Light-emitting Diode Chip Research Articles

Modification of the n-Surface Profile of AlGaInN LEDs by Changing the Gas-Mixture Composition During Reactive Ion Etching

The kind of profile produced during the reactive ion etching of AlGaInN light-emitting-diode (LED) heterostructures on the surface that became free after removal of the growth substrate is studied in relation to the composition of the gas mixture used in the etching process. It is shown that using a mixture composed of Cl2 and Ar, taken in a 3:2 ratio in terms of flow rates, leads to the thinnest profile, whereas a 2 : 1 gas mixture of BCl3 and Ar provides the largest structural elements. To study the effect of the kind of profile on the quantum efficiency (QE), flip-chip LEDs are fabricated on a silicon substrate. The LEDs are etched in different modes after the growth substrate is removed. Etching in the Cl2:BCl3:Ar mixture with a flow ratio of 6:10:11, which leads to intermediate sizes of the etching profile elements, is optimal for obtaining maximum light extraction from a LED chip at a wavelength of 460 nm. The variation of the kind of profile with the gas-mixture composition suggests that the profile parameters can be tuned to the wavelength used. An analysis of how the QE of LED chips depends on the etching duration in the three-component mixture under consideration results in that the optimum etching duration is estimated to be ~30 min. The results of the study can also be of use in the search for conditions minimizing the reflection of incident light by a chip, e.g., for photodetectors.

Preparation, crystal structure, and photoluminescence properties of high-brightness red-emitting Ca2LuNbO6:Eu3+ double-perovskite phosphors for high-CRI warm-white LEDs

Near-ultraviolet-excited efficient red phosphors are important for fabricating warm-white light-emitting diodes (LEDs) with high color rendering index. Herein, we demonstrated the preparation of novel highly efficient Eu3+ ions-activated Ca2LuNbO6 (CLN) double-perovskite phosphors. These phosphors were prepared by the high-temperature solid-state reaction method and they were characterized by powder X-ray diffraction, Rietveld refinement, excitation and emission spectra, decay lifetimes, internal quantum efficiency, and temperature-dependent emission spectra. The as-prepared phosphors can be efficiently excited by 396 nm near-ultraviolet light and generated bright red luminescence around 591, 616, 656 and 703 nm corresponding to the 5D0→7FJ (J = 1–4) transitions of Eu3+ ions. The optimal doping concentration of CLN:xEu3+ (x = 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, and 0.8) phosphors was x = 0.4, and the optimal CLN:0.4Eu3+ sample exhibited high-color-purity (96.4%) red emission with internal quantum efficiency as great as 66%. The thermal-quenching resistance was evaluated by measuring their temperature-dependent emission intensities, while the emission intensity at 150 °C was about 65% of that at room temperature. Finally, a warm white LED lamp was made by using a 395 nm LED chip together with a phosphor blend of commercial blue phosphor BaMgAl10O17:Eu2+ and commercial green phosphor (Ba,Sr)2SiO4:Eu2+ and newly developed red phosphor CLN:0.4Eu3+, which gave bright high-quality white light with Commission Internationale de l’Eclairage (CIE) chromaticity coordinates of (0.3878, 0.3725), a correlated color temperature of 3769 K, and a color rendering index of 94 when the driven current was 20 mA. These investigation results clearly revealed the promising application potential of CLN:Eu3+ red phosphors in high-color-quality solid-state white lighting.

Filling the cyan gap toward full-visible-spectrum LED lighting with Ca2LaHf2Al3O12:Ce3+ broadband green phosphor

In this paper, a new garnet-based Ce3+-activated Ca2LaHf2Al3O12 (CLHAO) green phosphor with broadband emissions covering the cyan and green regions was successfully designed. The crystal structure and photoluminescence characteristics of the as-prepared sample were investigated in detail. Under the excitation of 408 nm, the optimal CLHAO:0.05Ce3+ green phosphors exhibited a broad emission band in the range of 450–700 nm with a peak at 515 nm. Impressively, the full width at half-maximum (FWHM) of this sample was determined to be about 116 nm, which was much broader than that of commercial (Ba,Sr)2SiO4:Eu2+ green phosphors (FWHM = 67 nm). The internal quantum efficiency of CLHAO:0.05Ce3+ green phosphors was measured to be 46.5%. Finally, by using a 400 nm LED chip and the commercial CaAlSiN3:Eu2+ red phosphors, the as-prepared CLHAO:0.05Ce3+ green phosphors, as well as the BAM:Eu2+ blue phosphors, a package of white light-emitting diode (LED) device was fabricated. Interestingly, under 60 mA current, the white LED device displayed a smooth emission spectrum, without a spectrum cavity in cyan region. And thus the resulting warm white light possessed a high CRI value (Ra) of 92.0, which was greatly better than that of another white LED device fabricated by using commercial (Ba,Sr)2SiO4:Eu2+ green phosphors as color converter (Ra = 80.6). We anticipate that the work presented here may open up new insights for finding high-performance color-converting phosphors for high-CRI solid-state lighting devices.

