A full-spectrum healthy lighting light-emitting diode and its phosphor formulation method

Abstract

This invention relates to the field of light-emitting diode (LED) technology and discloses a full-spectrum healthy lighting LED and its phosphor formulation method. The method includes: S1: measuring the spectral radiant flux and phosphor conversion parameters of a blue LED chip; S2: calculating the green, yellow, and red light fluxes based on the spectral radiant flux and phosphor conversion parameters, and setting formulation constraint parameters; S3: calculating the spectral proportion parameter based on a first mass proportion and generating a second mass proportion; S4: weighing and mixing green, yellow, and red phosphors according to the second mass proportion to obtain a mixed phosphor; S5: mixing the mixed phosphor with a silicone substrate and then dotting it onto the surface of the blue LED chip for curing to obtain an LED device. This invention realizes the calculation and control of green, yellow, and red light fluxes, solving the technical problem of spectral discontinuity in traditional single phosphor schemes.

Description

Technical Field

[0001] This invention relates to the field of light-emitting diode technology, and in particular to a full-spectrum healthy lighting light-emitting diode and its phosphor formulation method. Background Technology

[0002] Traditional white LED lighting uses a blue LED chip to excite a single yellow phosphor. While this achieves basic white light output, it suffers from spectral defects. Significant spectral energy gaps occur in the 480-500nm cyan-green region and the 620-680nm deep red region, resulting in a discontinuous spectral distribution and an inability to achieve uniform coverage across the entire 380-780nm wavelength range. This spectral fragmentation directly impacts lighting quality and visual comfort. Furthermore, the limited absorption and conversion efficiency of a single phosphor formulation for blue light leads to an excessively high proportion of residual blue light in the LED device's output spectrum, typically reaching 30-35%. Long-term use poses a risk of blue light hazard and does not meet the demands of healthy lighting development. Summary of the Invention

[0003] This invention provides a full-spectrum healthy lighting light-emitting diode and its phosphor formulation method. This invention realizes the calculation and control of green light flux, yellow light flux and red light flux, and solves the technical problem of spectral discontinuity in traditional single phosphor schemes.

[0004] In a first aspect, the present invention provides a phosphor formulation method for a full-spectrum healthy lighting light-emitting diode, the phosphor formulation method for the full-spectrum healthy lighting light-emitting diode comprising: S1: Measure the spectral radiant flux and phosphor conversion parameters of the blue light-emitting diode chip; S2: Calculate the green light flux, yellow light flux, and red light flux based on the spectral radiant flux and the phosphor conversion parameters, and set the ratio constraint parameters; S3: Calculate the spectral proportion parameter based on the first mass proportion, and generate the second mass proportion according to the spectral proportion parameter and the ratio constraint parameter; S4: Weigh out green phosphor, yellow phosphor and red phosphor according to the second mass ratio and mix them to obtain mixed phosphor; S5: The mixed phosphor is mixed with the silicone substrate and then dotted onto the surface of the blue light-emitting diode chip and cured to obtain a light-emitting diode device.

[0005] In conjunction with the first aspect, in a first implementation of the first aspect of the present invention, step S1 includes: S11: Perform spectral measurement on the blue light-emitting diode chip under a preset driving current, record the spectral intensity data of the blue light band, and extract the spectral radiant flux. S12: Excitation spectra and quantum efficiency measurements are performed on green phosphor, yellow phosphor, and red phosphor in the blue light band to obtain phosphor conversion parameters, including the first absorption cross-sectional coefficient and first quantum efficiency of green phosphor, the second absorption cross-sectional coefficient and second quantum efficiency of yellow phosphor, and the third absorption cross-sectional coefficient and third quantum efficiency of red phosphor.

[0006] In conjunction with the first aspect, in a second implementation of the first aspect of the present invention, step S2 includes: S21: Multiply the spectral radiant flux by the mass ratio of green phosphor, the first absorption cross-sectional coefficient, and the first quantum efficiency to obtain the green light flux; S22: Multiply the spectral radiant flux by the mass ratio of the yellow phosphor, the second absorption cross-sectional coefficient, and the second quantum efficiency to obtain the yellow light flux; S23: Multiply the spectral radiant flux by the mass ratio of the red phosphor, the third absorption cross-section coefficient, and the third quantum efficiency to obtain the red light flux; S24: Calculate the proportion of cyan-green light band, the proportion of deep red light band, and the proportion of blue residual light based on the green light flux, the yellow light flux, and the red light flux. Set the proportion of cyan-green light band to be greater than or equal to a first threshold, the proportion of deep red light band to be greater than or equal to a second threshold, and the proportion of blue residual light to be less than or equal to a third threshold to obtain the ratio constraint parameters.

[0007] In conjunction with the first aspect, in a third implementation of the first aspect of the present invention, step S21 includes: S211: Multiply the spectral radiant flux by the mass ratio of the green phosphor and the first absorption cross-sectional coefficient to obtain the blue light energy absorbed by the green phosphor; S212: Multiply the blue light energy absorbed by the green phosphor by the first quantum efficiency to obtain the green light flux.

[0008] In conjunction with the first aspect, in a fourth implementation of the first aspect of the present invention, step S24 includes: S241: Add the green light flux, the yellow light flux, the red light flux, and the blue residual light flux to obtain the total light flux; S242: Divide the green light flux by the total light flux to obtain the first cyan-green light band ratio; divide the red light flux by the total light flux to obtain the first deep red light band ratio; divide the blue light residual flux by the total light flux to obtain the first blue light residual ratio. S243: Set the proportion of the first cyan-green light band to be greater than or equal to the first threshold, the proportion of the first deep red light band to be greater than or equal to the second threshold, and the proportion of the first blue light residue to be less than or equal to the third threshold to obtain the ratio constraint parameters.

[0009] In conjunction with the first aspect, in a fifth implementation of the first aspect of the present invention, step S3 includes: S31: Calculate the spectral proportion parameters based on the first mass proportion, the spectral proportion parameters including the proportion of the second cyan-green light band, the proportion of the second deep red light band, and the proportion of the second blue light residue; S32: Determine whether the proportion of the second cyan-green light band is less than the first threshold, whether the proportion of the second deep red light band is less than the second threshold, and whether the proportion of the second blue light residue is greater than the third threshold, and determine the type of phosphor that needs to be adjusted; S33: If the proportion of the second cyan-green light band is less than the first threshold, then the mass proportion of the green phosphor is increased by a preset first increment. If the proportion of the second deep red light band is less than the second threshold, then the mass proportion of the red phosphor is increased by a preset second increment. The sum of the first increment and the second increment is subtracted from the mass proportion of the yellow phosphor to obtain the second mass proportion.

[0010] In conjunction with the first aspect, in the sixth implementation of the first aspect of the present invention, step S33 includes: S331: If the proportion of the second cyan-green light band is less than the first threshold, then the mass proportion of the green phosphor is increased by a preset first increment; if the proportion of the second deep red light band is less than the second threshold, then the mass proportion of the red phosphor is increased by a preset second increment. S332: Add the first increment and the second increment to obtain the total adjustment; S332: Add the mass percentage of green phosphor to the corresponding first increment, add the mass percentage of red phosphor to the corresponding second increment, and subtract the total adjustment amount from the mass percentage of yellow phosphor to obtain the second mass percentage.

[0011] In conjunction with the first aspect, in the seventh implementation of the first aspect of the present invention, step S4 includes: S41: Weigh the green phosphor, the yellow phosphor, and the red phosphor according to the second mass ratio, and screen the phosphor particles that meet the preset requirements; S42: The screened phosphor particles are placed into a ball mill and dry-mixed at a preset speed to obtain mixed phosphor.

