 is greatly reduced, which can meet the user's demand for a slim TV product. At the same time, this solution uses a line light source composed of multiple light-emitting parts 21 to replace the surface light source in the traditional direct-lit backlight solution, which greatly reduces the number of light-emitting parts 21 used, reduces production costs, improves the overall heat generation, and improves the stability of the whole machine.

[0042] The light guide structure 1 can be multi-layered or have only two layers. In the two-layered configuration, the light guiding directions of the two types of light guide parts 11 can be set at any angle, for example, 30° or 60°. Specifically, in this embodiment, two light guide structures 1 are provided, and the light guiding directions of the light guide parts 11 in the two light guide structures 1 are perpendicular. Using only two light guide structures 1 is sufficient to achieve superimposed control of zoned brightness, resulting in the lowest cost and the thinnest overall thickness of the two light guide structures 1. Simultaneously, the perpendicular orientation of the two light guide parts 11 allows the light guide points 113 to be arranged in an equally spaced array, resulting in a more uniform distribution, clearer division of each brightness zone, and better brightness control for multiple zones.

[0043] The light-emitting part 21 can be individually configured corresponding to the light guide part 11, or it can be connected to each other. Specifically, in this embodiment, the light-emitting structure 2 includes at least two light strips 2a, and the at least two light strips 2a are respectively configured corresponding to at least two layers of the light guide structure 1; wherein, multiple light-emitting parts 21 configured on one light strip 2a are respectively configured corresponding to multiple light guide parts 11 in the same layer of the light guide structure 1. By adopting the scheme of configuring the light strips 2a corresponding to the light guide structure 1, the installation process can be made more convenient, without the need to install each light-emitting part 21 individually. It should be explained that each light-emitting part 21 on the light strip 2a can also be controlled to emit light independently.

[0044] The light guide structure 1 can be composed of multiple independent light guide parts 11. However, this arrangement undoubtedly increases the difficulty of arranging multiple light guide parts 11 and makes it difficult to align the light guide points 113 of different layers as a whole. Therefore, in another embodiment, the light guide structure 1 includes a light guide plate 1a, and the light guide parts 11 are formed on the light guide plate 1a. By directly processing the light guide parts 11 on the light guide plate 1a, the difficulty of arranging multiple light guide parts 11 can be reduced. It is only necessary to control the alignment of at least two light guide plates 1a as a whole.

[0045] In this embodiment, the light guide 11 is made of silicon dioxide. By using high-purity silicon dioxide to make the light guide 11, it is possible to ensure that light undergoes total internal reflection, thereby ensuring the ability of light to propagate in a straight line.

[0046] It should be noted that the two parallel technical solutions mentioned above, "the material of the light guide part 11 includes silicon dioxide" and "the light guide structure 1 includes a light guide plate 1a", can be set individually or simultaneously. Obviously, setting them simultaneously is more effective.

[0047] There are various ways to form the light guide portion 11 on the light guide plate 1a. In some embodiments, multiple isolation layers extending along the light guiding direction are formed on the light guide plate 1a, and the light guide portion 11 is defined between two adjacent isolation layers. The isolation layers are formed by laser etching to isolate two adjacent light guide portions 11. In other embodiments, the light guide plate 1a includes a substrate and multiple inner cores. Multiple light guiding channels are formed in the substrate, and the multiple inner cores are respectively filled and disposed in the corresponding light guiding channels. Each inner core includes the light guide portion 11. The substrate is made of plexiglass, and the inner cores are made of silicon dioxide. By using high-purity silicon dioxide, light can undergo total internal reflection in the inner core, thereby ensuring the straight-line propagation capability of light. At the same time, since plexiglass has better impact resistance, housing the inner core in the substrate can improve the light guiding capability of the light guide plate 1a while ensuring the overall impact resistance and making it less prone to breakage.

[0048] The type of the light-emitting part 21 can be various, as long as it can emit light independently under control. Specifically, in this embodiment, the light-emitting part 21 includes an LED lamp. The LED lamp is used as a light source. Its spectrum contains no ultraviolet or infrared rays, so the lighting effect is green and environmentally friendly. At the same time, as a solid-state cold light source, the LED lamp generates less heat and has a longer service life.

