Low-blue-light LED light source, preparation method thereof and lighting device

Abstract

The embodiment of the invention provides a low-blue-light LED light source, a preparation method thereof and a lighting device, the light source comprises a support, an LED chip arranged in the support and electrically connected with the support and a fluorescent layer packaging the chip, the fluorescent layer comprises a fluorescent powder composition, and the fluorescent powder composition comprises blue-green fluorescent powder, green fluorescent powder and red fluorescent powder; the LED chip is a purple light chip; the general chemical formula of the blue-green fluorescent powder is (Ba, Sr, Ca) < 1-x > Si2O2N2: xEu < 2 + >, the general chemical formula of the green fluorescent powder is (Lu, Ga) 3-yAl5O12: yCe < 3 + >, the chemical general formula of the red fluorescent powder is (Sr, Ca) (1-z) AlSiN3: zEu < 2 + > or (Sr, Ca) (2-z) Al2Si2N6: zEu < 2 + >. The light source can meet the requirement that the absolute spectral intensity of blue light in the range of 430-460 nm of the blue light band is lower than 0.1, and the requirement for healthy illumination is met.

Description

Technical Field

[0001] The embodiments of the present disclosure belong to the technical field of LED electronic packaging, and specifically relate to a low-blue light LED light source and a preparation method thereof, and a lighting device. Background Art

[0002] LED has the characteristics of long life, high luminous efficiency, good color rendering, safety and reliability, and rich colors. It is called the fourth generation of green light source and is widely used in lighting, backlighting and other special fields.

[0003] With the development of society, people have higher and higher requirements for the light quality of LED light sources. Conventional LED light sources are generally higher in the blue spectrum of 430nm to 460nm. Excessive blue light spectrum will inhibit the body's melatonin secretion, affecting the quality of people's rest. In addition, the blue light in this band poses a greater threat to the retina and endangers human health.

[0004] In view of the above problems, it is necessary to propose a low-blue light LED light source and a preparation method and a lighting device that are reasonably designed and effectively solve the above problems. Summary of the invention

[0005] The embodiments of the present disclosure aim to solve at least one of the technical problems existing in the prior art, and provide a low blue light LED light source and a preparation method thereof, and a lighting device.

[0006] One aspect of an embodiment of the present disclosure provides a low blue light LED light source, comprising: a bracket, an LED chip disposed in the bracket and electrically connected to the bracket, and a fluorescent layer encapsulating the LED chip, wherein the fluorescent layer comprises a fluorescent powder composition, and the fluorescent powder composition comprises a blue-green fluorescent powder, a green fluorescent powder, and a red fluorescent powder; wherein,

[0007] The LED chip uses a purple chip with a peak wavelength band of 400nm to 420nm;

[0008] The chemical formula of the blue-green phosphor is: (Ba, Sr, Ca) 1-x Si2O2N2:

[0009] x 2+ , the value range of x is 0.001≤x≤0.5, and the peak wavelength band of the blue-green phosphor is 480nm~500nm;

[0010] The chemical formula of the green phosphor is: (Lu, Ga) 3-y Al5O 12 :yCe 3+ , y has a value range of 0.001≤y≤0.5, and the peak wavelength of the green phosphor is in the range of 520nm to 580nm;

[0011] The chemical formula of the red phosphor is: (Sr, Ca) 1-z AlSiN3:zEu 2+ or (Sr,Ca) 2-z Al2Si2N6:zEu 2+ , the value range of z is 0.001≤z≤0.5, and the peak wavelength band of the red phosphor is 600nm~680nm.

[0012] Optionally, the blue-green fluorescent powder is: Ca 0.99 Si2O2N2:0.01Eu 2+ .

[0013] Optionally, the green phosphor is: Lu 2.96 Al5O 12 :0.04Ce 3+ .

[0014] Optionally, the red phosphor is: (Sr, Ca) 0.98 AlSiN3:0.02Eu 2+ .

[0015] Optionally, the phosphor composition includes 15 wt % to 25 wt % of cyan phosphor, 65 wt % to 82 wt % of green phosphor and 3 wt % to 10 wt % of red phosphor.

[0016] Optionally, the fluorescent layer further includes fluorescent glue, and the mass ratio of the fluorescent powder composition to the fluorescent glue is in the range of 1:(2-4).

[0017] Optionally, the light source further includes bonding wires, the bracket has positive and negative electrodes, and the LED chip is electrically connected to the positive and negative electrodes of the bracket via the bonding wires.

