An LED lamp bead and an LED light source

Abstract

This application provides an LED lamp bead and an LED light source, belonging to the field of LED technology. It includes: a substrate; at least one blue LED chip located on the substrate; and a phosphor layer located on the substrate and the blue LED chip. The phosphor layer contains a first nitride red phosphor, a second nitride red phosphor, a fluoride red phosphor, a green phosphor, and a yellow-green phosphor. The peak wavelength of the fluoride red phosphor is greater than the peak wavelength of the first nitride red phosphor and less than the peak wavelength of the second nitride red phosphor. This allows the LED lamp bead to achieve both a high color rendering index and good luminous efficiency.

Description

Technical Field

[0001] This application relates to the field of LED technology, specifically to an LED lamp bead and an LED light source. Background Technology

[0002] Potassium manganese fluorosilicate phosphor (KSF phosphor) is a high-performance narrow-band red phosphor material. When excited, KSF phosphor emits light through narrow-band emission, which can reduce spectral loss and improve blue light conversion efficiency, thereby effectively improving the luminous efficiency of LED chips. Therefore, it is currently widely used in the field of LED chips.

[0003] However, because KSF phosphor has a small half-width, it emits a narrow peak of red light only around 630nm, which results in insufficient spectral coverage of the emitted light and an inability to achieve a high color rendering index. As a result, KSF phosphor performs poorly when applied to ultra-high color rendering lighting products, especially low color temperature products. Summary of the Invention

[0004] In view of this, the embodiments of this application aim to provide an LED lamp bead and an LED light source to solve the problem in the prior art that the light emitted by KSF phosphor after activation has insufficient spectral coverage, resulting in a low color rendering index.

[0005] This application provides an LED lamp bead, including: substrate; At least one blue LED chip is located on the substrate; and, A phosphor layer is located on the substrate and the blue LED chip. The phosphor layer contains a first nitride red phosphor, a second nitride red phosphor, a fluoride red phosphor, a green phosphor, and a yellow-green phosphor. The peak wavelength of the fluoride red phosphor is greater than the peak wavelength of the first nitride red phosphor and less than the peak wavelength of the second nitride red phosphor.

[0006] In one embodiment, the peak wavelength of the first nitride red powder is 626nm~629nm, the peak wavelength of the second nitride red powder is 652.5nm~657.5nm, and the peak wavelength of the fluoride red powder is 630nm~631nm.

[0007] In one embodiment, the wavelength of the excitation light emitted by the blue LED chip is 450nm~452nm.

[0008] In one embodiment, the fluoride red powder has a mass percentage of 13.2% or greater in the phosphor layer.

[0009] In one embodiment, the first nitride red powder has a mass percentage of 0.1% to 2.1%, the second nitride red powder has a mass percentage of 0.3% to 2.5%, and the fluoride red powder has a mass percentage of 14.3% to 16.5%.

[0010] In one embodiment, the green powder has a mass percentage of 10% to 12%, the yellow-green powder has a mass percentage of 17% to 19%, and the adhesive material in the phosphor layer has a mass percentage of 52% to 54%.

[0011] In one embodiment, the ratio of the peak wavelength energy of the excitation light emitted by the blue LED chip to the peak wavelength energy of the output light generated after the fluoride red powder is excited is 1:3 to 1:4.

[0012] In one embodiment, the peak wavelength of the green powder is 507.5nm~512.5nm, and the peak wavelength of the yellow-green powder is 532.5nm~537.5nm.

[0013] In one embodiment, the peak wavelength of the first nitride red powder is 628 nm, the peak wavelength of the second nitride red powder is 655 nm, the peak wavelength of the fluoride red powder is 630 nm, the peak wavelength of the green powder is 510 nm, and the peak wavelength of the yellow-green powder is 535 nm.

[0014] This application provides an LED light source, including LED beads as described in any of the above embodiments.

