Uniformly-spliced Mini LED backlight source module

Abstract

The utility model discloses a uniformly spliced Mini LED backlight source module which comprises more than two PCBs, each PCB comprises a plurality of LED chips, a packaging layer covering the LED chips and a reflecting layer covering the area except the LED chips and the packaging layer; wherein the packaging layer comprises a first packaging layer and a second packaging layer, the first packaging layer and the second packaging layer are of convex structures, and the first packaging layer covers the LED chip located on the outermost edge of the PCB. Through the structure of the packaging layer, the light-emitting angle of the Mini LED is increased, and the cost is reduced. Meanwhile, on the premise that the number of the Mini LEDs is reduced, the problem that the splicing position of the Mini LEDs is dark is effectively solved through matching of the two different packaging layer structures, and the effect that the light color of the spliced Mini LED backlight module is uniform is achieved.

Description

Technical Field

[0001] This utility model belongs to the field of LED display technology, specifically relating to a uniformly spliced ​​Mini LED backlight module. Background Technology

[0002] Mini LED backlight technology with dynamic dimming offers advantages such as high contrast and excellent display quality, and its market share is gradually increasing. Color gamut is a crucial indicator of display performance, including standards like NTSC and DCI-P3. Mini LED displays often employ blue LED chips combined with quantum dot films to achieve ultra-high color gamut. However, the high cost of Mini LED displays, especially with a large number of LED zones, significantly increases costs, further hindering their market penetration. Increasing the angle of the Mini LEDs, while maintaining uniformity, can effectively reduce the number of Mini LEDs and thus lower costs.

[0003] Mini LED backlight modules for LCD displays are currently mostly assembled from multiple small module boards due to limitations in manufacturing process and precision. However, due to various reasons (such as warping and gaps), the brightness at the splicing points is often darker than other parts of the module, resulting in uneven backlighting across the entire module. Solving the problem of dark areas at Mini LED splicing points and achieving a uniformly spliced ​​Mini LED backlight module while reducing the number of Mini LEDs is a pressing issue that needs to be addressed. Utility Model Content

[0004] In order to overcome the above-mentioned shortcomings of the prior art, the purpose of this utility model is to provide a uniformly spliced ​​MiniLED backlight module. Through the structure of the encapsulation layer, the darkness at the splicing point of the Mini LED is effectively improved, and a uniform light color effect is obtained.

[0005] To achieve its purpose, the technical solution adopted by this utility model is as follows:

[0006] A uniformly spliced ​​Mini LED backlight module includes two or more PCBs, each of the PCBs containing multiple LED chips, an encapsulation layer covering the LED chips, and a reflective layer covering the area excluding the LED chips and the encapsulation layer.

[0007] The encapsulation layer includes a first encapsulation layer and a second encapsulation layer. The first encapsulation layer and the second encapsulation layer have a convex structure. The first encapsulation layer covers the LED chip located at the outermost edge of the PCB.

[0008] Preferably, the two sides of the first encapsulation layer are symmetrically arranged with the center of the first encapsulation layer as the center line;

[0009] The side surface of the first encapsulation layer includes several continuously connected curves, and at least a portion of the curves on the side surface of the first encapsulation layer are arc-shaped.

[0010] The contact point between the outermost edge of the first encapsulation layer and the PCB is set as the starting point D1. The curves on the side of the first encapsulation layer include a first curve, a second curve, and a third curve. The starting end of the first curve overlaps with the starting point D1, and the second curve is located between the first curve and the third curve.

[0011] The termination point of the first curve is set as end point D2, the termination point of the second curve is set as end point D3, the angle formed by the line connecting the starting point D1 to the end point D2 and the PCB surface is set as θ1, the angle formed by the line connecting the end point D2 to the end point D3 and the PCB surface is set as θ2, the third curve is a partial arc from the end point D3 to the center of the first encapsulation layer, and the angle formed by the starting point of the third curve and the PCB surface is θ3. The angles are: θ3 > θ2 > θ1.

