LED light emitting device with inner and outer quantum dot layers

Abstract

The utility model discloses a kind of LED light-emitting devices with inner and outer quantum dot layer, belong to LED technical field.The LED light-emitting device includes the metal substrate, blue light LED array layer, light-transmitting substrate layer and quantum dot layer which are sequentially stacked from bottom to top along vertical direction;The quantum dot layer includes inner quantum dot layer and outer quantum dot layer, the outer quantum dot layer is set to the four around outside of inner quantum dot, and light trap isolation layer is arranged between outer quantum dot layer and inner quantum dot layer.The utility model is set by setting inner quantum dot layer and outer quantum dot layer, and light trap isolation layer is set between the two, to prevent inner quantum dot layer and outer quantum dot layer from mutual influence after emitting light and cause light efficiency difference, so that LED light-emitting device can be realized in the same plane to emit two different colors of light, so that it can utilize quantum dot to overcome the light decay and color accuracy problem of traditional LED light-emitting device, and the light-emitting efficiency of different colors of light can be guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of LED technology, specifically to an LED light-emitting device with inner and outer quantum dot layers. Background Technology

[0002] LEDs are semiconductor light-emitting diodes. Due to their excellent performance such as high brightness, high luminous efficiency, and long lifespan, they are now widely used in the lighting, backlighting, and display industries. However, after prolonged use, the brightness of LED light-emitting devices will gradually decrease. This phenomenon is called light decay, which has a significant impact on the color accuracy (color precision) of light. In addition, the spectra of mixed light sources on the market are relatively mixed, containing other light waves outside the target wavelength, resulting in poor color purity of multi-color LED devices.

[0003] Quantum dots, as an emerging display material and technology, utilize the quantum confinement effect, exhibiting excellent performance with a wide absorption range and narrow emission peak. Furthermore, the emission peak can be continuously adjusted within the visible light range based on the different radii of the quantum dot material, thus achieving ultra-high color gamut display performance. Currently, they are widely used in the backlighting industry for televisions, mobile phones, and computers. Quantum dots of different diameters can produce emitted light of specific wavelengths after absorbing excitation light of a specific wavelength (450nm), and the diameter of the quantum dot is directly proportional to the wavelength of the emitted light. The emitted light exhibits almost no defects in attenuation (color decay) and accuracy (color precision). Therefore, applying quantum dots to LED light-emitting devices can effectively overcome the light attenuation and color precision problems of LED light-emitting devices. However, for multi-color LED light-emitting devices, different colors of light emitted from the same planar quantum dot layer are prone to mutual interference, resulting in poor luminous efficiency and failing to meet the application requirements of applications such as agricultural plant growth lights.

[0004] In view of this, it is essential to develop a multicolor LED light-emitting device that can effectively improve attenuation (color decay) and accuracy (color precision) while ensuring color purity. Utility Model Content

[0005] In order to overcome the shortcomings of the existing technology, the purpose of this utility model is to provide an LED light-emitting device with inner and outer quantum dot layers, which effectively improves the attenuation (color decay) and accuracy (color precision) while avoiding the mutual influence of different colors of light and effectively ensuring color purity, thereby improving the overall stability of the LED light-emitting device.

[0006] To solve the above problems, the technical solution adopted by this utility model is as follows: An LED light-emitting device with inner and outer quantum dot layers includes a metal substrate, a blue LED array layer, a light-transmitting substrate layer and a quantum dot layer stacked vertically from bottom to top; the quantum dot layer includes an inner quantum dot layer and an outer quantum dot layer, the outer quantum dot layer is disposed around the inner quantum dot layer, and a light trap isolation layer is disposed between the outer quantum dot layer and the inner quantum dot layer.

[0007] In a preferred embodiment of this invention, the light trap isolation layer is a carbon nanotube layer.

[0008] In a preferred embodiment of this invention, the surfaces of the quantum dot materials in the inner and outer quantum dot layers are coated with a silicon dioxide layer.

[0009] In a preferred embodiment of this invention, the quantum dot materials in the inner quantum dot layer and the outer quantum dot layer are different.

