Method of hybrid production of sun-like white light by LEDs and LED lamp set

Abstract

The application relates to the field of LED health lighting, and discloses a method for LED mixed generation of sunlight-like white light and an LED lamp set. The method comprises the following steps: determining the color points of each LED lamp bead around a blackbody radiation line, independently packaging each LED lamp bead, and comprising LED chips with specific peak wavelengths and various fluorescent powders; determining l target sunlight-like white light color points on the blackbody radiation line, and calculating l groups of luminous flux parameters; selecting a group of luminous flux parameters from the l groups of luminous flux parameters according to a preset target, and using the group of luminous flux parameters to control the m LED lamp beads to form mixed light, i.e. sunlight-like white light. According to the combination of different intensities of various light sources, the application changes the single waveband excitation of fluorescent powder for emitting white light by the existing full-spectrum white light LED into multi-waveband LED chip mixed dimming, fills the gap of the spectrum of about 480 nm, has a higher color rendering index, and has a more continuous mixed spectrum, and can realize sunlight-like dimming along the blackbody radiation line.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of LED healthy lighting, in particular to a method for LED mixed generation of sun-like white light and an LED lamp set. BACKGROUND

[0002] As a new type of lighting source, white light LED has significant advantages over traditional fluorescent lamps and incandescent lamps, such as energy saving, environmental protection, fast response speed, long service life, etc. At present, the LED industry is developing rapidly, the luminous efficiency of LED is continuously improved, and the price is decreasing year by year, so white light LED is gradually replacing traditional lighting equipment and widely entering the market.

[0003] With the rapid popularization of white light LED in the lighting field, the market demand for its quality is also getting higher and higher, especially in the field of indoor lighting. At the beginning, the demand for white light LED only focused on its "high brightness", but now more attention is paid to light color performance, such as color rendering index, color temperature, etc., and even the pursuit of full-spectrum lighting similar to sunlight. In order to meet market demand, domestic and foreign packaging enterprises have accelerated the research and development of full-spectrum white light LED products.

[0004] At present, there are mainly two ways to achieve full-spectrum white light LED: multi-chip type and single-chip type. Multi-chip type LED uses three primary color principle to integrate multiple LED chips emitting red, green and blue light to obtain white light by proportional mixing. Although this technology can flexibly adjust the color and color temperature by controlling the current of each LED chip, and the color gamut is wider, but the overall color rendering index is not high; single-chip type full-spectrum white light LED is simpler and has lower cost, and the spectrum is more continuous, but the color temperature is not adjustable. Traditional LED realizes full-spectrum sun-like white light lighting mainly by using single lamp bead packaging LED chip and multi-color fluorescent powder, which has single color temperature and poor spectral continuity, especially in the blue light band around 480nm, the wavelength range overlaps with the excitation spectrum of long-wavelength fluorescent powder, resulting in absorption and concave; using double-color lamp beads to adjust the color, the color points of the adjusted color deviate from the curved blackbody radiation line, and the white light is not pure. Blue light chip technology has spectral missing in the blue-green light part, and its color performance is not ideal, while purple / near-ultraviolet chip technology has low color rendering index and high production cost, etc. Therefore, it is of great significance to seek new white light LED technology to overcome the problems existing in the current technology. SUMMARY

[0005] The purpose of the present application is to at least partially solve the above technical problems, and to provide a method for LED mixed generation of sun-like white light and an LED lamp set.

[0006] The first aspect of the present application provides a method for LED mixed generation of sun-like white light, the method comprising the following steps:

[0007] 1) selecting m color points in CIE1931 chromaticity diagram, m≥3, m∈Z, taking the m color points as vertices to form a dimming region, the dimming region including all or part of blackbody radiation lines in 2700K-6500K color temperature range;

[0008] 2) in 400nm-460nm waveband range, determining m peak wavelengths as peak wavelengths of m LED chips according to the selected m color points; in 460nm-700nm waveband range, selecting n peak wavelengths as peak wavelengths of n kinds of phosphor; m≤n≤5, n∈Z;

[0009] The determination of the m peak wavelengths and the n peak wavelengths both satisfies the following first rule:

[0010] In the formula, λ P1 , λ P2 are two adjacent peak wavelengths, |λ P2 -λ P1 | is the absolute value of the difference between the two adjacent peak wavelengths, Δλ1 and Δλ2 are the half wave widths of λ P1 , λ P2 ;

[0011] 3) independently packaging m LED lamp beads by selecting 0-n kinds of phosphor from the n kinds of phosphor for each LED chip in the m LED chips, the light emitted by the m LED lamp beads in the powered state corresponding to the m color points;

[0012] The selection of 0-n kinds of phosphor from the n kinds of phosphor for each LED chip needs to satisfy the following second rule:

[0013] The emission spectrum waveband of the LED chip is within the excitation spectrum waveband of the phosphor;

[0014] 4) determining l target sunlight-like white light color points on the blackbody radiation line in the dimming region, calculating the luminous flux of each LED lamp bead in the m LED lamp beads for each target sunlight-like white light color point respectively, and obtaining l groups of luminous flux parameters;

[0015] 5) selecting a group of luminous flux parameters from the l groups of luminous flux parameters according to a preset target, for controlling the m LED lamp beads to form mixed light, i.e. sunlight-like white light.

