TITLE:
Remote Pyramid-Shaped Phosphor Coating for Phosphor-Converted White LEDs
AUTHORS:
Sevda Hasan Abdullayeva, Teymur Yashar Orujov, Nahida Nazim Musayeva, Rasim Baba Jabbarov, Samir Kamal Orujov
KEYWORDS:
Light Emitting Diode (LED), Chip-On Board (COB) Package, Light Extraction Efficiency, Total Internal Reflection (TIR)
JOURNAL NAME:
World Journal of Nano Science and Engineering,
Vol.7 No.2,
June
21,
2017
ABSTRACT: Increasing light extraction efficiency is an important task when it comes to manufacturing a powerful white light emitting diode with high luminous flux per watt. In this paper the fabrication of a pyramid-shaped 3-dimensional phosphor coating is reported. It is represented by a phosphor cover, shaped into an array of pyramid like formations. It is proposed that such a structure can improve the light extraction efficiency and the color distribution characteristics of any phosphor-converted white LED. The luminous flux and luminous efficacy are being studied as a function of the forward current across the die. It was found out that with this kind of technique it was possible to achieve an 8% - 14% increase in the efficacy of the pc-LED. This increase of light output power is being attributed to the reduction of the phenomena of total internal reflection (TIR) inside the packaging module.