[0049] In this embodiment, the brightness of the light-emitting part 21 is adjustable and has multiple adjustment levels. By setting the brightness of the light-emitting part 21 to be adjustable and having multiple adjustment levels, the light-emitting part 21 is given a dimming function, thereby enabling more delicate control of the light output, resulting in more obvious details in the brightness and darkness of the image and better image quality.

[0050] Specifically, the brightness of the light-emitting part 21 is controlled by 8-bit PWM, that is, 00 to FF corresponds to a brightness duty cycle of 0 to 100%, thereby realizing the graded brightness display of the LED. By graded control of the corresponding light-emitting parts 21 of each layer, the real-time brightness display can be guaranteed.

[0051] Taking the two-layer light guide structure 1 as an example, with 8-bit 255-level brightness level control, the light-emitting parts 21 of the first and second layers both have 255 levels of dimming function. Then, in the corresponding light guide point 113, the brightness adjustment capability of 255×255=65025 levels can be achieved, and the brightness control of the screen is more delicate than the traditional method.

[0052] A brightness enhancement plate 3 is also provided in the light-emitting direction of the at least two light-guiding structures 1. By providing the brightness enhancement plate 3, the light beam emitted through the light-emitting surface 112 can be concentrated in the normal direction, thereby improving the brightness.

[0053] Furthermore, to achieve the above objectives, the present invention also provides a display device, which includes the backlight module 100 described in the above technical solution. It should be noted that the detailed structure of the backlight module 100 of the display device can be referred to the embodiments of the backlight module 100 described above, and will not be repeated here. Since the backlight module 100 is used in the display device of the present invention, the embodiments of the display device of the present invention include all the technical solutions of all embodiments of the backlight module 100, and the achieved technical effects are completely the same, and will not be repeated here. The display device includes, but is not limited to, televisions, computer monitors, advertising screens, etc.

[0054] Furthermore, to achieve the above objectives, the present invention also provides a backlight brightness adjustment method based on a display device, wherein the display device includes the backlight module 100 described in the above technical solution, and the backlight brightness adjustment method includes the following steps:

[0055] S10. Obtain the brightness distribution information of the current image, the brightness distribution information including the point coordinate parameters and point brightness parameters corresponding to multiple light guide points 113;

[0056] The current image of the display device includes various information, including color distribution information and brightness distribution information. The color distribution information is used to control the display screen of the display device to display colors, while the brightness distribution information is used to control the backlight module 100 to provide a white light source. The brightness distribution information includes point coordinate parameters and point brightness parameters corresponding to multiple light guide points 113. The intensity of the white light to be emitted at the corresponding light guide point 113 can be accurately determined by the point coordinate parameters and the point brightness parameters.

[0057] S20. Based on the point coordinate parameters, determine the target light-emitting part 21 among the plurality of light-emitting parts 21;

[0058] The point coordinate parameters generally include coordinate values ​​of at least two different axes. The position of each coordinate value represents the number of layers of the light guide structure 1, and the specific value of the coordinate value represents one of the light guide parts 11 of the corresponding light guide structure 1. That is, the target light-emitting part 21 can be determined according to the point coordinate parameters.

[0059] S30. Determine the required luminous power of the target light-emitting part 21 based on the brightness parameters of the point;

[0060] The point brightness parameter is the required luminous intensity at the corresponding light guide point 113. Due to the alignment of each layer of light guide points 113, the required luminous intensity is actually the sum of the luminous intensities at each layer of light guide points 113. Each light guide point 113 corresponds to a corresponding light-emitting part 21. The luminous power of each light-emitting part 21 is related to the luminous intensity at the corresponding light guide point 113. The power distribution of each target light-emitting part 21 can be adaptively adjusted according to the point brightness parameters of other associated light guide points 113, as long as the luminous intensity of each target light-emitting part 21 after being superimposed at the light guide point 113 reaches the required luminous intensity.

[0061] S40. Control the target light-emitting unit 21 to operate at the required light-emitting power.

[0062] Each of the target light-emitting parts 21 operates with the required light-emitting power allocated to itself, thereby superimposing the corresponding light-emitting intensity at the light guide point 113.

