LED light sources and lighting devices that resemble natural light

Abstract

The present application relates to the field of light sources and provides an LED light source and lighting device that are close to natural light. The LED light source includes a base, at least one light-emitting assembly mounted on the base, and an electrical connection member electrically connected to the light-emitting assembly. The light-emitting assembly includes at least three light-emitting units, each of which includes a blue light chip and a wavelength conversion element formed on the light-emitting side of the blue light chip. The peak wavelengths of at least two of the blue light chips in the same light-emitting assembly differ by 3 nm or more. The light emitted by all the light-emitting units in the same light-emitting assembly can be mixed to form near-natural light with a wavelength of 400-700 nm, and the near-natural light has an absolute spectral power of greater than 0.7 in the 640-700 nm wavelength band. The LED light source and lighting device provided herein can emit near-natural light with a saturated red light spectrum.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims priority to a Chinese patent application filed with the China Patent Office on November 21, 2022, bearing application number 202211456881.9 and entitled "LED light source and lighting device that is close to natural light," the entire contents of which are incorporated herein by reference.

[0002] The present application relates to the field of light source technology, and in particular to an LED light source and lighting device that is close to natural light. [Background technology]

[0003] LED light sources are popular due to their advantages of energy saving, environmental protection, and high brightness. However, the light emitted by conventional LED light sources always feels unnatural and uncomfortable to people. The main reasons for this are, first, that the red light spectrum in the light is too weak, causing the ciliary muscles to be constantly pulled forward, making the eyes prone to myopia. Second, compared to natural light that is comfortable to people, its spectrum is incomplete and its color rendering is poor.

[0004] In pursuit of a more comfortable lighting effect, many research units have been working on developing light sources that are closer to natural light, such as combining a blue light chip with fluorescent powder to produce a white light source, or mixing red, green, and blue primary color chips to produce white light. When using a blue light chip with fluorescent powder, the spectrum is still not ideal due to certain limitations on the wavelength range of the chip and the wavelength range of the fluorescent powder, and the proportion of blue light in particular is too high. When using a combination structure of red, green, and blue chips, white light is also generated, but the intensity is high only at the three central wavelengths, and the other wavelength bands are too low, resulting in a higher proportion of blue light.

[0005] In addition, white LED products use multiple fluorescent modules arranged on a large phosphor, each corresponding to a single wavelength, and matched with a blue light chip to generate different light through different fluorescent modules, which are then mixed to produce white light. This structure makes it difficult to achieve uniform light mixing, and it is extremely difficult to produce near-natural light. In addition, the structure is complex, large, and not suitable for practical use. Summary of the Invention [Problem to be solved by the invention]

[0006] The purpose of the present application is to provide an LED light source and lighting device that is close to natural light, which solves the technical problem that the spectrum of red light in the light beam of the prior art is too weak and the spectrum is incomplete. [Means for solving the problem]

[0007] The present application is thus realized, and in a first aspect, there is provided an LED light source that is close to natural light, comprising: a base; at least one light emitting assembly provided on the base; and an electrical connection member electrically connected to the light emitting assembly, wherein the light emitting assembly comprises at least three light emitting units, each of which comprises a blue light chip and a wavelength conversion element formed on the light emitting side of the blue light chip, wherein the peak wavelengths of at least two of the blue light chips located in the same light emitting assembly differ by 3 nm or more, and the light emitted by all of the light emitting units in the same light emitting assembly can be mixed to form near-natural light with a wavelength of 400-700 nm, and the absolute spectral power of the near-natural light in the wavelength band of 640-700 nm is greater than 0.7.

[0008] In one embodiment, the peak wavelengths of all the blue light chips located in the same light emitting assembly are different from each other, and the peak wavelength interval between any two of the blue light chips is 3 nm or more.

[0009] In one embodiment, each of the light emitting units can emit near-natural light with a wavelength of 400-700 nm.

[0010] In one embodiment, the wavelength converting element comprises a phosphor.

[0011] In one embodiment, a phosphor composition is mixed in the phosphor, and the phosphor composition comprises: a first fluorescent powder having an emission wavelength of 480-500 nm; a second fluorescent powder having an emission wavelength greater than 500 nm and less than 620 nm; a third fluorescent powder having an emission wavelength of 620 nm or more; The mass ratio of the first fluorescent powder to the second fluorescent powder to the third fluorescent powder is (15-70):(15-70):(13-70).

[0012] In one embodiment, the first phosphor comprises phosphor A, and the emission wavelength of the phosphor A is 488-492 nm; The second fluorescent powder includes fluorescent powder B, and the emission wavelength of the fluorescent powder B is 523-542nm; The third phosphors include phosphor C, phosphor D, phosphor E and phosphor F, of which the emission wavelength of phosphor C is 628-681nm, the emission wavelength of phosphor D is 718-722nm, the emission wavelength of phosphor E is 738-742nm, and the emission wavelength of phosphor F is 793-797nm.

[0013] In one embodiment, the first fluorescent powder, the second fluorescent powder and the third fluorescent powder are provided separately; The second phosphor B comprises phosphor B1 and phosphor B2, and the phosphor B1 has an emission wavelength of 523-527nm, and the phosphor B2 has an emission wavelength of 538-542nm. The mass ratio of the phosphor B1 to the phosphor B2 is (20-85):(10-85); The phosphor C in the third phosphor comprises phosphor C1, phosphor C2 and phosphor C3, and the phosphor C1 has an emission wavelength of 628-632nm, the phosphor C2 has an emission wavelength of 658-662nm and the phosphor C3 has an emission wavelength of 677-681nm. The mass ratio of the phosphor C1, the phosphor C2, the phosphor C3, the phosphor D, the phosphor E and the phosphor F is (3-35):(1-45):(3-60):(7-90):(7-60):(1-70).

[0014] In one embodiment, the third phosphor C, the first phosphor and the second phosphor form a first mixture; The third phosphors D, E and F form a second mixture; In the first mixture, the mass ratio of the fluorescent powder A to the fluorescent powder B to the fluorescent powder C is (10-80):(15-85):(1-40); In the second mixture, the mass ratio of the fluorescent powder D to the fluorescent powder E to the fluorescent powder F is (20-120):(10-90):(1-100); The first mixture and the second mixture are provided separately.

[0015] In one embodiment, the phosphor includes a first fluorescent part, a second fluorescent part, and a third fluorescent part arranged in order along the light emission direction, the first fluorescent part includes the first fluorescent powder, the second fluorescent part includes the second fluorescent powder, and the third fluorescent part includes the third fluorescent powder.

[0016] In one embodiment, the phosphor includes a fourth fluorescent section and a fifth fluorescent section arranged in order along the light emitting direction, the fourth fluorescent section including the first mixture, and the fifth fluorescent section including the second mixture.

[0017] In one embodiment, the refractive index of each fluorescent portion arranged along the light emitting direction increases in sequence.

[0018] In one embodiment, the thickness of each phosphor part is larger than the particle diameter of any one of the phosphor powders, but smaller than 1.5 times the particle diameter of the largest phosphor powder in the phosphor part.

[0019] In one embodiment, the thickness of the phosphor is 0.3 mm or less.

[0020] In one embodiment, the near-natural light has the following optical parameters: When the color temperature of the near-natural light is 2700K-3000K, the absolute spectral power in the 380-435nm wavelength band is less than 0.35, the absolute spectral power in the 435-475nm wavelength band is greater than 0.40, the absolute spectral power in the 475-492nm wavelength band is greater than 0.45, the absolute spectral power in the 492-577nm wavelength band is greater than 0.50, the absolute spectral power in the 577-597nm wavelength band is greater than 0.75, the absolute spectral power in the 597-622nm wavelength band is greater than 0.80, and the absolute spectral power in the 622-700nm wavelength band is greater than 0.80; When the color temperature of the near-natural light is 4000K-4200K, the absolute spectral power in the 380-435nm wavelength band is less than 0.40, the absolute spectral power in the 435-475nm wavelength band is less than 0.65, the absolute spectral power in the 475-492nm wavelength band is greater than 0.60, the absolute spectral power in the 492-577nm wavelength band is greater than 0.65, the absolute spectral power in the 577-597nm wavelength band is greater than 0.80, the absolute spectral power in the 597-622nm wavelength band is greater than 0.8, and the absolute spectral power in the 622-700nm wavelength band is greater than 0.80; When the color temperature of the near-natural light is 5500K-6000K, the absolute spectral power in the 380-435nm wavelength band is less than 0.45, the absolute spectral power in the 435-475nm wavelength band is less than 0.80, the absolute spectral power in the 475-492nm wavelength band is greater than 0.70, the absolute spectral power in the 492-577nm wavelength band is greater than 0.80, the absolute spectral power in the 577-597nm wavelength band is greater than 0.80, the absolute spectral power in the 597-622nm wavelength band is greater than 0.80, and the absolute spectral power in the 622-700nm wavelength band is greater than 0.70; When the color temperature of the near-natural light is less than 4000K, the absolute spectral power in the 380-435nm wavelength band is less than 0.40, the absolute spectral power in the 435-475nm wavelength band is less than 0.65, the absolute spectral power in the 475-492nm wavelength band is greater than 0.30, the absolute spectral power in the 492-577nm wavelength band is less than 0.7, the absolute spectral power in the 577-597nm wavelength band is less than 0.80, the absolute spectral power in the 597-622nm wavelength band is greater than 0.8, and the absolute spectral power in the 622-700nm wavelength band is greater than 0.80.