[0018] Optionally, the color rendering index Ra of the low blue light LED light source is greater than 80.

[0019] Another aspect of the embodiments of the present disclosure provides a lighting device, which includes the low blue light LED light source mentioned above.

[0020] Another aspect of the present disclosure provides a method for preparing a low blue light LED light source, the method comprising:

[0021] A bracket, an LED chip and a fluorescent layer are provided, wherein the fluorescent layer comprises a fluorescent powder composition, and the fluorescent powder composition comprises a blue-green fluorescent powder, a green fluorescent powder and a red fluorescent powder; wherein,

[0022] The LED chip uses a purple chip with a peak wavelength band of 400nm to 420nm;

[0023] The chemical formula of the blue-green phosphor is: (Ba, Sr, Ca) 1-x Si2O2N2:xEu 2+ , x ranges from 0.001≤x≤0.5, the luminescent peak wavelength of the blue-green phosphor is in the range of 480nm to 500nm; the chemical formula of the green phosphor is: (Lu, Ga) 3-y Al5O 12 :yCe 3+ , y ranges from 0.001≤y≤0.5, the peak wavelength of the green phosphor is 520nm to 580nm; the general chemical formula of the red phosphor is: (Sr, Ca) 1-z AlSiN3:zEu 2+ or (Sr,Ca) 2-z Al2Si2N6:zEu 2+ , the value range of z is 0.001≤z≤0.5, and the peak wavelength band of the red phosphor is 600nm~680nm;

[0024] The LED chip is arranged in the bracket and electrically connected to the bracket;

[0025] The fluorescent layer is filled in the bracket.

[0026] The low blue light LED light source of the disclosed embodiment and its preparation method and lighting device use a purple light chip with a peak wavelength band of 400nm to 420nm and blue-green powder phosphors, green phosphors and red phosphors of different wavelengths to match, so that the low blue light LED light source can meet the blue light band of 430nm to 460nm. The absolute spectral intensity of blue light is lower than 0.1, which meets the demand for healthy lighting and is very suitable for light sources in people's resting environments. The low blue light LED light source of this embodiment can not only solve the blue light hazard of ordinary LED light sources, but also has a certain color rendering index, and can be used as an excellent lighting source in a resting environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the structure of a low blue light LED light source in Example 1 of the disclosed embodiments;

[0028] Figure 2 This is a schematic diagram of the structure of a low blue light LED light source in Example 2 of the disclosed embodiments;

[0029] Figure 3 This is a spectrum data diagram of the low blue light LED light source in Example 3 of the disclosed embodiments;

[0030] Figure 4 This is a spectrum data diagram of the low blue light LED light source in Example 4 of the disclosed embodiments;

[0031] Figure 5 This is a spectrum data diagram of the low blue light LED light source in Example 5 of the disclosed embodiments. DETAILED DESCRIPTION

[0032] In order to enable those skilled in the art to better understand the technical solutions of the embodiments of the present disclosure, the embodiments of the present disclosure are further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0033] like Figure 1 and Figure 2 As shown, one aspect of the embodiment of the present disclosure provides a low blue light LED light source 100, including: a bracket 110, an LED chip 120 disposed in the bracket 110 and electrically connected to the bracket 110, and a fluorescent layer 130 encapsulating the LED chip 120, the fluorescent layer 130 includes a fluorescent powder composition, and the fluorescent powder composition includes a blue-green fluorescent powder, a green fluorescent powder, and a red fluorescent powder. Among them, the material of the bracket 110 includes but is not limited to PCT, EMC, etc., and can be selected according to actual needs.

[0034] The LED chip 120 uses a purple chip with a peak wavelength in the range of 400nm to 420nm. The number of the LED chips 120 is not specifically limited, and the number of the LED chips 120 can be as follows: Figure 1 As shown in FIG. 1, the number of LED chips 120 may also be as follows Figure 2 As shown, multiple LED chips 120 may be connected in series or in parallel. The number of LED chips 120 may be selected according to actual needs.

[0035] The chemical formula of blue-green phosphor is: (Ba, Sr, Ca) 1-x Si2O2N2:xEu 2+ , x has a value range of 0.001≤x≤0.5, and the luminescent peak wavelength of the blue-green powder phosphor is in the range of 480nm to 500nm. The blue-green powder phosphor can be selected from any of the substances shown in its chemical formula.

