A three-blue full-spectrum LED lamp bead

Abstract

The present invention provides a three-blue full-spectrum LED lamp bead, which relates to the field of LED technology. The three-blue full-spectrum LED lamp bead provided by the present invention includes a first blue light chip with a peak wavelength of 460-465nm, a second blue light chip with a peak wavelength of 430-435nm, and a third blue light chip with a peak wavelength of 449-454nm; the first blue light chip, the second blue light chip, and the third blue light chip are excited and coupled to full-spectrum white light after irradiating a fluorescent encapsulation layer; the fluorescent encapsulation layer is a cured modified phosphor, and the modified phosphor is a mixed and modified fluorescent blue powder, fluorescent red powder, fluorescent cyan powder, and fluorescent yellow-green powder. The present invention utilizes three blue light chips with different wavelengths to combine to supplement the spectrum of blue light loss, and after combining with the fluorescent encapsulation layer, it can improve the lighting quality of white light emitted by the full-spectrum LED, so that the spectrum continuity is better, and the color rendering ability and color reproduction ability of the lamp bead are improved.

Description

Technical Field

[0001] The present invention relates to the field of LED technology, and in particular to a three-blue light full-spectrum LED lamp bead. Background Art

[0002] With the continuous improvement of living standards, people's demands for lighting quality are becoming increasingly higher. High-quality, full-spectrum lighting has become a new trend in "healthy and green lighting" worldwide. White light-emitting diodes (LEDs) have become the mainstream lighting method due to their advantages such as low energy consumption, long life, compact size, fast response, high light efficiency, and pollution-free. However, existing white LEDs have problems such as low color rendering index, high color temperature, and blue light hazards. Compared with conventional white light LEDs, full-spectrum white light LEDs have a wide spectral coverage, close to the visible light spectrum of sunlight, good spectral continuity, and a spectral distribution without obvious peaks and valleys. They have an excellent color rendering index and a strong ability to reproduce the color of objects.

[0003] Currently, the commonly used full-spectrum white light LEDs mainly use a combination of red, green and blue light-emitting chips, and blue light chips to excite the full spectrum. The red, green and blue light-emitting chip combination is achieved by combining a red light chip + a green light chip + a blue light chip to obtain full-spectrum white light, while the blue light chip excites the full spectrum by combining an LED blue light chip with fluorescent yellow-green powder, fluorescent red powder, and fluorescent blue-green powder. The blue light is used to excite the outer fluorescent layer and couple out full-spectrum white light.

[0004] However, since the red, green and blue light-emitting chip combination requires the use of three chips of different colors, the number of chips used is too large and the cost is high. In addition, it takes too much time to debug the light emission after the combination, and the overall application is relatively slow. In the blue light chip excitation full spectrum solution, since the blue light is entirely provided by the blue light chip, the color rendering ability and color reproduction of the full-spectrum LED white light are not high, and the full-spectrum white light it emits has a spectrum deficiency. Therefore, there is an urgent need to provide a solution to improve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a three-blue light full-spectrum LED lamp bead, which uses a combination of three blue light chips with different wavelengths to supplement the spectrum missing from blue light, and when combined with a fluorescent packaging layer, it can improve the lighting quality of white light emitted by the full-spectrum LED, making the spectrum continuity better, and improving the color rendering ability and color reproduction ability of the lamp bead.

[0006] The present invention provides a three-blue light full-spectrum LED lamp bead, including a first blue light chip with a peak wavelength of 460-465nm, a second blue light chip with a peak wavelength of 430-435nm, and a third blue light chip with a peak wavelength of 449-454nm; the first blue light chip, the second blue light chip, and the third blue light chip are excited and coupled to form full-spectrum white light after irradiating a fluorescent encapsulation layer; the fluorescent encapsulation layer is a cured modified phosphor, and the modified phosphor is a mixed and modified fluorescent blue powder, fluorescent red powder, fluorescent cyan powder, and fluorescent yellow-green powder.

[0007] The LED lamp beads provided by the present invention combine a first blue light chip, a second blue light chip, and a third blue light chip with different peak wavelengths, and utilize the wavelength range to combine the spectrum missing blue light. After modifying the fluorescent blue powder, fluorescent red powder, fluorescent cyan powder, and fluorescent yellow-green powder, they can be better combined with the three blue light chips, thereby greatly improving the spectral continuity and improving the color rendering ability and color reproduction.

[0008] Optionally, the fluorescent encapsulation layer includes modified fluorescent powder, resin and functional additives.

[0009] Optionally, the preparation method of the modified phosphor includes: stirring and mixing the surface-activated mixed phosphor in ethyl orthosilicate, and then separating and drying to obtain a modified mixed powder; keeping the modified mixed powder at 60-80°C, mixing it with a silane modifier, and ultrasonically reacting it, separating and drying it to obtain a modified phosphor; the mixed phosphor includes fluorescent blue powder, fluorescent red powder, fluorescent cyan powder and fluorescent yellow-green powder.

[0010] Optionally, when the surface-activated mixed phosphor is stirred and mixed in tetraethyl orthosilicate, the mass ratio of the mixed phosphor to the tetraethyl orthosilicate is 1:(2-3).

[0011] Optionally, when the surface-activated mixed phosphor powder is stirred and mixed in tetraethyl orthosilicate, the mixed phosphor powder includes fluorescent blue powder, fluorescent red powder, fluorescent cyan powder and fluorescent yellow-green powder in a mass mixing ratio of 1: (0.2-0.3): (0.15-0.2): (0.05-0.1).

[0012] Optionally, when the surface-activated mixed phosphor powder is stirred and mixed in ethyl orthosilicate, the average particle size of the mixed phosphor powder is 5-10 μm.

[0013] Optionally, when the surface-activated mixed phosphor is stirred and mixed in ethyl orthosilicate: the mixed phosphor is surface-activated in a silicon-containing active agent in advance, and the silicon-containing active agent includes one of diethylaminomethyltriethoxysilane, anilinemethyltriethoxysilane, dichlorodimethylsilane, γ-aminopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane.

[0014] Optionally, when the surface-activated mixed phosphor powder is stirred and mixed in tetraethyl orthosilicate: the surface-activated mixed phosphor powder is stirred and mixed in tetraethyl orthosilicate at 35-45°C.

[0015] Optionally, when the surface-activated mixed phosphor powder is stirred and mixed in ethyl orthosilicate: the surface-activated mixed phosphor powder is ultrasonically mixed in ethyl orthosilicate.