Broadband near-infrared emitting from Li1.6Zn1.6Sn2.8O8:Cr3+ phosphor by two-site occupation and Al3+ cationic regulation

Broadband sources of near-infrared (NIR) radiation have garnered considerable attention in medical applications and non-destructive analysis. In this work, we have synthesized a lithium zinc stannate phosphor Li1.6Zn1.6Sn2.8O8:Cr3+ (LZSO:Cr) for broadband NIR light sources. The LZSO:Cr phosphor exhibited broadband excitation band matches exceptionally well with the emission of commercial 450-nm blue light-emitting diode (LED) chips. As expected, the broadband emission of infrared radiation from 650 nm to 1200 nm was realized due to the unique crystal field environment, where Cr3+ ions were substituted in two distorted octahedral sites. The broad emission spectrum exhibited peaks around 830 nm and 930 nm with a full width at half maximum (FWHM) of ~190 nm and internal quantum efficiency of 53%. The FWHM could be tuned to ~220 nm by co-doping with Al3+ ions because of the crystal splitting. The luminescence properties including excitation, emission, decay time, and their relationship between the lattice crystal properties have also been investigated. A phosphor-converted LED (pc-LED) was packaged by combining the phosphor with a 450-nm blue LED chip, which proves the feasibility of our design strategy for broadband NIR light sources.

Investigation of Thermal Effect on Reliability and Chromaticity Shift in QD-LEDs Displays

In this work, thermal effect on reliability and chromaticity shift in quantum dots (QDs)-based light emitting diodes (LEDs) are investigated by long term lifetime test and IR thermal image. The results have suggested that the heat power generation during luminescence conversion process play a key role in the compatibility between QD and encapsulation resin, which is correlated to the blue luminescence intensity generated from LED chip and the QD luminescence intensity converted by QDs. The ligands detachment of QD at luminescence conversion process results in poor reliability of QDs and influence on the thermal load ability of encapsulation resin, whereas the condition of QD should be a dominant factor. It was also found that QD with thicker shell could prevented heat power generation since higher conversion efficiency and better stability, shown the better reliability of QD-LEDs and less chromaticity shift.

Effects of size on the electrical and optical properties of InGaN-based red light-emitting diodes

We investigated the effects of size on electrical and optical properties of InGaN-based red light-emitting diodes (LEDs) by designing rectangular chips with different mesa lengths. Larger chips exhibited lower forward voltages because of their lower series resistances. A larger chip helped to realize a longer emission wavelength, narrower full-width at half maximum, and higher external quantum efficiency. However, temperature-dependent electroluminescence measurements indicated that larger chips are detrimental to applications where high temperature tolerance is required. In contrast, a smaller red LED chip achieved a high characteristic temperature of 399 K and a small redshift tendency of 0.066 nm K−1, thus showing potential for temperature tolerant lighting applications.

Heat dissipation and electrical conduction of an LED by using a microfluidic channel with a graphene solution

Currently, electronic product development trends include design of thin, low-weight, multifunctional, and highly integrated devices. Electronic chips tend to feature high-speed, high-power, and high-concentration properties, and the amount of heat per unit volume increases rapidly. If the total volume is reduced, poor heat dissipation results in product failure. This study proposed that solid conductors could be replaced by a microchannel and graphene solution, with the graphene solution supplying energy and dissipating heat in a light-emitting diode (LED). The temperature at the bottom of the LED chip with the graphene solution conductor was considerably lower than that of the chip with the solid conductor. The difference between the optical power of the LED with the solid and graphene solution conductors was small. Additionally, the optical power of the LED with the graphene solution was considerably higher than that of the LED with the salt electrolyte conductor, and the temperature difference between the bottom of the LED chip with the graphene solution and that of the LED chip with the salt electrolyte was very small. The graphene solution was a suitable conductor for the LED; hence, it can facilitate new designs of LEDs in the future.