[0021] In one embodiment, the same light-emitting unit includes multiple blue light chips, and the peak wavelengths of all the blue light chips located in the same light-emitting unit are the same, or the difference in peak wavelengths of any two of the blue light chips is within a predetermined range.

[0022] In one embodiment, the blue light chip is flip-mounted on the surface of the base.

[0023] In one embodiment, the wavelength conversion element is a fluorescent film, which is formed on the light-emitting surface of the blue light chip by spraying.

[0024] In one embodiment, the blue light chip is mounted on the base by a CSP packaging process.

[0025] In one embodiment, the blue light chip is mounted face up on the surface of the base layer.

[0026] In one embodiment, the base is provided with reflective cups that correspond one-to-one to the light-emitting units, each of the light-emitting units is provided with a corresponding reflective cup in one-to-one correspondence, and the electrical connection member is formed on the surface of the base and connected to the blue light chip at the bottom of the reflective cup.

[0027] In one embodiment, a first package layer is filled between the blue light chip and the wavelength conversion element in each of the light emitting units; Alternatively, a first package layer is filled between the blue light chip and the wavelength conversion element in each of the light emitting units, and the light output surface of the wavelength conversion element is covered with a second package layer.

[0028] In one embodiment, the light emitting assembly includes three light emitting units spaced apart and distributed in a triangular pattern; Alternatively, all the light emitting units located in the same light emitting assembly are arranged along a straight line.

[0029] In one embodiment, the pitch between two adjacent light-emitting units is greater than the thickness of the phosphor.

[0030] In a second aspect, there is provided a lighting device including an LED light source that is close to natural light according to each of the above embodiments. [Effects of the Invention]

[0031] The technical effects of the first aspect of the present application over the prior art are as follows:

[0032] First, each light-emitting assembly in the natural light-like LED light source according to the embodiment of the present application combines at least three light-emitting units to obtain a full-color bionic spectrum that is closer to natural light. Compared with traditional white light illumination, the wavelengths of natural light are more complete, the relative spectral power of each wavelength band is closer to natural light, and the visual sensation is more comfortable.

[0033] Secondly, the absolute spectral power of red light is improved, and red light in the 640-700nm range in particular has the effect of promoting blood circulation in the eyes and preventing eye fatigue. At the same time, red light in the 640-700nm range is saturated, and does not constantly pull the ciliary muscle forward, shortening the eye axis and improving the health level of lighting that is closer to natural light.

[0034] Third, it adopts a combination of at least three light-emitting units, has a simple structure, and has good variable controllability during the debugging process, enabling the debugging of near-natural light. This solves the problem that the combination of multiple light-emitting elements cannot produce near-natural light, and the problem that the combination of blue light chips and fluorescent adhesives cannot obtain near-natural light.

[0035] Fourth, the peak wavelengths of at least two blue light chips 310 located in the same light-emitting assembly differ by more than 3 nm, reducing the blue light while improving the optical power of the blue light, solving the problem of low blue light that has long existed in near-natural light research, making the full-color bionic spectrum closer to real natural light, and further improving the color rendering index.

[0036] Fifth, the light emitting unit can adopt a micro-light emitting body that meets the performance requirements. The entire light source is a micro-lamp bead, and multiple lamp beads are arranged in any shape on the base of various lamps. Because of its small volume, it can be installed at any position on the base, making it flexible in application, and the light emission of the entire lamp is uniform, resulting in good lighting effects.

[0037] Sixth, when combining multiple light-emitting units, a packaging technique can be used in which each light-emitting unit has its own wavelength conversion element, enabling continuous, wide-spectrum color light to be realized, which is suitable for physiotherapy products and overcomes the technical bottleneck of single wavelength and narrow spectrum in industrial color light sources.

[0038] As can be understood, the beneficial effects of the second aspect may be referred to the relevant description of the first aspect, and will not be described here.

[0039] In order to more clearly explain the technical solutions of the embodiments of the present application, the following briefly introduces drawings that may be used in the description of the embodiments of the present application or the prior art. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can also obtain other drawings based on these drawings without any creative work. [Brief explanation of the drawings]

[0040] [Figure 1] 1 is a schematic diagram of the top view structure of an LED light source that is close to natural light according to one embodiment of the present application; [Figure 2] FIG. 2 is a schematic cross-sectional view of one light-emitting unit in FIG. [Figure 3] FIG. 3 is a comparison diagram of the spectrum formed by an LED light source close to natural light according to an embodiment of the present application and the spectrum formed by a normal light source, where (a) in FIG. 3 is the spectrum formed by an LED light source close to natural light according to an embodiment of the present application, and (b) in FIG. 3 is the spectrum formed by a normal light source. [Figure 4] FIG. 2 is a diagram showing the spectrum formed by each light-emitting unit in the light-emitting assembly used in the examples of the present application. [Figure 5] FIG. 2 is a comparative diagram of spectra generated by an LED light source similar to natural light according to an embodiment of the present application at different driving currents. [Figure 6] 1 is a schematic diagram of a side structure of a wavelength conversion element used in an example of the present application. [Figure 7]2 is a spectrum diagram of an LED light source close to natural light according to Example 1. FIG. [Figure 8] FIG. 10 is a spectrum diagram of an LED light source that is close to natural light according to Example 2. [Figure 9] FIG. 10 is a spectrum diagram of an LED light source that is close to natural light according to Example 3. [Figure 10] FIG. 10 is a spectrum diagram of an LED light source that is close to natural light according to Example 4. [Figure 11] FIG. 10 is a spectrum diagram of an LED light source that is close to natural light according to Example 5. [Figure 12] FIG. 10 is a spectrum diagram of an LED light source that is close to natural light according to Example 6. [Figure 13] FIG. 10 is a spectrum diagram of an LED light source that is close to natural light according to Example 7. [Figure 14] FIG. 13 is a spectrum diagram of an LED light source that is close to natural light according to Example 8. [Figure 15] 2 is a schematic cross-sectional view of a first fluorescent section used in an embodiment of the present invention. FIG. [Figure 16] 1 is a schematic diagram of the top structure of an LED light source that is close to natural light according to another embodiment of the present application. [Figure 17] FIG. 17 is a schematic cross-sectional view of one light-emitting unit in FIG. 16. [Figure 18] 1 is a schematic diagram of the top structure of an LED light source that is close to natural light according to another embodiment of the present application. [Figure 19] FIG. 19 is a schematic cross-sectional view of one light-emitting unit in FIG. 18. [Figure 20] FIG. 2 is a schematic diagram of the package structure of a single light-emitting unit used in one embodiment of the present application. [Figure 21] FIG. 10 is a schematic diagram of the package structure of a single light-emitting unit used in another embodiment of the present application. [Figure 22] FIG. 10 is a schematic diagram of the package structure of a single light-emitting unit used in another embodiment of the present application. [Figure 23] FIG. 10 is a schematic diagram of the package structure of a single light-emitting unit used in another embodiment of the present application. [Explanation of symbols]

[0041] 100: base, 200: electrical connection member, 300: light-emitting unit, 310: blue light chip, 320: wavelength conversion element, 321: first fluorescent part, 3211: colloid, 3212: fluorescent powder, 322: second fluorescent part, 323: third fluorescent part, 330: protective layer, 340: transparent packaging layer, 400: reflective cup, 500: first packaging layer, 600: second packaging layer, d1: thickness of fluorescent part, d2: particle size of fluorescent powder, d3: thickness of phosphor, d4: pitch between two adjacent light-emitting units. DETAILED DESCRIPTION OF THE INVENTION

[0042] Hereinafter, the embodiments of the present application will be described in detail, and examples of the embodiments are shown in the drawings, and the same or similar reference numerals throughout refer to the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are illustrative and are intended to explain the present application, but should not be understood as limiting the present application.

[0043] In the description of this application, the orientations or positional relationships indicated by the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," etc. are based on the orientations or positional relationships shown in the drawings, and are merely for the convenience and simplification of the description of this application, and do not indicate or imply that the specified device or element must have a specific orientation or be configured and operated in a specific orientation, and therefore should not be understood as a limitation on the application.

[0044] Additionally, the terms "first" and "second" are for descriptive purposes only and should not be understood as indicating or implying relative importance or the number of technical features shown. Thus, a feature qualified as "first" or "second" may explicitly or implicitly include one or more of the feature. In the description of this application, "plurality" means two or more, unless otherwise specified.

[0045] In this application, unless otherwise clearly specified or limited, the terms "attached," "communicating," "connecting," "fixed," etc. should be understood in a broad sense, and may refer to, for example, a fixed connection, a detachable connection, or an integral connection, a mechanical connection, an electrical connection, a direct connection, an indirect connection via an intermediate medium, an internal connection between two elements, or an interactive relationship between two elements. Those skilled in the art can understand the specific meanings of the above terms in this application according to specific circumstances.

[0046] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be described in more detail below with reference to the drawings and examples.

[0047] Technical terms explanation:

[0048] 1. Spectral power:

[0049] The spectrum emitted by a light source is usually not a single wavelength, but a mixture of radiation at many different wavelengths. The distribution of the spectral radiation of a light source according to wavelength order and the intensity of each wavelength is called the spectral power distribution of the light source.

