A solar LED device and a method for manufacturing the same

Abstract

The application discloses a sunlight LED device and a preparation method thereof, and relates to the technical field of wavelength conversion elements.The sunlight LED device provided by the application comprises a violet light chip and two layers of fluorescent glue on the surface of the violet light chip, wherein the first layer comprises three different red fluorescent powders, and the second layer comprises a light blue white powder, a light blue green powder, a yellow green fluorescent powder, an infrared fluorescent powder and a stabilizer.The mixed fluorescent glue is obtained by compounding specific fluorescent powders in specific proportions, the light spectrums emitted by different fluorescent powders in the mixed fluorescent glue are matched with each other, and finally the sunlight LED device provided by the application can utilize the interaction between the fluorescent powders, improve the color rendering property of the LED device, and has good similarity with the sunlight spectrum under different color temperatures (3000K-6000K).

Description

Technical Field

[0001] This invention relates to the field of wavelength conversion element technology, specifically to a solar LED device and its fabrication method. Background Technology

[0002] Natural light, also known as "natural light," is light that does not directly exhibit polarization. Light emitted directly from both natural and artificial light sources is natural light, encompassing all possible vibration directions perpendicular to the direction of light wave propagation, and therefore does not show polarization. Natural light emitted directly from ordinary light sources is a random collection of countless polarized rays, so it is impossible to detect any direction of intensity bias when observed directly. This type of light, where the intensity of light waves vibrating in all directions is the same, is called natural light. Natural light is full-spectrum illumination, which promotes the release of dopamine from the retina. Dopamine helps photoreceptor cells respond to light stimulation, inhibits axial elongation of the eye, and allows light to focus on the retina. A lack of natural light can lead to insufficient dopamine secretion from the retina, increasing the risk of myopia.

[0003] Traditional LED lighting sources mostly use a mixture of single-band blue light chips and YAG phosphors to produce white light, resulting in a narrow spectral range. To improve the similarity between the emission spectrum of LED devices and the solar spectrum, existing technologies disclose a natural health LED light source device and its preparation method. This involves preparing a composite phosphor by mixing light blue-white powder, light blue-green powder, yellow-green powder, orange-red powder, and white powder, and then coating it onto a near-ultraviolet light-emitting chip to obtain a white LED device. Although the spectrum produced by this LED light source is similar to natural light and has high continuity, the low coordination efficiency between the phosphors results in a significant difference between its emission spectrum and the solar spectrum, meaning the spectral gamut is not wide enough. Summary of the Invention

[0004] To address the problem that existing technologies cannot further improve the similarity between the spectrum of a solar LED device and the solar spectrum, this invention provides a solar LED device that uses a specific ratio of specific phosphors to obtain a mixed phosphor adhesive. By utilizing the interaction between the phosphors, the similarity between the spectrum of the LED device and the solar spectrum is improved.

[0005] Another object of the present invention is to provide a method for preparing a solar LED device.

[0006] The above-mentioned objective of this invention is achieved through the following technical solution:

[0007] A solar LED device includes a violet light chip and a mixed phosphor on the surface of the violet light chip;

[0008] The emission wavelength of the violet light chip is 400–420 nm;

[0009] The mixed fluorescent adhesive includes a first layer and a second layer sequentially stacked on the surface of the violet chip, wherein the first layer of fluorescent adhesive includes red phosphor, and the second layer of fluorescent adhesive includes light blue-white phosphor, light blue-green phosphor, yellow-green phosphor, infrared phosphor, and stabilizer.

[0010] The red phosphor includes a first, a second, and a third red phosphor;

[0011] The infrared phosphor includes a first infrared phosphor and a second infrared phosphor;

[0012] The emission wavelength range of the red phosphor is 600-680 nm, and the excitation wavelengths of the first, second and third red phosphors are 595-610 nm, 640-660 nm and 670-685 nm, respectively.

[0013] The light blue-white phosphor has an emission wavelength of 445–455 nm and an excitation wavelength of 440–455 nm.

[0014] The light blue-green phosphor has an emission wavelength of 495–500 nm and an excitation wavelength of 495–505 nm.

[0015] The yellow-green phosphor has an emission wavelength of 520–540 nm and an excitation wavelength of 525–535 nm.

[0016] The infrared phosphor has an emission wavelength of 700-840 nm, and the first and second infrared phosphors have excitation wavelengths of 760-780 nm and 795-805 nm, respectively. The mass ratio of each component in the mixed fluorescent adhesive is red phosphor: light blue-white phosphor: light blue-green phosphor: yellow-green phosphor: infrared phosphor: stabilizer = (2-7): (40-60): (10-15): (11-18): (11-22): (0.5-1.2).

