A reflective cover applied to regional dimming and a backlight module

Abstract

The utility model relates to display technical field discloses a kind of reflector and backlight module applied to regional dimming, reflector includes multiple array type settings lamp cup, the lamp cup is formed by multiple cup surface of inclination setting, the top of the lamp cup is equipped with opening, the bottom of the lamp cup is equipped with lamp hole;The reflector is at least divided into outermost peripheral subarea and secondary peripheral subarea, and the at least two subareas exist difference on the area area occupied.By using the lamp cup structure of uniform inclination angle setting, the manufacturing and assembly complexity of reflector is simplified;In addition, by making lamp cup array form unequal spacing subarea in reflector, the illumination distribution ability of each area is adjusted using subarea area variation, the illumination weak area of edge area is better compensated, and the uniformity of whole screen brightness is improved.

Description

Technical Field

[0001] This utility model relates to the field of display technology, and in particular to a reflector and backlight module for local dimming. Background Technology

[0002] Local dimming is a display technology primarily used in LCD (Liquid Crystal Display) and LED-backlit TVs. It works by dividing the backlight area into multiple independent dimming zones, dynamically adjusting the brightness of each zone based on the content of the image. For example, when a part of the image is a dark scene, the corresponding backlight area will dim, while the bright scene areas will maintain or increase their brightness, thereby improving image contrast and black purity, making the display effect closer to that of a self-emissive screen.

[0003] With the development of Mini LED technology, local dimming has been widely used in high-end LCD display products. By introducing local dimming zones into the backlight module, it enhances high contrast and detail. Existing local dimming backlight module structures often use arrayed reflectors to separate and directionally reflect LED chips, thereby improving the stability and light control capability of light distribution within each zone.

[0004] However, in practical applications, differences in optical path distance and edge effects between the edges, corners, and center of the display screen can easily lead to uneven brightness distribution in the backlight area, such as excessive brightness in the center, dark edges, and dark spots at the corners, thus affecting the overall uniformity of the screen display. Therefore, improvements to existing technologies are necessary.

[0005] The above information is provided as background information only to aid in understanding this disclosure and does not constitute an assertion or admission that any of the above content can be used as prior art relative to this disclosure. Utility Model Content

[0006] This invention provides a reflector and backlight module for local dimming, in order to solve the problems existing in the prior art.

[0007] To achieve the above objectives, this utility model provides the following technical solution:

[0008] A reflector for local dimming includes multiple arrayed lamp cups, each lamp cup being formed by multiple inclined cup surfaces, each lamp cup having an opening at its top and a lamp hole at its bottom;

[0009] The reflector is divided into at least an outermost zone and a second outermost zone, and the at least two zones differ in the area they occupy.

[0010] Optionally, the tilt angle of the cup surface is 20-30°.

[0011] Optionally, the area of ​​the outermost partition accounts for 78%-83% of the total area of ​​the reflector; the area of ​​the second outermost partition accounts for 86%-91% of the total area of ​​the reflector.

[0012] Optionally, the cup surface is curved, and the curvature of the cup surface is 25-35°.

[0013] Optionally, the top opening of the lamp cup is square.

[0014] Optionally, the lamp cups located in the four corner areas of the reflector are 1 / 2 to 1 / 3 lower in height than those in the adjacent areas.

[0015] Optionally, the reflector is an injection-molded, one-piece structure.

[0016] Optionally, the inner surface of the cup surface is provided with raised dots or ridges to enhance reflection.

[0017] Optionally, the periphery of the lamp hole is provided with an expanded surface.

[0018] This utility model also provides a backlight module, including a reflector, LED beads and a substrate disposed above the reflector, and a diffuser plate disposed below the reflector;

[0019] The reflector is any of the reflectors described above for use in local dimming.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] This utility model provides a reflector and backlight module for regional dimming, which adopts a lamp cup structure with a uniform tilt angle, simplifying the manufacturing and assembly complexity of the reflector. In addition, by making the lamp cup array form unequal intervals in the reflector, the light distribution capability of each area is adjusted by the change of the area of ​​the interval, which better compensates for the weak light areas at the edge and improves the brightness uniformity of the whole screen.

[0022] This invention has other features and advantages that will be apparent from or will be set forth in detail in the accompanying drawings and the following detailed description, which together serve to explain the particular principles of this invention. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this utility model 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 this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of a reflector for use in local dimming provided by this utility model;

[0025] Figure 2 This is a cross-sectional view of a reflector for local dimming provided by this utility model at section line AA;

[0026] Figure 3 This is a schematic diagram of the structure of a lamp cup in a reflector used for local dimming, provided by this utility model.