[0012] Preferably, the second encapsulation layer has a near-circular shape when viewed from above, and the cross-section of the second encapsulation layer includes two symmetrically arranged basic units, the side of which includes several continuously connected curves.

[0013] The curves on the side of the basic unit include a fourth curve, a fifth curve, and a sixth curve. The fifth curve is located between the fourth curve and the sixth curve. The starting point of the fourth curve is the contact point between the outermost edge of the second encapsulation layer and the PCB. The ending point of the sixth curve is the center point of the top surface of the second encapsulation layer.

[0014] The angle between the fourth curve and the PCB is between 35° and 70°.

[0015] The angle between the straight line formed by adjacent points within the fifth curve and the PCB decreases from the direction toward the center point of the top surface of the second encapsulation layer.

[0016] The angle between the starting point of the fourth curve and the adjacent point of the fifth curve is between 80° and 110°. The angle between the straight line formed by the starting point of the fifth curve and the nearest point of the adjacent sixth curve and the PCB is between -5° and 5°. The sixth curve is parallel to the PCB or forms an angle between -5° and 5°.

[0017] Preferably, the light-emitting surface of the LED chip is further provided with at least one Brass reflective layer.

[0018] Preferably, the intensity of the LED chip refracted to the reflective layer through the first encapsulation layer is less than the intensity refracted to the reflective layer through the second encapsulation layer.

[0019] Preferably, the ratio of the side height of the first encapsulation layer to the widest point of the first encapsulation layer is 0.25-0.33.

[0020] Preferably, the ratio of the side height of the second encapsulation layer to the widest point of the second encapsulation layer is 0.27-0.35.

[0021] Preferably, the encapsulation layer material is composed of one or more of silicone rubber, silicone resin, and epoxy resin.

[0022] Preferably, the reflective layer has a reflectivity of ≥80% for the LED chip.

[0023] Preferably, it also includes a fluorescent conversion film.

[0024] Compared with the prior art, the beneficial effects of this utility model are:

[0025] This invention proposes a uniformly spliced ​​Mini LED backlight module. Through the structure of the encapsulation layer, the light-emitting angle of the Mini LEDs is increased, reducing costs. Simultaneously, while reducing the number of Mini LEDs, the combination of two different encapsulation layer structures effectively improves the darkening problem at the Mini LED splicing points, achieving a uniform light color effect in the spliced ​​Mini LED backlight module. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a top view of the single Mini LED backlight module of this utility model;

[0028] Figure 2 This is a side view of the splicing Mini LED backlight module of this utility model;

[0029] Figure 3 This is a side view of the first encapsulation layer of this utility model;

[0030] Figure 4 This is a side view of the second encapsulation layer of this utility model;

[0031] Figure 5This is a top view of the splicing Mini LED backlight module of this utility model;

[0032] Figure 6 This is a top view of another splicing Mini LED backlight module of this utility model;

[0033] Figure 7 This is a schematic diagram showing the luminous angle and relative intensity of the first and second encapsulation layers of the Mini LED backlight module of this utility model.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1. PCB; 2. LED chip; 3. First encapsulation layer; 4. Second encapsulation layer; 5. Reflective layer; 6. Fluorescent conversion film. Detailed Implementation

[0036] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features of this utility model can be combined with each other. Many specific details are set forth in the following description to provide a thorough understanding of this utility model; the described embodiments are only a part of the embodiments of this utility model, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0038] Example 1

[0039] like Figures 1-5 As shown, this embodiment provides a Mini LED backlight module, comprising four PCBs 1, each PCB 1 containing multiple LED chips 2 arranged in a square matrix, an encapsulation layer covering the LED chips 2, and a reflective layer 5 covering the area excluding the encapsulation layer on the LED chips 2 and the area outside the encapsulation layer. The encapsulation layer comprises at least two structures: a first encapsulation layer 3 located on the outermost edge of the LED chips 2 of the PCB 1, and a second encapsulation layer 4 having a second encapsulation structure. Both the first encapsulation layer 3 and the second encapsulation layer 4 are convex structures, but their structures differ.