[0036] The chemical formula of green phosphor is: (Lu, Ga) 3-y Al5O 12 :yCe 3+ , y has a value range of 0.001≤y≤0.5, and the emission peak wavelength of the green phosphor is in the range of 520nm to 580nm. The green phosphor can be selected from any substance that meets the chemical formula.

[0037] The chemical formula of red phosphor is: (Sr, Ca) 1-z AlSiN3:zEu 2+ or (Sr,Ca) 2-z Al2Si2N6:zEu 2+ , the value range of z is 0.001≤z≤0.5, and the peak wavelength band of the red phosphor is 600nm~680nm. Among them, the red phosphor can be selected from any one of the substances in accordance with its chemical formula.

[0038] Specifically, the LED chip 120 is fixed on the bracket 110, and the LED chip 120 emits light after being powered on. Through the excitation of the purple light chip with a peak wavelength band of 400nm to 420nm and the combination of blue-green powder phosphor, green phosphor and red phosphor, the light color parameters of the LED light source meet the required color temperature, the color rendering index Ra reaches more than 80, the absolute spectral intensity of blue light in the range of 430nm to 460nm is lower than 0.1, and the peak intensity of 430nm to 460nm is higher than the peak intensity of the entire spectral region, so that the final color temperature of the LED light source is 3500K to 4500K.

[0039] The low blue light LED light source of the disclosed embodiment adopts a purple light chip with a peak wavelength band in the range of 400nm to 420nm and a combination of blue-green pink phosphors, green phosphors and red phosphors of different wavelengths. The low blue light LED light source can meet the blue light band of 430nm to 460nm with an absolute spectral intensity of less than 0.1, meeting the needs of healthy lighting. This low blue light LED light source can not only solve the blue light hazards of ordinary LED light sources, but also has a certain color rendering index, and can be used as an excellent lighting source in a rest environment.

[0040] Preferably, in this embodiment, the blue-green fluorescent powder can be: Ca 0.99 Si2O2N2:0.01Eu 2+ .

[0041] Preferably, in this embodiment, the green phosphor can be: Lu 2.96 Al5O 12 :0.04Ce 3+ .

[0042] Preferably, in this embodiment, the red phosphor can be: (Sr, Ca) 0.98 AlSiN3:0.02Eu 2+ .

[0043] Illustratively, in this embodiment, the phosphor composition includes 15 wt % to 25 wt % of cyan phosphor, 65 wt % to 82 wt % of green phosphor and 3 wt % to 10 wt % of red phosphor.

[0044] Exemplarily, the fluorescent layer 130 further includes fluorescent glue, and the mass ratio of the fluorescent powder composition to the fluorescent glue is in the range of 1:(2-4). The fluorescent glue may be organic silica gel for LED encapsulation.

[0045] Exemplarily, the low blue light LED light source 100 of the embodiment of the present disclosure further includes a bonding wire 140, the bracket 110 has positive and negative electrodes, and the LED chip 120 is electrically connected to the positive and negative electrodes of the bracket 110 through the bonding wire 140. The bonding wire 140 includes but is not limited to gold wire, silver wire, gold-silver alloy wire, copper wire, etc.

[0046] Another aspect of the present disclosure provides a lighting device, which includes the aforementioned low blue light LED light source 100. The specific structural features of the low blue light LED light source 100 have been described in detail above, and will not be repeated here.

[0047] The lighting device of the disclosed embodiment adopts the low blue light LED light source mentioned above, which can achieve that the low blue light LED light source meets the blue light band 430nm ~ 460nm range of blue light absolute spectral intensity is less than 0.1, meets the demand for healthy lighting, and is very suitable for the light source in the rest environment of people.

[0048] Another aspect of the present disclosure provides a method S100 for preparing a low blue light LED light source, the method S100 comprising:

[0049] S110, providing a bracket, an LED chip and a fluorescent layer, wherein the fluorescent layer comprises a fluorescent powder composition, and the fluorescent powder composition comprises a blue-green fluorescent powder, a green fluorescent powder and a red fluorescent powder; wherein,

[0050] The LED chip uses a purple chip with a peak wavelength band of 400nm to 420nm;

[0051] The chemical formula of the blue-green phosphor is: (Ba, Sr, Ca) 1-x Si2O2N2:xEu 2+ , x ranges from 0.001≤x≤0.5, the luminescent peak wavelength of the blue-green phosphor is in the range of 480nm to 500nm; the chemical formula of the green phosphor is: (Lu, Ga) 3-y Al5O 12 :yCe 3+, y ranges from 0.001≤y≤0.5, the peak wavelength of the green phosphor is 520nm to 580nm; the general chemical formula of the red phosphor is: (Sr, Ca) 1-z AlSiN3:zEu 2+ or (Sr,Ca) 2-z Al2Si2N6:zEu 2+ , the value range of z is 0.001≤z≤0.5, and the peak wavelength band of the red phosphor is 600nm~680nm.