[0015] This application sets the peak wavelength of the fluoride red phosphor between the peak wavelengths of the first nitride red phosphor and the second nitride red phosphor. This allows the fluoride red phosphor, upon excitation, to emit a narrow-peak red light near 630nm, improving the conversion efficiency of the excitation light emitted by the blue LED chip and reducing spectral loss in the LED's output light, thereby enhancing the LED's luminous efficiency. Simultaneously, the excitation of the first and second nitride red phosphors supplements the red light spectrum of the output light, compensating for the limitation of the fluoride red phosphor's narrow-peak red light emission only around 630nm, thus solving the problem of spectral deficiencies in the LED's output light and improving its color rendering index (CRI). Furthermore, the combination of the first and second nitride red phosphors with different peak wavelengths more closely approximates the optimal excitation wavelength of the red phosphor for the excitation light emitted by the blue LED chip, significantly improving excitation efficiency and further enhancing the LED's luminous efficiency. In short, this ensures that the LED achieves both a high CRI and high luminous efficiency. Furthermore, the light emitted by the green and yellow-green phosphors after being excited by the blue LED chip complements the spectral distribution of the green region, preventing spectral imbalance caused by the energy compression of the red region in the green region. This further ensures that the LED chip has a high color rendering index. Moreover, the combination of green and yellow-green phosphors more closely approximates the optimal excitation wavelength of the yellow phosphor by the blue LED chip, significantly improving excitation efficiency and thus luminous efficiency. In short, this ensures that the LED chip simultaneously achieves a high color rendering index and high luminous efficiency. Attached Figure Description

[0016] Figure 1 This is a light source spectrum test diagram of an LED lamp bead.

[0017] Figure 2 This is an energy test diagram for an LED light bead.

[0018] Figure 3 This is a schematic diagram of the structure of an LED lamp bead provided in an embodiment of this application.

[0019] Figure 4 An energy test diagram of an LED lamp bead provided in one embodiment of this application.

[0020] Figure 5 This is a comparison chart of energy tests for two types of LED beads.

[0021] Figure 6 This is a light source spectrum test diagram of an LED lamp bead provided in one embodiment of this application.

[0022] The attached figures are labeled as follows: 100 - Substrate; 101 - Blue LED chip; 102 - Phosphor layer. Detailed Implementation

[0023] Correlated Color Temperature (CCT), Color Rendering Index (CRI), and Luminous Efficiency are three important parameters describing the performance of LED light sources.

[0024] Color temperature is a physical quantity used to describe the color appearance of a light source. It is based on the properties of a thermally radiating blackbody and is expressed in absolute temperature (unit: Kelvin, K). The higher the color temperature, the closer the color of the light source is to blue (cool tone); the lower the color temperature, the closer the color of the light source is to red (warm tone). For example, the color temperature of daylight is typically between 5500K and 6500K, while the color temperature of warm white is typically between 2700K and 3500K.

[0025] The Color Rendering Index (CRI) is a measure of a light source's ability to reproduce the colors of an object. It is evaluated based on the difference in color between an object illuminated by a standard light source and the light source being tested. The CRI typically ranges from 0 to 100, with higher values ​​indicating that the light source can more accurately reproduce the true colors of an object.

[0026] Luminous efficiency is an indicator that measures the ability of a light source to convert energy into visible light. It reflects the electro-optical conversion efficiency of the light source. The higher the luminous efficiency, the higher the electro-optical conversion efficiency of the light source, which means that the light source has a higher ability to convert energy into visible light. The less energy is lost during the conversion process, and the more energy-efficient the light source is.

[0027] LED chips play a vital role in modern lighting and display applications. In recent years, with rapid technological advancements, the requirements for the color rendering index (CRI) and luminous efficiency of LED chips have become increasingly stringent. Current LED chips typically use potassium manganese fluorosilicate phosphor (KSF phosphor) to reduce spectral loss in emitted light and improve blue light conversion efficiency, thereby effectively enhancing the luminous efficiency of the chips. However, due to the relatively small half-width of KSF phosphor, emitting only a narrow peak of red light around 630nm, the spectral coverage of the emitted light is insufficient, failing to achieve a high CRI. Consequently, KSF phosphor performs poorly when applied to ultra-high CRI lighting products, especially low color temperature products.

