Novel quantum dot LED light source and LED display screen
By directly covering the blue light chip with a uniform mixing of red light quantum dots, green light quantum dots and copolymers in the LED light source, the problems of cumbersome packaging and high light energy loss are solved, and more efficient light energy extraction and use.
Patent Information
- Application Number
- CN202420613576.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Priority Date
- 2024-02-09
- Filing Date
- 2024-03-27
- Publication Date
- 2025-02-07
- Estimated Expiration
- 2034-03-27
AI Technical Summary
The packaging process of traditional LED light sources is cumbersome and has high light energy loss, resulting in low efficiency.
A new quantum dot LED light source is adopted, which includes a bracket, a blue light chip and a casting layer. The casting layer is formed by uniformly mixing red light quantum dots, green light quantum dots and copolymers, directly covering the blue light chip to simplify the packaging process.
The packaging process is simplified, manufacturing costs are reduced, light reflection is reduced, and quantum efficiency and light extraction efficiency are improved.
Smart Images
Figure CN222442207U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of LED, in particular to a novel quantum dot LED light source and an LED display screen. Background Art
[0002] LED (light emitting diode) is a solid-state semiconductor element that can convert electrical energy into visible light. LED consists of two parts, one is a P-type semiconductor dominated by holes, and the other is an N-type semiconductor dominated by electrons, with a PN junction formed between the two interfaces. When current acts on the diode through a wire, electrons move to the P region and recombine with holes at the PN junction, and emit energy in the form of photons.
[0003] Quantum dots, also known as semiconductor fluorescent nanocrystals, have begun to attract widespread attention from LED product researchers due to their advantages such as high color purity, high quantum efficiency, wide color gamut, and adjustable emission wavelength. At present, when LED light sources use quantum dots instead of traditional phosphors, they are mainly packaged by quantum dot glue and resin casting blue light chips. The two colloids are cast in succession, and the later cast colloid must wait until the first cast colloid is solidified before it can be cast, which leads to a decrease in the packaging efficiency of the LED light source. At the same time, the two layers of different colloids will also cause light to reflect between the two layers of colloid materials, resulting in higher light energy loss. Utility Model Content
[0004] In order to solve the problems of complicated packaging and high light energy loss of traditional LED light sources, the utility model provides a novel quantum dot LED light source and LED display screen.
[0005] In order to solve the above technical problems, the utility model provides a novel quantum dot LED light source, which comprises a bracket, a blue light chip and a casting layer. The bracket is provided with an installation space for accommodating the blue light chip. The casting layer fills the installation space and covers the blue light chip. The casting layer comprises red light quantum dots, green light quantum dots and a copolymer, and the copolymer covers the red light quantum dots and the green light quantum dots.
[0006] In an embodiment of the utility model, the red light quantum dots and the green light quantum dots both adopt an alloy core-shell structure, the red light quantum dots have a luminescence peak range of 620nm-680nm, and the green light quantum dots have a luminescence peak range of 510nm-550nm.
[0007] In an embodiment of the utility model, the novel quantum dot LED light source further includes a substrate and a soldering pad, and the surface of the substrate is attached between the bracket and the soldering pad.
[0008] In an embodiment of the present utility model, the substrate is a metal alloy substrate or a ceramic substrate, the bracket is a metal alloy bracket or a ceramic bracket, and the substrate and the bracket are made of different materials.
[0009] In an embodiment of the utility model, a gold wire is arranged on the blue light chip, and the blue light chip is connected to the pad through the gold wire.
[0010] In an embodiment of the utility model, the blue light chip is a vertical structure chip, which includes a sapphire substrate, an n-GaN layer, a pn junction and a p-GaN layer from bottom to top, the n-GaN layer is connected to an n-type electrode, and the p-GaN layer is connected to a p-type electrode.
[0011] In an embodiment of the utility model, the novel quantum dot LED light source further comprises a die-bonding silicone glued and fixed between the bracket and the blue light chip.