[0010] More preferably, the quantum dots in the quantum dot material include, but are not limited to, cadmium sulfide, cadmium telluride, zinc selenide, lead sulfide, lead selenide, indium phosphide, and indium arsenide.

[0011] In a preferred embodiment of the present invention, heat dissipation fins are provided on the side of the metal substrate near the blue LED array layer.

[0012] In a preferred embodiment of this utility model, the metal substrate is an aluminum sheet, an aluminum alloy sheet, or a copper sheet.

[0013] In a preferred embodiment of this utility model, a lens is provided between the blue LED array layer and the light-transmitting substrate layer.

[0014] In a preferred embodiment of this utility model, the angle of the lens is 120°±0.5°.

[0015] In a preferred embodiment of this utility model, the lens is a PMMA lens.

[0016] In a preferred embodiment of this utility model, the surface-mount LEDs in the blue LED array layer are at least one of the following: 3014, 1206, 5730, or 2835.

[0017] In a preferred embodiment of this utility model, the light-transmitting substrate layer is one of fluorine-doped tin oxide (FTO), indium tin oxide (ITO), glass, and glass slide.

[0018] Compared with the prior art, the beneficial effects of this utility model are as follows: The LED light-emitting device of this invention sets an inner quantum dot layer and an outer quantum dot layer around the inner quantum dot layer, and sets a light trap isolation layer between the two to prevent the inner and outer quantum dot layers from affecting each other after emitting light, resulting in poor luminous efficiency. This allows the LED light-emitting device to emit two different colors of light on the same plane. In this way, it can not only use quantum dots to overcome the light decay and color accuracy problems of traditional LED light-emitting devices, but also ensure the luminous efficiency of different colors of light. Attached Figure Description

[0019] Figure 1 This is a cross-sectional view of the LED light-emitting device with inner and outer quantum dot layers described in this utility model; Figure 2 This is a top view of the LED light-emitting device with inner and outer quantum dot layers described in this utility model; Explanation of reference numerals in the attached diagram: 1. Metal substrate; 2. Blue LED array layer; 3. Transparent substrate layer; 4. Lens; 5. Quantum dot layer; 6. Inner quantum dot layer; 7. Outer quantum dot layer; 8. Light trap isolation layer. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0021] like Figure 1 As shown, the LED light-emitting device of this invention includes a metal substrate 1, a blue LED array layer 2, a light-transmitting substrate layer 3, and a quantum dot layer 5, which are stacked vertically from bottom to top. The metal substrate 1 is the same size as the light-transmitting substrate layer 3, and heat dissipation fins are provided on the side of the metal substrate 1 closest to the blue LED array layer 2. In some embodiments, the heat dissipation fins are integrally formed on the metal substrate. Preferably, the metal substrate 1 is an aluminum sheet, an aluminum alloy sheet, or a copper sheet. The blue LED array layer 2 includes a plurality of surface-mount LEDs arranged in sequence. The surface-mount LEDs are commercially available surface-mount LEDs, and preferred models include, but are not limited to, 3014, 1206, 5730, or 2835. The light-transmitting substrate layer 3 is various commercially available light-transmitting substrates, including but not limited to fluorine-doped tin oxide (FTO), indium tin oxide (ITO), glass, and glass slides. Figure 2As shown, the quantum dot layer 5 includes an inner quantum dot layer 6 and an outer quantum dot layer 7. The outer quantum dot layer 7 is disposed around the inner quantum dot layer, and a light trap isolation layer 8 is disposed between the outer quantum dot layer 7 and the inner quantum dot layer 6. The quantum dot materials in the inner quantum dot layer 6 and the outer quantum dot layer 7 are different. As can be seen from the above scheme, the blue LED array layer 2 of this invention emits 450nm blue light incident from the transparent substrate layer 3. After conversion processing by the inner quantum dot layer 6 and the outer quantum dot layer 7, different colors of light can be emitted on the same plane, greatly improving the LED light-emitting device's attenuation (color decay) and accuracy (color precision), effectively enhancing the overall stability of the device. Simultaneously, by setting the light trap isolation layer 8 between the inner quantum dot layer 6 and the outer quantum dot layer 7, mutual interference between the inner and outer quantum dot layers after emission is prevented, thus ensuring luminous efficiency.