[0016] Further, the light flux of each LED lamp bead is calculated according to the m color points, the target sun-like white light color point and the preset target sun-like white light light flux, and the target sun-like white light color point is a color point on the blackbody radiation line in the dimming region.

[0017] Further, when m is 3, the coordinates of the three color points are A(x A ,y A ), B(x B ,y B ), and C(x C ,y C ), the coordinates of the target sun-like white light color point are W(x W ,y W ), and the light fluxes of the three LED lamp beads are calculated according to the following formula:

[0018]

[0019] wherein φ W is the preset target sun-like white light light flux; φ A , φ B , and φ C are the light fluxes of the three LED lamp beads.

[0020] Further, the n kinds of fluorescent powders include fluorescent powder with a peak wavelength range of 470nm-490nm, and the fluorescent powder with a peak wavelength range of 470nm-490nm is independently packaged after being combined with the LED chip with the smallest peak wavelength in the m LED chips.

[0021] In the second aspect, the application provides an LED lamp set for generating sun-like white light, which is characterized in that the LED lamp set comprises m LED lamp beads, m≥3, m∈Z; each LED lamp bead is independently packaged, each LED lamp bead comprises one LED chip and 0-n kinds of fluorescent powders, the color point of each LED lamp bead is selected from the surrounding area of the blackbody radiation line in the CIE1931 color coordinate diagram, the peak wavelength of the LED chip contained in each LED lamp bead is different; each LED lamp bead is used to emit light of the corresponding color point through the contained LED chip or excite the corresponding fluorescent powder to emit light of the corresponding color point through the contained LED chip at a set light flux, and then form mixed light; in the LED lamp bead, the emission spectrum band of the LED chip is within the excitation spectrum band of the fluorescent powder.

[0022] Further, the peak wavelength of the LED chip is between 400nm and 460nm, and the peak wavelength range of the phosphor is between 470nm and 505nm at the lowest and between 660nm and 690nm at the highest.

[0023] Further, the peak wavelength of the LED chip in the m LED lamp beads is separated by 10nm-20nm.

[0024] Further, the m LED lamp beads include a first LED lamp bead independently encapsulated, and the phosphor in the first LED lamp bead has a peak wavelength range of 470nm-490nm.

[0025] Further, the LED lamp group includes a first LED lamp bead, a second LED lamp bead and a third LED lamp bead.

[0026] The peak wavelength of the LED chip in the first LED lamp bead is 415nm-420nm, the phosphor is excited at a peak wavelength of 480nm-490nm, and the ratio of the peak intensity of the LED to the peak intensity of the phosphor is 1:1.5-1:4.

[0027] The peak wavelength of the LED chip in the second LED lamp bead is 430nm-435nm, the phosphor is excited at a peak wavelength of 520nm-540nm and 560nm-580nm, and the ratio of the peak intensity of the LED chip to the peak intensity of the phosphor is 1:1:1-1:3:3.

[0028] The peak wavelength of the LED chip in the third LED lamp bead is 445nm-455nm, the phosphor is excited at a peak wavelength of 560nm-580nm, 615nm-635nm and 660nm-690nm, and the ratio of the peak intensity of the LED to the peak intensity of the phosphor is 1:7:7:9-1:14:20:50.

[0029] Further, the color point of the first lamp bead is A (0.1668, 0.2703), the peak wavelength of the LED chip contained therein is 415nm, the phosphor with the peak wavelength of 483nm is excited, and the ratio of the peak intensity of the LED chip to the peak intensity of the phosphor is 1:1.6; the color point of the second lamp bead is B (0.4113, 0.4981), the peak wavelength of the LED chip contained therein is 430nm, the phosphor with the peak wavelength of 530nm and 574nm is excited, and the ratio of the peak intensity of the LED chip to the peak intensity of the phosphor is 1:0.65:1.3; the color point of the third lamp bead is C (0.5832, 0.3919), the peak wavelength of the LED chip contained therein is 460nm, the phosphor with the peak wavelength of 574nm, 627nm and 684nm is excited, and the ratio of the peak intensity of the LED chip to the peak intensity of the phosphor is 1:4:8:10.

[0030] Further, the LED lamp set comprises a first LED lamp bead, a second LED lamp bead, a third LED lamp bead and a fourth LED lamp bead; the color point of the first LED lamp bead is A (0.1673, 0.2726), the peak wavelength of the LED chip contained therein is 415nm, the phosphor with the peak wavelength of 483nm is excited, and the ratio of the peak intensity of the LED to the peak intensity of the phosphor is 1:2; the color point of the second LED lamp bead is B (0.1667, 0.0138), the peak wavelength of the LED chip contained therein is 430nm; the color point of the third LED lamp bead is C (0.4420, 0.5010), the peak wavelength of the LED chip contained therein is 445nm, the phosphor with the peak wavelength of 530nm and 574nm is excited, and the ratio of the peak intensity of the LED to the peak intensity of the phosphor is 1:2.4:3.2; the color point of the fourth LED lamp bead is D (0.6323, 0.3619), the peak wavelength of the LED chip contained therein is 460nm, the phosphor with the peak wavelength of 574nm, 627nm and 684nm is excited, and the ratio of the peak intensity of the LED to the peak intensity of the phosphor is 1:10:70:100.