[0016] Optionally, when the modified mixed powder is obtained by separation and drying: the surface-activated mixed phosphor is stirred and mixed in ethyl orthosilicate, and then filtered and separated under reduced pressure and dried to obtain the modified mixed powder.

[0017] Optionally, when the modified mixed powder is obtained by separation and drying: after separation, the modified mixed powder is dried at 70-80°C to obtain the modified mixed powder.

[0018] Optionally, when the modified mixed powder is obtained by separation and drying: the modified mixed powder is obtained by drying in a vacuum environment after separation.

[0019] Optionally, when the modified mixed powder is obtained by separation and drying: after separation, the modified mixed powder is washed in a cycle with deionized water and anhydrous ethanol, and then dried to obtain the modified mixed powder.

[0020] Optionally, when the modified mixed powder is kept at 60-80° C. and then mixed with a silane modifier for ultrasonic reaction: the silane coupling agent includes one of diethylaminomethyltriethoxysilane, anilinemethyltriethoxysilane, dichlorodimethylsilane, γ-aminopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane.

[0021] Optionally, when the modified mixed powder is kept at 60-80° C. and then mixed with the silane modifier for ultrasonic reaction, the mass ratio of the modified mixed powder to the silane coupling agent is 1:(0.2-0.3).

[0022] Optionally, when the modified mixed powder is kept at 60-80°C and then mixed with the silane modifier for ultrasonic reaction: the silane coupling agent is dissolved in an organic solvent to prepare a silane solution, and then the modified mixed powder is kept at 60-80°C and added to the silane solution for mixing and ultrasonic reaction.

[0023] Optionally, when the modified mixed powder is kept at 60-80° C. and then mixed with the silane modifier for ultrasonic reaction: the modified mixed powder is kept at 60-80° C. in a vacuum environment.

[0024] Optionally, when the modified mixed powder is kept at 60-80° C. and then mixed with the silane modifier for ultrasonic reaction: the modified mixed powder is kept at 60-80° C. and then mixed with the silane coupling agent, and then ultrasonically mixed and reacted at a frequency of 20-30 kHz.

[0025] Optionally, when the modified phosphor is prepared by separation and drying: after mixing and ultrasonic reaction, the modified phosphor is prepared by vacuum filtration and drying.

[0026] Optionally, when the modified phosphor is obtained by separation and drying: after separation, the modified phosphor is dried at 40-60° C. to obtain the modified phosphor.

[0027] Optionally, when the modified phosphor is obtained by separation and drying: the modified phosphor is obtained by drying in a vacuum environment after separation.

[0028] Optionally, when the modified phosphor is obtained by separation and drying: after separation, the modified phosphor is rinsed in a cycle with deionized water and anhydrous ethanol, and then dried to obtain the modified phosphor.

[0029] Optionally, before stirring and mixing the surface-activated mixed phosphor in tetraethyl orthosilicate, the fluorescent blue powder, fluorescent red powder, fluorescent cyan powder and fluorescent yellow-green powder are ball-milled and blended to prepare a primary mixture, and then the primary mixture is ultrasonically mixed with deionized water to form a suspension, and the suspension is spray-dried at 150-180°C to obtain the mixed phosphor.

[0030] Optionally, the fluorescent encapsulation layer comprises, by mass, 2-3 parts of modified fluorescent powder, 6-8 parts of resin and 1-2 parts of functional additives.

[0031] Optionally, the resin includes one of phenyl vinyl silicone resin, acrylic resin, and alicyclic epoxy resin.

[0032] Optionally, the functional additives include a defoaming agent, an antioxidant, and a lubricant, and the defoaming agent includes one of a silicone defoaming agent and an acrylate defoaming agent, the antioxidant includes one of antioxidant 1010 and a phosphite, and the lubricant includes one of stearic acid, calcium stearate, and zinc stearate.

[0033] Optionally, after the first blue light chip, the second blue light chip and the third blue light chip irradiate the fluorescent packaging layer and are excited and coupled into full-spectrum white light, the wavelength difference between the three blue lights in the full-spectrum white light is 3-4%.

[0034] Optionally, the relative spectral intensity of blue light of the first blue light chip, the second blue light chip and the third blue light chip is 0.6-1.2.

[0035] Optionally, the peak wavelength of the fluorescent red powder is 645-655 nm.

[0036] Optionally, the peak wavelength of the fluorescent cyan powder is 490-495 nm.

[0037] Optionally, the peak wavelength of the fluorescent blue powder is 495-500 nm.

[0038] Optionally, the peak wavelength of the fluorescent yellow-green powder is 520-540 nm.

[0039] Optionally, the red fluorescent powder includes europium-doped nitride fluorescent powder.

[0040] Optionally, the fluorescent cyan powder includes chlorophosphate fluorescent powder.

[0041] Optionally, the fluorescent blue powder includes chlorophosphate fluorescent powder.

[0042] Optionally, the fluorescent yellow-green powder includes aluminate yellow-green powder. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the common meanings understood by people with ordinary skills in the field to which the present invention belongs.

[0044] This invention provides a triple-blue full-spectrum LED lamp bead, comprising a first blue chip with a peak wavelength of 460-465nm, a second blue chip with a peak wavelength of 430-435nm, and a third blue chip with a peak wavelength of 449-454nm. By combining three blue chips with different wavelength ranges, the missing blue light spectrum can be supplemented, thereby improving lighting quality and spectral continuity.

[0045] Specifically, the dominant wavelength of the first blue light chip is 465-470nm, the dominant wavelength of the second blue light chip is 435-440nm, and the dominant wavelength of the third blue light chip is 452.5-457.5nm. In practice, the first, second, and third blue light chips are connected in series and have the same size, thereby maintaining a consistent blue light energy distribution across the spectrum. Specifically, the wavelength and size of the blue light chips in the LED lamp beads can be configured according to actual needs.

[0046] Specifically, after the first blue light chip, the second blue light chip and the third blue light chip are combined, the peak wavelength of the mixed blue light is 450-455nm, the main wavelength is 450-460nm, and the wavelength difference between the first blue light chip, the second blue light chip and the third blue light chip in the spectrum is 10-20nm. The trough between the blue light peaks of the first blue light chip, the second blue light chip and the third blue light chip is 50-90% of the high-band blue light energy, and the blue light relative spectral intensity is 0.6-1.2.