[0027] Figure 4 This is a schematic diagram of a reflector for use in regional dimming provided by this utility model;

[0028] Figure 5 This is a schematic diagram of the parameters of a lamp cup in a reflector used for local dimming, provided by this utility model;

[0029] Figure 6 This utility model provides a curve of light uniformity of different cup surfaces under different inclinations in a reflector used for regional dimming;

[0030] Figure 7 This is a schematic diagram of an improved structure of a lamp cup in a reflector used for local dimming, provided by this utility model;

[0031] Figure 8 This is a schematic diagram of a reflector with protruding ridges on the cup surface for use in regional dimming, provided by this utility model;

[0032] Figure 9 This utility model provides a light uniformity curve diagram of different lamp cup structures in a reflector used for regional dimming;

[0033] Figure 10 This is another structural schematic diagram of a lamp cup in a reflector used for local dimming provided by this utility model;

[0034] Figure 11 This utility model provides a light uniformity curve corresponding to lamp surfaces of different curvatures in a reflector used for regional dimming.

[0035] Figure 12This utility model provides a curve of illumination uniformity under different outward emission angles in a reflector used for regional dimming.

[0036] Reference numerals: 100, reflector; 10, lamp cup; 11, top opening; 12, lamp hole; 13, cup surface; 14, reflector cavity structure; 15, outer expansion surface. Detailed Implementation

[0037] To illustrate the possible application scenarios, technical principles, implementable specific solutions, and achievable objectives and effects of this application in detail, the following description, in conjunction with the listed specific embodiments and accompanying drawings, provides a detailed explanation. The embodiments described herein are merely illustrative of the technical solutions of this application and are therefore intended to limit the scope of protection of this application.

[0038] In this document, the term "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The term "embodiment" appearing in various places throughout the specification does not necessarily refer to the same embodiment, nor does it specifically limit its independence or connection with other embodiments. In principle, in this application, as long as there are no technical contradictions or conflicts, the technical features mentioned in each embodiment can be combined in any way to form corresponding implementable technical solutions.

[0039] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the use of related terms herein is merely for the purpose of describing particular embodiments and is not intended to limit this application.

[0040] In the description of this application, the term "and / or" is used to describe the logical relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A exists, B exists, and A and B exist simultaneously. Additionally, the character " / " in this document generally indicates that the preceding and following objects have an "or" logical relationship.

[0041] In this application, terms such as “first” and “second” are used only to distinguish one entity or operation from another, and do not necessarily require or imply any actual quantity, hierarchy or order relationship between these entities or operations.

[0042] Unless otherwise specified, the use of terms such as “comprising,” “including,” “having,” or other similar expressions in this application is intended to cover non-exclusive inclusion, which does not exclude the presence of additional elements in a process, method, or product that includes the stated elements, such that a process, method, or product that includes a list of elements may include not only those defined elements but also other elements not expressly listed, or elements inherent to such a process, method, or product.

[0043] Similar to the understanding in the Examination Guidelines, in this application, expressions such as "greater than," "less than," and "exceeding" are understood to exclude the stated number; expressions such as "above," "below," and "within" are understood to include the stated number. Furthermore, in the description of the embodiments in this application, "multiple" means two or more (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups" and "multiple times," unless otherwise explicitly specified.

[0044] In the description of the embodiments of this application, the space-related expressions used, such as "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "vertical," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," indicate the orientation or positional relationship based on the orientation or positional relationship shown in the specific embodiments or drawings. They are only for the purpose of describing the specific embodiments of this application or for the reader's understanding, and do not indicate or imply that the device or component referred to must have a specific position, a specific orientation, or be constructed or operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0045] Unless otherwise expressly specified or limited, the terms "installation," "connection," "linking," "fixing," and "setting," as used in the description of the embodiments of this application, should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two components or the interaction between two components. For those skilled in the art to which this application pertains, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0046] To address the issues of insufficient brightness uniformity and significant differences in regional illumination distribution in existing Local Dimming backlight modules, this invention provides a reflector for Local Dimming backlight modules. By setting a fixed tilt angle in the reflector structure and dividing the lamp array into unequal regions, the area distribution of each region is differentiated, thereby optimizing the overall illumination uniformity.

[0047] Please refer to Figure 1 This is a schematic diagram of the structure of a reflector 100 for use in local dimming provided by the present invention. The reflector 100 includes a plurality of lamp cups 10 arranged in an array.