[0031] Compared with the prior art, the present application has at least one of the following advantages or at least part of one advantage:

[0032] (1) The method for generating the sun-like white light provided by the application uses multi-peak wavelength LED chips and fluorescent powder to mix and adjust light, selects appropriate LED chips and fluorescent powder to cover the entire visible light band, splits them into multiple parts, each lamp bead uses different waveband LED chips to excite corresponding fluorescent powder to generate a combined light source, and adjusts the luminous flux of each LED lamp bead to mix and superimpose the spectrum, so that the sun-like white light with continuous spectrum and similar to the sun spectrum is obtained, the spectrum characteristics are similar to the sun spectrum, the short-wavelength blue light hazard is removed, the purple light does not protrude, and the blue and green do not sink.

[0033] (2) The technical solution provided by the application calculates different luminous flux parameter combinations from different color points on the black body radiation line in the light adjustment area, that is, different luminous flux parameters correspond to sun-like white light with different color temperatures, and by changing the luminous flux (selecting different luminous flux parameter combinations), the light adjustment and color adjustment along the black body radiation line are realized, and the problem of unadjustable color temperature of traditional single LED chip light adjustment is solved.

[0034] (3) The LED lamp group for generating sun-like white light provided by the application separately encapsulates 480nm fluorescent powder, which avoids the problem that the emission spectrum of 480nm fluorescent powder overlaps with the excitation spectrum of long-wavelength fluorescent powder, and the 480nm waveband spectrum is absorbed and sinks. BRIEF DESCRIPTION OF DRAWINGS

[0035] These and / or other aspects and advantages of the present application will become apparent and readily appreciated from the following description, taken in conjunction with the accompanying drawings, in which:

[0036] Figure 1 A triangle color adjustment area surrounded by three color points in CIE1931 in an embodiment of the application;

[0037] Figure 2 A quadrilateral color adjustment area surrounded by four color points in CIE1931 in an embodiment of the application;

[0038] Figure 3 A schematic diagram of a three-color LED lamp bead on a substrate provided by an embodiment of the application;

[0039] Figure 4 A packaging structure schematic diagram of an LED lamp bead provided by an embodiment of the application;

[0040] Figure 5 A low-color-temperature 2700K-3500K mixed sun-like white light spectrum comparison diagram of a three-color lamp bead provided by embodiment 1 of the application;

[0041] Figure 6 A high-color-temperature 4000K-6500K mixed sun-like white light spectrum comparison diagram of a three-color lamp bead provided by embodiment 2 of the application;

[0042] Figure 7 Four-color lamp bead 2700K-6500K mixed sun-like white light spectrum provided for embodiment 3 of the present application. DETAILED DESCRIPTION

[0043] The technical solutions of the present application will be further specifically explained below by embodiments and in conjunction with the drawings. In the description, the same or similar reference numerals indicate the same or similar components. The following description of the embodiments of the present application with reference to the drawings is intended to explain the general inventive concept of the present application, and should not be understood as a limitation of the present application.

[0044] One embodiment of the present application provides a method for LED mixed generation of sun-like white light, comprising the following steps:

[0045] S1. Selecting m color points in the CIE1931 color coordinate diagram, m≥3, m∈Z, taking the m color points as vertices to enclose a dimming region, and the dimming region includes all or part of the blackbody radiation line in the 2700K-6500K color temperature range.

[0046] In one embodiment of the present application, m is 3, and a triangular region with 3 color points as vertices is taken as the dimming region, as shown in Figure 1 .

[0047] In one embodiment of the present application, m is 4, and a quadrilateral region with 4 color points as vertices is taken as the dimming region, as shown in Figure 2 .

[0048] S2. In the 400nm-460nm waveband range, m peak wavelengths are determined as the peak wavelengths of m LED chips according to the selected m color points; in the 460nm-700nm waveband range, n peak wavelengths are selected as the peak wavelengths of n kinds of fluorescent powder; m≤n≤5, n∈Z;

[0049] Wherein, the determination of the m peak wavelengths and the n peak wavelengths both satisfy the following first rule:

[0050] In the formula, λ P1 , λ P2 are two adjacent peak wavelengths, |λ P2 -λ P1 | is the absolute value of the difference between the two adjacent peak wavelengths, Δλ1, Δλ2 are the half wave widths of λ P1 , λ P2 ;

[0051] The peak wavelength of the LED chip is in the range of 400-460 nm, and the peak wavelength of each of the m LED chips is separated by 10-20 nm. The peak wavelength of the phosphor is in the range of 460-700 nm, and is divided into n types, covering the entire visible light range of 400-700 nm.

[0052] In one embodiment of the present application, the n types of phosphor include a phosphor with a peak wavelength range of 470-490 nm, which is independently packaged in combination with the LED chip with the smallest peak wavelength among the m LED chips.

[0053] In one embodiment of the present application, when m is 3, the peak wavelength of the three LED chips is selected in the three wavelength ranges of 410-420 nm, 425-435 nm, and 440-460 nm.

[0054] In one embodiment of the present application, when m is 3, the peak wavelength of the three LED chips is selected in the three wavelength ranges of 415-420 nm, 430-435 nm, and 445-455 nm.

[0055] In one embodiment of the present application, n is 5, and the peak wavelength of the five types of phosphor is selected in the five wavelength ranges of 470-500 nm, 520-540 nm, 560-590 nm, 615-635 nm, and 660-690 nm.

[0056] S3. In the m LED chips, each LED chip is independently packaged after selecting 0-n types of phosphor from the n types of phosphor for emitting light of a corresponding color point.