[0012] In an embodiment of the utility model, the height of the casting layer filled in the installation space exceeds the height of the blue light chip and is flush with the upper end surface of the bracket.
[0013] In order to solve the above technical problems, the utility model also provides an LED display screen, characterized in that the LED display screen includes a backlight panel, a liquid crystal panel and the above-mentioned novel quantum dot LED light source, the novel quantum dot LED light source array is arranged on the backlight panel, and the liquid crystal panel covers the backlight panel.
[0014] In an embodiment of the utility model, the novel quantum dot LED light source array is arranged on the backlight panel in the manner of arranging the array on the back panel of the backlight panel and / or the array is arranged on the side panel of the backlight panel.
[0015] Compared with the prior art, the beneficial effects of the present invention are:
[0016] Through the technical solution of the utility model, red light quantum dots, green light quantum dots and copolymers are uniformly mixed to form a casting layer, and a layer of casting layer is used to encapsulate the blue light chip in the bracket, which simplifies the packaging process and reduces the manufacturing cost. In addition, there is no obvious difference in density at various positions in the mixed casting layer, which can reduce the reflection effect of light and greatly improve the quantum efficiency and light extraction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The accompanying drawings are used to provide a further understanding of the embodiments of the present utility model and constitute a part of the specification. Together with the following specific implementation methods, they are used to explain the embodiments of the present utility model, but do not constitute a limitation on the embodiments of the present utility model. In the accompanying drawings:
[0018] Figure 1 It is a front view structural schematic diagram of a novel quantum dot LED light source provided by an embodiment of the utility model;
[0019] Figure 2 It is a schematic diagram of the top view structure of the novel quantum dot LED light source provided by the embodiment of the utility model;
[0020] Figure 3 It is a front view structural diagram of a blue light chip in a novel quantum dot LED light source provided by an embodiment of the utility model;
[0021] Figure 4 The exploded structure of the LED display provided by the embodiment of the utility model is shown in FIG. Figure 1 ;
[0022] Figure 5 The exploded structure of the LED display provided by the embodiment of the utility model is shown in FIG. Figure 2 ;
[0023] Figure 6 It is a flow chart of a method for preparing a novel quantum dot LED light source provided by an embodiment of the utility model;
[0024] Figure 7 It is a flow chart after step s4 in the method for preparing a novel quantum dot LED light source provided in an embodiment of the utility model.
[0025] Description of Reference Numerals
[0026] 1. New quantum dot LED light source; 2. LED display; 11. Bracket; 12. Blue light chip; 13. Casting layer; 14. Substrate; 15. Solder pad; 16. Gold wire; 17. Solid crystal silicone; 21. Backlight panel; 22. LCD panel. DETAILED DESCRIPTION
[0027] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.
[0028] See also Figure 1-Figure 2 , Figure 1 It is a front view structural schematic diagram of a novel quantum dot LED light source provided by an embodiment of the utility model; Figure 21 is a schematic diagram of a top view of a novel quantum dot LED light source provided by an embodiment of the utility model. The novel quantum dot LED light source 1 comprises a bracket 11, a blue light chip 12 and a casting layer 13. The bracket 11 is provided with an installation space for accommodating the blue light chip 12. The casting layer 13 fills the installation space and covers the blue light chip 12. The casting layer 13 comprises red light quantum dots, green light quantum dots and a copolymer, and the copolymer covers the red light quantum dots and the green light quantum dots.
[0029] The blue light chip 12 is installed in the installation space of the bracket 11, and the blue light chip 12 is coated in the installation space under the filling action of the casting layer 13, thereby eliminating the gap in the installation space to reduce the diffusion and loss of the blue light chip 12 when emitting light. The casting layer 13 is formed by uniformly mixing red light quantum dots, green light quantum dots and copolymers, that is, the red light quantum dots and green light quantum dots are coated with copolymers to form the casting layer 13 in parallel. The casting layer 13 can be regarded as a layer of colloid. Compared with the packaging method of the prior art that uses two colloids to be cast successively, the utility model only uses one layer of colloid for packaging, which simplifies the packaging process and reduces the manufacturing cost. In addition, there is no obvious difference in density at each position in the mixed casting layer 13, which can reduce the reflection effect of light and greatly improve the quantum efficiency and light extraction efficiency.