[0040] The two sides of the first encapsulation layer 3 are symmetrically arranged with the center of the first encapsulation layer as the center line. The side of the first encapsulation layer 3 includes several continuously connected curves. At least a part of the curves on the side of the first encapsulation layer are arc-shaped. The contact point between the outermost edge of the first encapsulation layer and the PCB is set as the starting point D1. The curves on the side of the first encapsulation layer include a first curve, a second curve and a third curve. The starting end of the first curve overlaps with the starting point D1. The second curve is located between the first curve and the third curve.

[0041] The termination point of the first curve is set as the end point D2, the termination point of the second curve is set as the end point D3, the angle formed by the line connecting the start point D1 to the end point D2 and the PCB surface is set as θ1, the angle formed by the line connecting the end point D2 to the end point D3 and the PCB surface is set as θ2, the third curve is a partial arc from the end point D3 to the center of the first encapsulation layer, and the angle formed by the start point of the third curve and the PCB surface is θ3. The magnitudes of the above angles are: θ3 > θ2 > θ1.

[0042] The second encapsulation layer 4 has a near-circular shape when viewed from above. Its cross-section consists of two nearly symmetrical basic units, each with several continuously connected curves on its side. These curves include a fourth, fifth, and sixth curve. The fifth curve is located between the first and third curves. The starting point of the fourth curve is the contact point between the outermost edge of the second encapsulation layer and the PCB. The ending point of the sixth curve is the center point of the top surface of the second encapsulation layer. The angle between the fourth curve and the PCB is between 35° and 70°. The angle between the straight line formed by adjacent points within the fifth curve and the PCB decreases from the direction towards the center point of the top surface of the second encapsulation layer. The angle between the starting point of the fourth curve and adjacent points of the fifth curve is between 80° and 110°. The angle between the straight line formed by the starting point of the fifth curve and the nearest point of the adjacent sixth curve and the PCB is between -5° and 5°. The sixth curve is parallel to the PCB or forms an angle between -5° and 5°.

[0043] In this embodiment, the light-emitting surface of the LED chip 2 is provided with 10 layers of Brass reflective layers. The intensity of the LED chip 2 refracted through the first encapsulation layer 3 to the reflective layer is less than the intensity refracted through the second encapsulation layer 4 to the reflective layer. The ratio of the side height of the first encapsulation layer 3 to its widest point is 0.25. The ratio of the side height of the second encapsulation layer 4 to its widest point is 0.3. The materials of the first encapsulation layer 3 and the second encapsulation layer 4 are composed of silicone rubber, both of which are the same material with a refractive index of 1.47. The reflective layer 5 has a reflectivity of 85% for the LED chip 2. In this embodiment, the LED chip 2 is blue with a peak wavelength of 445nm and also includes a phosphor conversion film 6. The phosphor conversion film forms a phosphor conversion layer, which absorbs part of the blue light emitted by the LED chip 2 and emits green and red light, which mix to form white light. In this embodiment, the material of the phosphor conversion layer includes green quantum dots that emit green light and red quantum dots that emit red light.

[0044] Example 2

[0045] like Figure 6 As shown, this utility model provides a Mini LED backlight module, which differs from Embodiment 1 in that it includes eight PCBs 1, each PCB 1 containing multiple LED chips 2, which are arranged in a diamond shape. The ratio of the side height of the first encapsulation layer 3 to the widest point of the first encapsulation layer is 0.29. The first encapsulation layer 3 is composed of silicone rubber with a refractive index of 1.41.