[0047] In practice, a full-spectrum LED lamp bead also includes a fluorescent encapsulation layer encapsulated around the first, second, and third blue light chips. The blue light emitted by the first, second, and third blue light chips is coupled through the fluorescent encapsulation layer to produce full-spectrum white light. Specifically, after the first, second, and third blue light chips are installed in series, an uncured fluorescent encapsulation layer is applied to their surfaces. Once cured, the full-spectrum LED lamp bead is produced.

[0048] Specifically, the fluorescent encapsulation layer comprises a cured modified phosphor, and the modified phosphor comprises a mixture of modified blue, red, cyan, and yellow-green fluorescent powders. By mixing and modifying the different phosphors, the dispersion of the different phosphors within the fluorescent encapsulation layer can be effectively improved, while also helping to improve the fluorescent encapsulation layer's resistance to light aging, thereby facilitating improved lighting quality stability during long-term use. Specifically, after coupling the fluorescent encapsulation layer, the wavelength difference between the three blue lights in the full-spectrum white light generated by the first, second, and third blue light chips is 3-4%.

[0049] In some embodiments, the preparation method of the modified phosphor comprises: S1, stirring and mixing the surface-activated mixed phosphor in ethyl orthosilicate, and then separating and drying to obtain a modified mixed powder; S2, heating the modified mixed powder at 60-80° C., mixing the modified mixed powder with a silane modifier, and ultrasonically reacting the mixture, separating and drying to obtain a modified phosphor;

[0050] In practice, the mixed phosphor powder used in step S1 includes fluorescent blue powder, fluorescent red powder, fluorescent cyan powder, and fluorescent yellow-green powder. Specifically, the peak wavelength of the fluorescent blue powder is 495-500nm, the peak wavelength of the fluorescent red powder is 645-655nm, the peak wavelength of the fluorescent cyan powder is 490-495nm, and the peak wavelength of the fluorescent yellow-green powder is 520-540nm.

[0051] In some embodiments, the mixed phosphor powder used in step S1 includes blue fluorescent powder, red fluorescent powder, cyan fluorescent powder, and yellow-green fluorescent powder in a mass ratio of 1: (0.2-0.3): (0.15-0.2): (0.05-0.1). In practice, mixing the blue fluorescent powder, red fluorescent powder, cyan fluorescent powder, and yellow-green fluorescent powder in this mass ratio facilitates coupling of the blue light emitted by the first blue light chip, the second blue light chip, and the third blue light chip into the phosphor encapsulation layer, thereby emitting full-spectrum white light.

[0052] In some embodiments, the fluorescent blue powder in the mixed phosphor powder in step S1 includes chlorophosphate blue phosphor powder, and specifically the chlorophosphate blue phosphor powder can be Sr5(PO4)3Cl:Eu 2+ ; The fluorescent red powder includes europium-doped nitride phosphor, specifically the fluorescent red powder can be (Ca, Sr)AlSiN3:Eu 2+ 、(Ca,Sr)2Si5N8:Eu 2+ One of the fluorescent blue powder includes a chlorophosphate cyan fluorescent powder, specifically the fluorescent blue powder can be (Ba, Sr) 5 (PO4) 3Cl: Eu 2+ ; Fluorescent yellow-green powder includes aluminate yellow-green powder, specifically Y3Ga 2.5 Al 2.5 O 12 :Ce 3+ 、Lu3Al5O 12 :Ce 3+ One of them.

[0053] In some embodiments, when executing step S1, the fluorescent blue powder, fluorescent red powder, fluorescent cyan powder and fluorescent yellow-green powder are ball-milled and blended in advance to prepare a primary mixture, and then the primary mixture is ultrasonically mixed with deionized water to form a suspension, and the suspension is spray-dried at 150-180°C to obtain a mixed fluorescent powder.

[0054] In practice, pre-ball milling the fluorescent blue, red, cyan, and yellow-green powders helps improve the uniformity of the mixture and particle size. Specifically, the four phosphors can be ball-milled for 30 minutes using zirconium oxide balls at a 20:1 ball-to-material ratio to produce a preliminary mix. The average particle size of the preliminary mix is ​​5-10 μm.

[0055] Furthermore, by preparing the initial mixture into a suspension and spray drying it, the four phosphors can be further mixed through spray drying. Furthermore, during the spray drying process, the suspension is poured into the spray drying equipment and spray-dried at an inlet air temperature of 150-180°C, which helps improve drying efficiency and effectiveness. Furthermore, the rapid friction caused by air during the spray drying process helps to reduce surface defects in the mixed phosphors, thereby increasing the surface active sites of the mixed phosphors and pre-activating the surface of the mixed phosphors.

[0056] In some embodiments, during step S1, the mixed phosphor powder is pre-activated in a silicon-containing active agent to introduce silicon-containing active groups onto the surface of the mixed phosphor powder. This improves the surface activity of the mixed phosphor powder and enables subsequent surface modification of the mixed phosphor powder. Furthermore, treating the mixed phosphor powder in a silicon-containing active agent promotes repulsion between the mixed phosphor powders, thereby preventing agglomeration of the mixed phosphor powder.

[0057] Specifically, when the mixed phosphor is subjected to surface activation treatment in a silicon-containing active agent, the silicon-containing active agent used includes one of diethylaminomethyltriethoxysilane, anilinomethyltriethoxysilane, dichlorodimethylsilane, γ-aminopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane. In practice, the silicon-containing active agent can be pre-dissolved in an organic solvent to form a silicon-containing active solution. The mixed phosphor is then added to the active solution and ultrasonically dispersed for surface activation.

[0058] In practice, when the mixed phosphor is surface-activated in a silicon-containing active agent, the mass ratio of the mixed phosphor to the silicon-containing active agent is 1:(0.2-0.25). This specific mass ratio allows the silicon-containing active agent to uniformly contact the surface of the mixed phosphor, thereby enhancing the surface activation effect of the silicon-containing active agent on the mixed phosphor.

[0059] In some embodiments, when the surface-activated mixed phosphor is stirred and mixed in ethyl orthosilicate during step S1, the mass ratio of the mixed phosphor to ethyl orthosilicate is 1:(2-3). In fact, since the surface activation treatment of the mixed phosphor with the silicon-containing active agent is performed on the mixed phosphor, the surface weight gain of the mixed phosphor is not significant macroscopically. In addition, after the mixed phosphor and ethyl orthosilicate are mixed in a specific mass ratio, it is beneficial for the ethyl orthosilicate to fully contact with the mixed phosphor and hydrolyze on the surface of the mixed phosphor. In addition, the silicon-containing groups on the surface of the mixed phosphor can improve the uniformity of the nano-silicon dioxide formed by ethyl orthosilicate on the surface of the mixed phosphor.