[0030] In the embodiment of the utility model, both the red light quantum dots and the green light quantum dots adopt an alloy core-shell structure, the luminescence peak range of the red light quantum dots is within 620nm-680nm, and the luminescence peak range of the green light quantum dots is within 510nm-550nm.
[0031] Quantum dots with high absorbance alloy core-shell structure are selected because of their high environmental adaptability, narrow luminescence peak width, NTSC color gamut generally reaching more than 110%, high color purity, quantum yield generally reaching more than 90%, and the alloy core-shell of quantum dots mixed with copolymers can improve the structural stability of the quantum dots, that is, improve the structural stability of the casting layer 13, and avoid the generation of void defects inside the casting layer 13 and increase in light energy loss.
[0032] In an embodiment of the present invention, the copolymer includes at least one of poly(methyl methacrylate-co-ethyl acrylate), polystyrene maleic anhydride copolymer, isopropylene maleic anhydride copolymer, poly(methyl methacrylate-co-methacrylic acid), polyisobutyl methacrylate, polybutyl methacrylate, and poly(ethyl methacrylate).
[0033] It should be noted that the above-mentioned materials of the copolymers are direct applications of existing materials. Although the casting layer 13 is formed by mixing the copolymers with red light quantum dots and green light quantum dots, the casting layer 13 still exists in the form of copolymers, red light quantum dots and green light quantum dots. No new substances are produced in the obtained casting layer 13. Therefore, the casting layer 13 of the utility model does not constitute an improvement on the material.
[0034] Please continue reading Figure 1 In the embodiment of the utility model, the novel quantum dot LED light source 1 further includes a substrate 14 and a soldering pad 15 , and the surface of the substrate 14 is attached between the bracket 11 and the soldering pad 15 .
[0035] By bonding the substrate 14 to the outer surface of the bracket 11, when the blue light chip 12 generates heat, the heat can be transferred to the substrate 14 through the bracket 11, thereby achieving the purpose of providing heat dissipation for the blue light chip 12 and preventing the pad 15 from being deformed or short-circuited due to excessive temperature. In the embodiment of the utility model, the substrate 14 can be a metal alloy substrate or a ceramic substrate to provide heat dissipation for the blue light chip 12 and ensure the performance reliability and stability of the new quantum dot LED light source 1.
[0036] In the embodiment of the utility model, the bracket 11 adopts a metal alloy bracket or a ceramic bracket to provide an installation basis for the blue light chip 12. In the embodiment of the utility model, the bracket preferably adopts a ceramic bracket, which can not only play an insulating role between the blue light chip 12 and the ceramic bracket, but also provide heat dissipation for the blue light chip 12. The substrate preferably adopts a metal alloy substrate. Since the thermal conductivity of the metal alloy substrate and the ceramic bracket 11 is different, it can further provide heat dissipation for the blue light chip 12.
[0037] In the embodiment of the utility model, a gold wire 16 is provided on the blue light chip 12, and the blue light chip 12 is connected to the pad 15 through the gold wire 16, so that the external circuit transmits electrical energy to the blue light chip 12 through the gold wire 16 on the pad 15, thereby making the blue light chip 12 electroluminescent.
[0038] See also Figure 3 , Figure 3 1 is a schematic diagram of the front view of the blue light chip in the novel quantum dot LED light source provided by the embodiment of the utility model. In the embodiment of the utility model, the blue light chip 12 is a vertical structure chip, which includes a sapphire substrate, an n-GaN layer, a pn junction and a p-GaN layer from bottom to top, the n-GaN layer is connected to the n-type electrode, and the p-GaN layer is connected to the p-type electrode.
