Although the distant phosphor configuration is a good selection for high-luminescence WLEDs, it did not satisfy the high color adequacy standard. With the aim of achieving improved chromatic indices, including the index for color rendering (CRI) and the scale of color quality (CQS), for the distant phosphor structure, a dual-layer design with red or green phosphor addition is suggested in this research report. The color temperature of the WLEDs packets employed in this investigation is 8500 K. The phosphor configuration will be produced by layering green Sr3WO6:U or red LaOF:Eu3+ phosphor on top of the yellow phosphor YAG:Ce3+. The concentration of additional red phosphor LaOF:Eu3+ and green phosphor Sr3WO6:U will then be adjusted to observe the changes in color in luminescence performance of the WLED packages. The theory of Mie about scattering combined with Lambert Beer’s rule supports the investigation on optical results. The findings demonstrated a rise in CRI and CQS along with the existence of LaOF:Eu3+, indicating that the LaOF:Eu3+ presence has a major impact on these two elements. Because of the increased concentration of red light components within WLED packets, CRI and CQS increase with increasing concentration of LaOF:Eu3+. In the meantime, the green phosphor Sr3WO6:U improves the beams of light. However, if the concentrations of both the red LaOF:Eu3+ and the green Sr3WO6:U phosphors are above the corresponding level, the beams of light and color intensity will be reduced. The outcomes of this study are crucial references for producing WLEDs with greater light of white standard.

Since TiO2 nanoparticles and silicon composites include a strong scatter influence, they are well-known for improving scattered lighting in LED packets. To improve the optic quality of LEDs packaged with chip-on-board (COB), a thin layer made of high-concentration TiO2 and silicon glue is added to the primary packing layer. COB LEDs’ light extraction efficiency (LEE) rises up to 65% when the key encapsulation includes just silicone, according to the findings of experiments. As a coating of TiO2 and silicone is added, however, the increase in LEE is dependent on the TiO2 concentration. The LEE can be increased from 6% to 24% as the concentration of nanoparticles drops to 0.035 g/cm3. Furthermore, at a mean correlated color temperature (CCT) of around 8500 K, the TiO2/silicone compounds layer will assist in lowering the angular correlated color temperature (CCT) variance between 900 and 470 K within the -90° to 90° observing angle range.