Rapid Anneal-Free Welding of Cu Nanowires Network by Ultraviolet Light Irradiation for Transparent Electrodes in Optoelectronic Applications

Abstract We demonstrate a novel ultraviolet (UV) light irradiation strategy to rapidly weld Cu nanowires (NWs) network and remove the organic residues for transparent electrodes. Shortly irradiated by UV light source, the Cu NWs could achieve junction welding in the absence of any thermal annealing process. This Cu NWs network shows high optoelectronic performance (39 Ω/sq at 90% transmittance at 550 nm) and outstanding flexibility under bending and twisting. Completely transparent light-emitting diode (LED) chips array was fabricated and has been lighted with bright top-surface emission. This method could provide a fast and convenient way to fabricate Cu NWs transparent electrodes onto various optoelectronic products.

Effects of light intensity on mating of the black soldier fly (Hermetia illucens, Diptera: Stratiomyidae)

The irradiance (W/m2) of light to which groups of black soldier fly adults were exposed in screen cages was manipulated by varying the distance between the cages and a 100 W, white light-emitting diode (LED) chip on a 14L:10D photoperiod. After combining the sexes at the beginning of a light period (photophase), the mating status of all individuals was noted every 10 min for two consecutive photophases. Of all matings, 92% occurred during the first photophase. Mating pairs were nearly motionless and the duration of 93% of couplings was ≥20 min, so essentially all matings were observed. Cumulative probability of mating increased from an estimated 23% at an irradiance of 0.92 W/m2 to 70% at 431 W/m2. Over the same range of irradiances, average time of mating initiation decreased from an estimated 6.4 h to 3.4 h post photophase initiation so that the percentage of matings initiated 15:00 or later decreased from 50 to 0%. Consequently, the occurrence of matings more than 7 hours after photophase initiation was associated with reduced lifetime probability of mating. Peaks in the flux spectrum of the LED at 440 (indigo/blue) and 540 nm (green) coincided with published measurements of the wavelengths at which two of the classes of photoreceptors in the retina of the black soldier fly are maximally sensitive. This study suggests that mating success of reared black soldier fly can be dramatically increased by exposing the adults to light that is particularly rich in wavelengths near 440 and/or 540 nm and has an irradiance that is an appreciable fraction of the intensity of full sunlight.

Optimization of a green solid-state fan for electronics cooling applications

Miniaturization and high integration are two important factors hindering the further development of electronic devices. The generated heat flux has been increasing, thus requiring efficient cooling systems. The corona wind cooling technology has significant advantages and is likely a new effective solution for cooling electronics. A high-performance solid-state fan (SSF) based on corona discharge was designed and optimized. Carbon nanotubes and catalysts are used to modify the SSF in order to reduce ozone generation and cool a high power light-emitting diode (LED) chip. The experimental results indicate that the needle electrode arrangement, discharge polarity, temperature and relative humidity have a significant effect on the performance of the SSF. The positive corona, high environmental temperature and low relative humidity are beneficial to the original SSF. The modified SSF decreased the initiation voltage by half, increased the velocity by 13%, and reduced ozone production by more than 90%. The greener SSF showed better working durability and cooling performance, which reduced the case temperature by another 6 ℃ compared to the original one.

Fully convolutional networks for chip-wise defect detection employing photoluminescence images

Efficient quality control is inevitable in the manufacturing of light-emitting diodes (LEDs). Because defective LED chips may be traced back to different causes, a time and cost-intensive electrical and optical contact measurement is employed. Fast photoluminescence measurements, on the other hand, are commonly used to detect wafer separation damages but also hold the potential to enable an efficient detection of all kinds of defective LED chips. On a photoluminescence image, every pixel corresponds to an LED chip’s brightness after photoexcitation, revealing performance information. But due to unevenly distributed brightness values and varying defect patterns, photoluminescence images are not yet employed for a comprehensive defect detection. In this work, we show that fully convolutional networks can be used for chip-wise defect detection, trained on a small data-set of photoluminescence images. Pixel-wise labels allow us to classify each and every chip as defective or not. Being measurement-based, labels are easy to procure and our experiments show that existing discrepancies between training images and labels do not hinder network training. Using weighted loss calculation, we were able to equalize our highly unbalanced class categories. Due to the consistent use of skip connections and residual shortcuts, our network is able to predict a variety of structures, from extensive defect clusters up to single defective LED chips.