[0012] In conjunction with the first aspect, in the eighth implementation of the first aspect of the present invention, step S5 includes: S52: The mixed phosphor and the silicone matrix are mixed and then placed in a vacuum degassing machine for degassing under negative pressure to obtain a phosphor-silicone mixture. S53: The phosphor-silicone mixture is applied to the surface of the blue light-emitting diode chip at a preset dosage and then cured at a preset temperature for a preset time to obtain a light-emitting diode device.

[0013] Secondly, the present invention provides a full-spectrum healthy lighting light-emitting diode, wherein the full-spectrum healthy lighting light-emitting diode is used to perform the above-described phosphor mixing method for the full-spectrum healthy lighting light-emitting diode.

[0014] The technical solution provided by this invention combines the mass ratios of green, yellow, and red phosphors with their respective absorption cross-sectional coefficients and quantum efficiencies to achieve the calculation and control of green, yellow, and red light fluxes, solving the technical problem of spectral discontinuity in traditional single-phosphor solutions. By setting ratio constraint parameters such as a proportion of cyan-green light greater than or equal to a first threshold, a proportion of deep red light greater than or equal to a second threshold, and a blue light residue proportion less than or equal to a third threshold, a quantitative evaluation standard for full-spectrum healthy lighting is established, ensuring that the spectral energy in the 480-500nm cyan-green light region and the 620-680nm deep red light region is effectively supplemented. The phosphor mass ratios are dynamically optimized based on the matching of the spectral proportion parameters and the ratio constraint parameters. By increasing the proportion of green and red phosphors while correspondingly reducing the proportion of yellow phosphor, effective control of the blue light residue proportion and improvement of spectral continuity are achieved. By controlling the phosphor particle size distribution and employing a dry mixing process, the uniform dispersion of multi-band phosphors in the silicone matrix and the uniform absorption and conversion of blue light are ensured, resulting in healthy lighting LED devices with full-spectrum coverage, low blue light hazard, and high color rendering performance. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram illustrating the steps of the phosphor mixing method for a full-spectrum healthy lighting light-emitting diode in an embodiment of the present invention; Figure 2 This is a comparison chart of the spectral distribution of the traditional formulation and the formulation of the present invention in the embodiments of the present invention; Figure 3 This is a graph showing the change of spectral proportion parameters during the iterative adjustment of the proportion in an embodiment of the present invention. Figure 4 This is a bar chart comparing the color rendering performance and blue light safety of different formulation schemes in the embodiments of the present invention. Figure 5 This is a schematic diagram of the downconversion energy transfer of blue light-excited multi-band phosphor in an embodiment of the present invention. Detailed Implementation

[0017] This invention provides a full-spectrum healthy lighting light-emitting diode and a method for phosphor formulation thereof. The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein. Furthermore, the terms "comprising" or "having" and any variations thereof are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0018] For ease of understanding, the specific process of the embodiments of the present invention is described below. Please refer to [link / reference]. Figure 1 One embodiment of the phosphor formulation method for full-spectrum healthy lighting LEDs in this invention includes: S1: Measure the spectral radiant flux and phosphor conversion parameters of the blue light-emitting diode chip; Specifically, the spectral radiation of the blue light-emitting diode chip was measured under constant driving conditions. Under a constant driving current of 20mA, the full spectrum radiation intensity distribution data from 380nm to 780nm was obtained using an integrating sphere spectral system, and high-resolution spectral intensity curves from 450nm to 460nm blue light band were extracted. The spectral radiant flux Φ0 of the blue light chip was calculated with a sampling interval of 1nm as the excitation input energy reference, and its peak wavelength λ0 and full width at half maximum Δλ were extracted to evaluate its energy concentration, ensuring that the chip output meets the requirements of high excitation efficiency. The blue light excitation response characteristics of green, yellow, and red phosphors were measured using a fluorescence spectrometer and a quantum efficiency testing device. Specifically, the excitation spectra of the three phosphors were scanned within the dominant blue light wavelength range of the chip (e.g., 455 nm ± 5 nm) to obtain their excitation peak positions, excitation bandwidths, and excitation intensity distributions in the blue light band. Using an integral excitation method combined with a luminous flux calibration device, the internal quantum efficiencies ηg, ηy, and ηr of the three phosphors under corresponding blue light excitation conditions were measured, corresponding to the luminous conversion efficiencies of the green, yellow, and red phosphors, respectively. Simultaneously, by measuring their light absorption capacity and combining the incident blue light power to absorption energy ratio, the average absorption cross-sectional coefficients αg, αy, and αr of the three phosphors in the dominant blue light band were calculated. These were used as the first, second, and third absorption cross-sectional coefficients, respectively, constituting a set of phosphor conversion parameters, including the first absorption cross-sectional coefficient and first quantum efficiency of the green phosphor, the second absorption cross-sectional coefficient and second quantum efficiency of the yellow phosphor, and the third absorption cross-sectional coefficient and third quantum efficiency of the red phosphor.

[0019] Figure 2 This is a comparison of the spectral distribution of the traditional formulation and the formulation of this invention. The dashed line represents the spectral distribution of the traditional blue LED excited by a single yellow phosphor (YAG), showing a 480-500nm cyan-green spectral valley between the 450nm blue peak and the 560nm yellow peak, and a severe energy deficiency in the 620-680nm deep red region. The solid line represents the spectral distribution of this invention, which uses a blue LED to synergistically excite green, yellow, and red phosphors, forming green, yellow, and red peaks at 530nm, 560nm, and 630nm respectively, achieving continuous full-spectrum coverage in the 380-780nm band. Simultaneously, blue light residue is reduced to a suitable level at 450nm, solving the spectral blockage and blue light hazard problems of the traditional solution.

[0020] S2: Calculate the green light flux, yellow light flux, and red light flux based on the spectral radiant flux and phosphor conversion parameters, and set the ratio constraint parameters; Specifically, an arbitrary initial green phosphor mass ratio parameter wg is selected and multiplied by the total radiant flux Φ0 of the blue light chip, the first absorption cross-section coefficient αg of the green phosphor in the blue light band, and the first quantum efficiency ηg to obtain the green light conversion flux Φg = Φ0 × wg × αg × ηg; the mass ratio wy of the yellow phosphor, the second absorption cross-section coefficient αy, and the second quantum efficiency ηy are substituted into the flux model to obtain the yellow light flux Φy = Φ0 × wy × αy × ηy; the mass ratio wr of the red phosphor, the third absorption cross-section coefficient αr, and the third quantum efficiency ηr are substituted into the model to obtain the red light flux Φr = Φ0 × wr × αr × ηr. When calculating the blue light residual flux, the overall absorption ratio of the three phosphors to blue light is estimated based on their mass ratios and corresponding absorption cross-section coefficients. The difference between the total blue light radiant flux Φ0 and the total absorption is taken as the blue light residual flux Φblue = Φ0 × [1 - (wg × αg + wy × αy + wr × αr)]. Based on the four luminous flux parameters mentioned above, three spectral distribution indices are constructed. The proportion of cyan light (Pcyan) is defined as the ratio of green light flux (Φg) to total luminous flux (Φg+Φy+Φr+Φblue). The proportion of deep red light (Pred) is defined as the ratio of red light flux (Φr) to total luminous flux. The proportion of blue residual light (Rblue) is defined as the ratio of Φblue to total luminous flux. In the setting process, combined with human-caused lighting requirements and photobiological safety standards, a first threshold of 0.18 is set to limit the proportion of cyan light, a second threshold of 0.22 is set to ensure deep red light energy coverage, and a third threshold of 0.25 is set to control the proportion of blue residual light from exceeding the exemption-level safety limit, thus forming a set of proportion constraint parameters.