[0060] In some embodiments, during step S1, the surface-activated mixed phosphor powder is stirred in ethyl orthosilicate at 35-45°C. This temperature environment facilitates improving the surface modification effect and modification uniformity of the mixed phosphor powder by ethyl orthosilicate. In practice, the ethyl orthosilicate can be kept warm in a water bath or oil bath at 35-45°C, and the surface-activated mixed phosphor powder can be pre-heated at 35-45°C.

[0061] In some embodiments, when executing step S1, the surface-activated mixed phosphor is ultrasonically mixed in ethyl orthosilicate. By utilizing the cavitation effect brought about by ultrasound, the dispersion uniformity of the mixed phosphor in ethyl orthosilicate can be effectively improved and the agglomeration of the mixed phosphor in ethyl orthosilicate can be further avoided. In addition, the ultrasonic cavitation effect can also be used to remove tiny bubbles attached to the surface of the mixed phosphor, thereby facilitating surface contact between ethyl orthosilicate and the mixed phosphor.

[0062] In some embodiments, during the separation and drying step S1 to obtain the modified mixed powder, the mixed phosphor powder and ethyl orthosilicate are subjected to vacuum filtration to separate the surface-modified mixed phosphor powder, which is then dried to obtain the modified mixed powder. In practice, the surface of the modified mixed powder comprises a nano-silicon dioxide layer formed by the hydrolysis of ethyl orthosilicate and silicon-containing groups.

[0063] In some embodiments, after the surface-modified mixed phosphor powder is separated in step S1, it is dried in a vacuum environment at 70-80°C to produce a modified mixed powder. In practice, the surface-modified mixed phosphor powder can be dried in a vacuum drying oven to a constant weight, which facilitates the full hydrolysis of the ethyl orthosilicate attached to the surface and improves the dryness of the modified mixed powder.

[0064] In some embodiments, after the surface-modified mixed phosphor powder is separated during step S1, it is rinsed with deionized water and anhydrous ethanol in a cycle, and then dried to produce a modified mixed powder. Specifically, the mixed phosphor powder can be rinsed with deionized water and anhydrous ethanol in a cycle three times. Alternatively, the mixed phosphor powder can be centrifuged at 200-300 rpm using alternating deionized water and anhydrous ethanol.

[0065] In some embodiments, in step S2, when the modified mixed powder is kept at 60-80° C. and then mixed with a silane modifier for ultrasonic reaction, the silane modifier used includes one of diethylaminomethyltriethoxysilane, anilinemethyltriethoxysilane, dichlorodimethylsilane, γ-aminopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane. In practice, the silane modifier and the silicon-containing active agent are independent of each other.

[0066] Specifically, the use of a silane coupling agent in step S2 can surface-treat the modified mixed powder and lubricate the silicon dioxide layer formed on the surface of the modified mixed powder, thereby facilitating uniform dispersion of the modified mixed powder within the phosphor encapsulation layer. Furthermore, the surface treatment of the modified mixed powder with a silane coupling agent can form a silicon-containing active layer on the surface of the modified mixed powder, thereby forming a multi-layer structure on the phosphor surface, which can improve the light aging resistance and service life of the phosphor.

[0067] In some embodiments, when executing step S2, the mass ratio of the modified mixed powder to the silane coupling agent used is 1:(0.2-0.3). In fact, by mixing the modified mixed powder and the silane coupling agent in a specific ratio, it is beneficial to adjust the degree of surface modification of the modified mixed powder by the silane coupling agent, and then adjust the thickness of the silicon-containing active layer added to the surface of the modified mixed powder, which is beneficial to ensure the surface lubricity and dispersibility of the modified mixed powder.

[0068] In some embodiments, during step S2, a silane coupling agent may be pre-dissolved in an organic solvent to prepare a silane solution. The modified mixed powder is then insulated at 60-80°C and then placed into the silane solution for mixing and ultrasonic reaction. Dissolving the silane coupling agent prior to use can facilitate surface contact between the silane coupling agent and the modified mixed powder. Specifically, the organic solvent can be selected from commonly used organic solvents in the art, and must be capable of dissolving the silane coupling agent and non-reactive with the silane coupling agent and the modified mixed powder.

[0069] In some embodiments, during step S2, the modified mixed powder can be kept at 60-80°C in a vacuum environment to prevent oxidation of the silicon-containing active layer on the surface of the modified mixed powder by the oxidizing gas during the drying process. Specifically, the modified mixed powder can be kept at 60-80°C and then mixed with a silane coupling agent, and ultrasonically mixed at a frequency of 20-30 kHz.

[0070] In some embodiments, when performing separation and drying in step S2 to obtain the modified phosphor, after the mixed ultrasonic reaction, solid-liquid separation is performed using a separation method commonly used in the art, such as vacuum filtration, and the resulting solid is dried to obtain the modified phosphor. In practice, after the solid-liquid separation, the modified phosphor is obtained by drying in a vacuum environment at 40-60°C. Furthermore, the modified phosphor can be rinsed with deionized water and anhydrous ethanol before drying.

[0071] In fact, in addition to the modified phosphor, the fluorescent encapsulation layer also includes resin and functional additives. In the fluorescent encapsulation layer, the resin mainly plays the role of a matrix, which can accommodate the modified phosphor and functional additives, and use the solid structure formed after the resin itself is cured to protect the first blue light chip, the second blue light chip and the second blue light chip. The functional additives can give the fluorescent encapsulation layer different properties, such as improving structural strength.

[0072] In some embodiments, the phosphor encapsulation layer comprises, by weight, 2-3 parts of modified phosphor, 6-8 parts of resin, and 1-2 parts of a functional additive. In practice, the resin used in the phosphor encapsulation layer is one of phenyl vinyl siloxane resin, acrylic resin, and alicyclic epoxy resin. The functional additive includes a defoamer, an antioxidant, and a lubricant. The defoamer includes one of an organosilicon defoamer and an acrylate defoamer. The antioxidant includes one of antioxidant 1010 and a phosphite. The lubricant includes one of stearic acid, calcium stearate, and zinc stearate.