[0050] The parameters for expressing the magnitude of spectral power can be divided into absolute spectral power and relative spectral power. Absolute spectral power distribution curve: This refers to the curve created by the absolute value of the light energy of each wavelength of spectral radiation. Relative spectral power distribution curve: This refers to a spectral power distribution curve obtained by comparing the energy of each wavelength in the light source radiation spectrum and normalizing it so that the radiation power is changed only within a specified range. The relative spectral power at the maximum radiation power is 1, and the relative spectral powers of all other wavelengths are less than 1.

[0051] 2.Color ratio:

[0052] Any white light is obtained by mixing the three primary colors of red, green, and blue in appropriate proportions. To express the relative proportions of each of the three primary colors R, G, and B in the total amount of white light, the chromaticity coordinates r, g, and b are introduced, where r=R / (R+G+B), g=G / (R+G+B), b=B / (R+G+B), r+g+b=1, and r, g, and b are the color ratio of red light, green light, and blue light, respectively.

[0053] As shown in FIGS. 1 and 2 , an embodiment of the present application provides an LED light source that emits near-natural light and is used in various lighting devices. The LED light source includes a base 100, at least one light-emitting assembly mounted on the base 100, and an electrical connector 200 electrically connected to the light-emitting assembly. The base 100 in this embodiment may be a rigid base such as a printed circuit base or an aluminum base, or a flexible base. The base 100 can be flexibly selected according to specific usage needs. The electrical connector 200 may be a circuit formed on the surface of the base 100 or an electrode attached to the surface of the base 100. The connection method between the electrical connector 200 and the base 100 may be determined depending on the materials of the base 100 and the mounting method of the light-emitting assembly. This is a conventional technique and will not be described here. Each light-emitting assembly is electrically connected to an external power source via the electrical connection member 200. The light-emitting module includes at least three light-emitting units 300. Specifically, in this embodiment, three, four or more light emitting units 300 can be installed in the same light emitting assembly, and the different light emitting units 300 may generally have a fixed interval or no interval, which can be specifically determined according to the light emission effect. When the different light emitting units 300 are installed at intervals, the light emission efficiency of the light source is generally high, and in this case, the pitch between the different light emitting units 300 can be the same or different, which can be specifically set according to the light emission effect of the light source.

[0054] The light-emitting unit 300 includes a blue light chip 310 and a wavelength conversion element 320 formed on the light-emitting side of the blue light chip 310. At least two blue light chips 310 in the same light-emitting assembly have peak wavelengths that differ by 3 nm or more. In this embodiment, one or more blue light chips 310 may be installed in the same light-emitting unit 300. When two or more blue light chips 310 are installed in a single blue light chip 310, the blue light chips 310 typically have the same or slightly different peak wavelengths. The light emitted by all the light-emitting units 300 in the same light-emitting assembly can be mixed to form near-natural light with a wavelength of 400-700 nm, and the absolute spectral power of the near-natural light in the 640-700 nm wavelength band is greater than 0.7.

[0055] For ease of explanation, in some of the following content, the "natural light-like LED light source" will be simply referred to as the light source or the present light source, and those skilled in the art should understand that the "light source," "the present light source," and "natural light-like LED light source" hereinafter generally refer to the "natural light-like LED light source" in this embodiment.

[0056] Regarding the wavelength range of each color light in visible light, red light wavelength is 622-700nm, orange light wavelength is 597-622nm, yellow light wavelength is 577-597nm, green light wavelength is 492-577nm, cyan light wavelength is 475-492nm, blue light wavelength is 435-475nm, and violet light wavelength is 380-435nm. In this embodiment, the wavelength band of 640-700nm corresponds to red light, which can penetrate 10mm deep under the skin, promote blood circulation in the eye, and have the effect of preventing eye fatigue.

[0057] In the field of LED lighting, research into lighting sources that are close to natural light is one of the development trends in this field, and is the direction that many researchers and units are constantly striving for. In the prior art, there have been several lighting products that have been designed to resemble natural light. Generally, the light emitted by such products is called "near-natural light." Near-natural light refers to a spectral shape (relative spectral power of corresponding wavelength bands) that is close to natural light, and at least some optical parameters that are close to natural light, although this degree of closeness is not limited to a certain numerical value. The near-natural light LED light source in this embodiment can also achieve a lighting effect that is closer to natural light, and can also improve the absolute spectral power of red light.

[0058] Specifically, the basic support structure of this light source is a base 100, and the light emitting assemblies are mounted on the base 100. The number of light emitting assemblies may be one, two, or more, with the structures and functions of each light emitting assembly being identical. In this embodiment, one set is preferred. Each set of light emitting assemblies includes at least three light emitting units 300. That is, the light source emits near-natural light by mixing the light emitted by the at least three light emitting units 300. Referring to FIG. 15 , the light emitting unit 300 includes a blue light chip 310 and a wavelength conversion element 320 formed on the light-emitting side of the blue light chip 310. The blue light chip 310 emits blue light, and the wavelength conversion element 320 wavelength-converts the monochromatic light emitted by the blue light chip 310 to generate other colored light (which may be white light or other colored light), and the multiple colored lights are mixed to form the near-natural light. Specifically, in this embodiment, each light emitting unit 300 may emit light having a full-color bionic spectrum or a partial spectrum, and the light emitted by all the light emitting units 300 located in the same light emitting assembly can be mixed to form near-natural light with a wavelength of 400-700 nm, and the absolute spectral power of the near-natural light in the wavelength band of 640-700 nm should be greater than 0.7. Furthermore, since each set of light emitting assemblies can emit near-natural light, when the light source includes multiple sets of light emitting assemblies, they can all emit near-natural light in the same way.

[0059] For ease of understanding, FIG. 3 shows the spectrum of near-natural light that can be achieved by the light source of this embodiment (e.g., (a) in FIG. 3) and the spectrum of light formed by a general light source (e.g., (b) in FIG. 3). As can be seen from this figure, the spectrum of near-natural light that can be achieved by the light source of this embodiment is complete, and the absolute spectral power of the wavelength band of 640-700 nm in the near-natural light in the spectrum is greater than 0.7. That is, the red light in the 640-700 nm range is saturated. In this way, the ciliary muscle is not constantly pulled forward, the eye axis is shortened, and the health level of lighting that is close to natural light is improved. Furthermore, as can be seen from the above spectrum, the proportion of blue light in the spectrum of near-natural light that can be achieved by the light source of this embodiment is reduced. This is beneficial for protecting eyesight, especially the eyesight of infants and children, and is also beneficial for reducing health problems caused by excessive blue light.

[0060] At the same time, the peak wavelengths of at least two blue light chips 310 located in the same light-emitting assembly differ by 3 nm or more, which can effectively improve the absolute spectral power of blue light compared to using blue light chips 310 with the same peak wavelength, solve the problem of low blue light that has long existed in near-natural light research, make quasi-natural light closer to real natural light, and further improve the color rendering index.

[0061] The light source according to the embodiment of the present application has at least the following effects.

[0062] First, each light-emitting assembly in this light source combines at least three light-emitting units 300 to obtain a full-color bionic spectrum closer to natural light. Compared with traditional white light illumination, the wavelengths of near-natural light are more complete, and the absolute spectral power of each wavelength band is closer to natural light, resulting in a more comfortable visual sensation.

[0063] Secondly, the absolute spectral power of red light is improved, and red light in the 640-700nm range in particular has the effect of promoting blood circulation in the eyes and preventing eye fatigue. At the same time, red light in the 640-700nm range is saturated, and does not constantly pull the ciliary muscle forward, shortening the eye axis and improving the health level of lighting that is closer to natural light.

[0064] Third, it adopts a combination of at least three light-emitting units 300, which has a simple structure and good variable controllability during the debugging process, enabling debugging of near-natural light, and solving the problem that the combination of multiple light-emitting elements cannot produce near-natural light, and the problem that the combination of blue light chips and fluorescent adhesives cannot obtain near-natural light.

[0065] Fourth, the peak wavelengths of at least two blue light chips 310 located in the same light-emitting assembly differ by more than 3 nm, reducing the blue light while improving the absolute spectral power of the blue light, solving the problem of low blue light that has long existed in near-natural light research, making the near-natural light closer to real natural light, and further improving the color rendering index.

[0066] Fifth, the light emitting unit 300 can adopt a micro-light emitter that meets the performance requirements. The entire light source is a micro-lamp bead, and multiple lamp beads can be arranged in any form on the base of various lamp fixtures. Its volume is small, it can be installed at any position on the base, it is flexible in application, the light emission of the entire lamp is uniform, and the lighting effect is good.

[0067] Sixth, when combining multiple light-emitting units 300, each light-emitting unit 300 can be packaged with its own wavelength conversion element 320 to achieve continuous, wide-spectrum color light, which is suitable for physical therapy products and overcomes the technical bottleneck of single wavelength and narrow spectrum color light sources in the industry.

[0068] In the above embodiment, when there are at least two blue light chips with the same peak wavelength in the same light emitting assembly, the absolute spectral power of the blue light in the spectrum formed by the LED light source close to natural light is small. To compensate for this drawback, in one preferred embodiment, the peak wavelengths of all the blue light chips located in the same light emitting assembly are different, and the peak wavelength interval between any two blue light chips is 3 nm or more.