[0052] Specifically, Figure 1 and Figure 2 As shown, a bracket 110, an LED chip 120 and a fluorescent layer 130 are provided. The material of the bracket 110 includes but is not limited to PCT, EMC, etc., and can be selected according to actual needs.

[0053] S120, placing the LED chip in the bracket and electrically connecting the LED chip to the bracket.

[0054] Specifically, Figure 1 and Figure 2 As shown, the LED chip 120 is disposed in the bracket 110 , and the LED chip 120 is electrically connected to the positive and negative electrodes of the bracket 110 through bonding wires 140 .

[0055] S130, filling the fluorescent layer into the bracket.

[0056] Specifically, Figure 1 and Figure 2 As shown, the fluorescent layer 130 is filled in the bracket 110. The LED chip 120 emits light after being powered on, and the light emitted by the LED chip 120 excites the fluorescent powder to form the required mixed light.

[0057] It should be noted that the fluorescent layer 130 includes fluorescent glue in addition to the fluorescent powder composition, and the mass ratio of the fluorescent powder composition to the fluorescent glue is in the range of 1:(2-4). The fluorescent glue can be organic silicone for LED packaging.

[0058] After the low blue light LED light source as described above is made, the light color parameters are tested with a photoelectric integrating sphere. The low blue light LED light source can meet the color rendering index Ra greater than 80, and the absolute spectral intensity of blue light in the range of 430nm to 460nm is less than 0.1, meeting the requirements of healthy lighting, and is very suitable for light sources in a resting environment.

[0059] The specific composition of the low blue light LED light source of the embodiment of the present disclosure is further explained below in conjunction with several specific embodiments.

[0060] Example 1

[0061] like Figure 1 As shown, this embodiment provides a low blue light LED light source 100, including a bracket 110, an LED chip 120 disposed in the bracket 110 and electrically connected to the bracket 110, and a fluorescent layer 130 encapsulating the LED chip 120, the fluorescent layer 130 including a fluorescent powder composition, the fluorescent powder composition including blue-green fluorescent powder, green fluorescent powder and red fluorescent powder. An LED chip 120 is fixed on the bracket 110, and the LED chip 120 emits light after being powered on, and the light emitted by the LED chip 120 excites the fluorescent layer 130 to form the required mixed light.

[0062] Example 2

[0063] like Figure 2 As shown, this embodiment provides a low blue light LED light source 100, including a bracket 110, a plurality of LED chips 120 arranged in the bracket 110 and electrically connected to the bracket 110, and a fluorescent layer 130 encapsulating the LED chips 120, and the plurality of LED chips 120 can be connected in series or in parallel. The fluorescent layer 130 includes a fluorescent powder composition, and the fluorescent powder composition includes blue-green fluorescent powder, green fluorescent powder and red fluorescent powder. The plurality of LED chips 120 are fixed on the bracket 110, and the plurality of LED chips 120 emit light after being powered on, and the fluorescent layer 130 excited by the light emitted by the LED chips 120 forms the required mixed light.

[0064] Example 3

[0065] In the low blue light LED light source in Example 3, the bracket 100 is a PCT bracket. The LED chip 120 is an LED purple light chip with a peak wavelength of 410nm. The phosphor composition includes 19% of blue-green phosphor, 75% of green phosphor and 5% of red phosphor. The blue-green phosphor is Ca 0.99 Si2O2N2:0.01Eu 2+ , its peak emission wavelength is 492nm; the green phosphor is Lu 2.96 Al5O 12 :0.04Ce 3+ , its peak emission wavelength is 530nm; the red phosphor is (Sr, Ca) 0.98 AlSiN3:0.02Eu 2+ , and its luminous peak wavelength is 625nm. Phosphor mixture: silica gel total amount = 1:2.1, wherein the silica gel is organic silica gel for LED packaging. The bonding wire 140 is a gold wire.

