Heat and fluid flow in high-power LED packaging and applications

X Luo, R Hu, S Liu, K Wang - Progress in Energy and Combustion Science, 2016 - Elsevier
Light-emitting diodes (LEDs) are widely used in our daily lives. Both light and heat are
generated from LED chips and then transmitted or conducted through multiple packaging …

Measurement and numerical studies of optical properties of YAG: Ce phosphor for white light-emitting diode packaging

Z Liu, S Liu, K Wang, X Luo - Applied optics, 2010 - opg.optica.org
The optical properties of YAG: Ce phosphor were measured by a double-integrating-sphere
system and calculated by Mie theory and Monte Carlo ray tracing to provide precise optical …

Optical analysis of color distribution in white LEDs with various packaging methods

Z Liu, S Liu, K Wang, X Luo - IEEE Photonics Technology …, 2008 - ieeexplore.ieee.org
Uniform color distribution is essential for the packaging of light emitting diodes (LEDs). The
Monte Carlo ray tracing method is applied to analyze the color distribution of white LEDs …

Design of a novel freeform lens for LED uniform illumination and conformal phosphor coating

R Hu, X Luo, H Zheng, Z Qin, Z Gan, B Wu, S Liu - Optics Express, 2012 - opg.optica.org
A conformal phosphor coating can realize a phosphor layer with uniform thickness, which
could enhance the angular color uniformity (ACU) of light-emitting diode (LED) packaging. In …

Effect of phosphor settling on the optical performance of phosphor-converted white light-emitting diode

R Hu, X Luo, H Feng, S Liu - Journal of Luminescence, 2012 - Elsevier
Phosphor settling phenomena exists during the phosphor coating process in the light
emitting diode (LED) packaging industry. It is perceived that phosphor settling will affect the …

Study on the optical properties of conformal coating light-emitting diode by Monte Carlo simulation

R Hu, X Luo, S Liu - IEEE Photonics Technology Letters, 2011 - ieeexplore.ieee.org
The light extraction efficiency (LEE), correlated color temperature (CCT), and angular color
uniformity (ACU) of the conformal coating phosphor silicone gel were investigated by Monte …

A detailed study on the requirements for angular homogeneity of phosphor converted high power white LED light sources

C Sommer, P Hartmann, P Pachler, M Schweighart… - Optical Materials, 2009 - Elsevier
We present a simulation procedure based on optical ray-tracing in order to optimize the
angular homogeneity of the light emitted from the color conversion element (CCE) in a …

Packaging efficiency in phosphor-converted white LEDs and its impact to the limit of luminous efficacy

CC Sun, YY Chang, TH Yang, TY Chung… - Journal of Solid State …, 2014 - Springer
In this paper, we start from the study on the packaging efficiency of the phosphor-converted
white LED via a new way to measure and calculate the blue light from the blue die to the …

Angular color uniformity enhancement of white light-emitting diodes integrated with freeform lenses

K Wang, D Wu, F Chen, Z Liu, X Luo, S Liu - Optics letters, 2010 - opg.optica.org
We demonstrate a freeform lens to enhance the angular color uniformity (ACU) of white light-
emitting diodes (LEDs) whose phosphor layers were coated by freely dispersed coating …

Studies on optical consistency of white LEDs affected by phosphor thickness and concentration using optical simulation

ZY Liu, S Liu, K Wang, XB Luo - IEEE Transactions on …, 2010 - ieeexplore.ieee.org
Effects of variations of yttrium aluminum garnet: Ce phosphor thickness and concentration
on optical consistency of produced white light-emitting diodes (LEDs) including the …