[0017] In a specific embodiment of the present invention, the aforementioned solar LED device further includes a bowl-shaped support for carrying the chip; a mixed phosphor on the surface of the ultraviolet chip is coated onto the chip surface using a lamination and dispensing technique; the stabilizer is a white powder with the chemical formula C2H6Cl2O2Si2. The thickness of the phosphor layer in the solar LED device provided by the present invention is closely related to the bowl-shaped support used. In a specific embodiment of the present invention, the thickness of the first phosphor layer can be 0.02-0.06 nm; the thickness of the second phosphor layer can be 0.02-4.4 nm.

[0018] In this invention, a two-layer phosphor is coated on the surface of a violet light chip. This allows the first layer to be excited by the violet light chip, and the second layer of phosphor to be excited by the light emitted by the first layer of phosphor. The mass ratio of various phosphors is controlled as follows: red phosphor: light blue-white phosphor: light blue-green phosphor: yellow-green phosphor: infrared phosphor: stabilizer = (2-7): (40-60): (10-15): (11-18): (11-22): (0.5-1.2). This ensures that the spectra of different phosphors complement and interact with each other, thereby ensuring that the spectrum of the resulting LED device is close to the solar spectrum.

[0019] This invention employs three phosphors to blend and obtain the red phosphor in the mixed phosphor adhesive, while two phosphors are blended to obtain the infrared phosphor, both aimed at improving spectral continuity. Using only one phosphor as the red or infrared phosphor results in LED devices with poor spectral continuity, leading to a decrease in color rendering. In fact, the key to this invention lies in using different red and infrared phosphors in blending, while simultaneously adding light blue-white phosphors to harmonize the red light emitted by the first layer of phosphors.

[0020] Preferably, the mass ratio of each component in the red phosphor is: first red phosphor: second red phosphor: third red phosphor = (0.5~2.8): (1.8~4.0): (0.2~1.5).

[0021] Preferably, the mass ratio of each component in the infrared phosphor is: first infrared phosphor: second infrared phosphor = (10-20): (1-2).

[0022] Preferably, the relative brightness of the light blue-white phosphor is 80–120.

[0023] Preferably, the relative brightness of the light blue-green phosphor is 80–120.

[0024] Controlling relative brightness helps to improve the similarity between the LED device spectrum and the solar spectrum.

[0025] Preferably, the light blue-white phosphor is (Sr 1-x-y Ba y Eu x )5(PO4)3Cl, of which 0 <x<1,0<y<1,x+y<1。

[0026] Preferably, the light blue-green phosphor is a Lu-Ga eutectic.

[0027] Preferably, the yellow-green phosphor is (Y 1-x-y Lu x Gd y )3(Al 1-z Gaz )5O 12 :Ce, where 0 <x<1,0<y<1,x+y<1,0<z<1。

[0028] Preferably, the first, second, and third red phosphors are M3SiO5:Eu 2+ 、CaAlSiN3、CaAlSiN3.

[0029] More preferably, the first red phosphor M3SiO5:Eu 2+ M represents Sr.

[0030] Preferably, both the first and second infrared phosphors are (Ga,In)₂O₃:Cr 3+ The difference between the first and second infrared phosphors lies in the different ratios of Ga and In, which allows the two infrared phosphors to have different excitation wavelengths (760–780 nm and 795–805 nm, respectively).

[0031] This invention also protects the method for preparing the above-mentioned solar LED device, comprising the following steps:

[0032] S1. Use die-attach adhesive to fix the violet light chip onto the carrier surface, and dry it to ensure that the violet light chip is fixed;

[0033] S2. Connect the positive and negative electrodes of the violet light chip with a wire to conduct electricity;

[0034] S3. Apply the first layer of phosphor to the upper surface of the violet chip and the carrier surface, and bake at 90-110℃ for 0.5-2 hours; apply the second layer of phosphor to the surface of the first layer of phosphor; after coating, dry to ensure that the second layer of phosphor is cured, and the solar LED device can be obtained.

[0035] In a specific embodiment of the present invention, the carrier in step S1 can be a support bowl cup, and the wire in step S2 can be a gold wire.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] The solar LED device provided by this invention improves the similarity between the LED device and the solar spectrum by utilizing the interaction between specific phosphors. At color temperatures of 3000–6500 K, the solar LED device of this invention has a color rendering index (RA) ≥ 98. Attached Figure Description

[0038] Figure 1 This is a process flow diagram of the fabrication process of the solar LED device provided in Embodiment 1 of the present invention.