[0073] Example 1

[0074] This embodiment 1 provides a method for preparing a modified phosphor, comprising the following steps:

[0075] S0, fluorescent blue powder (Sr5(PO4)3Cl:Eu 2+ )、Fluorescent red powder((Ca,Sr)AlSiN3:Eu 2+ )、Phosphor Blue Powder((Ba,Sr)5(PO4)3Cl:Eu 2+ ) and fluorescent yellow-green powder (Y3Ga 2.5 Al 2.5 O 12 :Ce 3+ ) were mixed in a mass ratio of 1:0.25:0.17:0.08 and placed in a ball mill, using zirconium oxide as ball milling balls and a ball-to-material ratio of 20:1, and ball milling was carried out at a speed of 200 rpm for 30 minutes to prepare a primary mixture, and the primary mixture was mixed with deionized water to prepare a suspension with a solid-liquid ratio of 0.1 g / mL, and the suspension was spray-dried in a spray drying equipment at an inlet air temperature of 160° C. to obtain a mixed phosphor;

[0076] S1. After diluting γ-aminopropyltrimethoxysilane with anhydrous ethanol to prepare a 20% γ-aminopropyltrimethoxysilane solution, the mixed phosphor is added to the γ-aminopropyltrimethoxysilane solution (the mass ratio of the mixed phosphor to γ-aminopropyltrimethoxysilane is 1:0.23), ultrasonically mixed for 15 minutes in a 35°C water bath environment and an ultrasonic frequency of 25kHz, filtered under reduced pressure and dried in a 55°C vacuum drying oven to constant weight to obtain a surface-activated mixed phosphor; the surface-activated mixed phosphor is mixed with ethyl orthosilicate in a mass ratio of 1:2.5, kept warm in a 40°C water bath environment and ultrasonically mixed at 20kHz for 5 minutes, kept warm for 30 minutes and filtered under reduced pressure, rinsed three times with deionized water and anhydrous ethanol, and dried in a 75°C vacuum drying oven to constant weight to obtain a modified mixed powder;

[0077] S2. γ-aminopropyltrimethoxysilane was diluted with anhydrous ethanol to prepare a 20% γ-aminopropyltrimethoxysilane solution, which was then treated at a constant temperature in a 70°C water bath. The modified mixed powder was preheated in a 70°C vacuum environment for 1 hour, and the preheated modified mixed powder was mixed with the γ-aminopropyltrimethoxysilane solution (the mass ratio of the modified mixed powder to γ-aminopropyltrimethoxysilane was 1:0.25). The mixture was ultrasonically mixed at 25 kHz in a 70°C water bath for 5 minutes, kept warm for 1 hour, and filtered under reduced pressure. The mixture was then rinsed three times with deionized water and anhydrous ethanol, and dried in a 55°C vacuum drying oven to constant weight to obtain the modified phosphor.

[0078] Example 2

[0079] This embodiment 2 provides a method for preparing a modified phosphor, comprising the following steps:

[0080] S0, fluorescent blue powder (Sr5(PO4)3Cl:Eu 2+ )、Fluorescent red powder((Ca,Sr)AlSiN3:Eu 2+ )、Phosphor Blue Powder((Ba,Sr)5(PO4)3Cl:Eu 2+ ) and fluorescent yellow-green powder (Y3Ga 2.5 Al 2.5 O 12 :Ce 3+ ) were mixed in a mass ratio of 1:0.25:0.17:0.08 and placed in a ball mill, using zirconium oxide as ball milling balls and a ball-to-material ratio of 20:1, and ball milling was carried out at a speed of 200 rpm for 30 minutes to prepare a primary mixture, and the primary mixture was mixed with deionized water to prepare a suspension with a solid-liquid ratio of 0.1 g / mL, and the suspension was spray-dried in a spray drying equipment at an inlet air temperature of 165° C. to obtain a mixed phosphor;

[0081] S1. After γ-aminopropyltriethoxysilane (KH-550) was diluted with anhydrous ethanol to prepare a γ-aminopropyltriethoxysilane solution with a concentration of 23%, the mixed phosphor was added to the γ-aminopropyltriethoxysilane solution (the mass ratio of the mixed phosphor to γ-aminopropyltriethoxysilane was 1:0.24), and ultrasonically mixed for 15 minutes in a 35°C water bath environment and an ultrasonic frequency of 25 kHz. The mixture was then filtered under reduced pressure and dried in a vacuum drying oven at 60°C to constant weight to obtain a surface-activated mixed phosphor. The surface-activated mixed phosphor was mixed with ethyl orthosilicate in a mass ratio of 1:2.5, kept warm in a 40°C water bath environment and ultrasonically mixed at 20 kHz for 5 minutes, kept warm for 30 minutes, filtered under reduced pressure, and rinsed three times with deionized water and anhydrous ethanol. The mixture was then dried in a vacuum drying oven at 75°C to constant weight to obtain a modified mixed powder.

[0082] S2. γ-aminopropyltriethoxysilane (KH-550) was diluted with anhydrous ethanol to prepare a 20% γ-aminopropyltriethoxysilane solution, which was then treated at a constant temperature in a 70°C water bath. The modified mixed powder was preheated in a 70°C vacuum environment for 1 hour, and the preheated modified mixed powder was mixed with the γ-aminopropyltriethoxysilane solution (the mass ratio of the modified mixed powder to γ-aminopropyltriethoxysilane was 1:0.25). The mixture was ultrasonically mixed at 25 kHz in a 70°C water bath for 5 minutes, kept warm for 1 hour, and filtered under reduced pressure. The mixture was then rinsed three times with deionized water and anhydrous ethanol, and dried in a 55°C vacuum drying oven to constant weight to obtain the modified phosphor.