[0048] Please refer to the reference. Figure 2 , Figure 3 The figures shown are a cross-sectional view of a reflector 100 for local dimming provided by this utility model at section line AA, and a structural schematic diagram of the lamp cup 10. Each lamp cup 10 is formed by multiple inclined cup surfaces 13 surrounding a reflective cavity structure 14 with a top opening 11 and a lamp hole 12 at the bottom.

[0049] The lamp cups 10 are arranged in a regular manner with uniform opening shapes, which is conducive to achieving a one-to-one correspondence of Mini LED light sources.

[0050] Please refer to Figure 4 This diagram illustrates the partitioning of a reflector 100 for local dimming, as provided by this invention. The reflector 100 is divided into at least two partitions based on the arrangement of the lamp cups 10 within it. These two partitions differ in their area, specifically being an outermost partition and a second outermost partition. By dividing the lamp cup array into unequally spaced areas, the area distribution of each partition is differentiated, compensating for weak illumination areas at the edges and thus optimizing overall illumination uniformity.

[0051] Please refer to Figure 5 This is a schematic diagram showing the parameters of the lamp cup 10 in a reflector 100 for local dimming, provided by this utility model. α represents the emission angle of the lamp bead, h represents the height of the lamp cup 10, and β represents the tilt angle of the cup surface 13. Specifically, the tilt angle of the cup surface 13 of each lamp cup 10 remains consistent throughout the entire reflector 100, and the tilt angle of the cup surface 13 is 20-30°.

[0052] Understandably, the tilt angle of the cup surface 13 can also be 5°, 10°, 17.5°, 20°, 22.5°, 25°, 27.5°, or 30°. Testing showed that the highest brightness uniformity was obtained when the tilt angle of the cup surface 13 was set to 25°. Please refer to [the relevant documentation / reference]. Figure 6The graph shows the illumination uniformity curves for different cup surfaces 13 under different inclination angles. The graphs show that the illumination uniformity is optimal, reaching 55%, when the inclination angle of the cup surface 13 is set to 25°.

[0053] By uniformly setting the tilt angle, a stable light diffusion direction can be maintained throughout the entire area of ​​the reflector 100, reducing light defocusing or interference caused by angle differences and improving the uniformity and consistency of module brightness.

[0054] Furthermore, the reflector 100 is divided into an outermost zone and a second outermost zone, with differences in projected area and arrangement density between the two zones. The outermost zone accounts for 78% to 83% of the total area of ​​the reflector 100, while the second outermost zone accounts for 86% to 91%, thereby achieving an edge enhancement lighting effect.

[0055] By adjusting the area ratio of the zones, gradual control of regional illumination intensity can be achieved. The outermost zone has a relatively small area, making the light in the edge area denser, thus compensating for the problem of dark edges that easily occur in conventional structures; while the next outermost zone transitions to the central area, providing a buffer for overall light balance and ensuring that the center is not overexposed.

[0056] In this invention, the height of the lamp cup 10 is further optimized in the four corner areas of the reflector 100 to improve the supplementary lighting capability in the corner areas.

[0057] Furthermore, the height of the lamp cups 10 in the four corner areas is reduced by 1 / 2 or 1 / 3 compared to the adjacent areas.

[0058] Please refer to Table 1, which shows the actual improvement effect of the four-corner height reduction scheme on backlight uniformity in a comparison of 18 groups of samples. After testing the 18 groups of samples, it was verified that the height difference significantly improves the brightness of the four corners, alleviates the dark corner phenomenon, and helps to improve the brightness consistency of the four corners of the display screen.

[0059] Table 1

[0060]

[0061] It is understood that the height reduction design in this embodiment is equivalent to accelerating the optical path at the four corners, shortening the reflection path, and increasing the local light flux, which is suitable for large-size, multi-zone panel structures.

[0062] Furthermore, the top opening 11 of the lamp cup 10 is preferably square to accommodate the arrangement of Mini LED beads in a square array, while also being easy to process and shape.

[0063] like Figure 7 The diagram shown is a schematic representation of an improved structure of the lamp cup 10 in a reflector 100 for local dimming provided by this utility model. Figure 7 (a) is a traditional lamp cup 10 structure, Figure 7 (b) is an improved lamp cup structure of this utility model. By setting a concave guiding structure on the cup surface 13, the cup surface 13 is an overall concave reflective surface, so that the reflector 100 provided by this utility model has a structure that is different from conventional planar or conical reflectors. It can more concentratedly converge and guide the light emitted by the LED beads through the concave contour.