[0028] Figure 1 This is a light source spectrum test diagram of an LED lamp bead. The phosphors used in this LED lamp bead include nitride red phosphor, fluoride red phosphor, and green phosphor. Specifically, the mass ratio of nitride red phosphor, fluoride red phosphor, green phosphor, and colloid is 0.07:0.43:0.05:1.2. (Refer to...) Figure 1 , Figure 1The horizontal axis represents wavelength (nm), and the vertical axis represents absolute spectrum (mW / nm). The absolute spectral peak of this LED bead exceeds 64mW / nm within the wavelength range of 620nm~680nm (i.e., the red light wavelength range). Furthermore, referring to Table 1, which shows the test results of the LED bead's color parameters, the color temperature was maintained at 2956K during the test. The color rendering index Ra of this LED bead was 97.0, the luminous flux Φ was 2205lm, the luminous efficacy was 141.51lm / W, and the electrical flux Φe was 7916mW.

[0029] Table 1: Photoelectric test results of an LED bead Furthermore, Figure 2 This is the energy test diagram for this LED chip. Figure 2 The horizontal axis represents wavelength, and the vertical axis represents energy value, such as... Figure 2 As shown, the energy value of this LED bead at its peak wavelength in the wavelength range of 430nm~480nm (i.e., the blue light wavelength range) is approximately 0.01773W / nm, and the energy value at its peak wavelength in the wavelength range of 620nm~680nm (i.e., the red light wavelength range) is approximately 0.049008W / nm. This is equivalent to the energy value of the KSF phosphor at its peak wavelength being approximately 0.049008W / nm. At this point, the ratio between the blue light peak wavelength energy value and the KSF phosphor peak wavelength energy value is approximately 2:5.

[0030] It is evident that this LED bead enhances the luminous efficacy in the red light wavelength range by using KSF phosphor. However, such LED beads typically require at least one additional phosphor to broaden the spectral range of the emitted light and improve the color rendering index, such as a red phosphor in the 650nm~660nm wavelength range and / or a green phosphor in the 500nm~510nm wavelength range. This can easily lead to a reduction in the amount of KSF phosphor used, resulting in a decrease in the ratio between the peak wavelength energy of blue light and the peak wavelength energy of KSF phosphor, thereby affecting the luminous efficiency of the LED bead.

[0031] In view of this, this application provides an LED lamp bead, comprising: a substrate; at least one blue LED chip located on the substrate; and a phosphor layer located on the substrate and the LED chip, wherein the phosphor layer contains a first nitride red phosphor, a second nitride red phosphor, a fluoride red phosphor, a green phosphor, and a yellow-green phosphor. Further, the peak wavelength of the fluoride red phosphor is greater than the peak wavelength of the first nitride red phosphor and less than the peak wavelength of the second nitride red phosphor. By setting the peak wavelength of the fluoride red phosphor between the peak wavelengths of the first and second nitride red phosphors, this application enables the fluoride red phosphor to emit narrow-peak red light near a wavelength of 630 nm after excitation, thereby improving the conversion efficiency of the excitation light emitted by the blue LED chip and reducing the spectral loss of the light emitted by the LED lamp bead, thus improving the luminous efficiency of the LED lamp bead. Meanwhile, the first and second nitride red powders, once excited, can supplement the red light spectrum of the output light, thereby compensating for the shortcoming of fluoride red powder, which only emits a narrow peak of red light near the wavelength of 630nm. This solves the problem of missing output light spectrum in LED chips and improves the color rendering index of LED chips.

[0032] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0033] In this application, the range of phosphor content, color temperature, and wavelength is represented as a~b, which means that the phosphor content, color temperature, or wavelength can be any value between a and b, including a and b.

[0034] Figure 3 This is a schematic diagram of the structure of an LED lamp bead provided in an embodiment of this application, referring to... Figure 3 The LED lamp beads provided in this application include a substrate 100, at least one blue LED chip 101, and a phosphor layer 102.

[0035] In one embodiment, the LED beads provided in this application can be packaged according to actual application requirements. For example, they can be COB packaging (Chip On Board) or SMD packaging (Surface Mount Device), but should not be limited thereto.

[0036] In one embodiment, the substrate 100 may be made of ceramic, metal, resin or composite materials.