[0057] When selecting the phosphor, not only the color point of the light needs to be considered, but also the emission spectrum band of the LED chip needs to be in the excitation spectrum band of the phosphor.

[0058] Specifically, the excitation spectrum band of the phosphor with a peak wavelength in the five wavelength ranges of 470-500 nm, 520-540 nm, 560-590 nm, 615-635 nm, and 660-690 nm is in the range of 380-420 nm, 380-450 nm, 380-450 nm, 380-480 nm, and 380-480 nm.

[0059] In one embodiment of the present application, the LED chip with a shorter peak wavelength excites the phosphor with a shorter peak wavelength, and the LED chip with a longer peak wavelength excites the phosphor with a longer peak wavelength.

[0060] In one embodiment of the present application, in the case of 3 LED lamp beads, the LED chip with peak wavelength 410nm-420nm excites the phosphor with peak wavelength 480nm-500nm, the LED chip with peak wavelength 425nm-435nm excites the phosphor with peak wavelength 520nm-580nm, and the LED chip with peak wavelength 440nm-460nm excites the phosphor with peak wavelength 570nm-690nm.

[0061] In one embodiment of the present application, in the case of 3 LED lamp beads, each LED lamp bead is packaged to excite corresponding phosphor with LED chip of different waveband to reach corresponding color point, the LED chip with peak wavelength 415nm-420nm excites the phosphor with peak wavelength 480nm-490nm, and the ratio of LED peak intensity to phosphor peak intensity is 1:1.5-1:4; the LED chip with peak wavelength 430nm-435nm excites the phosphor with peak wavelength 520nm-540nm, 560nm-580nm, and the ratio of LED peak intensity to phosphor peak intensity is 1:1:1-1:3:3; the LED chip with peak wavelength 445nm-455nm excites the phosphor with peak wavelength 560nm-580nm, 615nm-635nm, 660nm-690nm, and the ratio of LED peak intensity to phosphor peak intensity is 1:7:7:9-1:14:20:50.

[0062] In one embodiment of the present application, m is 3, and the 3 LED lamp beads are designed as follows:

[0063] The color point of the first LED lamp bead is A (0.1668, 0.2703), the LED chip contained therein has peak wavelength 415nm, excites the phosphor with peak wavelength 483nm, and the ratio of LED chip peak intensity to phosphor peak intensity is 1:1.6;

[0064] The color point of the second LED lamp bead is B (0.4113, 0.4981), the LED chip contained therein has peak wavelength 430nm, excites the phosphor with peak wavelength 530nm, 574nm, and the ratio of LED chip peak intensity to phosphor peak intensity is 1:0.65:1.3;

[0065] The color point of the third LED lamp bead is C (0.5832, 0.3919), the LED chip contained therein has peak wavelength 460nm, excites the phosphor with peak wavelength 574nm, 627nm, 684nm, and the ratio of LED chip peak intensity to phosphor peak intensity is 1:4:8:10.

[0066] In one embodiment of the present application, m is 4, and the 4 LED lamp beads are designed as follows:

[0067] The color point of the first LED lamp bead is A (0.1673, 0.2726), the peak wavelength of the LED chip contained in the first LED lamp bead is 415 nm, the phosphor with an excitation peak wavelength of 483 nm is excited, and the ratio of the peak intensity of the LED to the peak intensity of the phosphor is 1:2;

[0068] The color point of the second LED lamp bead is B (0.1667, 0.0138), the peak wavelength of the LED chip contained in the second LED lamp bead is 430 nm; at this time, the color point of the light emitted by the single LED chip meets the requirements of constituting the mixed color quadrilateral area, and the phosphor is not needed.

[0069] The color point of the third LED lamp bead is C (0.4420, 0.5010), the peak wavelength of the LED chip contained in the third LED lamp bead is 445 nm, the phosphor with peak wavelengths of 530 nm and 574 nm is excited, and the ratio of the peak intensity of the LED to the peak intensity of the phosphor is 1:2.4:3.2;

[0070] The color point of the fourth LED lamp bead is D (0.6323, 0.3619), the peak wavelength of the LED chip contained in the fourth LED lamp bead is 460 nm, the phosphor with peak wavelengths of 574 nm, 627 nm and 684 nm is excited, and the ratio of the peak intensity of the LED to the peak intensity of the phosphor is 1:10:70:100.

[0071] S3. Determine l target sunlight-like white light color points on the blackbody radiation line in the dimming region, and calculate the luminous flux of each LED lamp bead in the m LED lamp beads for each target sunlight-like white light color point to obtain l sets of luminous flux parameters.

[0072] In an embodiment of the present application, the calculation of the luminous flux of each LED lamp bead in the m LED lamp beads for a target sunlight-like white light color point is specifically: the luminous flux of the m LED lamp beads is calculated according to the m color points, the target sunlight-like white light color point and the preset target sunlight-like white light luminous flux.

[0073] When m is 3, the coordinates of the target sunlight-like white light color point are W (x W ,y W ), the coordinates of the three color points are A (x A ,y A ), B (x B ,y B ) and C (x C ,y C ), and a three-color dimming mathematical model shown in equation (1) is established:

[0074]

[0075] wherein, φW is the light flux of the preset target sun-like white light; φ A ,φ B ,φ C is the light flux of the three LED lamp beads.