[0039] Figure 2This is a cross-sectional view of the solar LED device provided in Embodiment 1 of the present invention, wherein 001 is die bond adhesive, 002 is the bright silver layer at the bottom of the carrier, i.e., the support cup, 003 is the carrier and support cup of the LED device, 004 is the gold wire connecting the positive and negative electrodes of the violet chip, 005 is the violet chip, and 006 is the mixed phosphor.

[0040] Figure 3 The test spectrum of the solar LED device provided in Embodiment 1 of the present invention at a color temperature of 6500K and the solar spectrum at a color temperature of 6500K are shown.

[0041] Figure 4 This is a spectral test data diagram of a solar LED device provided in Embodiment 1 of the present invention.

[0042] Figure 5 The test spectrum of the solar LED device provided in Embodiment 2 of the present invention at a color temperature of 5000K and the solar spectrum at a color temperature of 5000K are shown.

[0043] Figure 6 This is a spectral test data diagram of a solar LED device provided in Embodiment 2 of the present invention.

[0044] Figure 7 The test spectrum of the solar LED device provided in Embodiment 3 of the present invention at a color temperature of 4000K and the solar spectrum at a color temperature of 4000K are shown.

[0045] Figure 8 This is a spectral test data diagram of a solar LED device provided in Embodiment 3 of the present invention.

[0046] Figure 9 The test spectrum of the solar LED device at a color temperature of 3000K and the solar spectrum at a color temperature of 3000K provided in Embodiment 4 of the present invention.

[0047] Figure 10 This is a spectral test data diagram of a solar LED device provided in Embodiment 5 of the present invention. Detailed Implementation

[0048] The present invention will be further described below with reference to specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise stated, the raw materials and reagents used in the embodiments of the present invention are conventionally purchased raw materials and reagents.

[0049] Example 1

[0050] A solar LED device includes a violet light chip and a mixed phosphor on the surface of the violet light chip;

[0051] The emission wavelength of the violet light chip is 400–420 nm;

[0052] The mixed fluorescent adhesive comprises two layers, wherein the first layer of fluorescent adhesive comprises red fluorescent powder, and the second layer of fluorescent adhesive comprises light blue-white fluorescent powder, light blue-green fluorescent powder, yellow-green fluorescent powder, infrared fluorescent powder, and stabilizer.

[0053] The red phosphor includes a first, a second, and a third red phosphor;

[0054] The infrared phosphor includes a first infrared phosphor and a second infrared phosphor;

[0055] The emission wavelength of the red phosphor is 600-680 nm, and the excitation wavelengths of the first, second and third red phosphors are 601 nm, 650 nm and 678 nm, respectively.

[0056] The light blue-white phosphor has an emission wavelength of 445–455 nm and an excitation wavelength of 448 nm.

[0057] The light blue-green phosphor has an emission wavelength of 495–500 nm and an excitation wavelength of 450 nm.

[0058] The yellow-green phosphor has an emission wavelength of 520–540 nm and an excitation wavelength of 528 nm.

[0059] The infrared phosphor has an emission wavelength of 700–840 nm, and the excitation wavelengths of the first and second infrared phosphors are 771 nm and 801 nm, respectively.

[0060] The mass ratio of each component in the mixed fluorescent adhesive is as follows: red phosphor: light blue-white phosphor: light blue-green phosphor: yellow-green phosphor: infrared phosphor: stabilizer = 3.32: 57.98: 13.51: 12.49: 11.91: 0.79;

[0061] The mass ratio of each component in the red phosphor is: first red phosphor: second red phosphor: third red phosphor = 0.76:2.24:0.32;

[0062] The mass ratio of each component in the infrared phosphor is 10.46:1.45 for the first infrared phosphor and 10.46 for the second infrared phosphor.

[0063] The first red phosphor, the second red phosphor, and the third red phosphor are M3SiO5:Eu 2+ CaAlSiN3, CaAlSiN3;

[0064] Both the first and second infrared phosphors are (Ga,In)₂O₃:Cr 3+ .

[0065] The above-mentioned light blue-white fluorescent powder is (Sr1-x-y Ba y Eu x )5(PO4)3Cl, relative brightness is 100;

[0066] The light blue-green phosphor mentioned above is a Lu-Ga eutectic with a relative brightness of 100.