[0063] In the above embodiment, the target light-emitting part 21 can be determined by the point coordinate parameters, and the required light-emitting power of each target light-emitting part 21 can be determined by the point brightness parameters. By controlling the corresponding target light-emitting part 21 to work at the required light-emitting power, the required light intensity can be superimposed at the corresponding light guide point 113, thereby realizing the display of light brightness corresponding to the current image.

[0064] Since the light emitted through the light guide structure 1 also needs to pass through structures such as the brightness enhancement film 3 and the diffusing film, each layer of the structure will cause a certain degree of light loss. Therefore, in this embodiment, the step of determining the required luminous power of the target light-emitting part 21 based on the point brightness parameter includes:

[0065] The required brightness parameters of the target light-emitting part 21 are determined based on the point brightness parameters and the brightness transmittance coefficient.

[0066] The brightness transmittance coefficient is derived from the actual light transmittance of the backlight module 100 to reflect the light loss rate of the backlight module 100. Taking the brightness transmittance coefficient into account can obtain a more accurate required brightness parameter, thereby guiding each of the target light-emitting parts 21 to emit light accordingly.

[0067] The required luminous power of the target light-emitting unit 21 is determined based on the required brightness parameter.

[0068] The required luminous power determined according to the required brightness parameter takes light loss into account, so that the light emitted by the target light-emitting part 21 is finally superimposed and emitted from the backlight module 100, which is closer to the brightness required by the current image.

[0069] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made under the concept of the present invention using the description and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A backlight module, characterized in that, include: The light guide structure comprises at least two stacked layers, each light guide structure having multiple light guide portions arranged in parallel. The side end face of each light guide portion is designated as the light incident surface, and the end face in the thickness direction is designated as the light emitting surface. The light guiding directions of the light guide portions in different layers of the light guide structure are arranged at an angle. Each light guide portion has multiple light guide points arranged in parallel along its light guiding direction. In the light emitting direction, the light guide points in each layer of the light guide structure are aligned one-to-one. The light-emitting structure includes multiple light-emitting parts, each of which is disposed corresponding to the light-incident surface of one of the light-guiding parts; The light guide structure includes a light guide plate; The light guide plate includes a substrate and multiple inner cores. Multiple light guide channels are formed in the substrate, and the multiple inner cores are respectively filled and disposed in the corresponding light guide channels. Each inner core includes a light guide portion. The substrate is made of plexiglass, and the inner cores are made of silicon dioxide.

2. The backlight module as described in claim 1, characterized in that, Two light guide structures are provided, and the light guiding directions of the light guide parts in the two light guide structures are arranged perpendicularly.

3. The backlight module as described in claim 1, characterized in that, The light-emitting structure includes at least two light strips, and the at least two light strips are respectively arranged corresponding to at least two layers of the light guide structure; The multiple light-emitting parts disposed on one of the light strips correspond to the multiple light guide parts disposed in the light guide structure of the same layer.

4. The backlight module as described in claim 1, characterized in that, The light-emitting part includes an LED light.

5. The backlight module as described in claim 1, characterized in that, The brightness of the light-emitting part is adjustable and has multiple adjustment levels.

6. The backlight module as described in claim 1, characterized in that, Brightness enhancement plates are also provided in the light-emitting directions of the at least two light-guiding structures.

7. A display device, characterized in that, Includes the backlight module as described in any one of claims 1 to 6.

8. A backlight brightness adjustment method based on the display device as described in claim 7, characterized in that, Includes the following steps: Obtain the brightness distribution information of the current image, which includes the point coordinate parameters and point brightness parameters corresponding to multiple light guide points; Based on the point coordinate parameters, the target light-emitting part is determined among the multiple light-emitting parts; The required luminous power of the target luminous unit is determined based on the brightness parameters at the specified points. The target light-emitting unit is controlled to operate at the required light-emitting power.

9. The backlight brightness adjustment method as described in claim 8, characterized in that, The step of determining the required luminous power of the target luminous part based on the point brightness parameters includes: The required brightness parameters of the target light-emitting part are determined based on the brightness parameters of the point and the brightness transmittance coefficient. The required luminous power of the target light-emitting part is determined based on the required brightness parameter.

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