[0076] Simplify to obtain the calculation formula of the light flux of the three LED lamp beads, as shown in formula (2):

[0077]

[0078] is the light flux of the preset target sun-like white light; φ W is the light flux of the preset target sun-like white light; φ A ,φ B ,φ C is the light flux of the three LED lamp beads.

[0079] S4. Select a group of light flux parameters from the l groups of light flux parameters according to the preset target, for controlling the m LED lamp beads to form mixed light, i.e. sun-like white light.

[0080] The embodiment of the present application calculates different light flux parameters from different color points selected on the blackbody radiation line in the dimming area, i.e. different light flux parameters correspond to sun-like white light of different color temperatures, and through the selection of different light flux parameters, the dimming and color adjustment along the blackbody radiation line are realized.

[0081] Embodiment 1

[0082] The embodiment of the present application provides an LED lamp group for generating sun-like white light, and the light emitting device comprises a support or substrate, three kinds of lamp beads and a control system.

[0083] As shown in formula (1), the embodiment of the present application provides a light emitting device, which comprises a support or substrate, three groups of three kinds of LED lamp beads and a control system. Figure 3 As shown in formula (1), the embodiment of the present application provides a light emitting device, which comprises a support or substrate, three groups of three kinds of LED lamp beads and a control system. Figure 4 As shown in formula (1), the embodiment of the present application provides a light emitting device, which comprises a support or substrate, three groups of three kinds of LED lamp beads and a control system.

[0084] The chip and the fluorescent powder combination selected in the embodiment are as follows:

[0085] The lamp bead A uses an LED chip with a peak wavelength of 415 nm, and excites a blue fluorescent powder with a peak wavelength of 483 nm and a half peak width of 86 nm.

[0086] The lamp bead B uses an LED chip with a peak wavelength of 430 nm to excite a green phosphor with a peak wavelength of 529 nm and a half peak width of 106 nm in the emission spectrum; a yellow phosphor with a peak wavelength of 574 nm and a half peak width of 129 nm in the emission spectrum;

[0087] The lamp bead C uses an LED chip with a peak wavelength of 460 nm to excite a yellow phosphor with a peak wavelength of 574 nm and a half peak width of 129 nm in the emission spectrum; a short-wavelength red phosphor with a peak wavelength of 627 nm and a half peak width of 76 nm in the emission spectrum; and a long-wavelength red phosphor with a peak wavelength of 684 nm and a half peak width of 92 nm in the emission spectrum.

[0088] Solder paste is applied on the bracket, and the LED chip is placed on the heating platform at 260 degrees Celsius to fix the chip. AB glue mixed with phosphor is used for covering. The powder-to-glue ratio of the lamp bead A is 1:4; the powder-to-glue ratio of the lamp bead B is 1:6; the green phosphor-to-yellow phosphor ratio is 2:3; the powder-to-glue ratio of the lamp bead C is 1:3; the yellow phosphor-to-short-wavelength red phosphor ratio and the long-wavelength red phosphor ratio is 8:2:3; a far-field integrating sphere is used for testing, and after passing the test, the lamp bead is baked at 80 degrees Celsius for 1 hour and then at 150 degrees Celsius for 3 hours to solidify the glue mixed with phosphor.

[0089] The color point coordinates of the three LED lamp beads and the target sunlight-like white light color point coordinates are: A (0.1668, 0.2703), B (0.4113, 0.4981), and C (0.5832, 0.3919).

[0090] Substitute the target sunlight-like white light color point coordinates W(x W ,y W ) into formula (2) to obtain the luminous flux of each LED lamp bead under different target sunlight-like white light color points, and obtain the mixed light source information as shown in Table 1.

[0091] Table 1

[0092] CCT 2732 2975 3477 x w ]]> 0.461 0.440 0.407 [[ y w ]]> 0.415 0.405 0.392 RA 95.3 98.5 96.5 R1 96.8 99.1 95.5 R2 95.7 99.4 97.4 R3 91.7 95.2 98.3 R4 97.2 98.0 95.6 R5 95.3 99.6 95.8 R6 92.9 98.6 96.7 R7 97.4 98.7 97.6 R8 95.7 99.0 94.7 R9 86.9 98.7 88.6 R10 87.7 96.5 95.5 R11 97.1 97.8 94.6 R12 85.9 96.6 95.0 R13 96.2 99.4 95.6 R14 94.5 96.6 98.5 R15 96.3 99.0 95.2

[0093] In Table 1, CCT is the correlated color temperature, which refers to the temperature of a hypothetical black body that radiates light matching the color of the light emitted by the light source being measured, and the point on the vertical line of black body radiation. Its unit is Kelvin (K), and its calculation formula is

[0094] CCT = -437n 3 + 3601n 2 - 6831n + 5517

[0095] In the formula, n = (x-0.3320) / (y-0.1858), where (x, y) is the coordinate of the light source being measured in the CIE1931 color coordinate diagram, and CCT is the correlated color temperature.