[0021] S3: Calculate the spectral proportion parameter based on the first mass proportion, and generate the second mass proportion according to the spectral proportion parameter and the ratio constraint parameter; Specifically, by substituting the initial mass proportions wg, wy, and wr into the formulas for calculating the green, yellow, and red light fluxes, respectively, and combining them with the expression for the residual blue light flux, the green light flux Φg, the red light flux Φr, and the residual blue light flux Φblue are obtained. The corresponding proportions of the second cyan-green band, Pcyan=Φg / (Φg+Φy+Φr+Φblue), the proportion of the second deep red band, Pred=Φr / (Φg+Φy+Φr+Φblue), and the proportion of the second residual blue light, Rblue=Φblue / (Φg+Φy+Φr+Φblue), are calculated as spectral output characteristic indicators under the current ratio. The three second spectral proportion parameters are compared with the first, second, and third thresholds in the ratio constraint. When Pcyan is less than the first threshold, it indicates insufficient cyan-green light coverage, requiring enhancement of green phosphor. When Pred is less than the second threshold, it indicates insufficient deep red light energy, requiring an increase in the proportion of red phosphor. When Rblue is greater than the third threshold, it indicates excessive blue light residue, requiring an overall improvement in absorption and conversion efficiency. This allows for a comprehensive determination of which phosphor types in the current ratio structure require adjustment. If Pcyan is less than the first threshold, the first increment Δwg is added to the green phosphor mass proportion wg. If Pred is less than the second threshold, the second increment Δwr is added to the red phosphor mass proportion wr. To maintain the normalization constraint that the sum of the three proportions is 1, the sum of Δwg and Δwr is subtracted from the yellow phosphor mass proportion wy, i.e., wy = wy – (Δwg + Δwr), resulting in the new second mass proportions wg' = wg + Δwg, wy' = wy – (Δwg + Δwr), and wr' = wr + Δwr.

[0022] S4: Weigh out green phosphor, yellow phosphor and red phosphor according to the second mass ratio and mix them to obtain mixed phosphor; Specifically, based on the second mass ratio, i.e., the proportions of green, yellow, and red phosphors, corresponding masses of phosphor material are weighed. Particle size distribution is measured for each of the three phosphors using a laser particle size analyzer to obtain particle size parameters such as D10, D50, and D90, and the particle size span coefficient S = (D90 – D10) / D50 is calculated. The requirements are: D50 for green phosphor in the range of 9 to 11 micrometers and S ≤ 0.75; D50 for yellow phosphor in the range of 10 to 12 micrometers and S ≤ 0.80; and D50 for red phosphor in the range of 8 to 10 micrometers and S ≤ 0.70. If a phosphor does not meet the particle size window limit, particle size control is performed. Particles with excessively large D50 are reduced in size using air jet milling or wet grinding, while particles with excessively small D50 are removed by centrifugation or sedimentation to remove fine powder, ensuring that the phosphor particles used for mixing have a qualified particle size distribution and optical excitation response capability. Three types of qualified phosphor particles were added to a dry mixing system in an optimized ratio. A planetary ball mill was used as the mixing device, and dry ball milling was performed for 15 to 20 minutes at a set speed (e.g., 300 rpm). High-speed shearing and tumbling stirring were used to achieve efficient and uniform distribution of phosphors with different particle sizes and densities. After mixing, the particle size distribution uniformity of the resulting mixed phosphor sample was measured, and its coefficient of variation (CV) was calculated as (standard deviation / average particle size) × 100%. The CV was required to be no greater than 15%.

[0023] S5: Mix the mixed phosphor with the silicone matrix and then apply it to the surface of the blue light-emitting diode chip for curing to obtain the light-emitting diode device.

[0024] Specifically, the mixed phosphor and silicone matrix material are fully composited and residual air bubbles are eliminated to ensure uniform material distribution and defect-free interfaces during encapsulation. The mixed phosphor with uniform proportions and acceptable particle size distribution is mixed with the silicone matrix material at a mass ratio of 1:3. The silicone matrix is ​​preferably a two-component addition-type system, where component A contains vinyl-terminated polydimethylsiloxane, and component B contains a hydrogen-containing siloxane crosslinking agent and a platinum-based catalyst. Components A and B are premixed in a 1:1 ratio and then rapidly added to the mixed phosphor. Mechanical stirring is used to form a uniformly dispersed composite. To remove microbubbles and pores introduced during stirring, the mixture is placed in a vacuum degassing machine and continuously degassed for 10 minutes under a negative pressure of -0.09 MPa. The pressure difference between the inside and outside of the gas causes microbubbles to escape, resulting in a homogeneous, bubble-free phosphor-silicone mixture. The prepared phosphor-silicone mixture is quantitatively applied to the surface of a blue light-emitting diode (LED) chip at a preset dosage (e.g., 0.02 mL) using a high-precision dispensing machine. The typical chip size is 1 mm × 1 mm, and a constant current of 20 mA is used for driving. The dispensing process requires stable viscosity and good material spreadability to ensure uniform encapsulation layer thickness and complete coverage. Immediately after coating, the sample is placed in a preset temperature environment for thermosetting, and held at 150°C for 1 hour to allow the silicone to undergo a cross-linking reaction and achieve structural stabilization, resulting in a stable encapsulated LED device.

[0025] In one specific embodiment, the process of performing step S1 may specifically include the following steps: S11: Perform spectral measurement on the blue light-emitting diode chip under a preset driving current, record the spectral intensity data of the blue light band, and extract the spectral radiant flux. S12: Excitation spectra and quantum efficiency measurements were performed on green phosphor, yellow phosphor, and red phosphor in the blue light band to obtain phosphor conversion parameters, including the first absorption cross-sectional coefficient and first quantum efficiency of green phosphor, the second absorption cross-sectional coefficient and second quantum efficiency of yellow phosphor, and the third absorption cross-sectional coefficient and third quantum efficiency of red phosphor.

[0026] Specifically, a blue LED chip testing platform was established. During the experiment, the blue LED chip was fixed on a test base with constant temperature and heat dissipation function, and powered by a high-precision source meter under typical driving conditions (such as a 20mA forward driving current). Simultaneously, an integrating sphere spectral measurement system was connected to the chip's radiation output terminal to perform full-band spectral scanning sampling from 380nm to 780nm. During the scanning process, the spectral intensity distribution within the blue light region (450nm to 460nm) was recorded point-by-point at 1nm sampling intervals. The peak wavelength λ0 and full width at half maximum (FWHM) Δλ of the chip were extracted to evaluate its spectral concentration, and the total spectral radiant flux Φ0 in this band was extracted through integration. Blue light excitation response analysis was conducted for three different chromophore materials. A fluorescence spectrometer was used to measure the excitation spectrum of each phosphor under the main blue light band (e.g., 455nm ± 5nm). By adjusting the excitation wavelength scanning input, the luminescence intensity response curve in the visible light emission band (500nm~700nm) was recorded, and the absolute response value was obtained in conjunction with a calibrated light source. A quantum efficiency measurement system was used to perform photoexcitation experiments on each phosphor sample, measuring its fluorescence output power under standard blue light incident power. The quantum efficiency η, i.e., the proportion of emitted photons per unit of absorbed photons, was calculated based on the energy conservation principle. By measuring the difference between the incident light power and the transmitted light power before and after absorption, the average absorption efficiency within the blue light main band was calculated. Combined with the phosphor density and effective cross-sectional area, the average absorption cross-sectional coefficient α was derived. αg and ηg corresponding to green phosphor were used as the first absorption cross-sectional coefficient and the first quantum efficiency; αy and ηy corresponding to yellow phosphor were used as the second absorption cross-sectional coefficient and the second quantum efficiency; and αr and ηr corresponding to red phosphor were used as the third absorption cross-sectional coefficient and the third quantum efficiency, thus constructing the phosphor conversion parameter set.