[0064] Understandably, the aforementioned concave design causes multiple diffuse reflections of light after it enters the cup cavity, thereby avoiding excessive light concentration or local hot spots in the central area. It is particularly suitable for large-angle diffused Mini LED packaging, which can effectively improve the uniformity of horizontal light output and expand the vertical light output angle to achieve a softer and more uniform backlight brightness distribution.

[0065] Furthermore, the concave structure provides an inwardly converging reflection channel for edge light, effectively reducing light leakage and improving light utilization. This results in significant edge contour control in zoned light control designs. The structure can be directly molded using injection molding, combining optical performance with manufacturing feasibility.

[0066] Furthermore, in order to enhance the light reflection efficiency inside the lamp cup 10, a microstructure unit is provided on the inner side of the cup surface 13, the microstructure unit including highly raised dots or raised ridges.

[0067] like Figure 8 As shown in the diagram, this utility model provides a structural schematic of a reflector 100 for use in local dimming, in which the cup surface 13 is provided with a protruding ridge. This protruding ridge can increase the number of reflection paths, in conjunction with, for example... Figure 9 The test results show that when the tilt angle of the cup surface 13 is 28° and it is combined with the convex edge, the structure can effectively improve the uniformity of light illumination, which can reach 52%.

[0068] The height of the microstructure unit can be selected from 0.1mm to 1mm. By changing the microscopic surface morphology, multiple reflection paths of light are increased, which effectively suppresses the phenomenon of direct light concentration and improves the scalability of the light output angle.

[0069] like Figure 10 As shown, furthermore, the cup surface 13 has an arc-shaped reflective structure, which forms a continuous concave arc along the radial direction, with the arc angle set at 25-35°. Please refer to... Figure 11 The figure shows the uniformity of illumination corresponding to different curvatures of the lamp surface. As can be seen from the figure, the uniformity of illumination is the best when the curvature of the lamp surface is 45°, reaching 53%.

[0070] Furthermore, the light emission angle of the lamp cup 10 is 25-35°. Please refer to [reference needed]. Figure 12To determine the illumination uniformity under different outward emission angles, the illumination uniformity of the lamp cup 10 is optimal when the emission angle of the lamp cup 10 is 30°, reaching 52%.

[0071] Furthermore, the lamp cup 10 has an outwardly inclined extended surface around the lamp hole 12 at the bottom, such as... Figure 8 As shown, the extended surface 15 is used to guide the light from the side-emitting area of ​​the LED lamp bead to be reflected upwards and converged to the reflection path of the cup surface 13.

[0072] Understandably, the curved cup surface 13 structure, combined with the outward expansion of the lamp hole 12, achieves a larger light output angle range. In actual tests, under the same power input, the brightness boundary of the light output area is soft and there are no obvious hot spots. The brightness deviation between the center and the edge is significantly reduced, making it suitable for Mini LED direct-lit backlight modules with high requirements for the uniformity of the partition boundary.

[0073] This utility model also provides a backlight module, including the reflector 100 as described above. The reflector 100 can be combined with multiple LED beads, diffuser plates and substrates to form a complete Local Dimming backlight module.

[0074] LED beads are mounted on a substrate, and a reflector 100 covers it. Each lamp cup 10 is installed in a one-to-one correspondence with each LED bead. A diffuser plate is located above the reflector 100, and the distance between the diffuser plate and the lamp cup 10 is set to 1.2 to 2 times the height of the lamp cup 10.

[0075] Through the above combination structure, after the light is reflected and shaped by the lamp cup 10, it forms multiple expansions and mixtures at the diffuser plate, achieving a backlight effect with uniform brightness within the zone and clear optical isolation between zones.

[0076] This structure is suitable for Mini LED direct-lit backlight systems. By controlling the light through current and physical structure, it meets the display technology requirements such as high contrast and high dynamic range.

[0077] The present invention will be further described below with reference to specific embodiments. It should be understood that the following embodiments are merely preferred embodiments of the present invention and do not limit the scope of protection of the present invention. All modifications, equivalent substitutions or improvements made under the substantial spirit and principles of the present invention should be covered within the scope of protection of the present invention.

[0078] Example 1

[0079] In this embodiment, the tilt angle of the cup surface 13 is 25°, and the lamp cup 10 formed is a quadrilateral structure with a square opening 11 at the top.

[0080] The unequal-spaced partitions of the reflector 100 are as follows: the outermost ring accounts for 78% of the area, and the next outermost ring accounts for 86%. When the outermost ring accounts for 78% of the area and the top opening 11 is square, the illumination uniformity can reach 56%.