[0067] The above-mentioned yellow-green phosphor is (Y 1-x-y Lu x Gd y )3(Al 1-z Ga z )5O 12 Ce, relative brightness is 112;

[0068] The method for fabricating a solar LED device provided in Example 1 above includes the following steps:

[0069] S1. Use die-attach adhesive to fix the violet light chip onto the carrier surface, bake at 100℃ for 30 minutes, and then bake at 175℃ for 1 hour to ensure the violet light chip is fixed;

[0070] S2. Gold wires are used to connect the positive and negative electrodes of the violet light chip for conductivity;

[0071] S3. Apply the first layer of phosphor to the surface of the UV chip and bake at 100°C for 1 hour; apply the second layer of phosphor to the surface of the first layer of phosphor; dry to ensure the second layer of phosphor is cured, and the solar LED device is obtained.

[0072] Example 2

[0073] A solar LED device, which differs from Embodiment 1 in that:

[0074] The mass ratio of each component in the mixed fluorescent adhesive is: red phosphor: light blue-white phosphor: light blue-green phosphor: yellow-green phosphor: infrared phosphor: stabilizer = 4.03: 54.08: 14.6: 13.3: 13.13: 0.86;

[0075] The mass ratio of each component in the red phosphor is: first red phosphor: second red phosphor: third red phosphor = 0.82:2.72:0.49;

[0076] The mass ratio of each component in the infrared phosphor is 11.35:1.78 for the first infrared phosphor and the second infrared phosphor.

[0077] Example 3

[0078] A solar LED device, which differs from Embodiment 1 in that:

[0079] The mass ratio of each component in the mixed fluorescent adhesive is as follows: red fluorescent powder: light blue-white fluorescent powder: light blue-green fluorescent powder: yellow-green fluorescent powder: infrared fluorescent powder: stabilizer = 5.28: 47.56: 12.6: 15.84: 17.84: 0.88;

[0080] The mass ratio of each component in the red phosphor is: first red phosphor: second red phosphor: third red phosphor = 1.28: 3.07: 0.93;

[0081] The mass ratio of each component in the infrared phosphor is 16.18:1.66 for the first infrared phosphor and 16.18 for the second infrared phosphor.

[0082] Example 4

[0083] A solar LED device, which differs from Embodiment 1 in that:

[0084] The mass ratio of each component in the mixed fluorescent adhesive is as follows: red phosphor: light blue-white phosphor: light blue-green phosphor: yellow-green phosphor: infrared phosphor: stabilizer = 7.02: 42.75: 13.74: 15.23: 18.88: 0.79;

[0085] The mass ratio of each component in the red phosphor is: first red phosphor: second red phosphor: third red phosphor = 2.05: 3.74: 1.23;

[0086] The mass ratio of each component in the infrared phosphor is 18.88:1.59 for the first infrared phosphor and the second infrared phosphor.

[0087] Performance testing

[0088] The natural health LED light source devices in Examples 1-4 were tested using an LED chip photoelectric testing system, and the test results are as follows: Figures 3-10 As shown in Table 1:

[0089] Table 1. Performance test data of the example

[0090] Example 1 6469 99.6 98.9 >98.7 >96.1 98.7 100.5 Example 2 5001 98.6 96.6 >97.8 >96.6 97 101.2 Example 3 4058 98.5 97.1 >97.1 >94.4 98.4 100.7 Example 4 3024 99.2 96.9 >98.2 >96.8 98.6 100.8

[0091] As can be seen from Table 1 above, the solar LED device provided by the present invention has good color rendering at different color temperatures. The color rendering index RA (average value of R1 to R8) can reach up to 99.6%, and Rf and Rg can also be increased to over 97% and 100.5% respectively. The resulting spectrum is closer to natural light.

[0092] Figure 1 This is a process flow diagram of the fabrication process of the solar LED device provided in Embodiment 1 of the present invention.

[0093] Figure 2 This is a cross-sectional view of the solar LED device provided in Embodiment 1 of the present invention, wherein 001 is die bond adhesive, 002 is the bright silver layer at the bottom of the carrier, i.e., the support cup, 003 is the carrier and support cup of the LED device, 004 is the gold wire connecting the positive and negative electrodes of the violet chip, 005 is the violet chip, and 006 is the mixed phosphor.

[0094] Figure 3 The test spectrum of the solar LED device provided in Embodiment 1 of the present invention at a color temperature of 6500K and the solar spectrum at a color temperature of 6500K are shown. Figure 4 This is a spectral test data diagram of a solar LED device provided in Embodiment 1 of the present invention.

[0095] Figure 5 The test spectrum of the solar LED device provided in Embodiment 2 of the present invention at a color temperature of 5000K and the solar spectrum at a color temperature of 5000K are shown. Figure 6 This is a spectral test data diagram of a solar LED device provided in Embodiment 2 of the present invention.