[0027] The process includes a phosphor excitation matching degree evaluation step between steps S1 and S2: The spectral radiation distribution of the blue LED chip is compared with the excitation spectra of green, yellow, and red phosphors to calculate the band overlap integral, obtaining the green phosphor overlap integral value, yellow phosphor overlap integral value, and red phosphor overlap integral value; the ratio of the green phosphor overlap integral value to the total energy of the blue band is used to calculate the green phosphor excitation matching degree coefficient; the ratio of the yellow phosphor overlap integral value to the total energy of the blue band is used to calculate the yellow phosphor excitation matching degree coefficient; and the ratio of the red phosphor overlap integral value to the total energy of the blue band is used to calculate the red phosphor excitation matching degree coefficient. The excitation matching coefficient of the red phosphor is calculated from the ratio of total energy. An excitation matching threshold is set to a preset value. It is then determined whether the excitation matching coefficients of the green, yellow, and red phosphors are all greater than the excitation matching threshold. If the excitation matching coefficient of any phosphor is less than the excitation matching threshold, the absorption cross-sectional coefficient of that phosphor is corrected by multiplying it by the corresponding excitation matching coefficient to obtain the corrected absorption cross-sectional coefficient. The corrected absorption cross-sectional coefficient is then used to replace the absorption cross-sectional coefficient of the corresponding phosphor in step S2 for luminous flux calculation.

[0028] In one specific embodiment, the process of performing step S2 may specifically include the following steps: S21: Multiply the spectral radiant flux by the mass ratio of green phosphor, the first absorption cross-sectional coefficient, and the first quantum efficiency to obtain the green light flux; S22: Multiply the spectral radiant flux by the mass ratio of the yellow phosphor, the second absorption cross-section coefficient, and the second quantum efficiency to obtain the yellow light flux; S23: Multiply the spectral radiant flux by the mass ratio of the red phosphor, the third absorption cross-section coefficient, and the third quantum efficiency to obtain the red light flux; S24: Calculate the proportion of cyan-green light, the proportion of deep red light, and the proportion of residual blue light based on the green light flux, yellow light flux, and red light flux. Set the proportion of cyan-green light to be greater than or equal to the first threshold, the proportion of deep red light to be greater than or equal to the second threshold, and the proportion of residual blue light to be less than or equal to the third threshold to obtain the proportion constraint parameters.

[0029] Specifically, the total spectral radiant flux Φ0 of the blue LED chip is used as the energy input benchmark. The mass percentage parameters of three phosphors are introduced, namely, the mass percentage of green phosphor wg, the mass percentage of yellow phosphor wy, and the mass percentage of red phosphor wr. At the same time, the first absorption cross-section coefficient αg, the second absorption cross-section coefficient αy, the third absorption cross-section coefficient αr and the corresponding quantum efficiencies ηg, ηy, and ηr are used to construct the conversion flux expression. The green light flux Φg is calculated by Φ0×wg×αg×ηg, the yellow light flux Φy is calculated by Φ0×wy×αy×ηy, and the red light flux Φr is calculated by Φ0×wr×αr×ηr. The above three fluxes represent the downconversion output intensity of blue light energy in the green, yellow, and red bands, respectively. After completing the three-channel flux calculation, the portion of blue light not absorbed by the phosphor, i.e., the residual blue light flux Φblue, is introduced. It is calculated as Φblue = Φ0 × [1 – (wg × αg + wy × αy + wr × αr)], reflecting the direct transmission energy component resulting from incomplete blue light absorption by the phosphor at the current formulation. The four flux values ​​are combined to calculate the total luminous flux Φtotal = Φg + Φy + Φr + Φblue. Based on this, three relative proportion parameters are derived: the proportion of the cyan-green band, Pcyan = Φg / Φtotal, reflecting the distribution of short-wavelength visible green-blue boundary light related to visual comfort; the proportion of the deep red band, Pred = Φr / Φtotal, used to assess the energy coverage of circadian rhythm regulation and the physiological effects of red light; and the residual blue light proportion, Rblue = Φblue / Φtotal, directly corresponding to the constraint index on short-wavelength blue light energy in photobiological safety. The three proportions are compared with preset healthy lighting thresholds. The proportion of cyan light (Pcyan) should be greater than or equal to the first threshold (P1, e.g., 0.18) to compensate for the energy gap of traditional LEDs in the cyan-green region. The proportion of deep red light (Pred) should be greater than or equal to the second threshold (P2, e.g., 0.22) to ensure effective supplementation of the far-red band. The proportion of blue residual light (Rblue) should be less than or equal to the third threshold (P3, e.g., 0.25) to meet the requirements of the IEC 62471 photobiological safety exemption level. The comparison results of the three items are used as the basis for determining whether the current ratio is qualified. If all conditions are met, the current combination of wg, wy, wr with the corresponding Pcyan, Pred, and Rblue is defined as a valid ratio constraint solution. Otherwise, the next round of iteration and update process is entered to adjust the proportions and recalculate until all proportion parameters meet the threshold requirements.

[0030] Figure 4A bar chart comparing the color rendering performance and blue light safety of different formulation schemes is presented. The horizontal axis represents the five formulation schemes, the left side of the vertical axis represents the color rendering index Ra and the color gamut value NTSC (in %), and the right side of the vertical axis represents the percentage of residual blue light (in %). Solid black bars represent the color rendering index Ra, diagonally filled bars represent the color gamut value NTSC, and grid-filled bars represent the percentage of residual blue light. From Scheme A (traditional single yellow phosphor) to Scheme E (the final formulation of this invention), the color rendering index Ra increased from 75 to 93.2, the color gamut value NTSC increased from 68% to 87%, and the percentage of residual blue light decreased from 35% to 21%. The short dashed lines mark the performance target lines of Ra=90 and NTSC=80%. The comparative results show that the multi-band phosphor formulation scheme of this invention simultaneously achieves high color rendering performance and low blue light hazard, and all indicators of Scheme E meet or exceed the healthy lighting standards.

[0031] The process includes a Stokes shift-based spectral continuity optimization step before step S24: The Stokes shift value of the green phosphor is calculated by dividing the peak emission wavelength of the green phosphor by the peak wavelength of the blue LED chip; the Stokes shift value of the yellow phosphor is calculated by dividing the peak emission wavelength of the yellow phosphor by the peak wavelength of the yellow phosphor; and the Stokes shift value of the red phosphor is calculated by dividing the peak emission wavelength of the red phosphor by the peak wavelength of the yellow phosphor. Based on the Stokes shift values ​​of the green, yellow, and red phosphors, the wavelength intervals between the emission peaks of the three phosphors are determined; the first wavelength interval is calculated by dividing the peak emission wavelength of the yellow phosphor by the peak emission wavelength of the green phosphor; and the second wavelength interval is calculated by dividing the peak emission wavelength of the red phosphor by the peak emission wavelength of the yellow phosphor. A spectral continuity evaluation function is established, and the first wavelength interval and the second wavelength interval are calculated. The two wavelength intervals are compared with preset wavelength interval thresholds. If the first wavelength interval is greater than the preset wavelength interval threshold, the mass ratio of green phosphor is increased to fill the gap in the cyan-green light band. If the second wavelength interval is greater than the preset wavelength interval threshold, the mass ratio of red phosphor is increased to fill the gap in the yellow-red light band. The spectral coverage is calculated based on the half-width at half-maximum (WHM) of the emission spectrum of each phosphor. The green light coverage band is obtained by adding or subtracting half the WHM from the emission peak wavelength of the green phosphor. The yellow light coverage band is obtained by adding or subtracting half the WHM from the emission peak wavelength of the yellow phosphor. The red light coverage band is obtained by adding or subtracting half the WHM from the emission peak wavelength of the red phosphor. It is determined whether there is an overlap between the green light coverage band and the yellow light coverage band, and whether there is an overlap between the yellow light coverage band and the red light coverage band. If there is no overlap, the mass ratio of phosphors in adjacent bands is increased until continuous spectral coverage is formed, and the mass ratio parameter after spectral continuity optimization is obtained.