[0046] The ratio of the side height to the widest point of the second encapsulation layer 4 is 0.35. The second encapsulation layer appears circular when viewed from above. The cross-section of the second encapsulation layer includes two symmetrically arranged basic units. The side of each basic unit includes several continuously connected curves. The curves on the side of each basic unit include a fourth curve, a fifth curve, and a sixth curve. The fifth curve is located between the first curve and the third curve. The starting point of the fourth curve is the contact point between the outermost edge of the second encapsulation layer and the PCB, designated as D4. The ending point of the sixth curve is the center point of the top surface of the second encapsulation layer, designated as D7. The angle between the fourth curve and the PCB is 70°. The angle between the starting point of the fourth curve and the adjacent point of the fifth curve is 110°. The starting point of the fifth curve is D5. The straight line formed by the fifth curve and the nearest point of the adjacent sixth curve makes an angle of 5° with the PCB. The starting point of the sixth curve is D6. The sixth curve is parallel to the PCB or forms an angle of 5°.

[0047] The second encapsulation layer 4 is made of silicone resin with a refractive index of 4.8. In this embodiment, the light-emitting surface of the LED chip is provided with 10 layers of Brass reflective layers. In this embodiment, the reflective layer 5 has a reflectivity of 80% for the LED chip 2. In this embodiment, a fluorescence conversion film is also included, forming a fluorescence conversion layer. The fluorescence conversion layer is made of a nitride green powder that emits green light and a K2SiF6:Mn powder that emits red light. 4+ Fluorescent powder.

[0048] Example 3

[0049] This invention provides a Mini LED backlight module, which differs from Embodiment 1 in that the ratio of the side height to the widest point of the first encapsulation layer 3 is 0.33. The first encapsulation layer 3 is composed of a mixture of silicone rubber and silicone resin, and its refractive index is 1.52. In this embodiment, the first encapsulation layer 3 also contains diffused SiO2 particles.

[0050] The ratio of the side height to the widest point of the second encapsulation layer 4 is 0.27. The second encapsulation layer has a near-circular shape when viewed from above. The cross-section of the second encapsulation layer includes two symmetrically arranged basic units. The sides of each basic unit include several continuously connected curves. These curves include a fourth, fifth, and sixth curve. The fifth curve is located between the first and third curves. The starting point of the fourth curve is the contact point between the outermost edge of the second encapsulation layer and the PCB. The ending point of the sixth curve is the center point of the top surface of the second encapsulation layer. The angle between the fourth curve of the second encapsulation layer 4 and the PCB is 35°. The angle between the straight line formed by adjacent points within the fifth curve and the PCB decreases from the direction towards the center point of the top surface of the second encapsulation layer. The angle between the starting point of the fourth curve and the adjacent point of the fifth curve is 80°. The angle between the straight line formed by the starting point of the fifth curve and the nearest point of the adjacent sixth curve and the PCB is -5°. The sixth curve is parallel to the PCB or forms a 0° angle. The first encapsulation layer 3 is composed of silicone rubber with a refractive index of 1.5. In this embodiment, the second encapsulation layer 4 also contains diffused ZrO2 particles.

[0051] Due to various reasons (such as warping and gaps), the brightness at the splicing point is sometimes darker than other parts of the module, resulting in uneven backlighting across the entire module. This application addresses this issue by using two different encapsulation layers at different locations on the PCB (an outer ring and two different inner encapsulation layers) to achieve uniformity. The corresponding structure is as described in embodiments 1-3 above, where the structures of the first and second encapsulation layers determine the light-emitting effect. Figure 7The second encapsulation layer has a lower center light intensity (around 0°), with a center light intensity / maximum light intensity ratio between 0.1 and 0.3. The first encapsulation layer has a center light intensity / maximum light intensity ratio between 0.3 and 0.5. Due to the relatively lower center intensity of the second encapsulation layer, more light is refracted / reflected onto the PCB, resulting in a noticeable dark band at the junction. The edge of the first encapsulation layer receives less light than the second encapsulation layer, and this increased light compensates for the aforementioned dark band, thus achieving uniformity.

