Impact of the design parameters uncertainty on the PC-white LED color constancy based on the theory of the uncertainty

Abstract

The white LED color constancy is a challenge for the LED design and packaging. The color binning process is used to deal with this challenge by many manufacturers. The new ideas of “Freedom From Binning” and “Hot testing” were brought out by Philips recently. The Philips approach mainly depended on the Lumiramic phosphor technologies, which improved the uniformity of phosphors coating layer thickness. In this paper, according to the theory of the mix-color, the simulation model was built in MATLAB and the performance of the white LED was analysized based on the model. According to the theory of uncertainty, one uncertainty model of the two primary colors LED's color deviation, correlated color temperature and luminous flux was built which takes the uncertainty of the design parameters, such as the monochromatic spectral wave length, half wave width, into accounting in MATLAB. The probability distribution of the LED color deviation was obtained under the normal probability distribution of the design parameters. The impact of the uncertainty of the design parameters on white LED performance was firstly quantified. The new approach design with improved the LED color constancy was brought out. The paper will give a theoretical and technical foundation of LED color constancy and offer an effective approach for improving the LED color performance.