[0083] Example 3

[0084] This embodiment 3 provides a method for preparing a modified phosphor, comprising the following steps:

[0085] S0, fluorescent blue powder (Sr5(PO4)3Cl:Eu 2+ )、Fluorescent red powder((Ca,Sr)AlSiN3:Eu 2+ )、Phosphor Blue Powder((Ba,Sr)5(PO4)3Cl:Eu 2+ ) and fluorescent yellow-green powder (Y3Ga 2.5 Al 2.5 O 12 :Ce 3+ ) were mixed in a mass ratio of 1:0.25:0.17:0.08 and placed in a ball mill, using zirconium oxide as ball milling balls and a ball-to-material ratio of 20:1, and ball milling was carried out at a speed of 200 rpm for 30 minutes to prepare a primary mixture, and the primary mixture was mixed with deionized water to prepare a suspension with a solid-liquid ratio of 0.1 g / mL, and the suspension was spray-dried in a spray drying equipment at an inlet air temperature of 165° C. to obtain a mixed phosphor;

[0086] S1. After γ-aminopropyltriethoxysilane (KH-550) was diluted with anhydrous ethanol to prepare a γ-aminopropyltriethoxysilane solution with a concentration of 23%, the mixed phosphor was added to the γ-aminopropyltriethoxysilane solution (the mass ratio of the mixed phosphor to γ-aminopropyltriethoxysilane was 1:0.24), and ultrasonically mixed for 15 minutes in a 35°C water bath environment and an ultrasonic frequency of 25 kHz. The mixture was then filtered under reduced pressure and dried in a vacuum drying oven at 60°C to constant weight to obtain a surface-activated mixed phosphor. The surface-activated mixed phosphor was mixed with ethyl orthosilicate in a mass ratio of 1:2.5, kept warm in a 40°C water bath environment and ultrasonically mixed at 20 kHz for 5 minutes, kept warm for 30 minutes, filtered under reduced pressure, and rinsed three times with deionized water and anhydrous ethanol. The mixture was then dried in a vacuum drying oven at 75°C to constant weight to obtain a modified mixed powder.

[0087] S2. γ-aminopropyltrimethoxysilane was diluted with anhydrous ethanol to prepare a 20% γ-aminopropyltrimethoxysilane solution, which was then treated at a constant temperature in a 70°C water bath. The modified mixed powder was preheated in a 70°C vacuum environment for 1 hour, and the preheated modified mixed powder was mixed with the γ-aminopropyltrimethoxysilane solution (the mass ratio of the modified mixed powder to γ-aminopropyltrimethoxysilane was 1:0.25). The mixture was ultrasonically mixed at 25 kHz in a 70°C water bath for 5 minutes, kept warm for 1 hour, and filtered under reduced pressure. The mixture was then rinsed three times with deionized water and anhydrous ethanol, and dried in a 55°C vacuum drying oven to constant weight to obtain the modified phosphor.

[0088] Comparative Example 1

[0089] This comparative example 1 provides a method for preparing a mixed phosphor powder, comprising the following steps: preparing a fluorescent blue powder (Sr5(PO4)3Cl:Eu 2+ )、Fluorescent red powder((Ca,Sr)AlSiN3:Eu 2+ )、Phosphor Blue Powder((Ba,Sr)5(PO4)3Cl:Eu 2+ ) and fluorescent yellow-green powder (Y3Ga 2.5 Al 2.5 O 12 :Ce 3+ ) were mixed in a mass ratio of 1:0.25:0.17:0.08 and put into a ball mill, zirconium oxide was used as the ball milling balls, the ball-to-material ratio was 20:1, and the ball milling was carried out at a speed of 200 rpm for 30 minutes to obtain a primary mixture, which was mixed with deionized water to prepare a suspension with a solid-liquid ratio of 0.1 g / mL, and the suspension was spray-dried in a spray drying equipment at an inlet air temperature of 165°C to obtain a mixed phosphor.

[0090] Comparative Example 2

[0091] This comparative example 2 provides a method for preparing a modified phosphor, comprising the following steps:

[0092] S0, fluorescent blue powder (Sr5(PO4)3Cl:Eu 2+ )、Fluorescent red powder((Ca,Sr)AlSiN3:Eu 2+ )、Phosphor Blue Powder((Ba,Sr)5(PO4)3Cl:Eu 2+ ) and fluorescent yellow-green powder (Y3Ga 2.5 Al 2.5 O 12 :Ce 3+ ) were mixed in a mass ratio of 1:0.25:0.17:0.08 and placed in a ball mill, using zirconium oxide as ball milling balls and a ball-to-material ratio of 20:1, and ball milling was carried out at a speed of 200 rpm for 30 minutes to prepare a primary mixture, and the primary mixture was mixed with deionized water to prepare a suspension with a solid-liquid ratio of 0.1 g / mL, and the suspension was spray-dried in a spray drying equipment at an inlet air temperature of 160° C. to obtain a mixed phosphor;

[0093] S1. After diluting γ-aminopropyltrimethoxysilane with anhydrous ethanol to prepare a 20% γ-aminopropyltrimethoxysilane solution, the mixed phosphor is added to the γ-aminopropyltrimethoxysilane solution (the mass ratio of the mixed phosphor to γ-aminopropyltrimethoxysilane is 1:0.23), ultrasonically mixed for 15 minutes in a 35°C water bath environment and an ultrasonic frequency of 25 kHz, filtered under reduced pressure and dried in a 55°C vacuum drying oven to constant weight to obtain a surface-activated mixed phosphor; the surface-activated mixed phosphor is mixed with ethyl orthosilicate in a mass ratio of 1:2.5, kept warm in a 40°C water bath environment and ultrasonically mixed at 20 kHz for 5 minutes, kept warm for 30 minutes and filtered under reduced pressure, rinsed three times with deionized water and anhydrous ethanol, and dried in a 75°C vacuum drying oven to constant weight to obtain a modified phosphor.

[0094] Comparative Example 3

[0095] This comparative example 3 provides a method for preparing a modified phosphor, comprising the following steps:

[0096] S0, fluorescent blue powder (Sr5(PO4)3Cl:Eu 2+ )、Fluorescent red powder((Ca,Sr)AlSiN3:Eu 2+ )、Phosphor Blue Powder((Ba,Sr)5(PO4)3Cl:Eu 2+ ) and fluorescent yellow-green powder (Y3Ga 2.5 Al 2.5 O 12 :Ce 3+) were mixed in a mass ratio of 1:0.25:0.17:0.08 and placed in a ball mill, using zirconium oxide as ball milling balls and a ball-to-material ratio of 20:1, and ball milling was carried out at a speed of 200 rpm for 30 minutes to prepare a primary mixture, and the primary mixture was mixed with deionized water to prepare a suspension with a solid-liquid ratio of 0.1 g / mL, and the suspension was spray-dried in a spray drying equipment at an inlet air temperature of 160° C. to obtain a mixed phosphor;

[0097] S1. γ-aminopropyltrimethoxysilane was diluted with anhydrous ethanol to prepare a 20% γ-aminopropyltrimethoxysilane solution, which was then treated at a constant temperature in a 70°C water bath. The mixed phosphor was preheated in a 70°C vacuum environment for 1 hour, and the preheated mixed phosphor was mixed with the γ-aminopropyltrimethoxysilane solution (the mass ratio of the mixed phosphor to γ-aminopropyltrimethoxysilane was 1:0.25). The mixture was ultrasonically mixed at 25 kHz in a 70°C water bath for 5 minutes, kept warm for 1 hour, and filtered under reduced pressure. The mixture was then rinsed three times with deionized water and anhydrous ethanol, and dried in a 55°C vacuum drying oven to constant weight to obtain a modified phosphor.

