As implied in the title, the triple-layer remote phosphor (TRP), constructed with the yellow YAG:Ce3+ layer at the bottom, the red CaMgSi2O6:Eu2+,Mn2+ phosphor layer on the top, and the green Ba2Li2Si2O7:Sn2+,Mn2+ phosphor layer between these two layers, is suggested in this paper to improve the color and luminescence of white LEDs (WLEDs). In order to control the red light for the purpose of increasing the color rendering index (CRI), it is suggested that the red CaMgSi2O6:Eu2+,Mn2+ phosphor should be applied in the TRP structure. Simultaneously, the structure uses the green Ba2Li2Si2O7:Sn2+,Mn2+ phosphor layer to control the green light, which increases the luminous efficacy (LE) of WLEDs. In addition, when the concentration of these two phosphors increases, the yellow YAG:Ce3+ concentration must be reduced to keep the average correlated color temperatures (ACCTs) stable at 6000 K to 8500 K. Besides, appropriate adjusting of CRI, LE, and color quality scale (CQS) is also analyzed by modifying the concentration of the green phosphor and red phosphor. The results show that the CRI can get better values if CaMgSi2O6:Eu2+,Mn2+ concentration is higher. In contrast, the CRI decreases dramatically when the concentration of Ba2Li2Si2O7:Sn2+,Mn2+ increases. Meanwhile, CQS can be significantly increased in the range of 10 % to 14 % CaMgSi2O6:Eu2+,Mn2+, regardless of the concentration of Ba2Li2Si2O7:Sn2+,Mn2+. In particular, along with the improvement of CRI and CQS, LE can also be increased by more than 40 % by reducing the scattered light and adding the green light. Obtained results are a valuable reference for manufacturers for improving WLEDs color and luminescence quality to produce a broader range of WLEDs with better quality fulfilling social needs.

<span>The white light-emitting diode (WLED) has been the most advance lighting method currently, however, the fabrication process of this configuration still has drawbacks which negatively affect its color quality. This research was conducted to provide a method for WLED’s lighting output enhancement. Since CaCO₃ particles are excellent for thermal stability enhancement, especially when being combined with an adhesive substance, we decided to integrate CO₃ particles into resin matrix such as melamine formaldehyde (MF) and investigate their influences on the optical properties, including color uniformity and lumen output, of the WLED. The results showed that CaCO3 and MF resin are beneficial to the light scattering efficiency, which results in higher luminous flux and chromatic quality for WLED packages. In addition to that, the appropriate amounts of MF resin and CaCO₃ for reaching the best lumen efficiency and color quality are figured out at 1% and 10%, respectively. Moreover, another advantage of using MF resin and CaCO₃ for fabricating WLEDs is cost effectiveness. Hence, it has turned out that CaCO₃ and MF resins can be potential materials for next high-quality WLED generations.</span>

<span>In the effort of improving the performance of white light LEDs devices (WLEDs), the SiO₂ nano-particles were applied and have shown a significant impact on the optical properties. Specifically, the light output of the lighting devices is enhanced when a mixture of SiO₂ particles and silicone gel is diffused on the encapsulation layer surface. This enhancement is the result of light scattering from SiO₂ that strengthens the emitted blue light at further angles and reduces the color discrepancy. The evidence is that CCT deviation in SiO₂-doped structure decline from 1000 K to 420 K in -70° to 70°. In addition, the SiO₂ with refractive index in between the phosphor material and outside environment allows light to be emitted outward more effectively. This lighting enhancement of SiO₂-doped structure increases the lumen output by 2.25% at 120 mA power source in comparison to structure without SiO₂. These experimental outcomes suggest that SiO₂ is an effective material to add in WLEDs structure for better lighting efficiency.</span>

BaAl1.4Si0.6O3.4N0.6:Eu 2+ exhibiting broad excitation and emission bands with intense green emission centred at 510 nm is applied to produce high-performance white-light-emitting diodes (WLEDs). The preparation of the green phosphor utilizes NaNO3 molten salt to attain the purity phase and enhanced luminescence strength boosting the crystalline growth. The influences of BaAl1.4Si0.6O3.4N0.6:Eu 2+ on the lighting intensity and color adequacy are investigated at three correlated color temperatures (CCTs) of 3000 K, 4000 K and 5000 K. The lighting output of the WLEDs with high CCTs (4000 -5000 K) is deemed as enhanced with increasing green-phosphor concentration. The lower CCT shows greater lumen output when using a lower concentration of BaAl1.4Si0.6O3.4N0.6:Eu 2+ . This tendency also takes place in the case of color uniformity. Conversely, the high concentration of the phosphor is not favourable to the color rendition property of the WLED because of the excessive green-light proportion. It is recommended to keep the concentration of BaAl1.4Si0.6O3.4N0.6:Eu 2+ staying below 10 wt% for better color fidelity.

The effects of red light-emitting phosphor CaMgSi2O6:Eu2+,Mn2+ on the optical properties of single-layer remote phosphor structure (SRPS) and dual-layer remote phosphor structure (DRPS) are the focus of this study. The differences in color quality and luminous flux (LF) of white light-emitting diodes (WLEDs) between these two structures are also revealed and demonstrated based on the Mie theory. SRPS consists of one mixed phosphor layer betweenCaMgSi2O6:Eu2+,Mn2+ andYAG:Ce3+particles, while DRPS includes two separated layers: red phosphor layer and yellow phosphor layer. In this work, 5% SiO2 is added into the phosphor layers to increase scattering abilities. Discrepancies in structures greatly affect the optical characteristics of WLEDs. The results showed that the color rendering index (CRI) increased with the concentration in both structures with nearly equal values. Meanwhile, color quality scale (CQS) of DPRS is 74 at ACCTs ranging from 5600K to 8500K, higher than CQS of SRPS which is only 71 at 8500K. In addition, the luminous flux of DRPS is significantly higher than SRPS at 2% -14% of CaMgSi2O6:Eu2+,Mn2+. In summary, DRPS is better for color quality and lumen outputin comparison to SRPS and adding the right amount of red phosphor can enhance CQS and LF.