[0096] The color rendering index (CRI) is an indicator that measures the accuracy and consistency of colors displayed by a light source, and is commonly used to evaluate the quality of artificial light sources. A higher CRI (0-100) indicates that the colors displayed by the light source are closer to natural colors, and the better its color rendering performance. It is calculated by comparing the color difference between a standard light source and the test light source in 15 standard colors. The formulas for various specific CRIs are as follows:

[0097] R i =100-4.6ΔE i (i = 1, ..., 15)

[0098] The color rendering index R is typically used. a Measuring the color rendering performance of a light source

[0099]

[0100] In this embodiment, the comparison diagram of the mixed solar white light spectrum of the three-color LED beads at low color temperatures of 2700K-3500K is shown below. Figure 5 As shown, Figure 5 (1) The spectral curves (relative optical power spectral density functions) corresponding to points A, B, and C; Figure (2) is a comparison of the relative spectrum of a solar-like LED and a traditional LED at a color temperature of 2700K; Figure (3) is a comparison of the relative spectrum of a solar-like LED and a traditional LED at a color temperature of 3000K; Figure (4) is a comparison of the relative spectrum of a solar-like LED and a traditional LED at a color temperature of 3500K. According to... Figure 5 It is known that in the low color temperature range of 2700K-3500K, the solar-like LED light source has a more complete and continuous spectrum than the traditional LED light source, with no blue light emanating from it, making it a healthy, high-quality, full-spectrum solar-like lighting source.

[0101] Example 2

[0102] An LED light assembly for generating sunlight-like white light is basically the same as in Example 1, but the ratio of powder to binder and the proportion of phosphor in the LED beads are adjusted to give more emphasis to the quality of the light source at high color temperatures.

[0103] The powder-to-gum ratio of lamp bead A is 1:4.6; the powder-to-gum ratio of lamp bead B is 1:10, the ratio of green fluorescent powder to yellow fluorescent powder is 2:5; the powder-to-gum ratio of lamp bead C is 1:3, the ratio of yellow fluorescent powder to short-wavelength red fluorescent powder is 16:4:5; the lamp beads are baked at 80 degrees Celsius for 1 hour and then at 150 degrees Celsius for 3 hours to solidify the mixture of glue and fluorescent powder after the test by the far-field integrating sphere test, the lamp bead color point coordinates A (0.1668, 0.2682), B (0.4388, 0.4664), and C (0.5804, 0.3942) are obtained according to step 1, and the target color point coordinates are brought into the relative luminous flux spectral density function to obtain the luminous flux of various color lamp beads according to step three, and the mixed light source information is shown in Table 2:

[0104] Table 2

[0105]

[0106]

[0107] In this embodiment, the comparison chart of the mixed sun-like white light spectrum of the three-color lamp bead with high color temperature 4000K-6500K is shown in FIG. 6, Figure 6 (1) is the spectrum curve (relative luminous flux spectral density function) corresponding to the A, B, and C points; FIG. (2) is a comparison chart of the relative spectrum of the sun-like light LED and the relative spectrum of the traditional LED at a color temperature of 4000K; FIG. (3) is a comparison chart of the relative spectrum of the sun-like light LED and the relative spectrum of the traditional LED at a color temperature of 5000K; FIG. (4) is a comparison chart of the relative spectrum of the sun-like light LED and the relative spectrum of the traditional LED at a color temperature of 6500K, according to Figure 6 It can be seen that, in the high color temperature range of 4000K-6500K, compared with the traditional LED light source, the sun-like light LED light source has a peak wavelength of about 480nm in the blue light part, which provides a wider blue light band at high color temperature, and the 480nm band is not concave, the whole is more complete and continuous, and the light source property is similar to that of sunlight.

[0108] Embodiment 3

[0109] A white light LED mixed light system includes four kinds of LED lamp beads; wherein the packaging structure of each LED lamp bead is basically the same as that of embodiment 1, and the four-color lamp bead can adjust the light to a wider range of high-quality sun-like white light.

[0110] The combination of the chip and the fluorescent powder selected in this embodiment is as follows:

[0111] The lamp bead A uses a LED chip with a peak wavelength of 415nm, and the blue fluorescent powder has an emission spectrum peak wavelength of 483nm and a half peak width of 86nm.

[0112] The lamp bead B uses a LED chip with a peak wavelength of 430 nm to be packaged alone.

[0113] The lamp bead C uses a LED chip with a peak wavelength of 445 nm to excite a green phosphor with a peak wavelength of 529 nm and a half peak width of 106 nm in an emission spectrum, and a yellow phosphor with a peak wavelength of 574 nm and a half peak width of 129 nm in an emission spectrum.

[0114] The lamp bead D uses a LED chip with a peak wavelength of 460 nm to excite a yellow phosphor with a peak wavelength of 574 nm and a half peak width of 129 nm in an emission spectrum, a short-wavelength red phosphor with a peak wavelength of 627 nm and a half peak width of 76 nm in an emission spectrum, and a long-wavelength red phosphor with a peak wavelength of 684 nm and a half peak width of 92 nm in an emission spectrum.

[0115] Solder paste is applied on the bracket, the LED chip is placed on the heating platform at 260 degrees Celsius to fix the chip, AB glue mixed with phosphor is used for covering, the powder-to-glue ratio of the lamp bead A is 1:3.5, the lamp bead B is packaged alone, the powder-to-glue ratio of the lamp bead C is 1:4, the ratio of the green phosphor to the yellow phosphor is 2:3, the powder-to-glue ratio of the lamp bead D is 1:2, and the ratio of the yellow phosphor to the short-wavelength red phosphor to the long-wavelength red phosphor is 8:2:3. After testing by using a far-field integrating sphere, the lamp beads are baked at 80 degrees Celsius for 1 hour and then at 150 degrees Celsius for 3 hours to solidify the glue mixed with the phosphor.