[0098] Performance testing

[0099] The phosphors prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were respectively configured as phosphor encapsulation compounds, which included, by mass, 2.5 parts of phosphors (Examples 1 to 3 and Comparative Examples 1 to 3), 7 parts of acrylic resin (purchased from Shandong Qilin Chemical Co., Ltd.), 0.5 parts of silicone defoaming agent (purchased from Hebei Zhongchuang Bioengineering Co., Ltd.), 0.5 parts of antioxidant 1010, and 0.5 parts of calcium stearate.

[0100] The fluorescent packaging adhesive corresponding to Examples 1 to 3 is used to encapsulate blue light chips respectively, and the main wavelength of the first blue light chip is 437.5nm, the main wavelength of the second band blue light chip is 452.5nm, and the main wavelength of the third band blue light chip is 467.5nm, thereby preparing the three blue light full-spectrum LED light beads of Application Examples 1 to Application Examples 3; the corresponding fluorescent packaging adhesive in Example 1 is used to encapsulate three identical blue light chips with a main wavelength of 450-452.5nm to prepare the three blue light full-spectrum LED light beads of Application Example 4.

[0101] The fluorescent packaging glue corresponding to Comparative Examples 1 to Comparative Examples 3 is respectively packaged for the first blue light chip with a main wavelength of 437.5nm, the second blue light chip with a main wavelength of 452.5nm, and the third blue light chip with a main wavelength of 467.5nm, to obtain the three blue light full-spectrum LED beads of Application Examples 5 to Application Examples 7.

[0102] The three blue full-spectrum LED beads in Application Examples 1 to 4 were tested for color rendering index (CRI) based on the "T / SZSA 024.1-2019 Indoor Healthy Lighting Design Specification Part 1: Full-spectrum Technical Requirements". The values ​​of Ra, Re, and R1-R15 are shown in Table 1 below, where Ra is the average of R1-R8, and Re is the average of R1-R15.

[0103] The three-blue full-spectrum LED beads prepared in Application Examples 1 to 3 and Application Examples 5 to 7 were continuously illuminated for 24×30 hours in a 60°C environment for photothermal aging tests. The brightness attenuation rate of the LED beads before and after photothermal aging is shown in Table 2 below.

[0104] Table 1 Full spectrum Ra and R1 to R15 color rendering test

[0105] CRI color Application Example 1 Application Example 2 Application Example 3 Application Example 4 Ra 98.67 98.57 99.02 98.28 Re 98.29 98.32 98.59 97.11 R1 Light grayish red 99.8 99.2 99.86 98.15 R2 Dark grayish yellow 99.42 99.14 99.9 99.47 R3 saturated yellow-green 99.01 99.28 98.56 97.87 R4 Medium yellow-green 98.62 98.84 99.7 99.64 R5 light blue-green 99.46 99.13 99.72 98.18 R6 light blue 98.43 97.88 99.05 96.34 R7 lavender blue 97.96 97.98 98.49 98.36 R8 light red purple 96.62 97.14 96.87 98.2 R9 saturated red 92.99 94.56 93.16 99.39 R10 saturated yellow 99.15 99.12 98.81 99.07 R11 saturated green 98.48 98.27 98.99 97.28 R12 saturated blue 97.99 97.24 98.9 79.81 R13 Caucasian skin color 99.37 98.98 99.69 99.07 R14 Green leaves 98.83 98.9 98.49 98.65 R15 Yellow skin color 98.35 99.12 98.63 97.24

[0106] Table 2 Brightness decay rate

[0107] Brightness attenuation rate / % Brightness attenuation rate / % Application Example 1 0.53 Application Example 5 4.67 Application Example 2 0.48 Application Example 6 2.24 Application Example 3 0.55 Application Example 7 3.89

[0108] As can be seen from Table 1, after the phosphors in Examples 1 to 3 of the present invention are surface-modified and combined using three blue light chips with different peak wavelengths, the spectral continuity of the full spectrum can be significantly improved by supplementing the blue light wavelength (the wavelength of R12 saturated blue), so that the three blue light full-spectrum LED lamp beads provided by the present invention achieve a high color rendering index Ra average value greater than 98.5 and Re average value greater than 97.5, and the color rendering ability and enhanced color reproduction are significantly higher than those of Comparative Example 1.

[0109] As can be seen from Table 2, the three-blue full-spectrum LED light beads using the modified phosphors prepared in Examples 1 to 3 of the present invention can still maintain good brightness after the light-heat aging test. This shows that the modified phosphors provided by the present invention can significantly improve the durability of the LED light beads after the surface of the phosphors is modified with ethyl orthosilicate and treated with a silane coupling agent.

[0110] While the embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations of these embodiments are possible. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention as set forth in the claims. Furthermore, the invention described herein is susceptible to other embodiments and may be practiced or implemented in a variety of ways.