[0039] The blue light chip 12 adopts a vertical structure, with the n-type electrode and the p-type electrode on both sides of the epitaxial layer of the sapphire substrate respectively. The n-electrode allows almost all the current to flow vertically through the n-GaN layer, pn junction and p-GaN layer, and very little current flows laterally, thereby avoiding local high temperature.
[0040] In an embodiment of the utility model, the novel quantum dot LED light source 1 also includes a solid crystal silicone 17 pasted and fixed between the bracket 11 and the blue light chip 12. The blue light chip 12 is pasted to the surface of a designated area in the bracket 11 by the solid crystal silicone 17 to prevent the blue light chip 12 from loosening.
[0041] In an embodiment of the utility model, the height of the casting layer 13 filled in the installation space exceeds the height of the blue light chip 12 and is flush with the upper end surface of the bracket 11, so as to ensure the uniformity of the production process of the new quantum dot LED light source 1. After completing the packaging process, the casting layer 13 is irradiated and cured under the action of a high-pressure mercury lamp to obtain a new quantum dot LED light source 1 with high color gamut and high stability. Compared with the outer resin packaging and thermal curing of conventional LED light sources, the curing time is short. According to production experimental tests, the curing time of the casting layer 13 is only 30s, which is significantly shortened compared to the 2-6h thermal curing form of ordinary LED light sources, thereby improving the production efficiency of LED light sources.
[0042] According to the novel quantum dot LED light source 1, the utility model also provides an LED display screen, see Figure 4-Figure 5 , Figure 4 The exploded structure of the LED display provided by the embodiment of the utility model is shown in FIG. Figure 1 , Figure 5 The exploded structure of the LED display provided by the embodiment of the utility model is shown in FIG. Figure 2 The LED display screen 2 of the utility model comprises a backlight panel 21, a liquid crystal panel and the novel quantum dot LED light source 1 mentioned above. The novel quantum dot LED light source 1 is arranged in an array on the backlight panel 21, and the liquid crystal panel 22 covers the backlight panel.
[0043] Among them, the new quantum dot LED light source 1 includes a bracket 11, a blue light chip 12 and a casting layer 13. The bracket 11 is provided with an installation space for accommodating the blue light chip 12. The casting layer 13 fills the installation space and covers the blue light chip 12. The casting layer 13 includes red light quantum dots, green light quantum dots and copolymers, and the copolymers cover the red light quantum dots and the green light quantum dots.
[0044] The blue light chip 12 is installed in the installation space of the bracket 11, and the blue light chip 12 is covered in the installation space under the filling effect of the casting layer 13, so as to eliminate the gap in the installation space, so as to reduce the diffusion and loss of the blue light chip 12 when emitting light. The casting layer 13 is formed by uniformly mixing red light quantum dots, green light quantum dots and copolymers, that is, the red light quantum dots and green light quantum dots are covered by copolymers and formed into the casting layer 13 in parallel. The casting layer 13 can be regarded as a layer of colloid. Compared with the packaging method of the prior art that uses two colloids to be cast in sequence, In general, the utility model only uses a layer of colloid for packaging, which simplifies the packaging process and reduces the manufacturing cost. In addition, there is no obvious difference in the density of each position in the mixed casting layer 13, which can reduce the reflection effect of light and greatly improve the quantum efficiency and light extraction efficiency. Therefore, in the LED display screen 2 prepared by using the new quantum dot LED light source 1, the light source only needs to pass through a layer of colloid when emitting light, which reduces the number of reflections of light and reduces the loss of light energy, thereby making the picture displayed on the liquid crystal panel 22 closer to the original picture quality and optimizing the user viewing experience.