Room-temperature one-pot synthesis of highly stable SiO2-coated Mn-doped all-inorganic perovskite CsPb0.7Mn0.3Br0.75Cl2.25 quantum dots for bright white light-emitting diodes

In this paper, we report a simple one-pot strategy to synthesize highly stable SiO2-coated orange-yellow CsPb0.7Mn0.3Br0.75Cl2.25 quantum dots with strong orange-yellow photoluminescence. The microstructure characterization indicates that the CsPb0.7Mn0.3Br0.75Cl2.25 quantum dots were effectively encapsulated by the SiO2. The SiO2-coated CsPb0.7Mn0.3Br0.75Cl2.25 quantum dots show higher humidity stability and thermal stability than the CsPb0.7Mn0.3Br0.75Cl2.25 quantum dots without SiO2 coating. The white light-emitting diodes (WLEDs) were obtained by coating orange-yellow CsPb0.7Mn0.3Br0.75Cl2.25@SiO2 and blue CsPbBrCl2@SiO2 quantum dots on the ultraviolet gallium nitride light-emitting diode chip. The as-prepared white light-emitting diodes show bright white light emission with a color coordinate of (0.3347, 0.2825), color rendering index of 82 and correlated color temperature of 5329 K. The results provide a simple method to fabricate stable orange-yellow luminescent material for white light-emitting diodes.

Exciton photoluminescence of CsPbBr3@SiO2 quantum dots and its application as a phosphor material in light-emitting devices

In this report, we mainly investigate the optical property differences between CsPbBr3@SiO2 quantum dots (QDs) and CsPbBr3 QDs. The photoluminescence demonstrates that CsPbBr3@SiO2 QDs and CsPbBr3 QDs have similar exciton binding energy. Both CsPbBr3 and CsPbBr3@SiO2 QDs present optical bandgaps and photoluminescence (PL) linewidth broadening as the temperature increases from 10 K to room temperature, which is attributed to the thermal expansion and electron-phonon coupling. The fitting results show that CsPbBr3 and CsPbBr3@SiO2 QDs have the similar bandgap thermal expansion coefficient, but the CsPbBr3@SiO2 QDs have weaker electron-phonon interaction. Temperature-dependent time-resolved photoluminescence (TRPL) demonstrates that the PL lifetime increases with the temperature and CsPbBr3@SiO2 QDs have longer PL lifetime than CsPbBr3 QDs after 110 K. In addition, the CsPbBr3@SiO2 QDs integrated on the blue light-emitting diode chip as green phosphor material show better thermal stability in ambient air.

Orange-red-emitting CaTi4(PO4)6:Eu3+ phosphor for white LEDs: synthesis and luminescence properties

CaTi4(PO4)6:xEu3+ phosphors are successfully synthesized under air condition by high-temperature solid-state method. The crystal structure, morphology, energy spectrum, atomic percentage, elemental mapping, and luminescence properties are investigated, respectively. Monitored at 594 nm, the excitation spectral bands of CaTi4(PO4)6:Eu3+ phosphor in the range of 210–550 nm are assigned to the O2−–Eu3+ charge transfer band (CTB) and the 7F0 → 5H3, 5L7, 5L6, 5D1, 5D2, 5D3, and 5D4 transitions of Eu3+ ion. With excitation at 394 nm, CaTi4(PO4)6:Eu3+ phosphor emits orange-red light with the chromaticity coordinates (0.548, 452), and the emission spectral bands in the region from 575 to 720 nm are attributed to the 5D0 → 7F1, 7F2, 7F3, and 7F4 transitions of Eu3+ ion. The optimal doping concentration of Eu3+ ion is ~ 8 mol%. The lifetime of CaTi4(PO4)6:Eu3+ phosphors decreases from 1.87 to 0.97 ms with increasing Eu3+ concentrations from 1 to 10 mol%. CaTi4(PO4)6:Eu3+ phosphor has a good thermal stability. The experimental results indicate that CaTi4(PO4)6:Eu3+ phosphor has an application prospect in white light-emitting diodes (LEDs) based on the near ultraviolet (~ 394 nm) LED chip.