[0032] In one specific embodiment, step S21 includes: S211: Multiply the spectral radiant flux by the mass ratio of the green phosphor and the first absorption cross-section coefficient to obtain the blue light energy absorbed by the green phosphor; S212: The green light flux is obtained by multiplying the blue light energy absorbed by the green phosphor by the first quantum efficiency.

[0033] Specifically, the spectral radiant flux Φ0 measured by the blue light-emitting diode chip under a preset driving current is used as the total excitation energy input. Based on the known mass ratio of green phosphor wg and the first absorption cross-section coefficient αg, the product of these three factors, Φabs,g = Φ0 × wg × αg, represents the blue light energy absorbed by the green phosphor per unit of total flux. This energy portion is controlled only by the mass participation ratio of the green phosphor and its effective absorption capacity for blue light energy. Therefore, αg is obtained by integral averaging over the absorption curve in the 450nm to 460nm wavelength range to truly reflect its absorption efficiency under blue light excitation conditions. Multiplying the blue light energy Φabs,g absorbed by the green phosphor by the first quantum efficiency ηg of the green phosphor, i.e., Φg = Φabs,g × ηg = Φ0 × wg × αg × ηg, yields the actual visible green light flux Φg that the green phosphor can output under this specific ratio condition.

[0034] In one specific embodiment, step S24 includes: S241: Add the green light flux, yellow light flux, red light flux, and blue residual light flux to obtain the total light flux; S242: Divide the green light flux by the total light flux to obtain the proportion of the first cyan-green light band; divide the red light flux by the total light flux to obtain the proportion of the first deep red light band; divide the blue residual flux by the total light flux to obtain the proportion of the first blue residual light. S243: Set the proportion of the first cyan-green light band to be greater than or equal to the first threshold, the proportion of the first deep red light band to be greater than or equal to the second threshold, and the proportion of the first blue light residue to be less than or equal to the third threshold to obtain the proportion constraint parameters.

[0035] Specifically, the total luminous flux Φtotal = Φg + Φy + Φr + Φblue is calculated by linearly adding the green light flux Φg, yellow light flux Φy, red light flux Φr, and residual blue light flux Φblue. This total luminous flux serves as the total effective luminous intensity available for illumination output under this configuration. Using the total luminous flux as the denominator, dividing Φg by Φtotal yields the proportion of the first cyan-green light band, Pcyan = Φg / Φtotal, representing the coverage of the entire spectrum energy in the green light conversion section. Dividing Φr by Φtotal yields the proportion of the first deep red light band, Pred = Φr / Φtotal, reflecting the contribution ratio of the red fluorescent band in the illumination output. Dividing Φblue by Φtotal yields the proportion of the first residual blue light band, Rblue = Φblue / Φtotal, used to assess the proportion of blue light energy that is directly transmitted without being absorbed by the phosphor. This proportion is directly related to the blue light biosafety level. The three relative proportions are compared with preset spectral continuity and photobiological safety standards. The proportion of cyan light (Pcyan) should be greater than or equal to the first threshold (P1, e.g., 0.18) to ensure the integrity of the visually sensitive wavelength band. The proportion of deep red light (Pred) should be greater than or equal to the second threshold (P2, e.g., 0.22) to meet the compensation requirements for far-red light. The proportion of residual blue light (Rblue) should be less than or equal to the third threshold (P3, e.g., 0.25) to avoid the risk of blue light damage. If all three conditions are met, the set of proportion parameters is marked as a valid solution that meets the spectral proportion constraints. If any proportion deviates from the preset threshold, the next round of adjustment is initiated.

[0036] Figure 3 This is a graph showing the changes in spectral proportion parameters during the iterative adjustment of the formulation. Solid lines with dots indicate that the proportion of cyan-green light gradually increased from an initial 0.11 to 0.19 and stabilized above the first threshold of 0.18. Long dashed lines with squares indicate that the proportion of deep red light increased from 0.09 to 0.24 and stabilized above the second threshold of 0.22. Short dashed lines with triangles indicate that the proportion of residual blue light decreased from 0.42 to 0.21 and stabilized below the third threshold of 0.25. Horizontal dashed lines mark the threshold lines for the three formulation constraint parameters. The boxes illustrate the specific adjustment strategies for the 2nd and 4th iterations, namely increasing the proportion of green phosphor by 2-2% and the proportion of red phosphor by 3-4%. The convergence region marked by the dashed boxes indicates that after 5 iterations, all three spectral proportion parameters met the formulation constraint requirements, achieving the optimization goal of full-spectrum healthy lighting.

[0037] In one specific embodiment, the process of performing step S3 may specifically include the following steps: S31: Calculate the spectral proportion parameters based on the first mass proportion. The spectral proportion parameters include the proportion of the second cyan-green light band, the proportion of the second deep red light band, and the proportion of the second blue light residue. S32: Determine whether the proportion of the second cyan-green light band is less than the first threshold, whether the proportion of the second deep red light band is less than the second threshold, and whether the proportion of the second blue light residue is greater than the third threshold, and determine the type of phosphor that needs to be adjusted. S33: If the proportion of the second cyan-green light band is less than the first threshold, the proportion of green phosphor is increased by a preset first increment. If the proportion of the second deep red light band is less than the second threshold, the proportion of red phosphor is increased by a preset second increment. The sum of the first increment and the second increment is subtracted from the proportion of yellow phosphor to obtain the second proportion.

[0038] Specifically, the set first mass proportion values ​​wg, wy, and wr correspond to the mass proportions of green, yellow, and red phosphors, respectively. Combined with the initial spectral radiant flux Φ0 of the blue light-emitting diode, the absorption cross-sectional coefficients αg, αy, and αr of the three phosphors in the blue light band, and their quantum efficiencies ηg, ηy, and ηr, the green light flux Φg = Φ0 × wg × αg × ηg, the yellow light flux Φy = Φ0 × wy × αy × ηy, and the red light flux Φr = Φ0 × wr × αr × ηr are calculated. The blue light flux is then calculated. The residual flux Φblue = Φ0 × [1 – (wg × αg + wy × αy + wr × αr)] is then summed to obtain the total luminous flux Φtotal = Φg + Φy + Φr + Φblue. The residual fluxes of green, red, and blue light are divided by the total luminous flux to obtain the proportions of the second cyan-green band (Pcyan = Φg / Φtotal), the proportion of the second deep red band (Pred = Φr / Φtotal), and the proportion of the second blue residual band (Rblue = Φblue / Φtotal). These three normalized ratios are logically compared with set spectral thresholds P1, P2, and P3. If Pcyan is lower than P1 (e.g., 0.18), it indicates insufficient coverage of the cyan-green region in the visible spectrum by the green phosphor; if Pred is lower than P2 (e.g., 0.22), it indicates that the energy of the red fluorescent band does not meet the compensation requirements for deep red light; if Rblue is higher than P3 (e.g., 0.25), it indicates that excessive blue light residue poses a potential hazard to the human eye. The mass ratio is dynamically adjusted based on the comparison results. If Pcyan does not meet the standard, the mass ratio of green phosphor wg is increased by Δwg. If Pred does not meet the standard, the mass ratio of red phosphor wr is increased by Δwr. Under the premise of keeping the total mass ratio constant, the sum of Δwg and Δwr is subtracted from the mass ratio of yellow phosphor wy. That is, the new ratio is set as wg'=wg+Δwg, wr'=wr+Δwr, wy'=wy–(Δwg+Δwr), thus obtaining the second mass ratio.