[0045] Among them, the red light quantum dots and the green light quantum dots both adopt an alloy core-shell structure, the red light quantum dots have a luminescent peak range of 620nm-680nm, the green light quantum dots have a luminescent peak range of 510nm-550nm, and the copolymers include poly(methyl methacrylate-co-ethyl acrylate), polystyrene maleic anhydride copolymer, isopropyl maleic anhydride copolymer, poly(methyl methacrylate-co-methacrylic acid), polyisobutyl methacrylate, polybutyl methacrylate, poly(ethyl methacrylate), and at least one of the following. The quantum dots with an alloy core-shell structure with high absorbance are selected because they have high environmental adaptability, narrow luminescent peak width, NTSC color gamut generally reaching more than 110%, high color purity, and quantum yield generally reaching more than 90%. The alloy core-shell of the quantum dots can improve the structural stability of the quantum dots after being mixed with the copolymer, that is, improve the structural stability of the casting layer 13, and avoid the increase of light energy loss caused by the generation of void defects inside the casting layer 13.
[0046] In the embodiment of the utility model, the novel quantum dot LED light source 1 is arranged in an array on the backlight plate 21, including being arranged in an array on the back panel of the backlight plate 21 and / or being arranged in an array on the side panel of the backlight plate 21, wherein: Figure 4 The new quantum dot LED light source array is laid on the back panel of the backlight plate, so that the liquid crystal panel 22 can achieve a backlight display effect. Figure 5 The new quantum dot LED light source array is laid on the side panel of the backlight plate, so that the liquid crystal panel 22 can achieve a side-lighting display effect.
[0047] According to the above-mentioned novel quantum dot LED light source, the present invention also provides a method for preparing a novel quantum dot LED light source, please refer to Figure 6 , Figure 6 This is a flow chart of a method for preparing a novel quantum dot LED light source provided by an embodiment of the utility model. The preparation method comprises the following steps:
[0048] S1: Selecting red light quantum dots with alloy core-shell structure and green light quantum dots with alloy core-shell structure with high absorbance and placing them in a glass container for mixing to obtain quantum dot dispersion;
[0049] S2: inject the selected copolymer into a glass container and mix it with the quantum dot dispersion, let it stand for 4 hours, and then rotary evaporate for 30 minutes to obtain a casting layer;
[0050] S3: Select the solid crystal silicone to attach the blue light chip to the bottom of the installation space in the bracket, and use the casting layer to fill the installation space;
[0051] S4: Use a high-pressure mercury lamp to irradiate and cure the new quantum dot LED light source that has filled the casting layer.
[0052] The new quantum dot LED light source prepared by the method can reduce the gap in the installation space of the bracket under the filling of the casting layer, thereby reducing the diffusion and loss of the blue light chip when emitting light. Compared with the method of using two layers of colloid to encapsulate the blue light chip in the prior art, the new quantum dot LED light source prepared by the utility model only uses one layer of colloid for encapsulation, which simplifies the encapsulation process and reduces the manufacturing cost. In addition, there is no obvious difference in the density of each position in the mixed casting layer, which can reduce the reflection effect of light and greatly improve the quantum efficiency and light extraction efficiency.
[0053] Among them, when the pouring layer is used to fill the installation space, the height of the pouring layer exceeds the blue light chip and is flush with the upper surface of the bracket to ensure the uniformity of the preparation process of the new quantum dot LED light source. After the pouring layer is filled, the pouring layer is irradiated and cured by a high-pressure mercury lamp for 30 seconds, so that the pouring layer can be cured and the blue light chip can be encapsulated, thereby obtaining a new quantum dot LED light source with high color gamut and high stability. Compared with the outer resin encapsulation and thermal curing of conventional LED light sources, the time required for curing of the utility model is shorter, thereby improving the production efficiency of the LED light source.
[0054] See also Figure 7 , Figure 7 This is a flow chart after step s4 in the method for preparing a novel quantum dot LED light source provided by an embodiment of the utility model, and further includes after step S4:
[0055] S41: attaching and fixing the substrate to the outer surface of the bracket, and installing the pad on the substrate;
[0056] S42: Solder the gold wire on the blue light chip to the pad to form a path.