[0081] The height of the lamp cups 10 in the four corner areas of the reflector 100 is reduced by 1 / 2 compared to the adjacent areas.

[0082] This combined structure has been proven through multiple tests to have significant advantages in terms of partition uniformity and improved corner brightness, making it suitable for display screen scenarios with high requirements for brightness consistency.

[0083] By reducing the density of lamp cups 10 per unit area in the edge region, the regional supplementary lighting capability is improved. Combined with the reduction of the height of the four corner lamp cups 10, the dark spots at the edges and corners are effectively alleviated, and the measured uniformity is significantly improved.

[0084] Example 2

[0085] In this embodiment, the tilt angle of the cup surface 13 is 25°, and the lamp cup 10 formed is a quadrilateral structure with a square opening 11 at the top.

[0086] The unequal-spaced partitions of the reflector 100 are as follows: the outermost partition accounts for 81.5% of the area, and the second outermost partition accounts for 89.5% of the area.

[0087] In this embodiment, all lamp cups 10 have the same height.

[0088] This solution provides a stable brightness distribution effect while maintaining structural manufacturing consistency, which facilitates the integrated injection molding process of the module.

[0089] This embodiment is adapted to Mini LED arrays and has good injection molding properties and structural consistency.

[0090] Example 3

[0091] In this embodiment, the tilt angle of the cup surface 13 is 25°, and the lamp cup 10 formed is a quadrilateral structure with a square opening 11 at the top.

[0092] The non-equidistant partitions of the reflector 100 are as follows: the outermost ring has an area of ​​78%. The height of the four corner lamp holders 10 is reduced by 1 / 3 compared to the surrounding lamp holders 10.

[0093] This structure is suitable for narrow-bezel modules with high requirements for corner brightness adjustment. By reducing the height to compensate for lighting defects, it helps to improve the user's viewing experience.

[0094] Example 4

[0095] In this embodiment, the tilt angle of the cup surface 13 is 25°, and the lamp cup 10 formed is a quadrilateral structure with a square opening 11 at the top.

[0096] The unequal-spaced partitions of the reflector 100 are as follows: the outermost partition has an area of ​​79.5%, and the second outermost partition has an area of ​​87.5%.

[0097] This embodiment achieves a balance between brightness uniformity, module assembly efficiency, and manufacturing process, and is suitable for display module products with a medium to high number of zones.

[0098] Finally, it should be noted that although the above embodiments have been described in the text and drawings of this application, this should not be construed as limiting the scope of protection of this application. Any technical solutions resulting from equivalent structural or procedural substitutions or modifications made based on the essential concept of this application and utilizing the content described in the text and drawings of this application, as well as the direct or indirect application of the technical solutions of the above embodiments to other related technical fields, are all included within the scope of protection of this application.

Claims

1. A reflector for use in local dimming, characterized in that: It includes multiple lamp cups arranged in an array, each lamp cup being formed by multiple inclined cup surfaces, each lamp cup having an opening at the top and a lamp hole at the bottom; The reflector is divided into at least an outermost zone and a second outermost zone, and at least the two zones differ in the area they occupy.

2. The reflector for local dimming according to claim 1, characterized in that, The tilt angle of the cup surface is 20-30°.

3. The reflector for local dimming according to claim 1, characterized in that, The outermost zone accounts for 78%-83% of the total area of ​​the reflector; the second outermost zone accounts for 86%-91% of the total area of ​​the reflector.

4. The reflector for local dimming according to claim 1, characterized in that, The cup surface is curved, and the curvature of the cup surface is 25-35°.

5. The reflector for local dimming according to claim 1, characterized in that, The top opening of the lamp cup is square.

6. The reflector for local dimming according to claim 1, characterized in that, The lamp cups located in the four corner areas of the reflector are 1 / 2 to 1 / 3 lower in height than those in the adjacent areas.

7. The reflector for local dimming according to claim 1, characterized in that, The reflector is a one-piece structure formed by injection molding.

8. The reflector for local dimming according to claim 1, characterized in that, The inner surface of the cup is provided with raised dots or ridges to enhance reflection.

9. The reflector for local dimming according to claim 1, characterized in that, The periphery of the lamp hole is provided with an outwardly expanded surface.

10. A backlight module, comprising a reflector, LED beads and a substrate disposed above the reflector, and a diffuser disposed below the reflector; The reflector is the reflector for use in local dimming as described in any one of claims 1 to 9.

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