[0116] The color point coordinates of four LED lamp beads and the target sunlight-like white light color point coordinates are A(0.1673, 0.2726), B(0.1667, 0.0138), C(0.4420, 0.5010), and D(0.6323, 0.3619).

[0117] The target sunlight-like white light color point coordinates W(x W ,y W ) are substituted into formula (2) to obtain the luminous flux of each LED lamp bead under different target sunlight-like white light color points, and the mixed light source information is shown in Table 3.

[0118] Table 3

[0119]

[0120]

[0121] In this embodiment, the four-color lamp bead 3000K-6500K mixed sunlight-like white light spectrum is shown in FIG. 1. Figure 7

[0122] Figure 7 ​(a) is 2700K; (b) is 3000K; (c) is 3500K; (d) is 4000K; (e) is 5000K; (f) is 6500K.

[0123] According to Figure 7 As shown in Table 1 and Table 3, the problem of the lack of blue light band in the spectrum of the traditional LED is effectively solved, so that the spectrum of the mixed light source is complete and continuous, and is similar to the spectrum of natural light, so that the color rendering index is greater than 98 along the blackbody radiation line with the dimming color temperature of 2700-6500K, R9-R15 is greater than 90, the spectrum is more complete and continuous compared with the ordinary high color rendering index LED, and the method has certain significance for the field of healthy lighting.

[0124] Compared with the prior art, the present application has at least one of the following advantages or at least part of one advantage:

[0125] (1) The method for generating sun-like white light provided by the present application uses multi-peak wavelength LED chips and fluorescent powder to mix and dim, selects appropriate LED chips and fluorescent powder to cover the entire visible light band, splits the LED chips into multiple, each lamp bead excites corresponding fluorescent powder with different wavelength LED chips to generate a combined light source, and mixes by adjusting the luminous flux of each LED lamp bead, superimposes the spectrum, obtains sun-like white light which is closer to the spectrum of sunlight, and the spectrum characteristics are similar to those of sunlight, the short-wavelength blue light hazard is removed, the purple light does not protrude, and the blue and indigo are not depressed.

[0126] (2) The technical solution provided by the present application selects different color points from the blackbody radiation line in the dimming area to calculate different luminous flux parameter combinations, that is, different luminous flux parameters correspond to sun-like white light with different color temperatures, and by changing the luminous flux (selecting different luminous flux parameter combinations), the dimming and color adjustment along the blackbody radiation line are realized, and the problem of unadjustable dimming color temperature of the traditional single LED chip is solved.

[0127] (3) The LED lamp group for generating sun-like white light provided by the present application is individually packaged with 480nm fluorescent powder, which avoids the problem that the emission spectrum of 480nm fluorescent powder overlaps with the excitation spectrum of long-wavelength fluorescent powder, and the 480nm wave band of the spectrum is absorbed and depressed.

[0128] Although some embodiments of the present general inventive concept have been shown and described, it will be apparent to those having ordinary skill in the art that changes can be made in these embodiments without departing from the principles and spirit of the present general inventive concept, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A method of hybrid LED production of sun-like white light, characterized in that, The method comprises the following steps: 1) selecting m color points in a CIE1931 color coordinate diagram, m≥3, m∈Z, and forming a dimming region with the m color points as vertices, wherein the dimming region comprises all or part of blackbody radiation lines in a color temperature range of 2700K-6500K; 2) determining m peak wavelengths as peak wavelengths of m LED chips in a 400nm-460nm wavelength range according to the selected m color points, and selecting n peak wavelengths as peak wavelengths of n phosphor powders in a 460nm-700nm wavelength range; m≤n≤5, n∈Z; The determination of the m peak wavelengths and the n peak wavelengths both satisfy the following first rule: wherein λ P1 , λ P2 are two adjacent peak wavelengths, |λ P2 - λ P1 | is the absolute value of the difference between the two adjacent peak wavelengths, Δλ1, Δλ2 are the half-peak widths of the LED chip or phosphor corresponding to the peak wavelengths λ P1 , λ P2 , respectively. 3) independently packaging each LED chip in the m LED chips with 0-n phosphor powders selected from the n phosphor powders to obtain m LED lamp beads, wherein the light emitted by the m LED lamp beads in a powered state corresponds to the m color points; The selection of each LED chip from the n phosphor powders needs to satisfy the following second rule: The emission spectrum wavelength range of the LED chip is within the excitation spectrum wavelength range of the phosphor powder; 4) determining l target sunlight-like white light color points on the blackbody radiation lines in the dimming region, and calculating the luminous flux of each LED lamp bead in the m LED lamp beads for each target sunlight-like white light color point to obtain l groups of luminous flux parameters; 5) selecting a group of luminous flux parameters from the l groups of luminous flux parameters according to a preset target, and using the group of luminous flux parameters to control the m LED lamp beads to form mixed light, i.e., sunlight-like white light.

2. The method of hybrid production of a sun-like white light by LEDs according to claim 1, characterized in that, The calculation of the luminous flux of each LED lamp bead in the m LED lamp beads for each target sunlight-like white light color point is specifically: selecting a target sunlight-like white light color point, and calculating the luminous flux of the m LED lamp beads according to the m color points, the target sunlight-like white light color point, and a preset target sunlight-like white light luminous flux.