[0069] By adopting this structure, measurements show that the spectrum formed by the LED light source that is close to natural light is closer to the spectrum of natural light, which solves the problem of the small absolute spectral power of blue light in the spectrum formed by the LED light source that is close to natural light.

[0070] In one preferred embodiment, each light-emitting unit can emit near-natural light with a wavelength of 400-700 nm. In this embodiment, different light-emitting units located in the same light-emitting assembly can all emit full-color bionic spectrum light, but the spectra corresponding to each light-emitting unit are generally different. As shown in FIG. 4, when three light-emitting units are provided in a light-emitting assembly, the spectrum corresponding to one light-emitting unit can be as shown in FIG. 4(a), the spectrum corresponding to another light-emitting unit can be as shown in FIG. 4(b), and the spectrum corresponding to the last light-emitting unit 300 can be as shown in FIG. 4(c). Of course, in other embodiments, the light-emitting units can generate spectra of other shapes, and this is not intended to be limiting. By adopting a structure in which each light-emitting unit can emit a full-color bionic spectrum, it is easier for the full-color bionic spectrum emitted by the entire light-emitting assembly to be close to natural light.

[0071] In addition, in this embodiment, each light emitting unit has a wavelength conversion element, which makes it easier to stabilize the spectrum of each light emitting unit and does not change with changes in driving current, compared to the conventional process in which multiple light emitting units share a single wavelength conversion element. As shown in Figure 5, tests have shown that the light source of this embodiment has small spectral aberrations at three different driving currents (100mA, 200mA, and 300mA) and has high spectral stability.

[0072] The wavelength conversion element can take various forms, including a fluorescent powder color wheel, a nonlinear optical crystal, or a phosphor, as an optical energy conversion element. Among these, when the wavelength conversion element includes a phosphor, the structure is simple and the size of the light source can be easily controlled. Specifically, the phosphor can be a fluorescent thin film, fluorescent ceramic, fluorescent glass, or the like. For ease of processing, fluorescent thin film, fluorescent coating, fluorescent colloid, or the like is preferred. These fluorescent structures are generally manufactured by mixing fluorescent powder with a binder such as silica gel or epoxy resin. Specifically, when the blue light chip is mounted on the base face-up, the phosphor can be a block structure formed after filling the entire reflective cup, or a fluorescent layer coated on the top of the reflective cup. Other forms can be specifically determined according to actual usage needs. When the blue light chip is mounted on the base flip-up, the phosphor can be a fluorescent thin film, fluorescent coating, or the like. More specifically, when the blue light chips are manufactured using the flip method, all the blue light chips are arranged in sequence at intervals, and fluorescent layers are manufactured on all the blue light chips at once using methods such as spraying or printing, and then each light emitting unit is manufactured using a dicing method.Finally, each light emitting unit is assembled on a base and electrically connected to the electrical connection members formed on the base.

[0073] The above phosphors can be installed in various ways, and for ease of understanding, an example will be given below.

[0074] In some embodiments, the phosphor is mixed with a phosphor composition, which includes a first phosphor powder, a second phosphor powder, and a third phosphor powder, wherein the first phosphor has an emission wavelength of 480-500nm, the second phosphor has an emission wavelength greater than 500nm and less than 620nm, and the third phosphor has an emission wavelength greater than 620nm, and the mass ratio of the first phosphor powder, the second phosphor powder, and the third phosphor powder is (15-70):(15-70):(13-70).

[0075] The fluorescent composition of the present embodiment is excited to generate full-color white light by blending the first, second and third fluorescent powders, which have different emission wavelengths and whose emission wavelengths are distributed within the visible light wavelength band. At the same time, by adjusting the mass ratio of the first, second and third fluorescent powders to (15-70):(15-70):(13-70), the white light has a low absolute optical power value of blue light and a high absolute optical power value of blue light, which can simulate natural light to a high degree and improve the color rendering index of the white light.

[0076] It can be understood that the emission wavelength of the phosphor refers to the wavelength corresponding to the peak value of the main peak of the spectrum generated when the phosphor is excited by photons.

[0077] In some embodiments, the first phosphor comprises phosphor A, which has an emission wavelength of 488-492 nm. The second phosphor comprises phosphor B, which has an emission wavelength of 523-542 nm. The third phosphor comprises phosphor C, phosphor D, phosphor E, and phosphor F. The emission wavelength of phosphor C is 628-681 nm, the emission wavelength of phosphor D is 718-722 nm, the emission wavelength of phosphor E is 738-742 nm, and the emission wavelength of phosphor F is 793-797 nm.

[0078] The fluorescent composition of the present invention includes phosphors A, B, C, E and F, each having an emission wavelength distributed throughout the visible light wavelength range, and the white light generated by the fluorescent composition of the present invention includes the visible light of all wavelengths within the range of 400-800 nm, and the white light further simulates natural light.

[0079] In another embodiment, phosphor B comprises phosphor B1 and phosphor B2, where phosphor B1 has an emission wavelength of 523-527nm and phosphor B2 has an emission wavelength of 538-542nm. Phosphor C comprises phosphor C1, phosphor C2 and phosphor C3, where phosphor C1 has an emission wavelength of 628-632nm, phosphor C2 has an emission wavelength of 658-662nm and phosphor C3 has an emission wavelength of 677-681nm.

[0080] In the illustrated example, phosphor A includes A1 and A2, where phosphor A1 has an emission wavelength of 480nm, phosphor A2 has an emission wavelength of 490nm, phosphor B1 has an emission wavelength of 525nm, phosphor B2 has an emission wavelength of 540nm, phosphor C1 has an emission wavelength of 630nm, phosphor C2 has an emission wavelength of 660nm, phosphor C3 has an emission wavelength of 679nm, phosphor D has an emission wavelength of 720nm, phosphor E has an emission wavelength of 740nm, and phosphor F has an emission wavelength of 795nm.

[0081] The first fluorescent powder, the second fluorescent powder and the third fluorescent powder can be separated or mixed with each other. By making the first fluorescent powder, the second fluorescent powder and the third fluorescent powder contain fluorescent powder components with different emission wavelengths, in the embodiments of the present application, the fluorescent powders with different wavelengths in the bionic fluorescent composition can be flexibly adjusted as needed. For example, in some embodiments, the mass ratio between the first fluorescent powder, the second fluorescent powder and the third fluorescent powder can be controlled to be (15-70):(15-70):(13-60), even (25-60):(25-55):(13-60), or even (31-40):(31-40):(13-60), and the fluorescent The mass ratio of fluorescent powder B1 to fluorescent powder B2 can be controlled as (20-85):(10-85), further as (30-75):(20-75), or further as (35-70):(25-70). The mass ratio of fluorescent powder C1, fluorescent powder C2, fluorescent powder C3, fluorescent powder D, fluorescent powder E and fluorescent powder F in the third fluorescent powder can be controlled as (3-35):(1-45):(3-60):(7-90):(7-60):(1-70), further as (7-30):(3-40):(3-50):(10-90):(10-60):(1-60), or further as (7-20):(3-30):(3-40):(20-80):(20-50):(1-50).

[0082] By controlling the mass ratio among the first fluorescent powder, the second fluorescent powder and the third fluorescent powder within the range defined by the mass ratio of the components in the second fluorescent powder and the third fluorescent powder, the absolute optical power values ​​of different wavelength bands of the white light generated by the fluorescent composition of the present application can be adjusted, and the spectrum of the generated white light can be optimized, for example, the optical power of red light in the wavelength range of 640-700nm of the white light can be increased, making it closer to natural light, thereby improving the comfort and authenticity of the white light reflected on the environment and objects when used for lighting, and reducing the damage to the human body.

[0083] In some embodiments, the phosphor C in the third phosphor layer, the first phosphor, and the second phosphor form a first mixture, and the phosphor D, E, and F in the third phosphor layer form a second mixture, which are provided separately from the first mixture and the second mixture.

[0084] In another embodiment, the emission wavelength of phosphor A in the first mixture may be 490nm (A2), phosphor B may contain phosphor B3, which may have an emission wavelength of 532-537nm, specifically 535nm, phosphor C may contain the above phosphor C2, which may have an emission wavelength of 658-662nm, specifically 660nm, phosphor D in the second mixture may have an emission wavelength of 720nm, phosphor E may have an emission wavelength of 740nm, and phosphor F may have an emission wavelength of 795nm.

[0085] By dividing the phosphor composition into a first mixture and a second mixture, which are separately provided, the first mixture and the second mixture contain components with different emission wavelengths, and during film formation, the first mixture and the second mixture can be formed separately, allowing for flexible adjustment of the mass ratio of the first mixture and the second mixture, and further allowing for adjustment of the spectrum of white light emitted by the phosphor composition, optimizing the spectral distribution of the generated white light and making the white light closer to natural light.

[0086] In some embodiments, the mass ratio of phosphor A, phosphor B, and phosphor C in the first mixture can be controlled to be (10-80):(15-85):(1-40), or even (10-70):(15-85):(1-35), or even (15-60):(20-75):(1-30). The mass ratio of phosphor D, phosphor E, and phosphor F in the second mixture can be controlled to be (20-120):(10-90):(1-100), or even (30-100):(15-70):(1-80), or even (40-90):(20-60):(1-70).