[0039] Figure 5This diagram illustrates the down-conversion energy transfer of multi-band phosphors excited by blue light. The blue LED chip emits 450-460nm blue light, exciting three types of phosphor particles in the intermediate layer. The green phosphor is β-Sialon:Eu. 2+ After absorbing 450nm blue light, it emits 530nm green light (Stokes shift 80nm), using a yellow phosphor YAG:Ce. 3+ After absorbing 460nm blue light, it emits 560nm yellow light (Stokes shift 100nm), and the red phosphor K2SiF6:Mn is used. 4+ After absorbing 455nm blue light, it emits 630nm red light (Stokes shift 175nm). Solid arrows indicate the blue light excitation process, and dashed arrows indicate the downconversion emission process. The bottom composite spectrum shows the superposition of blue light residue with the green, yellow, and red emission peaks, achieving continuous coverage across the entire 380-780nm wavelength range. In this embodiment, the energy downconversion principle and the control of luminous flux distribution by the mass ratio demonstrate the physical mechanism by which this invention achieves full-spectrum healthy lighting through the synergistic effect of multi-band phosphors.

[0040] In this embodiment, after step S33, a luminous flux loss compensation calculation step is further included: The initial total luminous flux is calculated based on the first mass ratio; the green, yellow, red, and blue residual fluxes calculated based on the first mass ratio are added together to obtain the first total luminous flux; the additional blue light absorption is calculated based on the increased green phosphor mass ratio and red phosphor mass ratio in the second mass ratio; the increased green phosphor mass ratio is multiplied by the first absorption cross-section coefficient to obtain the additional green phosphor absorption contribution; the increased red phosphor mass ratio is multiplied by the third absorption cross-section coefficient to obtain the additional red phosphor absorption contribution; the two additional absorption contributions are added together to obtain the additional blue light absorption; the theoretical luminous flux loss value is calculated based on the additional blue light absorption and the first and third quantum efficiencies; the additional blue light absorption is then multiplied by the first quantum efficiency and the third quantum efficiency, respectively. The sub-efficiencies are multiplied and summed, and compared with the first total luminous flux to calculate the theoretical luminous flux loss rate. A luminous flux loss threshold is set, and it is determined whether the theoretical luminous flux loss rate exceeds the threshold. If it does, a luminous flux compensation coefficient is established, and the ratio of the luminous flux loss threshold to the theoretical luminous flux loss rate is used as the luminous flux compensation coefficient. The second mass ratio is corrected according to the luminous flux compensation coefficient. The mass ratio of green phosphor in the second mass ratio is multiplied by the luminous flux compensation coefficient, the mass ratio of yellow phosphor in the second mass ratio is multiplied by the luminous flux compensation coefficient, and the mass ratio of red phosphor in the second mass ratio is multiplied by the luminous flux compensation coefficient. The three corrected mass ratios are normalized so that their sum is 1, resulting in the third mass ratio after luminous flux balance. The third mass ratio is used as the final proportioning parameter and passed to step S4 for phosphor weighing.

[0041] In this embodiment, a spectral defect type identification and grading adjustment step is included between steps S32 and S33: The spectral defect type is determined based on the deviations of the second cyan-green band proportion from the first threshold, the second deep red band proportion from the second threshold, and the second blue residual proportion from the third threshold. If the second cyan-green band proportion is less than the first threshold and its deviation is greater than the deviation of the second deep red band proportion, it is determined to be a cyan-green dominant defect type. If the second deep red band proportion is less than the second threshold and its deviation is greater than the deviation of the second cyan-green band proportion, it is determined to be a deep red dominant defect type. If the deviations of the second cyan-green band proportion and the second deep red band proportion are equivalent, it is determined to be a full-spectrum synergistic defect type. A differentiated adjustment strategy for the phosphor ratio is determined based on the spectral defect type. For cyan-green dominant defect types, the preset first increment is set to 1.5 to 2 times the base increment, and the preset second increment is set to 0.5 to 1 times the base increment. For deep red dominant defect types, the preset second increment is set to 1.5 to 2 times the base increment, and the preset first increment is set to 0.5 to 1 times the base increment. For full-spectrum synergistic defect types, both the preset first and second increments are set to the base increment. The ratio adjustment is performed according to the differentiated adjustment strategy and continuously verified. The adjusted mass ratio is resubmitted into step S31 to calculate the new spectral ratio parameter. It is determined whether the new spectral ratio parameter meets the ratio constraint parameter. If it does not meet the constraint parameter, the spectral defect type determination and differentiated adjustment process is repeated until the ratio constraint parameter is met or the preset maximum number of iterations is reached to obtain the second mass ratio.

[0042] In one specific embodiment, step S33 includes: S331: If the proportion of the second cyan-green light band is less than the first threshold, the proportion of green phosphor mass is increased by a preset first increment; if the proportion of the second deep red light band is less than the second threshold, the proportion of red phosphor mass is increased by a preset second increment. S332: Add the first increment and the second increment to obtain the total adjustment; S332: Add the mass percentage of green phosphor to the corresponding first increment, add the mass percentage of red phosphor to the corresponding second increment, and subtract the total adjustment amount from the mass percentage of yellow phosphor to obtain the second mass percentage.

[0043] Specifically, when the proportion of the second cyan-green band (Pcyan) calculated by the luminous flux model is lower than a preset first threshold (P1, e.g., 0.18), the proportion of green phosphor (wg) is increased by a preset first increment (Δwg). This first increment is set to a fixed value in the system (e.g., 0.02 or 0.04) to enhance the proportion of green phosphor in the conversion path and increase green light flux output. Simultaneously, if the proportion of the second deep red band (Pred) is lower than a second threshold (P2, e.g., 0.22), the proportion of red phosphor (wr) is increased by another preset second increment (Δwr) to improve the energy coverage of the deep red light emission portion. These two increments represent local compensation operations for spectral continuity in different bands. The two increments (Δwg and Δwr) are linearly added to calculate the total adjustment (Δw = Δwg + Δwr). The total adjustment represents the mass proportion that needs to be freed up from other phosphor proportions in the entire formulation structure. While increasing the proportions of green and red phosphors, an equal amount of Δw is subtracted from the mass proportion of yellow phosphor, wy. This updates the mass proportions of green phosphor to wg' = wg + Δwg, red phosphor to wr' = wr + Δwr, and yellow phosphor to wy' = wy – Δw, forming a second mass proportion structure (wg', wy', wr'). If a proportion deviation still exists, the above increase / decrease process is repeated iteratively until all three band proportion parameters simultaneously meet the set threshold requirements.