[0096] Figure 7 The test spectrum of the solar LED device provided in Embodiment 3 of the present invention at a color temperature of 4000K and the solar spectrum at a color temperature of 4000K are shown. Figure 8 This is a spectral test data diagram of a solar LED device provided in Embodiment 3 of the present invention.

[0097] Figure 9 The test spectrum of the solar LED device provided in Embodiment 4 of the present invention at a color temperature of 3000K and the solar spectrum at a color temperature of 3000K are shown. Figure 10 This is a spectral test data diagram of a solar LED device provided in Embodiment 4 of the present invention.

[0098] from Figures 3-10 It can be seen that the solar LED devices provided in Embodiments 1 to 4 of the present invention all have excellent color rendering properties, and the obtained spectra are close to the solar spectrum.

[0099] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A solar LED device, characterized in that, This includes the violet light chip and the mixed fluorescent adhesive on the surface of the violet light chip; The emission wavelength of the violet light chip is 400–420 nm; The mixed fluorescent adhesive includes a first layer and a second layer sequentially stacked on the surface of the violet chip, wherein the first layer of fluorescent adhesive includes red phosphor, and the second layer of fluorescent adhesive includes light blue-white phosphor, light blue-green phosphor, yellow-green phosphor, infrared phosphor, and stabilizer. The red phosphor includes a first, a second, and a third red phosphor; The infrared phosphor includes a first infrared phosphor and a second infrared phosphor; The emission wavelength range of the red phosphor is 600-680 nm, and the excitation wavelengths of the first, second and third red phosphors are 595-610 nm, 640-660 nm and 670-685 nm, respectively. The light blue-white phosphor has an emission wavelength of 445–455 nm and an excitation wavelength of 440–455 nm. The light blue-green phosphor has an emission wavelength of 495–500 nm and an excitation wavelength of 495–505 nm. The yellow-green phosphor has an emission wavelength of 520–540 nm and an excitation wavelength of 525–535 nm. The infrared phosphor emits at a wavelength of 700–840 nm, and the first and second infrared phosphors are excited at wavelengths of 760–780 nm and 795–805 nm, respectively. The mass ratio of each component in the mixed fluorescent adhesive is as follows: red fluorescent powder: light blue-white fluorescent powder: light blue-green fluorescent powder: yellow-green fluorescent powder: infrared fluorescent powder: stabilizer = (2-7): (40-60): (10-15): (11-18): (11-22): (0.5-1.2).

2. The solar LED device as described in claim 1, characterized in that, The mass ratio of each component in the red phosphor is: first red phosphor: second red phosphor: third red phosphor = (0.5~2.8): (1.8~4.0): (0.2~1.5).

3. The solar LED device as described in claim 1, characterized in that, The mass ratio of each component in the infrared phosphor is: first infrared phosphor: second infrared phosphor = (10-20): (1-2).

4. The solar LED device as described in claim 1, characterized in that, The relative brightness of the light blue-white phosphor is 80-120.

5. The solar LED device as described in claim 1, characterized in that, The relative brightness of the light blue-green phosphor is 80-120.

6. The solar LED device as described in claim 1, characterized in that, The light blue-white phosphor is (Sr) 1-x- y Ba y Eu x )5(PO4)3Cl, of which 0 <x<1,0<y<1,x+y<1。 7. The solar LED device as described in claim 1, characterized in that, The light blue-green phosphor is a Lu-Ga eutectic.

8. The solar LED device as described in claim 1, characterized in that, The yellow-green phosphor is (Y 1-x-y Lu x Gd y )3(Al 1-z Ga z )5O 12 :Ce, where 0 <x<1,0<y<1,x+y<1,0<z<1。 9. The solar LED device as described in claim 1, characterized in that, The first, second, and third red phosphors are M3SiO5:Eu 2+ 、CaAlSiN3、CaAlSiN3.

10. A method for manufacturing a solar LED device according to any one of claims 1 to 9, characterized in that, Includes the following steps: S1. Use die-attach adhesive to fix the violet light chip onto the carrier surface, and dry it to ensure that the violet light chip is fixed; S2. Connect the positive and negative electrodes of the violet light chip with a wire to conduct electricity; S3. Apply the first layer of phosphor to the upper surface of the violet chip and the carrier surface, and bake at 90-110℃ for 0.5-2 hours; apply the second layer of phosphor to the surface of the first layer of phosphor; after coating, dry to ensure that the second layer of phosphor is cured, and the solar LED device can be obtained.

Images