Thermal Assessment of Laminar Flow Liquid Cooling Blocks for LED Circuit Boards Used in Automotive Headlight Assemblies

This research work presents a comparative thermal performance assessment of the laminar flow cooling blocks produced for automotive headlight assembly using a high power Light Emitting Diode (LED) chip. A three-dimensional numerical model with conjugate heat transfer in solid and fluid domains was used. Laminar flow was considered in the present analysis. The validation of the numerical model was realized by using the measured data from the test rig. It was observed that substantial temperature variations were occurred around the LED chip owing to volumetric heat generation. The cooling board with lower height performs better thermal performance but higher pressure drop for the same mass flow rates. The cooling board with the finned cover plate performs better thermal performance but results in an increased pressure drop for the same mass flow rates. Increasing the power of the LED results in higher temperature values for the same mass flow rates. The junction temperature is highly dependent on the mass flow rates and LED power. It can be controlled by means of the mass flow rate of the coolant fluid. New Nusselt number correlations are proposed for laminar flow mini-channel liquid cooling block applications.

Fabrication of flexible AlGaInP LED

Flexible light-emitting diodes (LEDs) are highly desired for wearable devices, flexible displays, robotics, biomedicine, etc. Traditionally, the transfer process of an ultrathin wafer of about 10–30 μm to a flexible substrate is utilized. However, the yield is low, and it is not applicable to thick GaN LED chips with a 100 μm sapphire substrate. In this paper, transferable LED chips utilized the mature LED manufacture technique are developed, which possesses the advantage of high yield. The flexible LED array demonstrates good electrical and optical performance.

Effects of Ti4+- and W6+-substitution on photoluminescence properties of Sr2GdSbO6:Mn4+ phosphor for plant cultivation

A novel double perovskite Ti4+ and W6+ modified Sr2GdSbO6 (SGSO):Mn4+ far-red phosphor was prepared by traditional solid state reaction method. The samples were characterized by powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), photoluminescence spectra (PL), decay life, temperature-dependent emission spectra and internal quantum efficiency (IQE). Due to the 2E→4A2 transition of Mn4+ ions, the emission band centered at 667 nm was observed in the range of 600–780 nm, which matched the absorption spectra required for plant growth. The excitation spectra consist of four excitation bands, peaking at 276, 305, 358 and 506 nm in the range of 220–600 nm, respectively, which indicates that SGSO:Mn4+ phosphors can be excited by ultraviolet, near-ultraviolet and blue light emitting diode (LED) chips. The optimum doping concentration of Mn4+ is determined to 0.4 mol% and the concentration quenching mechanism is the dipole-quadrupole interaction of Mn4+ activator. The effect of co-doping Ti4+ and W6+ ions on the luminescent properties of SGSO:Mn4+ was studied. The PL intensity of SGSO:0.004Mn4+, 0.004Ti4+ and SGSO:0.004Mn4+, 0.004 W6+ are 1.65 and 2.07 times than that of SGSO:0.004Mn4+ phosphor. Impressively, all samples possess excellent thermal stability (I423K/I298K>70%). The results illustrate that Ti4+ and W6+ can significantly improve the luminescent properties and thermal stability of SGSO:Mn4+. Finally, a kind of LED device was fabricated by combining 365 nm ultraviolet LED chip with far-red light emitting SGSO:0.004Mn4+, 0.004 W6+ phosphors and BaMgAl10O17:Eu2+ blue phosphor. Because the emission band of SGSO:0.004Mn4+, 0.004 W6+ matches well with the absorption band of plant pigment PR, under the excitation of near ultraviolet (UV) to blue light, SGSO:0.004Mn4+, 0.004 W6+ phosphors have potential application prospects in indoor plant cultivation.

Novel highly luminescent double-perovskite Ca2GdSbO6:Eu3+ red phosphors with high color purity for white LEDs: Synthesis, crystal structure, and photoluminescence properties