[0087] The spectrum of the generated white light can be adjusted by controlling the mass ratio of the first mixture to the second mixture and the mass ratio of each component in the first mixture to the second mixture. By controlling the mass ratio of the first mixture to the second mixture and the mass ratio of each component in the first mixture to the second mixture within this range, the spectrum of the generated white light can be optimized. For example, by increasing the mass ratio of the second mixture, the optical power of the red light in the wavelength range of 640-700 nm of the white light can be increased, making it closer to natural light.

[0088] In some embodiments, the phosphor A, phosphor B, phosphor C, phosphor D, phosphor E and phosphor F are selected from nitrides, Y3Al 12 For example, the fluorescent powder A may be gallium-doped yttrium aluminum garnet, specifically, yttrium trialuminum gallium pentaoxygen dodecyl [Y(Al,Ga)O]. 12 ], and phosphor B may be BaSi2O2N2 (barium strontium dioxygen dinitrogen dinitride, 1222), and phosphor C, phosphor D, phosphor E and phosphor F may be (Ca, Sr)AlSiN3 (calcium strontium aluminum silicon nitride trinitride, 1113) or fluoride, specifically, for example, K2SiF6:Mn 4+ (potassium hexafluorosilicate). Fluorescent powders A, B, C, D, E and F of each emission wavelength can be directly purchased commercially according to their emission wavelength.

[0089] It should be noted that any of the phosphors A, B, C, D, E, and F may contain any number of compounds, and may be a pure product containing only a single compound or a mixture containing multiple compounds. For example, phosphor B may further contain phosphor B1 and phosphor B2, and phosphor C may further contain phosphor C1, phosphor C2, and phosphor C3. Of course, phosphor B1, phosphor B2, phosphor C1, phosphor C2, and phosphor C3 may be a pure product containing only a single compound or a mixture containing multiple compounds. For example, phosphor C1 may be (Ca, Sr)AlSiN3, or (Ca, Sr)AlSiN3 and K2SiF6:Mn 4+ It may also be a mixture containing

[0090] 6, in some embodiments, the phosphor includes a first fluorescent portion 321, a second fluorescent portion 322, and a third fluorescent portion 323 arranged in order along the light emission direction, where the first fluorescent portion 321 includes a first fluorescent powder, the second fluorescent portion 322 includes a second fluorescent powder, and the third fluorescent portion 323 includes a third fluorescent powder. Here, the first fluorescent powder, the second fluorescent powder, and the third fluorescent powder are the first fluorescent powder, the second fluorescent powder, and the third fluorescent powder in the above-mentioned embodiments of the present application, and for space reasons, the description thereof will be omitted here. The structure of each fluorescent portion in this embodiment can be determined according to specific circumstances. For example, when the blue light chip is mounted on the base in a face-up manner and the phosphor has a block structure filling the entire reflective cup, the first fluorescent part 321 may be a block structure in which it is spread out at the bottom of the reflective cup in a dispensing manner, the second fluorescent part 322 may be a block structure in which it is filled in the middle of the reflective cup in a dispensing manner on the upper surface of the first fluorescent part 321, and the third fluorescent part 323 may be a block structure in which it is filled at the top of the reflective cup in a dispensing manner on the upper surface of the second fluorescent part 322. When the phosphor has a thin film or layer structure, the first fluorescent part 321, the second fluorescent part 322, and the third fluorescent part 323 may be stacked fluorescent thin films or fluorescent coatings.

[0091] In this embodiment, each layer may contain one type of fluorescent powder, or multiple types of fluorescent powder. When multiple types of fluorescent powder are present, no chemical reactions occur between the different fluorescent powders, and the properties of each fluorescent powder remain unchanged. Only the types of light emitted through the layer increase with the number of fluorescent powder types. When the first fluorescent unit 321 contains one type of fluorescent powder, only that type of fluorescent powder is excited and emits light of the corresponding wavelength when the light emitted from the blue light chip 310 passes through the layer. When the first fluorescent unit 321 contains multiple types of fluorescent powder, each fluorescent powder is excited and emits light of the corresponding wavelength when the light emitted from the blue light chip 310 passes through the layer, resulting in the layer emitting multiple light of different wavelengths. The same principle applies to the other fluorescent units. The more types of fluorescent powder present in each fluorescent unit, the more types of light emitted, and ultimately, all the light mixes to form near-natural light.

[0092] The first fluorescent part 321, the second fluorescent part 322, and the third fluorescent part 323 contain the first fluorescent powder, the second fluorescent powder, and the third fluorescent powder, respectively, so that the ratio and concentration of the first fluorescent powder, the second fluorescent powder, and the third fluorescent powder can be flexibly adjusted during film formation, and the generated white light spectrum is closer to natural light. At the same time, compared to mixing three types of fluorescent powder in one layer, the use of the phosphor of this embodiment can reduce the light loss of the entire light source and increase the light efficiency.

[0093] In some embodiments, the concentration of the first fluorescent powder in the first fluorescent part can be controlled to be 30-85%, further 40-75%, or further 60-69%, where the concentration of the first fluorescent powder is the ratio of the first fluorescent powder to the total mass of the first fluorescent powder and the colloid.

[0094] The concentration of the second fluorescent powder in the second fluorescent part can be controlled to be 30-85%, further 45-75%, or further 60-69%, where the concentration of the second fluorescent powder is the ratio of the second fluorescent powder to the total mass of the second fluorescent powder and colloid.

[0095] Furthermore, the concentration of the third fluorescent powder in the third fluorescent part can be controlled to be 40%-87%, further 50%-80%, or further 60%-69%, where the concentration of the first fluorescent powder is the ratio of the third fluorescent powder to the total mass of the third fluorescent powder and colloid.

[0096] The concentration of the first, second and third fluorescent powders determines the color temperature of the generated white light. The higher the concentration, the lower the color temperature will be, provided that the compounding ratio of the fluorescent powders and the thickness of the fluorescent part are constant. The lower the concentration, the higher the color temperature will be.

[0097] In another embodiment, the phosphor includes a fourth fluorescent section and a fifth fluorescent section arranged in order along the light emitting direction, the fourth fluorescent section including the first mixture, and the fifth fluorescent section including the second mixture, where the first mixture and the second mixture are the first mixture and the second mixture in the above embodiment of the present application, and description thereof will be omitted here.

[0098] The structures of the fourth and fifth fluorescent units in this embodiment are the same as those of the first, second, and third fluorescent units, and can be determined according to specific circumstances. When the blue light chip is mounted on the base in a face-up manner and the phosphor has a block structure filling the entire reflective cup, the fourth fluorescent unit may have a block structure in which it is dispensed into the middle and lower parts of the reflective cup, and the fifth fluorescent unit may have a block structure in which it is dispensed onto the top surface of the fourth fluorescent unit and filled into the middle and upper parts of the reflective cup. When the phosphor has a thin film or layer structure, the fourth and fifth fluorescent units may be laminated fluorescent thin films or fluorescent coatings.

[0099] In conventional white light sources, it is difficult to improve the optical power of red light with wavelengths above 640 nm. The second mixture primarily generates red light, and the proportion of the second mixture can be flexibly adjusted based on the fourth and fifth fluorescent parts, thereby improving the optical power of red light with wavelengths above 640 nm in the white light generated by the full-color bionic fluorescent film of the present embodiment and improving the similarity of the white light to natural light. Compared to mixing two types of fluorescent powder in a single layer, the use of the phosphor of the present embodiment reduces the overall light loss of the light source and improves the optical efficiency, but the optical efficiency of the phosphor of the present embodiment is lower than that of the phosphor of the first embodiment.

[0100] In some embodiments, the concentration of the first mixture in the fourth fluorescent section can be controlled to 40-85%, further 40-80%, or even 40-75%, where the concentration of the first mixture is the ratio of the first mixture to the total mass of the first mixture and the colloid.The concentration of the second mixture in the fifth fluorescent section can be controlled to 15-85%, further 20-80%, or even 30-75%, where the concentration of the second mixture is the ratio of the second mixture to the total mass of the second mixture and the colloid.

[0101] By controlling the concentrations of the first mixture and the second mixture within this range, the spectrum of different wavelength bands in the generated white light can be made closer to natural light.

[0102] In order to enable those skilled in the art to clearly understand the details and operations of the above embodiments of the present application, and to prominently embody the advanced performance of the LED light source that is close to natural light in the above embodiments, the above technical solutions are exemplarily described in the following several embodiments.

[0103] Examples 1 to 4

[0104] The phosphor comprises a first fluorescent part, a second fluorescent part, and a third fluorescent part stacked in order. The first fluorescent part comprises a first fluorescent powder and a colloid, the second fluorescent part comprises a second fluorescent powder and a colloid, and the third fluorescent part comprises a third fluorescent powder and a colloid. The colloid is silica gel. The mass ratio of the first fluorescent powder, the second fluorescent powder, and the third fluorescent powder is shown in Table 1 below. The phosphor is in the form of a fluorescent thin film.

[0105] The first fluorescent powder includes fluorescent powder A2, which is Y3(Al,Ga)5O with an emission wavelength of 490nm. 12 is.

[0106] The second phosphor includes BaSi2O2N2 phosphor B1 with an emission wavelength of 525nm and BaSi2O2N2 phosphor B2 with an emission wavelength of 540nm. The mass ratio of phosphor B1 to phosphor B2 is shown in Table 1.