[0044] In this embodiment, a ratio fine-tuning step based on color temperature shift prediction is also included between steps S3 and S4: The synthetic spectral distribution of the mixed phosphors is calculated according to the second mass ratio; the green light flux is multiplied by the normalized emission spectral function of the green phosphor, the yellow light flux by the normalized emission spectral function of the yellow phosphor, the red light flux by the normalized emission spectral function of the red phosphor, and the blue residual flux by the normalized spectral function of the blue chip, and then wavelength integration is performed to obtain the theoretical synthetic spectral distribution curve; the CIE1931 chromaticity coordinates are calculated based on the theoretical synthetic spectral distribution curve, and the results are obtained in 3... In the 80nm to 780nm wavelength range, tristimulus values ​​were integrated with the theoretically synthesized spectral distribution curve and the CIE standard chromaticity matching function to obtain the X, Y, and Z tristimulus values. X was divided by the sum of X, Y, and Z to obtain the chromaticity coordinate x-value, and Y was divided by the sum of X, Y, and Z to obtain the chromaticity coordinate y-value. Based on the chromaticity coordinate x-value and chromaticity coordinate y-value, the predicted correlated color temperature was calculated. The difference between the chromaticity coordinate x-value and 0.3320 was divided by the difference between the chromaticity coordinate y-value and 0.1858 to obtain the intermediate variable n. The cube of n was multiplied by 449, the square of n by 3525, and n was multiplied by 68. 23.3 is added to 5520.33 to obtain the relevant color temperature prediction value. The target color temperature range is set from the preset lower limit to the preset upper limit. It is then determined whether the relevant color temperature prediction value falls within the target color temperature range. If the predicted value is less than the preset lower limit, the color temperature is considered too cool and requires an increase in red light component. If the predicted value is greater than the preset upper limit, the color temperature is considered too warm and requires an increase in blue light residue or green light component. Fine-tuning parameters are calculated based on the color temperature offset direction and amount. If the color temperature is too cool, the difference between the relevant color temperature prediction value and the preset lower limit is calculated as the color temperature prediction value. The color temperature offset is divided by 1000 and multiplied by a preset fine-tuning coefficient to obtain the red phosphor increment coefficient. The red phosphor mass ratio in the second mass ratio is multiplied by 1 and the red phosphor increment coefficient is added. The yellow phosphor mass ratio in the second mass ratio is multiplied by 1 and half of the red phosphor increment coefficient is subtracted. The green phosphor mass ratio in the second mass ratio is multiplied by 1 and half of the red phosphor increment coefficient is subtracted. The fine-tuned mass ratios are normalized so that their sum is 1 to obtain the fourth mass ratio after color temperature optimization. The fourth mass ratio is then passed to step S4.

[0045] In one specific embodiment, the process of performing step S4 may specifically include the following steps: S41: Weigh out green phosphor, yellow phosphor and red phosphor according to the second mass ratio, and screen the phosphor particles that meet the preset requirements. S42: The screened phosphor particles are placed into a ball mill and dry-mixed at a preset speed to obtain mixed phosphor.

[0046] Specifically, based on the proportional relationship between the green phosphor mass percentage wg', the yellow phosphor mass percentage wy', and the red phosphor mass percentage wr' in the second mass ratio, the total mass mtotal required for mixing is determined. For example, if mtotal is set to 100g, then the mass of green phosphor is weighed as m1=wg'·mtotal, the mass of yellow phosphor is weighed as m2=wy'·mtotal, and the mass of red phosphor is weighed as m3=wr'·mtotal. After weighing, to improve the uniformity of blue light excitation and fluorescence conversion efficiency, the particle size distribution of the three phosphors was screened. A laser particle size analyzer was used to measure the D10, D50, and D90 particle size parameters of each phosphor, and the particle size span coefficient S=(D90–D10) / D50 was calculated as an evaluation index of particle distribution uniformity. Specifically, the median particle size D50 of the green phosphor was controlled between 9 and 11 micrometers with a span S not exceeding 0.75; the D50 of the yellow phosphor was controlled between 10 and 12 micrometers with a span not exceeding 0.80; and the D50 of the red phosphor was controlled between 8 and 10 micrometers with a span not exceeding 0.70. If the measured particle size parameter of a phosphor deviated from the requirements, materials with a larger D50 were reduced in size using air jet milling or wet grinding, while materials with a smaller D50 or a larger span were removed by centrifugal classification or sedimentation classification to eliminate fine powder or large particles, ensuring that the particle size of all particles added to the mixture was within the controlled range. After screening, the three qualified phosphor raw materials were separately fed into the mixing jar of a planetary ball mill. The ball mill jar was equipped with grinding balls of suitable material (such as zirconium oxide or stainless steel) to improve mixing and shearing efficiency. The ball mill speed was set to 300 rpm, and continuous mixing was performed for 15 to 20 minutes under normal pressure and drying conditions. Through mechanical impact and tumbling, phosphors with different specific gravities and surface morphologies were made to form a highly uniform distribution at the microscale. After mixing, particle size analysis or image analysis was used to evaluate the dispersion uniformity of the mixed powder. The coefficient of variation (CV) was required to be controlled within 15% to ensure a consistent spatial density distribution of the phosphor in the silicone system during encapsulation. This avoids localized luminescence imbalance or color drift caused by phosphor agglomeration or uneven distribution, resulting in a tri-color mixed phosphor that meets particle size specifications, precise proportions, and uniform mixing.

[0047] In this embodiment, step S41 further includes an excitation depth matching step based on particle size classification: The particle size distribution parameters of green, yellow, and red phosphors are measured using a laser particle size analyzer; the 10th percentile particle size D10, median particle size D50, and 90th percentile particle size D90 of each phosphor are extracted, and the particle size span value of each phosphor is calculated; the penetration depth of blue light in the three phosphor layers is calculated based on the first absorption cross-section coefficient, the second absorption cross-section coefficient, and the third absorption cross-section coefficient; the reciprocal of the product of the blue light wavelength and the first absorption cross-section coefficient and the phosphor packing density is used as the penetration depth of the green phosphor; the reciprocal of the product of the blue light wavelength and the second absorption cross-section coefficient and the phosphor packing density is used as the penetration depth of the yellow phosphor; and the reciprocal of the product of the blue light wavelength and the third absorption cross-section coefficient and the phosphor packing density is used as the penetration depth of the red phosphor; a matching relationship between particle size and excitation efficiency is established, and it is determined whether the median particle size D50 of each phosphor is greater than twice the corresponding penetration depth. If the green phosphor... If the median particle size D50 of the phosphor is greater than twice the penetration depth of the green phosphor, the phosphor is classified as Class I phosphor requiring further classification. Similarly, if the median particle size D50 of the yellow phosphor is greater than twice the penetration depth of the yellow phosphor, it is classified as Class I phosphor. The same applies to the red phosphor. Class I phosphors are then subjected to particle size classification. Particles larger than twice the corresponding penetration depth are removed using a sieving method, while particles with a particle size between 0.8 and 1.5 times the penetration depth are retained as excitation depth-matched particles. The effective absorption cross-section coefficient is recalculated based on the actual particle size distribution of each phosphor after classification. The ratio of the median particle size to the penetration depth after classification is used as a particle size correction factor. The original absorption cross-section coefficient is multiplied by the particle size correction factor to obtain the particle size-optimized effective absorption cross-section coefficient. The excitation depth-matched particles and the particle size-optimized effective absorption cross-section coefficient are then transferred to the mixing step.

[0048] In one specific embodiment, the process of performing step S5 may specifically include the following steps: S52: After mixing the mixed phosphor with the silicone matrix, the mixture is placed in a vacuum degassing machine and degassed under negative pressure to obtain a phosphor-silicone mixture. S53: Apply the phosphor-silicone mixture to the surface of a blue light-emitting diode chip at a preset dosage and then cure it at a preset temperature for a preset time to obtain a light-emitting diode device.

[0049] Specifically, the phosphor, homogenized and mixed in a ball mill, is added to a pre-prepared two-component addition-type silicone system at a preset mass ratio. Component A of the silicone system is polydimethylsiloxane containing vinyl functional groups, and component B is a hydrogen-containing siloxane crosslinking agent and a platinum catalyst. Components A and B are thoroughly mixed at a 1:1 mass ratio and immediately added to the phosphor system. Low-speed mechanical stirring is used for uniform dispersion, ensuring the phosphor particles form a three-dimensional dispersed network structure in the silicone matrix without agglomeration and with a low sedimentation rate. Immediately after mixing, the resulting composite is placed in a vacuum degassing machine and continuously degassed for 10 minutes under a negative pressure of -0.09 MPa. This gas expansion-rupture mechanism eliminates microbubbles introduced by stirring and pores formed due to surface tension within the material, ensuring the phosphor-silicone mixture has good flowability, uniformity, and light transmittance, forming a stable encapsulating colloid. The degassed phosphor-silicone mixture is loaded into a precision dispensing system. A micro-pump valve controls the precise dispensing of the mixture at a preset dosage (e.g., 0.02 mL) onto the surface of a blue light-emitting diode (LED) chip. The chip has a 1 mm × 1 mm rectangular structure, and its emitting surface must completely cover the phosphor adhesive layer to achieve full-spectrum blue light excitation. During dispensing, continuous and stable dispensing and uniform adhesive layer thickness are ensured, avoiding asymmetrical structures such as thin edges, thick centers, or material accumulation. Immediately after dispensing, the chip is placed on a pre-controlled thermosetting platform and held at 150°C for 60 minutes. This allows the addition-cure silicone system to undergo a cross-linking reaction, forming a dense elastomer. Simultaneously, the phosphor particles are encapsulated and fixed within the solid colloid, achieving structural curing and optical coupling between the phosphor conversion layer and the chip interface. This results in a full-spectrum healthy lighting LED device with stable colloidal composition, high spectral conversion efficiency, and strong encapsulation reliability.