[0022] In some embodiments, the light trap isolation layer 8 is a carbon nanotube layer to prevent the inner and outer quantum dot layers 7 from interfering with each other after emitting light. Preferably, the surfaces of the quantum dot materials in the inner quantum dot layer 6 and the outer quantum dot layer 7 are coated with a silicon dioxide layer to isolate the quantum dots from water and oxygen corrosion, which is beneficial to improving the stability of the quantum dot layer 5. In this invention, the quantum dots in the quantum dot material include, but are not limited to, cadmium sulfide, cadmium telluride, zinc selenide, lead sulfide, lead selenide, indium phosphide, indium arsenide, etc.; preferably, the diameter of the quantum dots is 2~20nm. In some embodiments, a wide-angle lens 4 is disposed between the blue LED array layer 2 and the light-transmitting substrate layer 3 to excite the inner quantum dot layer 6; preferably, the angle of the lens 4 is 120°±0.5°; the material of the lens 4 is PMMA.

[0023] The following describes in detail the fabrication method of the LED light-emitting device of this invention, using an aluminum sheet as the metal substrate, glass as the light-transmitting substrate, CdSe@ZnS as the quantum dots, and carbon nanotubes as the light-trapping isolation layer: S1. Metal substrate processing: Remove the aluminum sheet and connect the heat dissipation fins to the aluminum substrate via vacuum reflow soldering. The soldering material is indium tin silver alloy (In). 80 Sn 15 Ag5), melting point 120℃; the fin surface has a honeycomb Al2O3 layer generated by micro-arc oxidation, with a pore size of 5-10μm and a layer thickness of 8-12μm.

[0024] S2. Arrange the surface-mount LED devices sequentially on the metal substrate to obtain the LED devices.

[0025] S3. A lens is installed around the internal 4×4 LED device array and PMMA is injected into the lens to obtain a wide-angle lens with a beam angle of 120°±0.5°.

[0026] S4. Use deionized water, acetone, and isopropanol to ultrasonically clean the glass transparent substrate for 15 minutes each, and then perform ultraviolet ozone ion cleaning on the transparent substrate for 30 minutes.

[0027] S5. Preparation of quantum dot materials: Preparation of CdSe quantum dots (S51): Trioctylphosphine selenide (0–0.27 g) was dissolved in trioctylphosphine (4 ml TOP, 97%, Sigma-Aldrich). This solution was then injected into hot oleic acid (2.67 ml, 70%, Aldrich) containing cadmium oxide (0–0.27 g CdO, 99.5%, Aldrich), trioctylphosphine oxide (1.94 g TOPO, 99% Sigma-Aldrich), and hexadecylamine (1.94 g HDA, 98% Aldrich). The reaction mixture was heated under reflux at 220–300 °C for 10 minutes, cooled to room temperature, and then toluene was added. The synthesized quantum dots were centrifuged and washed multiple times at 2000 rpm for 15 minutes, and then redispersed in methanol to remove any unreacted reagents, finally yielding CdSe quantum dots.

[0028] S52. Growth of a zinc sulfide (ZnS) shell on the prepared CdSe quantum dots: A mixture of 0.9 g trioctylphosphine oxide and 0.9 g hexadecylamine was heated to 170 °C in a three-necked flask, and a portion of CdSe solution was added. Subsequently, a premixed solution of 1 ml diethylzinc (Zn(Et)2, Aldrich) with 220 μl hexamethyldithioalkylene ((TMS)2S, Aldrich) and 1 M n-hexane in trioctylphosphine was added dropwise to the reaction vessel. The reaction mixture was stirred at 170 °C for 1 h to obtain CdSe / ZnS core / shell QDs, which were purified and washed. The precipitate was then resuspended in tetrahydrofuran (99.7%, Sigma-Aldrich).