[0107] The third phosphors include phosphor C1, phosphor C2, phosphor C3, phosphor D, phosphor E, and phosphor F. Phosphor C1 is (Ca,Sr)AlSiN3 with an emission wavelength of 630nm, phosphor C2 is (Ca,Sr)AlSiN3 with an emission wavelength of 660nm, phosphor C3 is (Ca,Sr)AlSiN3 with an emission wavelength of 679nm, phosphor D is (Ca,Sr)AlSiN3 with an emission wavelength of 720nm, phosphor E is (Ca,Sr)AlSiN3 with an emission wavelength of 740nm, and phosphor F is (Ca,Sr)AlSiN3 with an emission wavelength of 795nm. The mass ratios of phosphors C1, C2, C3, phosphor D, phosphor E, and phosphor F are shown in Table 1 below.

[0108] [Table 1]

[0109] For the film formation method of each fluorescent part in Examples 1 to 4, the film thickness and first fluorescent powder concentration of the first fluorescent part, the film thickness and second fluorescent powder concentration of the second fluorescent part, and the film thickness and third fluorescent powder concentration of the third fluorescent part, see Table 3.

[0110] Examples 5 to 8

[0111] The phosphor includes a fourth fluorescent part containing a colloid and a first mixture, and a fifth fluorescent part containing a colloid and a second mixture. The colloid is silica gel. The first mixture contains phosphor powder A2, phosphor powder B3, and phosphor powder C2, the mass ratio of which is shown in Table 2. Here, phosphor powder B3 is BaSi2O2N2 with an emission wavelength of 535 nm, and phosphor powder A2 and phosphor powder C2 are the same as phosphor powder A2 and phosphor powder C2 in Example 1. The phosphor is in the form of a fluorescent thin film.

[0112] The second mixture contains phosphor D, phosphor E and phosphor F, and the mass ratios thereof are shown in Table 2. Here, phosphor D, phosphor E and phosphor F are the same as phosphor D, phosphor E and phosphor F in Example A1.

[0113] [Table 2]

[0114] Table 3 shows the details of the film formation method for each phosphor portion in Examples 5 to 8, the film thickness and first mixture concentration of the fourth phosphor portion, and the film thickness and second mixture concentration of the fifth phosphor portion.

[0115] [Table 3]

[0116] As shown in Figures 7 to 14, the spectra of white light generated by the near-natural LED light sources according to Examples 1 to 8 of the present application are highly similar to those of natural light. The white light includes all visible light in the 400-700 nm wavelength band, and has a small absolute optical power value for violet light in the 380-435 nm wavelength band, a large absolute optical power value for blue light in the 475-492 nm wavelength band, and a large absolute optical power value for blue light in the 475-492 nm wavelength band. Because the optical power of all visible light in different wavelength bands is close to that of natural light, the white light highly simulates natural light, has a high color rendering index, is less harmful to the human body, and is comfortable for the human body.

[0117] In one preferred embodiment, the refractive index of each fluorescent section arranged along the light emission direction increases sequentially. That is, in the second embodiment of the phosphor, the refractive index of the first fluorescent section and the second fluorescent section increases sequentially. In the third embodiment of the phosphor, the refractive index of the first fluorescent section, the second fluorescent section and the third fluorescent section increase sequentially. This gradually increases the divergence angle of the light emitted by the blue light chip, and the radiation angle of the light emitted from each light-emitting unit is sufficiently large to meet the usage requirements.

[0118] 15, the phosphor generally comprises colloid 3211 and fluorescent powder 3212 mixed therein, and the thickness of the phosphor is generally more than twice the particle size of the fluorescent powder, i.e., the thickness of each fluorescent portion is generally more than twice the particle size of the fluorescent powder therein. Thus, in the phosphor, some fluorescent powders are often located in the propagation path of the light emitted by other fluorescent powders, and the light emitted by these excited fluorescent powders is blocked and reflected by other fluorescent powders during the emission process, causing it to deviate from the original emission path, thereby affecting the light output efficiency and luminous efficiency of the light source. To solve this problem, in one preferred embodiment, the thickness d1 of each fluorescent portion is greater than the particle size of any one of the fluorescent powders and less than 1.5 times the particle size of the largest fluorescent powder in the fluorescent portion. That is, as shown in FIG. 15, the thickness d1 of the first fluorescent portion 321 is larger than the particle diameter d2 of a single phosphor 3212 therein and smaller than 1.5 times the particle diameter d2 of the single phosphor; the thickness of the second fluorescent portion 322 is larger than the particle diameter of a single phosphor therein and smaller than 1.5 times the particle diameter of the single phosphor; and the thickness of the third fluorescent portion 323 is larger than the particle diameter of a single phosphor therein and smaller than 1.5 times the particle diameter of the single phosphor.

[0119] In addition, when different types of fluorescent powder are provided in a single fluorescent part, their particle sizes may be different. The phrase "larger than the particle size of any of the fluorescent powders" refers to a particle size larger than the particle size of the largest fluorescent powder in the fluorescent part. Similarly, the phrase "smaller than 1.5 times the particle size of the largest fluorescent powder in the fluorescent part" refers to a particle size smaller than 1.5 times the particle size of the largest fluorescent powder in the fluorescent part.

[0120] In this way, the thickness d1 of each fluorescent part is very thin, and all of the fluorescent powders therein can be dispersed and flattened in one layer, that is, no fluorescent powder is in the propagation path of the light emitted by other fluorescent powders. Furthermore, the light emitted by each fluorescent powder is smoothly emitted from the light-emitting surface of the phosphor and mixed with the light emitted by the blue light chip to form a predetermined spectrum. Furthermore, the spectrum of the light emitted by the light source is the predetermined spectrum and has high light efficiency.

[0121] In one preferred embodiment, the thickness d3 of the phosphor 320 is 0.3 mm or less, as shown in Figure 6. Conventional phosphors are generally thick, which is unfavorable for heat dissipation of the light source and increases the thickness of the light source. However, the phosphor has a limited thickness in this embodiment, which reduces the thickness of the light source and is favorable for heat dissipation of the blue light chip 310.

[0122] In one preferred embodiment, as shown in FIG. 18, the pitch d4 between two adjacent light-emitting units 300 is greater than the thickness of the phosphor, thereby reducing the risk that the light emitted by any one light-emitting unit 300 will be blocked by the adjacent light-emitting unit 300, thereby affecting the light output efficiency, and improving the light output efficiency of the light source.

[0123] Research has shown that, if the composition and concentration remain the same, the thicker the phosphor, the lower the color temperature. Based on this, if the color temperature does not meet the requirements, the thickness can be changed to adjust the color temperature, with little impact on other parameters. By adjusting the composition or thickness of the phosphor, the spectrum of the light emitted by the light source (400nm-700nm) can be made 95% similar to the natural spectrum of the same color temperature. Near-natural light has the following optical parameters:

[0124] When the color temperature of near-natural light is 2700K-3000K, the absolute spectral power in the 380-435nm wavelength band is less than 0.35, the absolute spectral power in the 435-475nm wavelength band is greater than 0.40, the absolute spectral power in the 475-492nm wavelength band is greater than 0.45, the absolute spectral power in the 492-577nm wavelength band is greater than 0.50, the absolute spectral power in the 577-597nm wavelength band is greater than 0.75, the absolute spectral power in the 597-622nm wavelength band is greater than 0.80, and the absolute spectral power in the 622-700nm wavelength band is greater than 0.80. When the color temperature of near-natural light is 4000K-4200K, the absolute spectral power in the 380-435nm wavelength band is less than 0.40, the absolute spectral power in the 435-475nm wavelength band is less than 0.65, the absolute spectral power in the 475-492nm wavelength band is greater than 0.60, the absolute spectral power in the 492-577nm wavelength band is greater than 0.65, the absolute spectral power in the 577-597nm wavelength band is greater than 0.80, the absolute spectral power in the 597-622nm wavelength band is greater than 0.8, and the absolute spectral power in the 622-700nm wavelength band is greater than 0.80. When the color temperature of near-natural light is 5500K-6000K, the absolute spectral power in the 380-435nm wavelength band is less than 0.45, the absolute spectral power in the 435-475nm wavelength band is less than 0.80, the absolute spectral power in the 475-492nm wavelength band is greater than 0.70, the absolute spectral power in the 492-577nm wavelength band is greater than 0.80, the absolute spectral power in the 577-597nm wavelength band is greater than 0.80, the absolute spectral power in the 597-622nm wavelength band is greater than 0.80, and the absolute spectral power in the 622-700nm wavelength band is greater than 0.70. When the color temperature of near-natural light is less than 4000K, the absolute spectral power in the 380-435nm wavelength band is less than 0.40, the absolute spectral power in the 435-475nm wavelength band is less than 0.65, the absolute spectral power in the 475-492nm wavelength band is greater than 0.30, the absolute spectral power in the 492-577nm wavelength band is less than 0.7, the absolute spectral power in the 577-597nm wavelength band is less than 0.80, the absolute spectral power in the 597-622nm wavelength band is greater than 0.8, and the absolute spectral power in the 622-700nm wavelength band is greater than 0.80.

[0125] In each of the above embodiments, each light emitting unit may have one blue light chip or two or more blue light chips, and the number of blue light chips in each light emitting unit may be the same or different. The peak wavelength of each blue light chip is 440-475nm, preferably 440-460nm.

