CaCO3 and TiO2 are proposed in this study as particles for scattering enhancement (SEPs) of phosphor-converted white light-emitting diodes (pc-WLEDs). The use of these two SEPs for scattering improvement enables boosting of the color homogeneity of the WLED devices. Each SEP is mixed with YAG:Ce3+ and silicone composition to examine their optical influences and performances on the high-power WLED packages with 7,000 K color temperature (CT). Miescattering theory is applied to calculate and investigate the scattering elements - scattering coefficients, anisotropic scattering, the reduced scattering, and scattering amplitudes - at the wavelengths of 450 nm and 550 nm. The results exhibit that TiO2and CaCO3 considerably promote higher color uniformity and color-deviated reduction, respectively. The obtained results could be primarily attributed to the significant improvement in the scattering properties of the structure. Additionally, the effects of the presented scattering enhancement on luminous efficiency are displayed. The reduction in lumen output is observed to have a close connection with the concentration and particle size of TiO2and CaCO3, which means that control must be exercised over these factors when utilizing these SEPs for WLED fabrication.
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W artykule zostały zaprezentowane wyniki badań doświadczalnych, których celem było określenie wpływu zmian temperatury otoczenia na pracę opraw z diodami LED przede wszystkim na wartość strumienia świetlnego. Na podstawie przeprowadzonych badań oszacowano wpływ temperatury na skuteczność świetlną oprawy.
EN
In the paper the experimental results were presented, which the main aim was estimate an influence of ambient temperature on LED luminaries (luminous flux). On the base of experimental researches the influence of ambient temperature on the luminous efficiency of a LED luminaire.
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