3. The method of hybrid production of a sun-like white light by LEDs according to claim 2, characterized in that, When m is 3, the coordinates of the three color points are A(x A ,y A ), B(x B ,y B ), and C(x C ,y C ), and the coordinates of the target type sun white light color point are W(x W ,y W ), and the luminous fluxes of the three LED lamp beads are calculated according to the following formula: Wherein, φ W is the light flux of the preset target class solar white light; φ A , φ B , φ C are the light fluxes of the three LED lamp beads.

4. The method of hybrid production of a sun-like white light by LEDs according to claim 1, characterized in that, The n phosphor powders comprise a phosphor powder with a peak wavelength range of 470nm-490nm, and the phosphor powder with the peak wavelength range of 470nm-490nm is independently packaged in combination with an LED chip with the smallest peak wavelength in the m LED chips.

5. An LED lamp group for generating sunlight-like white light, characterized in that, The LED lamp group comprises m LED lamp beads, m≥3, m∈Z; each LED lamp bead is independently packaged, each LED lamp bead comprises one LED chip and 0-n phosphor powders, n∈Z, m≤n≤5, the color point of each LED lamp bead is selected from a region around a blackbody radiation line in a CIE1931 color coordinate diagram, and the peak wavelength of the LED chip comprised by each LED lamp bead is different; In a 400nm-460nm wavelength range, m peak wavelengths are determined as peak wavelengths of m LED chips according to m selected color points; in a 460nm-700nm wavelength range, n peak wavelengths are selected as peak wavelengths of n phosphor powders; The determination of the m peak wavelengths and the n peak wavelengths both satisfy the following first rule: wherein λ P1 , λ P2 are two adjacent peak wavelengths, |λ P2 - λ P1 | is the absolute value of the difference between the two adjacent peak wavelengths, Δλ1, Δλ2 are the full widths at half maximum of the LED chip or phosphor corresponding to the peak wavelengths λ P1 , λ P2 , respectively. Each of the LED lamp beads is configured to emit light of a corresponding color point by the LED chip contained therein or to excite a corresponding phosphor to emit light of a corresponding color point by the LED chip contained therein under a set luminous flux; In the LED lamp bead, the emission spectrum band of the LED chip is within the excitation spectrum band of the phosphor.

6. The LED lamp set for generating a quasi-solar white light according to claim 5, characterized in that, The peak wavelength of the LED chip is between 400 nm and 460 nm, and the peak wavelength range of the phosphor is between 470 nm and 505 nm at the lowest and between 660 nm and 690 nm at the highest.

7. The LED lamp set for generating sunlight-like white light according to claim 5, wherein, The peak wavelengths of the LED chips contained in the m LED lamp beads are separated by between 10 nm and 20 nm.

8. The LED lamp set for generating sun-like white light according to claim 5, characterized in that, The first LED lamp bead included in the m LED lamp beads has a phosphor with a peak wavelength range of 470 nm to 490 nm.

9. The LED lamp set for generating sun-like white light according to claim 5, characterized in that, The LED lamp set includes a first LED lamp bead, a second LED lamp bead, and a third LED lamp bead. The peak wavelength of the LED chip in the first LED lamp bead is 415 nm to 420 nm, the phosphor is excited at a peak wavelength of 480 nm to 490 nm, and the ratio of the peak intensity of the LED to the peak intensity of the phosphor is 1:1.5 to 1:

4. The peak wavelength of the LED chip in the second LED lamp bead is 430 nm to 435 nm, the phosphor is excited at a peak wavelength of 520 nm to 540 nm and 560 nm to 580 nm, and the ratio of the peak intensity of the LED chip to the peak intensity of the phosphor is 1:1:1 to 1:3:

3. The peak wavelength of the LED chip in the third LED lamp bead is 445 nm to 455 nm, the phosphor is excited at a peak wavelength of 560 nm to 580 nm, 615 nm to 635 nm, and 660 nm to 690 nm, and the ratio of the peak intensity of the LED to the peak intensity of the phosphor is 1:7:7:9 to 1:14:20:

50.

10. The LED lamp set for generating sun-like white light according to claim 5, characterized in that, The LED lamp set includes a first LED lamp bead, a second LED lamp bead, a third LED lamp bead, and a fourth LED lamp bead. The color point of the first LED lamp bead is A (0.1673, 0.2726), the peak wavelength of the LED chip contained therein is 415 nm, the phosphor is excited at a peak wavelength of 483 nm, and the ratio of the peak intensity of the LED to the peak intensity of the phosphor is 1:

2. The color point of the second LED lamp bead is B (0.1667, 0.0138), the peak wavelength of the LED chip contained therein is 430 nm. The color point of the third LED lamp bead is C (0.4420, 0.5010), the peak wavelength of the LED chip contained therein is 445 nm, the phosphor is excited at a peak wavelength of 530 nm and 574 nm, and the ratio of the peak intensity of the LED to the peak intensity of the phosphor is 1:2.4:3.

2. ​ The color point of the fourth LED lamp bead is D (0.6323, 0.3619), the peak wavelength of the LED chip contained is 460 nm, the fluorescent powder with the excitation peak wavelength of 574 nm, 627 nm and 684 nm is excited, and the ratio of the LED peak intensity to the fluorescent powder peak intensity is 1:10:70:100.

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