The Modeling of Two Phosphors in Conversion White-Light LED

Because of the high color rendering property, the two phosphors that convert into white light in a light-emitting diode are essential in the general lighting applications. Predicting the spectrum after two phosphors mix is challenging because of the mutual interaction between the absorption of long wavelength phosphor and the emission of short wavelength phosphor. To efficiently model the target spectrum, this paper provides a systematic method for simulating the concentration and proportion of two phosphors by using empirical equations. The simulated and experimental spectra overlapped effectively. The results show that the maximum differences are about 0.0046 for CIE 1931 color coordinates (x, y), about 59 K for correlated color temperature, and about five for color rendering index, respectively. The results show that this spectral optimization is an effective approach.