[0037] In one embodiment, the blue LED chip 101 is located on the substrate 100. When setting the blue LED chip 101, the die bonding method can be selected according to the actual application requirements. For example, solder die bonding or surface mount die bonding can be selected, but it should not be limited to this.

[0038] In one embodiment, a phosphor layer 102 is located on the substrate 100 and the blue LED chip 101. The phosphor layer 102 contains a first nitride red phosphor, a second nitride red phosphor, a fluoride red phosphor, a green phosphor, and a yellow-green phosphor. Further, the phosphor layer 102 may also include an adhesive material, in which the first nitride red phosphor, the second nitride red phosphor, the fluoride red phosphor, the green phosphor, and the yellow-green phosphor are mixed. The first nitride red phosphor, the second nitride red phosphor, the fluoride red phosphor, the green phosphor, the yellow-green phosphor, and the adhesive material together constitute the phosphor layer 102.

[0039] The phosphor layer 102 can be obtained by dripping or spraying. The phosphor layer 102 needs to cover the blue LED chip 101 and output light under the excitation of the excitation light emitted by the blue LED chip 101.

[0040] In one embodiment, the peak wavelength of the green phosphor is 507.5 nm to 512.5 nm. Preferably, the peak wavelength of the green phosphor is 510 nm.

[0041] In one embodiment, the peak wavelength of the yellow-green phosphor is 532.5 nm to 537.5 nm. Preferably, the peak wavelength of the yellow-green phosphor is 535 nm.

[0042] In one implementation, the LED beads are low color temperature products. For example, the color temperature of the LED beads may be less than or equal to 4000K, but should not be limited to this.

[0043] Specifically, the output light spectrum of low color temperature LED chips has a very high proportion of red light and a very low proportion of blue and green light. To make the light emitted by the LED chip a warm yellow light (i.e., low color temperature), the energy of the light source will be concentrated in the red light region with a wavelength of 600nm~700nm. This will result in a significant compression of the energy in the green light region with a wavelength of 490nm~570nm. The light emitted by green phosphor with a peak wavelength of 507.5nm~512.5nm after being excited by excitation light can fill the spectral distribution of the wavelength range of 500nm~520nm. At the same time, the light emitted by yellow-green phosphor with a peak wavelength of 532.5nm~537.5nm after being excited by excitation light can further optimize the spectral distribution of the wavelength range of 530nm~550nm. This has almost no overlap with the spectral distribution of the light emitted by green phosphor, which has a significant effect on improving the spectral integrity of the light emitted by LED chips. Furthermore, the blue excitation light emitted by the blue LED chip 101 has the highest excitation efficiency for yellow phosphors with a wavelength of around 550nm. In other words, the excitation light emitted by the blue LED chip 101 has a higher excitation efficiency for yellow phosphors with a wavelength closer to 550nm. In this embodiment, the excitation efficiency is improved by setting a yellow-green phosphor with a peak wavelength close to 550nm, thereby improving the luminous efficiency. At the same time, green phosphor is set to supplement the spectral integrity of the output light, ensuring that the LED bead has a high color rendering index.

[0044] In one embodiment, the wavelength of the excitation light emitted by the blue LED chip 101 is 450nm~452nm. Specifically, the blue LED chip 101 used in the LED beads provided in this application embodiment can improve radiant energy compared with conventional blue LED chips with wavelengths greater than 452.5nm, especially improving the values ​​of color rendering index R6 (light blue) and R12 (saturated blue), which has a significant effect on improving the color rendering index of the LED beads.

[0045] In one embodiment, the ratio of the peak wavelength energy of the excitation light emitted by the blue LED chip 101 to the peak wavelength energy of the output light generated after the fluoride red powder is excited can be 1:3 to 1:4. In this way, the peak wavelength energy of the excitation light emitted by the blue LED chip 101 reaches a relatively high ratio to the peak wavelength energy of the output light generated after the fluoride red powder is excited, thereby improving the color rendering index and luminous efficiency of the LED chip, achieving better luminous effect and performance. For example, as shown... Figure 4 As shown, the LED beads provided in the embodiments of this application (such as...) Figure 4 (The yellow curve in the middle) and conventional LED beads (such as...) Figure 4Compared to the blue curve in the middle, the peak wavelength energy of the excitation light emitted by the blue LED chip 101 and the peak wavelength energy of the output light generated after the fluoride red powder is excited are both improved, and the ratio between the two is also improved compared to conventional LED beads.