[0126] When multiple blue light chips are included in the same light emitting unit, the peak wavelengths of all the blue light chips in the same light emitting unit must be the same, or the difference in peak wavelength between any two blue light chips must be within a predetermined range, where the predetermined range can be set based on the voltage difference of 0.1 V or less required for different blue light chips to generate light of the same peak wavelength.

[0127] According to this structure, different blue chips in the same light emitting unit use the same wavelength conversion element, which can ensure that the light output effects of different regions of a single light emitting unit are consistent, and facilitate the spectral design and processing of a single light emitting unit.Furthermore, compared with the case where each light emitting unit has one blue chip, when a single light emitting unit has multiple blue chips, i.e., when a single blue chip contains multiple blue chips, the short wavelength band of the spectrum formed by the entire light source can be made smoother.

[0128] In one preferred embodiment, the length of the single wavelength converting element is 4.0 mm or less, and the width is 3.0 mm or less. The single light emitting unit adopts this size, which is small in size and can reduce the volume of the entire light source.

[0129] 16-19, the blue chip 310 is preferably flip-mounted on the surface of the base 100, which is advantageous for efficient connection between the blue chip 310 and the electrical connection member 200 of the base 100 and for efficient heat dissipation. The blue chip 310 can be batch-formed by equipment, ensuring good consistency of the phosphor film between different products and avoiding the problem of poor consistency caused by the face-up chip dispensing process. Different products with the same color temperature are located at the same BIN position, ensuring good color temperature consistency and low cost. Furthermore, the flip-chip method further reduces the volume of the light emitting unit 300 and is advantageous for controlling the light source size.

[0130] Of course, the present application is not limited to the use of a flip chip, and a face-up chip may also be used, that is, the blue light chip 310 may be mounted face-up on the surface of the base 100. When the blue light chip 310 is mounted face-up on the surface of the base 100, the operation is simple and the structure is stable.

[0131] 16 and 17, in a preferred embodiment, the wavelength conversion element 320 is a fluorescent film, which is sprayed onto the light-emitting surface of the blue light chip 310. This structure reduces the thickness of the wavelength conversion element 320 and the volume of the light-emitting unit 300, which is advantageous for controlling the size of the light source.

[0132] In one preferred embodiment, as shown in Figures 18 and 19, the blue light chip 310 is mounted on the base 100 using a CSP packaging process. CSP (Chip Scale Package) packaging is the latest generation of memory chip packaging technology, and uses a die bonder and reflow process to directly bond the blue light chip 310 to the base 100. This structure allows the package volume of the light emitting unit 300 to be the same as the volume of the internal blue light chip 310, or the package volume exceeds the chip volume by no more than 20%. Because materials and processes such as reflective cups, brackets, and gold wires are omitted, the material and process are significantly reduced, and the LED is also called a package-free LED. At the same time, this structure allows each light-emitting unit 300 to flexibly combine any different spectra, such as color light sources with spectral widths of 600nm-700nm, 500nm-600nm, etc. In addition, it is possible to emphasize certain wavelengths in the single white light with a continuous spectrum of 400nm-700nm, such as a high-power 650nm single wavelength spectrum, or a high-power 650nm-660nm spectrum, or a high-power 500nm-700nm spectrum, etc., which can be used specifically for physical therapy or special effects products, breaking through the narrow spectrum limitations of LED physical therapy color light sources.

[0133] Specifically, when the blue light chip 310 is mounted on the base 100 using a CSP packaging process and the wavelength conversion element 320 uses a fluorescent film, there are three main packaging methods. The first, as shown in Figure 20, involves covering the top and four side surfaces of the flip-type blue light chip 310 with a fluorescent film to form a five-sided CSP structure. This structure has high light efficiency but poor color temperature consistency control between the top and the surroundings. The second, as shown in Figure 21, involves first coating a protective layer 330 on the side surfaces of the blue light chip 310 and then coating a fluorescent film on the top, leaving only one light-emitting surface at the top. This has good light consistency and directionality but results in a loss of light output from the surroundings and low light efficiency. The third, as shown in Figure 22, involves coating a layer of ultra-thin fluorescent film on the flip-type blue light chip 310 and then adding a transparent packaging layer 340 to form a fixed mold. This also has five-sided light emission, has high light efficiency and good light color uniformity, but requires a complex process. The first packaging method is preferred.

[0134] In one preferred embodiment, as shown in Figures 1 and 2, a reflector cup 400 is provided on the base 100, the light emitting unit 300 is provided in the reflector cup 400, and the electrical connection member 200 is formed on the surface of the base 100 and connected to the blue light chip 310 at the bottom of the reflector cup 400.

[0135] Specifically, in this embodiment, the inner wall of the reflecting cup 400 is provided with a light-reflecting surface for reflecting blue light, and the packaging colloid is used to protect the internal structure of the reflecting cup 400, stabilize the structure of the light-emitting unit 300, and adjust the refraction of light rays. The light emitted from the light-emitting unit 300 is thoroughly mixed and then output through the packaging colloid. The electrical connection member 200 is formed on the surface of the base 100, and positive and negative pins for connecting to a power source are formed outside the reflecting cup 400. A portion of the electrical connection member 200 is exposed from the bottom of the reflecting cup 400 and used to connect to the light-emitting unit 300. This configuration improves the light efficiency of the light source. In this embodiment, the wavelength conversion element may be formed inside the reflecting cup by a dispensing method or outside the reflecting cup, which can be flexibly selected according to design needs.

[0136] In the above embodiments, the phosphor may be directly coated on the surface of the blue light chip 310. However, in this case, approximately 60% of the blue light emitted by the blue light chip 310 is backscattered by the phosphor powder and then absorbed by the blue light chip 310, reducing the blue light radiation efficiency, i.e., the light-emitting efficiency of the blue light chip 310. As a result, the operation time of the blue light chip 310 increases, its temperature rises, and the phosphor tightly adheres to the periphery of the blue light chip 310, which causes the fluorescent material in the phosphor to easily age due to heat and increase light attenuation. Therefore, in some embodiments, as shown in FIG. 2 , a first packaging layer 500 is disposed between the blue light chip 310 and the wavelength conversion element 320 in each light-emitting unit 300. Specifically, the first packaging layer 500 covers the light-emitting surface of the blue light chip 310, and the phosphor is formed on the light-emitting surface of the first packaging layer 500. In this embodiment, the first packaging layer 500 may be made of a translucent material such as silica gel or resin, as long as it does not affect light propagation. The first package layer 500 can avoid direct contact between the phosphor and the blue light chip 310, and effectively solve the problems of light attenuation, heat dissipation and aging of the phosphor material.

[0137] In another embodiment, as shown in FIG. 23 , a first packaging layer 500 is disposed between the blue light chip 310 and the wavelength conversion element 320 in each light emitting unit 300, and the light-emitting surface of the wavelength conversion element 320 is covered with a second packaging layer 600. Specifically, the first packaging layer 500 covers the light-emitting surface of the blue light chip 310, the phosphor is formed on the light-emitting surface of the first packaging layer 500, and the second packaging layer 600 is formed on the light-emitting surface of the phosphor. Here, the first packaging layer 500 and the second packaging layer 600 may be made of a translucent material such as silica gel or resin, and the materials may be the same or different, which can be flexibly selected according to application needs. The first packaging layer 500 prevents direct contact between the phosphor and the blue light chip 310, effectively solving the problems of light attenuation, heat dissipation, and aging of the phosphor. By providing the second package layer 600, the phosphor can be effectively protected, reducing the risk of the phosphor being worn out during use and the risk of the phosphor material experiencing problems such as light attenuation and aging due to excessively high external temperatures, thereby effectively improving the service life of the phosphor.

[0138] In one specific embodiment, the first packaging layer 500 and the second packaging layer 600 are both made of silica gel, the wavelength conversion element 320 is made of phosphor, the reflective cup 400 is mounted face-up on the base 100, the blue light chip 310 of the light emitting unit 300 is mounted on the bottom of the reflective cup 400 and electrically connected to the electrical connection member 200 on the base 100, the blue light chip 310 is covered with the first packaging layer 500, the first packaging layer 500 is covered with phosphor, and the phosphor is covered with the second packaging layer 600. Here, the top surface of the first packaging layer 500 is flush with the top surface of the reflective cup 400, and the phosphor and the second packaging layer 600 are located outside the reflective cup 400. Of course, in other embodiments, at least one of the phosphor and the second packaging layer 600 may be provided inside the reflective cup 400.

[0139] The light emitting assemblies in the above embodiments may be packaged in various ways. In some embodiments, as shown in Figures 1 and 16, the light emitting assembly includes three light emitting units 300 spaced apart and arranged in a triangular pattern. For example, the three light emitting units 300 in the same light emitting assembly may be packaged in a 3535, 5050, or other similar manner to form a triangular layout. In another embodiment, as shown in Figure 18, all the light emitting units 300 in the same light emitting assembly are arranged in a straight line. Specifically, a 5630 type packaging method may be used. Both of the above two methods can meet the light output requirements of the light source, and are simple in structure and easy to package.

[0140] In another embodiment of the present application, a lighting device including an LED light source that is close to natural light according to each of the above embodiments can be provided, and the same technical effect can be achieved, so a description thereof will be omitted here.