[0057] After the blue light chip is fixed in the installation space and the casting layer is solidified, the position of the blue light chip can be prevented from changing, which is beneficial to the subsequent welding operation of the gold wire. When welding the gold wire, the substrate is first attached and fixed to the outer surface of the bracket, and then the pad is installed on the substrate. The substrate can absorb the heat generated by the blue light chip and transfer the heat emitted by the blue light chip to the substrate through the bracket, thereby achieving the purpose of providing heat dissipation for the blue light chip, thereby avoiding deformation or short circuit caused by excessive temperature of the pad.
[0058] Among them, the substrate can be a metal alloy substrate or a ceramic substrate, so as to provide heat dissipation for the blue light chip, ensuring the performance reliability and stability of the prepared new quantum dot LED light source. The bracket adopts a metal alloy bracket or a ceramic bracket to provide an installation basis for the blue light chip. In the embodiment of the utility model, the bracket preferably adopts a ceramic bracket, which can not only play an insulating role between the blue light chip and the ceramic bracket, but also provide heat dissipation for the blue light chip. The substrate preferably adopts a metal alloy substrate. Since the thermal conductivity of the metal alloy substrate and the ceramic bracket is different, it can further provide heat dissipation for the blue light chip.
[0059] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0060] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various specific technical features in any appropriate manner. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations. However, these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.
[0061] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present invention.
Claims
1. A new quantum dot LED light source, characterized in that: The novel quantum dot LED light source includes a bracket, a blue light chip and a casting layer. The bracket is provided with an installation space for accommodating the blue light chip. The casting layer fills the installation space and covers the blue light chip. The casting layer includes red light quantum dots, green light quantum dots and a copolymer. The copolymer covers the red light quantum dots and the green light quantum dots.
2. The novel quantum dot LED light source according to claim 1, characterized in that: The red light quantum dots and the green light quantum dots both adopt an alloy core-shell structure. The luminescence peak range of the red light quantum dots is within 620nm-680nm, and the luminescence peak range of the green light quantum dots is within 510nm-550nm.
3. The novel quantum dot LED light source according to claim 1, characterized in that: The novel quantum dot LED light source also includes a substrate and a soldering pad, and the surface of the substrate is attached between the bracket and the soldering pad.
4. The novel quantum dot LED light source according to claim 3, characterized in that: The substrate is a metal alloy substrate or a ceramic substrate, the bracket is a metal alloy bracket or a ceramic bracket, and the substrate and the bracket are made of different materials.
5. The novel quantum dot LED light source according to claim 3, characterized in that: A gold wire is arranged on the blue light chip, and the blue light chip is connected to the pad through the gold wire.
6. The novel quantum dot LED light source according to claim 1, characterized in that: The blue light chip is a vertical structure chip, which includes a sapphire substrate, an n-GaN layer, a pn junction and a p-GaN layer from bottom to top. The n-GaN layer is connected to an n-type electrode, and the p-GaN layer is connected to a p-type electrode.
7. The novel quantum dot LED light source according to claim 1, characterized in that: The novel quantum dot LED light source also includes a solid crystal silicone glue which is pasted and fixed between the bracket and the blue light chip.
8. The novel quantum dot LED light source according to any one of claims 1 to 7, characterized in that: The height of the casting layer filled in the installation space exceeds the height of the blue light chip and is flush with the upper end surface of the bracket.
9. An LED display screen, characterized in that: The LED display screen includes a backlight panel, a liquid crystal panel, and the novel quantum dot LED light source as described in any one of claims 1 to 8, wherein the novel quantum dot LED light source array is arranged on the backlight panel, and the liquid crystal panel covers the backlight panel.
10. The LED display screen according to claim 9, characterized in that: The manner in which the novel quantum dot LED light source array is arranged on the backlight panel includes the array being arranged on the back panel of the backlight panel and / or the array being arranged on the side panel of the backlight panel.