[0029] S53. Coating the CdSe / ZnS quantum dot surface with a silica layer: A CdSe / ZnSQD suspension in tetrahydrofuran was ultrasonically mixed with 150 μl of tetraethyl orthosilicate (TEOS, 98%, Sigma-Aldrich) under a N2 atmosphere. This mixture was then added to 1 ml of Igepal CO-520 (Sigma-Aldrich) and 10 ml of cyclohexane (99%, Fisher) and stirred for 30 min. 150 μl of ammonia solution (33%) was added dropwise and stirred thoroughly.

[0030] S54. Purify the silica-coated CdSe / ZnS quantum dots by continuously washing with dry 2-propanol, ethanol, and water. Repeat the above steps 2-3 times to further remove impurities and excess ligands from the reaction system, obtaining a pure quantum dot solution. Transfer the quantum dot solution to a suitable container and seal it for storage. If drying the quantum dots is required, place the solution in a vacuum drying oven and dry at 40-60°C for several hours until the solvent completely evaporates. Place the dried quantum dot particles in a grinding mortar and grind them in the same direction for 10-15 minutes using a grinding rod to obtain quantum dot powder.

[0031] S6. Preparation of quantum dot layers: The target color quantum dot powder and UV curing agent are mixed at a ratio of 1:5 using a dot coating method, and then evenly coated on a clean, translucent substrate within a predetermined range on both the inner and outer sides. After the inner quantum dot layer is coated, carbon nanotube material is evenly dotted around the inner quantum dot layer. After the carbon nanotube coating is completed, the outer quantum dot layer is dotted to separate the inner and outer quantum layers. After dot coating, the material is placed under a UV curing lamp for 30 minutes for UV curing. After curing, a quantum dot material layer is obtained.

[0032] S7. The LED device with the lens is bonded to the back of the transparent substrate using transparent adhesives such as glass glue or UV-curing adhesive to obtain an LED light-emitting device with inner and outer quantum dot layers.

[0033] In summary, this invention sets an inner quantum dot layer and an outer quantum dot layer around the inner quantum dot layer, and sets a light trap isolation layer between the two to prevent the inner and outer quantum dot layers from affecting each other after emitting light, thus preventing poor luminous efficiency. This allows the LED light-emitting device to emit two different colors of light on the same plane. In this way, quantum dots can be used to overcome the light decay and color accuracy problems of traditional LED light-emitting devices, while ensuring the luminous efficiency of different colors of light.

[0034] The above embodiments are merely preferred embodiments of this utility model and should not be construed as limiting the scope of protection of this utility model. Any non-substantial changes and substitutions made by those skilled in the art based on this utility model shall fall within the scope of protection claimed by this utility model.

Claims

1. An LED light emitting device having inner and outer quantum dot layers, characterized by: The metal substrate, the blue light LED array layer, the light-transmitting substrate layer and the quantum dot layer are sequentially stacked in the vertical direction from bottom to top.

2. The LED light emitting device with inner and outer quantum dot layers of claim 1, wherein: The light-trap isolation layer is a carbon nanotube layer.

3. The LED light emitting device with inner and outer quantum dot layers of claim 1 or 2, wherein: The quantum dot materials in the inner quantum dot layer and the outer quantum dot layer are different.

4. The LED light emitting device with inner and outer quantum dot layers of claim 1 or 2, wherein: The metal substrate is provided with a heat dissipation fin on the side close to the blue light LED array layer.

5. The LED light emitting device with inner and outer quantum dot layers of claim 1 or 2, wherein: The metal substrate is an aluminum sheet, an aluminum alloy sheet or a copper sheet.

6. The LED light emitting device with inner and outer quantum dot layers of claim 1 or 2, wherein: The blue light LED array layer is provided with a lens between the blue light LED array layer and the light-transmitting substrate layer.

7. The LED light emitting device with inner and outer quantum dot layers of claim 6, wherein: The angle of the lens is 120°±0.5°.

8. The LED light emitting device with inner and outer quantum dot layers of claim 1 or 2, wherein: The patch LED type in the blue light LED array layer is at least one of 3014, 1206, 5730 or 2835.

9. The LED light emitting device with inner and outer quantum dot layers of claim 1 or 2, wherein: The light-transmitting substrate layer is one of fluorine-doped tin oxide (FTO), indium tin oxide (ITO), glass and a glass slide.

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