Claims

1. A three-blue full-spectrum LED lamp bead, characterized in that, It includes a first blue light chip with a peak wavelength of 460-465nm, a second blue light chip with a peak wavelength of 430-435nm, and a third blue light chip with a peak wavelength of 449-454nm; the first blue light chip, the second blue light chip, and the third blue light chip are excited and coupled to form full-spectrum white light after irradiating the fluorescent encapsulation layer; The fluorescent encapsulation layer is a cured modified fluorescent powder. The preparation method of the modified fluorescent powder comprises: ball milling and blending fluorescent blue powder, fluorescent red powder, fluorescent cyan powder and fluorescent yellow-green powder in a mass mixing ratio of 1:0.25:0.17:0.08 to obtain a primary mixture; ultrasonically mixing the primary mixture with deionized water to form a suspension, spray drying the suspension at 150-180° C. to obtain a mixed fluorescent powder; surface activating the mixed fluorescent powder in a silicon-containing active agent, wherein the silicon-containing active agent comprises diethylaminomethyltriethylamine. The invention relates to a method for preparing a modified phosphor powder comprising the following steps: preparing a phosphor powder comprising one of oxysilane, aniline methyl triethoxysilane, dichlorodimethylsilane, γ-aminopropyl trimethoxysilane and γ-aminopropyl triethoxysilane; stirring and mixing the surface-activated mixed phosphor in ethyl orthosilicate, separating and drying the mixed phosphor powder, and preserving the modified mixed powder at 60-80°C, mixing the modified mixed powder with a silane modifier, and ultrasonically reacting the mixed powder, separating and drying the mixed phosphor powder, wherein the mixed phosphor powder comprises fluorescent blue powder, fluorescent red powder, fluorescent cyan powder and fluorescent yellow-green powder; the fluorescent blue powder is Sr5(PO4)3Cl:Eu 2+ The fluorescent red powder is (Ca, Sr)AlSiN3:Eu 2+ The fluorescent blue powder is (Ba, Sr) 5 (PO 4 ) 3 Cl: Eu 2+ The fluorescent yellow-green powder is Y3Ga 2.5 Al 2.5 O 12 :Ce 3+ .

2. The lamp bead according to claim 1, characterized in that: The fluorescent encapsulation layer comprises modified fluorescent powder, resin and functional additives.

3. The lamp bead according to claim 2, characterized in that: When the surface-activated mixed phosphor is stirred and mixed in ethyl orthosilicate, the mass ratio of the mixed phosphor to the ethyl orthosilicate is 1:(2-3).

4. The lamp bead according to claim 2, characterized in that: The average particle size of the mixed phosphor is 5-10 μm.

5. The lamp bead according to claim 2, characterized in that: The surface activated mixed phosphor is stirred and mixed in ethyl orthosilicate at 35-45°C.

6. The lamp bead according to claim 2, characterized in that: The surface activated mixed phosphor is ultrasonically mixed in ethyl orthosilicate.

7. The lamp bead according to claim 2, characterized in that: When the modified mixed powder is obtained by separation and drying: the surface activated mixed phosphor is stirred and mixed in ethyl orthosilicate, and then the modified mixed powder is separated by filtration under reduced pressure and dried.

8. The lamp bead according to claim 2, characterized in that: After separation, the mixture is dried at 70-80° C. to obtain modified mixed powder.

9. The lamp bead according to claim 2, characterized in that: After separation, the modified mixed powder is obtained by drying in a vacuum environment.

10. The lamp bead according to claim 2, characterized in that: After separation, the modified mixed powder is obtained by rinsing with deionized water and anhydrous ethanol in a cycle and then drying.

11. The lamp bead according to claim 2, characterized in that: The modified mixed powder is kept at 60-80° C. and then mixed with a silane modifier for ultrasonic reaction: the silane modifier includes one of diethylaminomethyltriethoxysilane, anilinemethyltriethoxysilane, dichlorodimethylsilane, γ-aminopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane.

12. The lamp bead according to claim 2, characterized in that: The mass ratio of the modified mixed powder to the silane modifier is 1:(0.2-0.3).

13. The lamp bead according to claim 2, characterized in that: After the silane modifier is dissolved in an organic solvent to prepare a silane solution, the modified mixed powder is kept warm at 60-80° C. and then put into the silane solution for mixing and ultrasonic reaction.

14. The lamp bead according to claim 2, characterized in that: The modified mixed powder is kept warm in a vacuum environment at 60-80°C.

15. The lamp bead according to claim 2, characterized in that: The modified mixed powder is kept at 60-80° C. and then mixed with a silane modifier, and then subjected to ultrasonic mixing reaction at a frequency of 20-30 kHz.

16. The lamp bead according to claim 2, characterized in that: When the modified phosphor is prepared by separation and drying: after mixing and ultrasonic reaction, the modified phosphor is prepared by vacuum filtration and drying.

17. The lamp bead according to claim 2, characterized in that: After separation, the modified phosphor is dried at 40-60° C.

18. The lamp bead according to claim 2, characterized in that: After separation, the modified phosphor is dried in a vacuum environment.

19. The lamp bead according to claim 2, characterized in that: After separation, the modified phosphor is prepared by cyclically washing with deionized water and anhydrous ethanol and then drying.

20. The lamp bead according to any one of claims 2 to 19, characterized in that: The fluorescent encapsulation layer comprises 2-3 parts of modified fluorescent powder, 6-8 parts of resin and 1-2 parts of functional additives in parts by mass.

21. The lamp bead according to any one of claims 2 to 19, characterized in that: The resin includes one of phenyl vinyl silicone resin, acrylic resin and alicyclic epoxy resin.

22. The lamp bead according to any one of claims 2 to 19, characterized in that: The functional additives include a defoaming agent, an antioxidant, and a lubricant, and the defoaming agent includes one of a silicone defoaming agent and an acrylate defoaming agent, the antioxidant includes one of antioxidant 1010 and a phosphite, and the lubricant includes one of stearic acid, calcium stearate, and zinc stearate.

23. The lamp bead according to claim 1, characterized in that: After the first blue light chip, the second blue light chip and the third blue light chip irradiate the fluorescent packaging layer and are excited and coupled into full-spectrum white light, the wavelength difference between the three blue lights in the full-spectrum white light is 3-4%.

24. The lamp bead according to claim 1, characterized in that: The relative spectral intensity of blue light of the first blue light chip, the second blue light chip and the third blue light chip is 0.6-1.

2.

25. The lamp bead according to claim 1, characterized in that: The peak wavelength of the fluorescent red powder is 645-655 nm.

26. The lamp bead according to claim 1, characterized in that The peak wavelength of the fluorescent cyan powder is 490-495 nm.

27. The lamp bead according to claim 1, characterized in that: The peak wavelength of the fluorescent blue powder is 495-500nm.

28. The lamp bead according to claim 1, characterized in that: The peak wavelength of the fluorescent yellow-green powder is 520-540 nm.

29. The lamp bead according to claim 1, characterized in that: The red fluorescent powder includes europium-doped nitride fluorescent powder.

30. The lamp bead according to claim 1, characterized in that: The fluorescent cyan powder includes chlorophosphate fluorescent powder.

31. The lamp bead according to claim 1, characterized in that: The fluorescent blue powder includes chlorophosphate fluorescent powder.

32. The lamp bead according to claim 1, characterized in that The fluorescent yellow-green powder includes aluminate yellow-green powder.