[0066] The low blue light LED light source obtained in Example 3 was tested for light color parameters using a photoelectric integrating sphere, and the following results were obtained: Figure 3Spectral data shown and optoelectronic data as described in Table 1.

[0067] Table 1 Photoelectric data of low blue light LED light source in Example 3

[0068] coordinate Color temperature (K) Ra R1 R2 R3 R4 R5 R6 0.3802，0.3823 4051 82.7 94.0 87.4 71.8 84.8 87.7 70.5 R7 R8 R9 R10 R11 R12 R13 R14 R15 84.2 80.9 64.1 62.2 75.2 21.0 92.0 83.7 91.4

[0069] As described above, in Example 3, the color temperature of the low blue light LED light source 100 is 4051K, and the spectrum of the low blue light LED light source 100 can meet the healthy lighting demand of the absolute spectral intensity of blue light in the range of 430nm to 460nm being less than 0.1, and can also meet the lighting demand of 80 color rendering for daily lighting.

[0070] Example 4

[0071] In the low blue light LED light source in Example 4, the bracket 100 is a PCT bracket. The LED chip 120 is a LED purple light chip with a peak wavelength of 410nm. The phosphor composition includes 21% of blue-green phosphor, 74% of green phosphor and 5% of red phosphor. The blue-green phosphor is Ca 0.99 Si2O2N2:0.01Eu 2+ , its peak emission wavelength is 492nm; the green phosphor is Lu 2.96 Al5O 12 :0.04Ce 3+ , its peak emission wavelength is 530nm; the red phosphor is (Sr, Ca) 0.98 AlSiN3:0.02Eu 2+ , and its peak wavelength is 625nm. Phosphor mixture: silica gel total amount = 1:2.3, wherein the silica gel is organic silica gel for LED packaging. The bonding wire 140 is a gold wire.

[0072] The low blue light LED light source obtained in Example 4 was tested for light color parameters using a photoelectric integrating sphere, and the following results were obtained: Figure 4 Spectral data shown and optoelectronic data as described in Table 2.

[0073] Table 2 Photoelectric data of low blue light LED light source in Example 4

[0074] coordinate Color temperature (K) Ra R1 R2 R3 R4 R5 R6 0.3755，0.3771 4145 82.8 93.8 87.4 72.0 85.0 87.4 70.5 R7 R8 R9 R10 R11 R12 R13 R14 R15 84.8 81.6 65.2 62.1 75.2 19.6 91.9 83.8 91.7

[0075] As described above, in Example 4, the color temperature of the low blue light LED light source 100 is 4145K, and the spectrum of the low blue light LED light source 100 can meet the healthy lighting demand of the absolute spectral intensity of blue light in the range of 430nm to 460nm being less than 0.1, and can also meet the lighting demand of 80 color rendering for daily lighting.

[0076] Example 5

[0077] In the low blue light LED light source in Example 5, the bracket 100 is a PCT bracket. The LED chip 120 is an LED purple light chip with a peak wavelength of 412nm. The phosphor composition includes 18% of blue-green phosphor, 75% of green phosphor and 6% of red phosphor. The blue-green phosphor is Ca 0.99 Si2O2N2:0.01Eu 2+ , its peak emission wavelength is 492nm; the green phosphor is Lu 2.98 Al5O 12 :0.02Ce 3+ , its peak emission wavelength is 530nm; the red phosphor is (Sr, Ca) 0.98 AlSiN3:0.02Eu 2+ , and its luminous peak wavelength is 625nm. Phosphor mixture: silica gel total amount = 1:2, wherein the silica gel is organic silica gel for LED packaging. The bonding wire 140 is a gold wire.

[0078] The low blue light LED light source obtained in Example 5 was tested for light color parameters using a photoelectric integrating sphere, and the following results were obtained: Figure 5 Spectral data shown and optoelectronic data as described in Table 3.

[0079] Table 3 Photoelectric data of low blue light LED light source in Example 5

[0080] coordinate Color temperature (K) Ra R1 R2 R3 R4 R5 R6 0.3847，0.3863 3958 81.3 88.6 84.8 71.3 83.1 80.3 65.3 R7 R8 R9 R10 R11 R12 R13 R14 R15 88.6 88.5 82.0 52.5 70.2 1.9 86.8 83.6 95.7

[0081] As described above, in Example 5, the color temperature of the low blue light LED light source 100 is 3958K, and the spectrum of the low blue light LED light source 100 can meet the healthy lighting demand of the absolute spectral intensity of blue light in the range of 430nm to 460nm being less than 0.1, and can also meet the lighting demand of 80 color rendering for daily lighting.