[0052] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Therefore, any modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. A Mini LED backlight module with uniform splicing, characterized in that, The PCB includes two or more PCBs, each of which comprises a plurality of LED chips, a packaging layer covering the LED chips, and a reflective layer covering areas other than the LED chips and the packaging layer. The packaging layer comprises a first packaging layer and a second packaging layer, and the first packaging layer and the second packaging layer are convex structures, and the first packaging layer covers the LED chips at the edge of the PCB.

2. The spliced uniform Mini LED backlight module according to claim 1, characterized in that, The two side surfaces of the first packaging layer are symmetrically arranged with the center of the first packaging layer as the center line. The side surface of the first packaging layer comprises a plurality of continuously connected curves, and at least a part of the curves of the side surface of the first packaging layer is in the shape of a circular arc. The contact point of the edge of the first packaging layer with the PCB is taken as the starting point D1, the curves of the side surface of the first packaging layer comprise a first curve, a second curve, and a third curve, the starting end of the first curve overlaps with the starting point D1, and the second curve is arranged between the first curve and the third curve. The terminal end of the first curve is taken as the end point D2, the terminal end of the second curve is taken as the end point D3, the included angle formed between the line connecting the starting point D1 and the end point D2 and the surface of the PCB is taken as θ1, the included angle formed between the line connecting the end point D2 and the end point D3 and the surface of the PCB is taken as θ2, the third curve is a part of a circular arc from the end point D3 to the center of the first packaging layer, and the angle formed between the starting end of the third curve and the surface of the PCB is θ3, and the above angles satisfy the following relationship: θ3> θ2> θ1.

3. The spliced uniform Mini LED backlight module of claim 1, wherein, The top view of the second packaging layer is in the shape of a circle, and the cross section of the second packaging layer comprises two symmetrically arranged basic units, and the side surface of the basic unit comprises a plurality of continuously connected curves. The curves of the side surface of the basic unit comprise a fourth curve, a fifth curve, and a sixth curve, the fifth curve is arranged between the fourth curve and the sixth curve, the starting end of the fourth curve is the contact point of the edge of the second packaging layer with the PCB, and the terminal end of the sixth curve is the center point of the top surface of the second packaging layer. The included angle between the fourth curve and the PCB is between 35° and 70°. The included angle between the straight line formed between the adjacent points in the fifth curve and the PCB decreases from the direction towards the center point of the top surface of the second packaging layer. The included angle between the starting end of the fourth curve and the adjacent point of the fifth curve is between 80° and 110°, the included angle between the straight line formed between the starting end of the fifth curve and the nearest point of the sixth curve and the PCB is between -5° and 5°, and the sixth curve is parallel to the PCB or forms an included angle of -5° to 5° with the PCB.

4. The spliced uniform Mini LED backlight module of claim 1, wherein, The light emitting surface of the LED chip is further provided with a Bragg reflection layer.

5. The spliced uniform Mini LED backlight module according to any one of claims 1-3, characterized in that, The intensity of the light refracted to the reflection layer through the first packaging layer is less than the intensity of the light refracted to the reflection layer through the second packaging layer.

6. The spliced uniform Mini LED backlight module of any one of claims 1-2, wherein, The ratio of the height of the side surface of the first packaging layer to the widest part of the first packaging layer is between 0.25 and 0.

33.

7. The spliced uniform Mini LED backlight module of any one of claims 1 or 3, wherein, The ratio of the side height of the second encapsulation layer to the widest part of the second encapsulation layer is 0.27-0.

35.

8. The spliced uniform Mini LED backlight module of claim 1, wherein, The encapsulation layer material is composed of one or more of silicone rubber, silicone resin, and epoxy resin.

9. The spliced uniform Mini LED backlight module of claim 1, wherein, The reflectivity of the reflective layer to the LED chip is ≥80%.

10. The spliced uniform Mini LED backlight module of claim 1, wherein, Further comprising a fluorescent conversion film.

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