[0050] The phosphor mixing method for the full-spectrum healthy lighting light-emitting diode in the embodiments of the present invention has been described above. The full-spectrum healthy lighting light-emitting diode in the embodiments of the present invention is described below. The full-spectrum healthy lighting light-emitting diode in the embodiments of the present invention is used to perform the phosphor mixing method for the full-spectrum healthy lighting light-emitting diode described above.

[0051] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0052] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0053] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for proportioning phosphors in a full-spectrum healthy lighting light-emitting diode, characterized in that, include: S1: Measure the spectral radiant flux and phosphor conversion parameters of the blue light-emitting diode chip; S2: Calculate the green light flux, yellow light flux, and red light flux based on the spectral radiant flux and the phosphor conversion parameters, and set the ratio constraint parameters; S3: Calculate the spectral proportion parameter based on the first mass proportion, and generate the second mass proportion according to the spectral proportion parameter and the ratio constraint parameter; S4: Weigh out green phosphor, yellow phosphor and red phosphor according to the second mass ratio and mix them to obtain mixed phosphor; S5: The mixed phosphor is mixed with the silicone substrate and then dotted onto the surface of the blue light-emitting diode chip and cured to obtain a light-emitting diode device.

2. The phosphor formulation method for a full-spectrum healthy lighting light-emitting diode according to claim 1, characterized in that, Step S1 includes: S11: Perform spectral measurement on the blue light-emitting diode chip under a preset driving current, record the spectral intensity data of the blue light band, and extract the spectral radiant flux. S12: Excitation spectra and quantum efficiency measurements are performed on green phosphor, yellow phosphor, and red phosphor in the blue light band to obtain phosphor conversion parameters, including the first absorption cross-sectional coefficient and first quantum efficiency of green phosphor, the second absorption cross-sectional coefficient and second quantum efficiency of yellow phosphor, and the third absorption cross-sectional coefficient and third quantum efficiency of red phosphor.

3. The phosphor formulation method for a full-spectrum healthy lighting light-emitting diode according to claim 2, characterized in that, Step S2 includes: S21: Multiply the spectral radiant flux by the mass ratio of green phosphor, the first absorption cross-sectional coefficient, and the first quantum efficiency to obtain the green light flux; S22: Multiply the spectral radiant flux by the mass ratio of the yellow phosphor, the second absorption cross-sectional coefficient, and the second quantum efficiency to obtain the yellow light flux; S23: Multiply the spectral radiant flux by the mass ratio of the red phosphor, the third absorption cross-section coefficient, and the third quantum efficiency to obtain the red light flux; S24: Calculate the proportion of cyan-green light band, the proportion of deep red light band, and the proportion of blue residual light based on the green light flux, the yellow light flux, and the red light flux. Set the proportion of cyan-green light band to be greater than or equal to a first threshold, the proportion of deep red light band to be greater than or equal to a second threshold, and the proportion of blue residual light to be less than or equal to a third threshold to obtain the ratio constraint parameters.

4. The phosphor formulation method for a full-spectrum healthy lighting light-emitting diode according to claim 3, characterized in that, Step S21 includes: S211: Multiply the spectral radiant flux by the mass ratio of the green phosphor and the first absorption cross-sectional coefficient to obtain the blue light energy absorbed by the green phosphor; S212: Multiply the blue light energy absorbed by the green phosphor by the first quantum efficiency to obtain the green light flux.

5. The phosphor formulation method for a full-spectrum healthy lighting light-emitting diode according to claim 3, characterized in that, Step S24 includes: S241: Add the green light flux, the yellow light flux, the red light flux, and the blue residual light flux to obtain the total light flux; S242: Divide the green light flux by the total light flux to obtain the first cyan-green light band ratio; divide the red light flux by the total light flux to obtain the first deep red light band ratio; divide the blue light residual flux by the total light flux to obtain the first blue light residual ratio. S243: Set the proportion of the first cyan-green light band to be greater than or equal to the first threshold, the proportion of the first deep red light band to be greater than or equal to the second threshold, and the proportion of the first blue light residue to be less than or equal to the third threshold to obtain the ratio constraint parameters.

6. The phosphor formulation method for a full-spectrum healthy lighting light-emitting diode according to claim 5, characterized in that, Step S3 includes: S31: Calculate the spectral proportion parameters based on the first mass proportion, the spectral proportion parameters including the proportion of the second cyan-green light band, the proportion of the second deep red light band, and the proportion of the second blue light residue; S32: Determine whether the proportion of the second cyan-green light band is less than the first threshold, whether the proportion of the second deep red light band is less than the second threshold, and whether the proportion of the second blue light residue is greater than the third threshold, and determine the type of phosphor that needs to be adjusted; S33: If the proportion of the second cyan-green light band is less than the first threshold, then the mass proportion of the green phosphor is increased by a preset first increment. If the proportion of the second deep red light band is less than the second threshold, then the mass proportion of the red phosphor is increased by a preset second increment. The sum of the first increment and the second increment is subtracted from the mass proportion of the yellow phosphor to obtain the second mass proportion.

7. The phosphor formulation method for a full-spectrum healthy lighting light-emitting diode according to claim 6, characterized in that, Step S33 includes: S331: If the proportion of the second cyan-green light band is less than the first threshold, then the mass proportion of the green phosphor is increased by a preset first increment; if the proportion of the second deep red light band is less than the second threshold, then the mass proportion of the red phosphor is increased by a preset second increment. S332: Add the first increment and the second increment to obtain the total adjustment; S332: Add the mass percentage of green phosphor to the corresponding first increment, add the mass percentage of red phosphor to the corresponding second increment, and subtract the total adjustment amount from the mass percentage of yellow phosphor to obtain the second mass percentage.

8. The phosphor formulation method for a full-spectrum healthy lighting light-emitting diode according to claim 1, characterized in that, Step S4 includes: S41: Weigh the green phosphor, the yellow phosphor, and the red phosphor according to the second mass ratio, and screen the phosphor particles that meet the preset requirements; S42: The screened phosphor particles are placed into a ball mill and dry-mixed at a preset speed to obtain mixed phosphor.

9. The phosphor formulation method for a full-spectrum healthy lighting light-emitting diode according to claim 8, characterized in that, Step S5 includes: S52: The mixed phosphor and the silicone matrix are mixed and then placed in a vacuum degassing machine for degassing under negative pressure to obtain a phosphor-silicone mixture. S53: The phosphor-silicone mixture is applied to the surface of the blue light-emitting diode chip at a preset dosage and then cured at a preset temperature for a preset time to obtain a light-emitting diode device.

10. A full-spectrum healthy lighting light-emitting diode, characterized in that, A phosphor formulation method for executing a full-spectrum healthy lighting light-emitting diode as described in any one of claims 1-9.

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