[0046] Preferably, the ratio between the energy of the peak wavelength of the excitation light emitted by the blue LED chip 101 and the energy of the peak wavelength of the output light generated after the fluoride red powder is excited can be 1:4. Figure 5 As shown, using this LED bead as a test sample, the peak wavelength energy of the excitation light emitted by the blue LED chip 101 can reach 0.02095W / nm, and the peak wavelength energy of the output light generated after the fluoride red powder is excited can reach 0.083055W / nm.

[0047] In one embodiment, the peak wavelength of the fluoride red powder is greater than the peak wavelength of the first nitride red powder and less than the peak wavelength of the second nitride red powder.

[0048] Specifically, nitride red phosphor refers to a red phosphor whose composition is mainly composed of nitrides, such as a red phosphor doped with Eu ions and mainly composed of CaAlSiN3, or a red phosphor doped with Eu ions and mainly composed of Sr2Si5N8, but it should not be limited to these. Fluoride red phosphor refers to a red phosphor whose composition is mainly composed of fluorides, such as KSF phosphor (potassium fluorosilicate doped with manganese ions). In this embodiment, the composition of the first nitride red phosphor and the composition of the second nitride red phosphor can be set to be different, so that the peak wavelength of the first nitride red phosphor and the peak wavelength of the second nitride red phosphor are different. Furthermore, the peak wavelength of the fluoride red powder is greater than that of the first nitride red powder but less than that of the second nitride red powder. In other words, the peak wavelength of the fluoride red powder falls between the peak wavelengths of the first and second nitride red powders. As a result, when excited, the fluoride red powder can emit narrow-peak red light near 630nm, improving the conversion efficiency of the excitation light emitted by the blue LED chip and reducing spectral loss in the LED's emitted light, thereby increasing the luminous efficiency of the LED. Simultaneously, the excitation of the first and second nitride red powders can supplement the red light spectrum of the output light, thus compensating for the shortcoming of the fluoride red powder, which only emits narrow-peak red light near 630nm, solving the problem of spectral deficiencies in the LED's output light and further improving the color rendering index of the LED.

[0049] In one embodiment, the LED beads provided in this application are used as samples for testing, such as... Figure 6As shown, the absolute spectral peak value of this LED bead within the wavelength range of 620nm~680nm (i.e., the red light wavelength range) is approximately 109.5mW / nm. This indicates that the LED bead has better luminous efficacy in the red light spectrum and can achieve a higher color rendering index (CRI). Furthermore, referring to Table 2, which presents the test results of the color parameters of an LED bead provided in one embodiment of this application, the test color temperature was maintained at 2971K. The CRI Ra of the LED bead was 97.1, the luminous flux Φ was 2551lm, the luminous efficacy was 162.89lm / W, and the electrical flux Φe was 8117mW. It is evident that the LED bead provided in this embodiment exhibits good performance in both CRI and luminous efficacy, while simultaneously achieving a high CRI and luminous efficacy. Compared to conventional LED beads, the luminous efficacy is increased by 15.1% while maintaining the CRI.

[0050] Table 2: Test Results of Light Color Parameters of an LED Chip Provided in an Embodiment of this Application In one embodiment, the peak wavelength of the first nitride red phosphor is 626 nm to 629 nm. Preferably, the peak wavelength of the first nitride red phosphor is 628 nm.

[0051] In one embodiment, the peak wavelength of the second nitride red powder is 652.5 nm to 657.5 nm. Preferably, the peak wavelength of the second nitride red powder is 655 nm.

[0052] In one embodiment, the peak wavelength of the fluoride red powder is 630 nm to 631 nm. Preferably, the peak wavelength of the fluoride red powder is 630 nm.