[0141] The above are merely preferred embodiments of the present application, and specifically describe only the technical principles of the present application. However, these descriptions are only for the purpose of describing the principles of the present application, and should not be construed as limiting the scope of protection of the present application in any manner. Based on the interpretation herein, any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present application, as well as other specific embodiments of the present application that can be conceived by those skilled in the art without requiring creative efforts, should all be included in the scope of protection of the present application.

Claims

1. An LED light source that is close to natural light, The light emitting device includes a base, at least one light emitting assembly provided on the base, and an electrical connection member electrically connected to the light emitting assembly, the light emitting assembly including at least three light emitting units, each of which includes a blue light chip and a wavelength conversion element formed on the light emitting side of the blue light chip, the peak wavelengths of at least two of the blue light chips located in the same light emitting assembly differ by 3 nm or more, the light emitted by all the light emitting units in the same light emitting assembly can be mixed to form near-natural light with a wavelength of 400-700 nm, and the absolute spectral power of the near-natural light in the wavelength band of 640-700 nm is greater than 0.

7. An LED light source that is close to natural light.

2. 2. The LED light source according to claim 1, wherein the peak wavelengths of all the blue light chips located in the same light-emitting assembly are different, and the peak wavelength interval between any two of the blue light chips is 3 nm or more.

3. 2. The LED light source according to claim 1, wherein each of said light emitting units emits near-natural light with a wavelength of 400-700 nm.

4. 2. The LED light source according to claim 1, wherein the wavelength conversion element includes a phosphor.

5. A fluorescent composition is mixed in the phosphor, and the fluorescent composition is a first fluorescent powder having an emission wavelength of 480-500 nm; a second fluorescent powder having an emission wavelength greater than 500 nm and less than 620 nm; a third fluorescent powder having an emission wavelength of 620 nm or more; 5. The natural light-like LED light source according to claim 4, wherein the mass ratio of the first fluorescent powder to the second fluorescent powder to the third fluorescent powder is (15-70):(15-70):(13-70).

6. The first fluorescent powder includes fluorescent powder A, and the fluorescent powder A has an emission wavelength of 488-492 nm; The second phosphor includes phosphor B, and the emission wavelength of the phosphor B is 523-542 nm; 6. The natural light-like LED light source according to claim 5, wherein the third phosphors include phosphor C, phosphor D, phosphor E and phosphor F, and the emission wavelength of the phosphor C is 628-681nm, the emission wavelength of the phosphor D is 718-722nm, the emission wavelength of the phosphor E is 738-742nm, and the emission wavelength of the phosphor F is 793-797nm.

7. The first fluorescent powder, the second fluorescent powder and the third fluorescent powder are provided separately; The second phosphor B comprises phosphor B1 and phosphor B2, and the phosphor B1 has an emission wavelength of 523-527nm, and the phosphor B2 has an emission wavelength of 538-542nm. The mass ratio of the phosphor B1 to the phosphor B2 is (20-85):(10-85).

7. The natural light-like LED light source of claim 6, wherein the phosphor C in the third phosphor comprises phosphor C1, phosphor C2 and phosphor C3, the phosphor C1 having an emission wavelength of 628-632nm, the phosphor C2 having an emission wavelength of 658-662nm and the phosphor C3 having an emission wavelength of 677-681nm, and the mass ratio of the phosphor C1, the phosphor C2, the phosphor C3, the phosphor D, the phosphor E and the phosphor F is (3-35):(1-45):(3-60):(7-90):(7-60):(1-70).

8. The fluorescent powder C in the third fluorescent powder, the first fluorescent powder, and the second fluorescent powder form a first mixture; The third phosphors D, E and F form a second mixture; In the first mixture, the mass ratio of the fluorescent powder A to the fluorescent powder B to the fluorescent powder C is (10-80):(15-85):(1-40); In the second mixture, the mass ratio of the fluorescent powder D to the fluorescent powder E to the fluorescent powder F is (20-120):(10-90):(1-100); The LED light source according to claim 6, wherein the first mixture and the second mixture are provided separately.

9. 6. The LED light source according to claim 5, wherein the phosphor includes a first fluorescent part, a second fluorescent part, and a third fluorescent part, which are arranged in order along a light emitting direction, the first fluorescent part including the first fluorescent powder, the second fluorescent part including the second fluorescent powder, and the third fluorescent part including the third fluorescent powder.

10. 9. The LED light source according to claim 8, wherein the phosphor includes a fourth fluorescent part and a fifth fluorescent part that are sequentially arranged along a light emitting direction, the fourth fluorescent part including the first mixture, and the fifth fluorescent part including the second mixture.

11. 11. The LED light source according to claim 9, wherein the refractive index of each of the fluorescent portions arranged along the light emitting direction increases sequentially.

12. 11. The natural light-like LED light source according to claim 9 or 10, wherein the thickness of each fluorescent part is greater than the particle size of any one of the fluorescent powders and is smaller than 1.5 times the particle size of the largest fluorescent powder in the fluorescent part.

13. 11. The LED light source according to claim 4, wherein the thickness of the phosphor is 0.3 mm or less.

14. 11. The LED light source according to claim 4, wherein the pitch between two adjacent light emitting units is greater than the thickness of the phosphor.

15. The near-natural light has the following optical parameters: When the color temperature of the near-natural light is 2700K-3000K, the absolute spectral power in the 380-435nm wavelength band is less than 0.35, the absolute spectral power in the 435-475nm wavelength band is greater than 0.40, the absolute spectral power in the 475-492nm wavelength band is greater than 0.45, the absolute spectral power in the 492-577nm wavelength band is greater than 0.50, the absolute spectral power in the 577-597nm wavelength band is greater than 0.75, the absolute spectral power in the 597-622nm wavelength band is greater than 0.80, and the absolute spectral power in the 622-700nm wavelength band is greater than 0.80; When the color temperature of the near-natural light is 4000K-4200K, the absolute spectral power in the 380-435nm wavelength band is less than 0.40, the absolute spectral power in the 435-475nm wavelength band is less than 0.65, the absolute spectral power in the 475-492nm wavelength band is greater than 0.60, the absolute spectral power in the 492-577nm wavelength band is greater than 0.65, the absolute spectral power in the 577-597nm wavelength band is greater than 0.80, the absolute spectral power in the 597-622nm wavelength band is greater than 0.8, and the absolute spectral power in the 622-700nm wavelength band is greater than 0.80; When the color temperature of the near-natural light is 5500K-6000K, the absolute spectral power in the 380-435nm wavelength band is less than 0.45, the absolute spectral power in the 435-475nm wavelength band is less than 0.80, the absolute spectral power in the 475-492nm wavelength band is greater than 0.70, the absolute spectral power in the 492-577nm wavelength band is greater than 0.80, the absolute spectral power in the 577-597nm wavelength band is greater than 0.80, the absolute spectral power in the 597-622nm wavelength band is greater than 0.80, and the absolute spectral power in the 622-700nm wavelength band is greater than 0.70; When the color temperature of the near-natural light is less than 4000K, the absolute spectral power in the 380-435nm wavelength band is less than 0.40, the absolute spectral power in the 435-475nm wavelength band is less than 0.65, the absolute spectral power in the 475-492nm wavelength band is greater than 0.30, the absolute spectral power in the 492-577nm wavelength band is less than 0.7, the absolute spectral power in the 577-597nm wavelength band is less than 0.80, the absolute spectral power in the 597-622nm wavelength band is greater than 0.8, and the absolute spectral power in the 622-700nm wavelength band is greater than 0.

80. The LED light source according to any one of claims 1 to 10, which emits light similar to natural light.

16. An LED light source close to natural light described in any one of claims 1 to 10, characterized in that the same light-emitting unit includes multiple blue light chips, and the peak wavelengths of all the blue light chips located in the same light-emitting unit are the same, or the difference in peak wavelengths of any two of the blue light chips is within a predetermined range.

17. The LED light source according to any one of claims 1 to 10, wherein the blue light chip is flip-mounted on the surface of the base.

18. 18. The LED light source according to claim 17, wherein the wavelength conversion element is a fluorescent film, and the fluorescent film is formed on the light-emitting surface of the blue light chip by spray coating.

19. The near-natural light LED light source of claim 17 , wherein the blue light chip is mounted on the base by a CSP packaging process.

20. The LED light source according to any one of claims 1 to 10, wherein the blue light chip is mounted face-up on the surface of the base layer.

21. 21. The natural light-like LED light source of claim 20, wherein the base is provided with reflecting cups that correspond one-to-one to the light-emitting units, each of the light-emitting units being provided with a corresponding reflecting cup, and the electrical connection member is formed on the surface of the base and connected to the blue light chip at the bottom of the reflecting cup.

22. a first package layer is filled between the blue light chip and the wavelength conversion element in each of the light emitting units; Alternatively, the LED light source according to claim 21, wherein a first package layer is filled between the blue light chip and the wavelength conversion element in each light emitting unit, and the light output surface of the wavelength conversion element is covered with a second package layer.

23. the light-emitting assembly includes three light-emitting units spaced apart in a triangular pattern; Alternatively, all the light emitting units located in the same light emitting assembly are arranged along a straight line.

24. A lighting device comprising an LED light source that is close to natural light according to any one of claims 1 to 23.

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