High-efficiency red-emitting phosphors are required to fabricate high-performance white light-emitting diodes (LEDs). Herein, the novel highly efficient Eu3+-activated Ca2GdSbO6 double-perovskite red phosphors with good thermal stability toward warm-white LEDs were reported. A series of Ca2Gd(1-x)EuxSbO6 red phosphors with different Eu3+ doping concentrations (x = 0.2, 0.3, 0.4, 0.5, 0.6, 0.7 and 0.8) were synthesized by using high-temperature solid-state reaction method. Under the excitation of 396 nm near-ultraviolet light, these Ca2Gd(1-x)EuxSbO6 phosphors showed intense red emissions peaking at 612 nm due to the 5D0→7F2 transition of Eu3+ ions. The strongest luminescence intensity reached when Eu3+ doping concentration was x = 0.5, and the critical distance between Eu3+ activators was calculated to be 7.97 Å. The concentration quenching mechanism was due to the dipole-dipole interaction of Eu3+ ions. The CIE color coordinates of the optimal Ca2Gd0.5Eu0.5SbO6 phosphors were determined to be (0.6629, 0.3367), and the corresponding color purity reached about 94.9%. Importantly, the Ca2Gd0.5Eu0.5SbO6 phosphors revealed outstanding internal quantum efficiency of 73% and good thermal stability. The emission intensity of Ca2Gd0.5Eu0.5SbO6 phosphors at 423 K still remained about 73% of its initial value at 303 K. Finally, a prototype white LED device was fabricated by coating the phosphor blend of commercial blue-emitting BaMgAl10O17:Eu2+, green-emitting (Ba, Sr)2SiO4:Eu2+ and our as-prepared red-emitting Ca2Gd0.5Eu0.5SbO6 on a 395 nm LED chip. Under 20 mA driven current, the device showed bright warm-white light with CIE color coordinates of (0.3888, 0.3943), correlated color temperature of 3911 K, and color rendering index of 88.4. The results demonstrated that the developed novel red-emitting Ca2Gd0.5Eu0.5SbO6 phosphors could be used as potential color converters in white LEDs.

Red-emitting YAG: Ce, Mn transparent ceramics for warm WLEDs application

A series of YAG:Ce,Mn transparent ceramics were prepared via a solid-state reaction-vacuum sintering method. The effects of various Mn2+–Si4+ pair doping levels on the structure, transmittance, and luminescence properties were systematically investigated. These transparent ceramics have average grain sizes of 10–16 μm, clean grain boundaries, and excellent transmittance up to 83.4% at 800 nm. Under the excitation of 460 nm, three obvious emission peaks appear at 533, 590, and 745 nm, which can be assigned to the transition 5d→4f of Ce 3+ and 4T1→6A1 of Mn2+. Thus, the Mn2+–Si4+ pairs can effectively modulate the emission spectrum by compensating broad orange-red and red spectrum component to yield high quality warm white light. After the optimized YAG:Ce,Mn transparent ceramic packaged with blue light-emitting diode (LED) chips, correlated color temperature (CCT) as low as 3723 K and luminous efficiency (LE) as high as 96.54 lm/W were achieved, implying a very promising candidate for application in white light-emitting diodes (WLEDs) industry.

Machine-Learning Assisted Prediction of Spectral Power Distribution for Full-Spectrum White Light-Emitting Diode

The full-spectrum white light-emitting diode (LED) emits light with a broad wavelength range by mixing all lights from multiple LED chips and phosphors. Thus, it has great potentials to be used in healthy lighting, high resolution displays, plant lighting with higher color rendering index close to sunlight and higher color fidelity index. The spectral power distribution (SPD) of light source, representing its light quality, is always dynamically controlled by complex electrical and thermal loadings when the light source operates under usage conditions. Therefore, a dynamic prediction of SPD for the full-spectrum white LED has become a hot but challenging research topic in the high quality lighting design and application. This paper proposes a dynamic SPD prediction method for the full-spectrum white LED by integrating the SPD decomposition approach with the artificial neural network (ANN) based machine learning method. Firstly, the continuous SPDs of a full-spectrum white LED driven by an electrical-thermal loading matrix are discretized by the multi-peak fitting with Gaussian model as the relevant spectral characteristic parameters. Then, the Back Propagation (BP) and Genetic Algorithm-Back Propagation (GA-BP) NNs are proposed to predict the spectral characteristic parameters of LEDs operated under any usage conditions. Finally, the dynamically predicted spectral characteristic parameters are used to reconstruct the SPDs. The results show that: (1) The spectral characteristic parameters obtained by fitting with the Gaussian model can be used to represent the emission lights from multiple chips and phosphors in a full-spectrum white LED; (2) The prediction errors of both BP NN and GA-BP NN can be controlled at low level, that is to say, our proposed method can achieve a highly accurate SPD dynamic prediction for the full-spectrum white LED when it operates under different operation mission profiles.