[0082] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the embodiments of the present disclosure, but the embodiments of the present disclosure are not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the embodiments of the present disclosure, and these modifications and improvements are also considered to be within the protection scope of the embodiments of the present disclosure.

Claims

1. A low blue light LED light source, characterized in that: include: A bracket, an LED chip disposed in the bracket and electrically connected to the bracket, and a fluorescent layer encapsulating the LED chip, wherein the fluorescent layer comprises a fluorescent powder composition, and the fluorescent powder composition comprises a blue-green fluorescent powder, a green fluorescent powder, and a red fluorescent powder; wherein, The LED chip uses a purple chip with a peak wavelength band of 400nm to 420nm; The chemical formula of the blue-green phosphor is: (Ba, Sr, Ca) 1-x Si2O2N2:xEu 2+ , the value range of x is 0.001≤x≤0.5, and the peak wavelength band of the blue-green phosphor is 480nm~500nm; The chemical formula of the green phosphor is: (Lu, Ga) 3-y Al5O 12 :yCe 3+ , y has a value range of 0.001≤y≤0.5, and the peak wavelength of the green phosphor is in the range of 520nm to 580nm; The chemical formula of the red phosphor is: (Sr, Ca) 1-z AlSiN3:zEu 2+ or (Sr,Ca) 2-z Al2Si2N6:zEu 2+ , the value range of z is 0.001≤z≤0.5, and the peak wavelength band of the red phosphor is 600nm~680nm.

2. The low blue light LED light source according to claim 1, characterized in that: The blue-green fluorescent powder is: Ca 0.99 Si2O2N2:0.01Eu 2+ .

3. The low blue light LED light source according to claim 1, characterized in that: The green phosphor is: Lu 2.96 Al5O 12 :0.04Ce 3+ .

4. The low blue light LED light source according to claim 1, characterized in that: The red phosphor is: (Sr, Ca) 0.98 AlSiN3:0.02Eu 2+ .

5. The low blue light LED light source according to any one of claims 1 to 4, characterized in that: The phosphor composition comprises 15 wt % to 25 wt % of cyan phosphor, 65 wt % to 82 wt % of green phosphor and 3 wt % to 10 wt % of red phosphor.

6. The low blue light LED light source according to any one of claims 1 to 4, characterized in that: The fluorescent layer also includes fluorescent glue, and the mass ratio of the fluorescent powder composition to the fluorescent glue is in the range of 1:(2-4).

7. The low blue light LED light source according to any one of claims 1 to 4, characterized in that: The light source further comprises bonding wires, the bracket has positive and negative electrodes, and the LED chip is electrically connected to the positive and negative electrodes of the bracket via the bonding wires.

8. The low blue light LED light source according to any one of claims 1 to 4, characterized in that: The color rendering index Ra of the low blue light LED light source is greater than 80.

9. A lighting device, characterized in that: The lighting device comprises the low blue light LED light source according to any one of claims 1 to 8.

10. A method for preparing a low blue light LED light source, characterized in that: The preparation method comprises: A bracket, an LED chip and a fluorescent layer are provided, wherein the fluorescent layer comprises a fluorescent powder composition, and the fluorescent powder composition comprises a blue-green fluorescent powder, a green fluorescent powder and a red fluorescent powder; wherein, The LED chip uses a purple chip with a peak wavelength band of 400nm to 420nm; The chemical formula of the blue-green phosphor is: (Ba, Sr, Ca) 1-x Si2O2N2:xEu 2+ , x ranges from 0.001≤x≤0.5, the luminescent peak wavelength of the blue-green phosphor is in the range of 480nm to 500nm; the chemical formula of the green phosphor is: (Lu, Ga) 3-y Al5O 12 :yCe 3+ , y ranges from 0.001≤y≤0.5, the peak wavelength of the green phosphor is 520nm to 580nm; the general chemical formula of the red phosphor is: (Sr, Ca) 1-z AlSiN3:zEu 2+ or (Sr,Ca) 2- z Al2Si2N6:zEu 2+ , the value range of z is 0.001≤z≤0.5, and the peak wavelength band of the red phosphor is 600nm~680nm; The LED chip is arranged in the bracket and electrically connected to the bracket; The fluorescent layer is filled in the bracket.

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