Research On The Corelated Color Temperature Of LED White Light

As a new type of green lighting light source, LED(Light Emitting Diode) with low temperature, small power, energy saving, long life and other characteristics becomes a new generation illumination advocating environmental protection and low carbon emission in the world wide. This thesis mainly studies on the two aspects of white LED: 1) the calculation of new correlated color temperature, and 2) result analysis on the fast simulation with different fitting curves.1. The definition of correlated color temperature(CCT) and the contradiction of CCT in three different uniform chromaticity diagrams(CIE1960UCS, CIE1976 UCS and CIE1976LAB) are investigated, and a new method based on single-dimension of hue is proposed. The corresponding relation between color temperature(CT) and hue was established in the Munsell color system, and the new iso-temperature lines in three uniform chromaticity diagrams are delineated by ignoring the influence of saturation on CT. The bisection numerical method is employed to calculate the CCT of a light source. By comparing the new method for CCT with the traditional method, the physics meaning is clearer, and low difference is existed in the results from different chromaticity diagrams.2. There are three important factors to improve high quality LED lighting: the improvement of the luminescent efficiency, the control of lighting pattern and the color uniformity on target plane. And the high power LED computer simulation has got more attention and research.Color uniformity has been less used for the optimization due to the huge amount of data and other issues. Therefore, we come up with the idea of fast simulation. By using different fitting formulas, we discuss the effect of them. Finally, we take experimental test on the LED sample and get its light spot. The simulation and experimental results were compared to analyze the correlated temperature, and it shows that using fast simulation can greatly reduce the complexity and the time,and the colorimetric distribution is also close to the real distribution of chromaticity.