[0053] Specifically, the first nitride red phosphor, once excited, supplements the red light output in the short wavelength range, while the second nitride red phosphor, once excited, supplements the red light output in the long wavelength range, thereby improving the spectral integrity of the LED chip's output light. Furthermore, the excitation light emitted by the blue LED chip 101 has the highest excitation efficiency for red phosphors with a peak wavelength of approximately 610 nm. In other words, the excitation light emitted by the blue LED chip 101 has higher excitation efficiency for red phosphors with wavelengths closer to 610 nm. In this embodiment, by setting a first nitride red phosphor with a peak wavelength close to 610 nm to improve excitation efficiency, thereby improving luminous efficiency, and simultaneously setting a second nitride red phosphor to supplement the spectral integrity of the output light, the LED chip is ensured to have a high color rendering index.

[0054] In one embodiment, the mass percentage of fluoride red powder in the phosphor layer 102 is greater than or equal to 13.2%. Exemplarily, the mass percentage of fluoride red powder in the phosphor layer 102 can be 13.2%, 15%, or 15.6%. Preferably, the mass percentage of fluoride red powder is 14.3% to 16.5%, for example, 14.3%, 15.5%, or 16.5%. Further, the mass percentage of fluoride red powder can be selected as 15.4%. This ensures a sufficient amount of fluoride red powder, avoiding the problem of insufficient fluoride red powder leading to a decrease in the ratio between the peak wavelength energy value of the blue LED chip 101 and the peak wavelength energy value of the KSF phosphor, thereby affecting the luminous efficiency of the LED.

[0055] In one embodiment, the mass percentage of the first nitride red powder is 0.1% to 2.1%. For example, the mass percentage of the first nitride red powder can be 0.1%, 0.6%, or 2.1%. Preferably, the mass percentage of the first nitride red powder can be 1%.

[0056] In one embodiment, the second nitride red powder has a mass percentage of 0.3% to 2.5%. For example, the mass percentage of the second nitride red powder can be 0.3%, 0.5%, or 2.5%. Preferably, the mass percentage of the first nitride red powder can be 1.4%.

[0057] In one embodiment, the mass percentage of green powder is 10% to 12%. Exemplarily, the mass percentage of green powder can be 10%, 11.5%, or 12%. Preferably, the mass percentage of green powder can be 11%.

[0058] In one embodiment, the mass percentage of the yellow-green powder is 17% to 19%. Exemplarily, the mass percentage of the yellow-green powder can be 17%, 18.5%, or 19%. Preferably, the mass percentage of the yellow-green powder can be 18.3%.

[0059] In one embodiment, the mass percentage of the adhesive material in the phosphor layer 102 is 52% to 54%. Exemplarily, the mass percentage of the adhesive material can be 52%, 53.6%, or 54%. Preferably, the mass percentage of the adhesive material can be 52.9%.

[0060] The technical solution of the present invention will be described below with reference to specific examples.

[0061] Exemplarily, this application provides an LED lamp bead, which includes a substrate 100, at least one blue LED chip 101, and a phosphor layer 102. The phosphor layer 102 includes a first nitride red phosphor, a second nitride red phosphor, a fluoride red phosphor, a green phosphor, a yellow-green phosphor, and a binder. The first nitride red phosphor has a peak wavelength of 628 nm and a mass percentage of 1%. The second nitride red phosphor has a peak wavelength of 655 nm and a mass percentage of 1.4%. The fluoride red phosphor has a peak wavelength of 630 nm and a mass percentage of 15.4%. The green phosphor has a peak wavelength of 510 nm and a mass percentage of 11%. The yellow-green phosphor has a peak wavelength of 535 nm and a mass percentage of 18.3%. The binder has a mass percentage of 52.9%. In this way, the mass ratio of the first nitride red powder, the second nitride red powder, the fluoride red powder, the green powder, the yellow-green powder, and the adhesive material can be: first nitride red powder: second nitride red powder: fluoride red powder: green powder: yellow-green powder: adhesive material = 0.045: 0.065: 0.7: 0.5: 0.83: 2.4.

[0062] The LED beads provided in Example 1 have the same effects as those described in any of the above embodiments, and will not be repeated here.

[0063] One embodiment of this application provides an LED light source, including LED beads as described in any of the above embodiments.

[0064] The LED light source provided in this application has the effect of LED lamp beads as described in any of the above embodiments, and will not be repeated here.

[0065] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.

[0066] It should also be noted that although preferred embodiments have been disclosed above, these embodiments are not intended to limit this application. Any person skilled in the art can make many possible variations and modifications to the technical solutions of this application, or modify them into equivalent embodiments, without departing from the scope of the technical solutions of this application. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this application, without departing from the content of the technical solutions of this application, shall still fall within the scope of protection of the technical solutions of this application.

[0067] It should also be understood that, unless otherwise specified or indicated, the terms “first,” “second,” “third,” etc., in the specification are used only to distinguish the various components, elements, and steps in the specification, and not to indicate the logical or sequential relationships between the various components, elements, and steps.

[0068] Furthermore, it should be recognized that the terminology described herein is used only to describe particular embodiments and is not intended to limit the scope of this application. It must be noted that the singular forms “a” and “an” as used herein include plural bases unless the context clearly indicates the opposite. For example, a reference to “a step” or “an apparatus” means a reference to one or more steps or apparatuses, and may include secondary steps and secondary apparatuses. All conjunctions used should be understood in the broadest sense. Also, the word “or” should be understood as having the definition of logical “or”, not logical “exclusive OR”, unless the context clearly indicates the opposite. Furthermore, implementations of the methods and / or devices in the embodiments of this application may include performing selected tasks manually, automatically, or in combination.

Claims

1. An LED lamp bead, characterized in that, include: substrate(100); At least one blue LED chip (101) is located on the substrate (100); and, A phosphor layer (102) is located on the substrate (100) and the blue LED chip (101). The phosphor layer (102) contains a first nitride red phosphor, a second nitride red phosphor, a fluoride red phosphor, a green phosphor, and a yellow-green phosphor. The peak wavelength of the fluoride red phosphor is greater than the peak wavelength of the first nitride red phosphor and less than the peak wavelength of the second nitride red phosphor.

2. The LED lamp bead according to claim 1, characterized in that, The peak wavelength of the first nitride red powder is 626nm~629nm, the peak wavelength of the second nitride red powder is 652.5nm~657.5nm, and the peak wavelength of the fluoride red powder is 630nm~631nm.

3. The LED lamp bead according to claim 1, characterized in that, The wavelength of the excitation light emitted by the blue LED chip (101) is 450nm~452nm.

4. The LED lamp bead according to any one of claims 1 to 3, characterized in that, The fluoride red powder has a mass percentage of 13.2% or greater in the phosphor layer (102).

5. The LED lamp bead according to claim 4, characterized in that, The first nitride red powder has a mass percentage of 0.1% to 2.1%, the second nitride red powder has a mass percentage of 0.3% to 2.5%, and the fluoride red powder has a mass percentage of 14.3% to 16.5%.

6. The LED lamp bead according to claim 5, characterized in that, The green powder has a mass percentage of 10% to 12%, the yellow-green powder has a mass percentage of 17% to 19%, and the adhesive material in the fluorescent powder layer (102) has a mass percentage of 52% to 54%.

7. The LED lamp bead according to any one of claims 1 to 3, characterized in that, The ratio of the peak wavelength energy of the excitation light emitted by the blue LED chip (101) to the peak wavelength energy of the output light generated after the fluoride red powder is excited is 1:3 to 1:

4.

8. The LED lamp bead according to claim 1, characterized in that, The peak wavelength of the green powder is 507.5nm~512.5nm, and the peak wavelength of the yellow-green powder is 532.5nm~537.5nm.

9. The LED lamp bead according to claim 1, characterized in that, The peak wavelength of the first nitride red powder is 628 nm, the peak wavelength of the second nitride red powder is 655 nm, the peak wavelength of the fluoride red powder is 630 nm, the peak wavelength of the green powder is 510 nm, and the peak wavelength of the yellow-green powder is 535 nm.

10. An LED light source, characterized in that, Includes LED beads as described in any one of claims 1 to 9.

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