Abstract
Along with development of civilization, lighting has been widely used in our lives. With the large progress in production and luminous efficiency, light-emitting diodes (LED) are more and more popular in commercial applications such as displays, flashlights, back light units, and etc. Even though not many LED luminaries are available in the market, LED illuminations are still expected to replace traditional light sources in the near future. Due to increasing energy consumption and shortage of oil production, the need to develop better energy-saving and environmentally-green technology is essential. Therefore, applications of High Brightness (HB) LED in lighting industry are important goals to be achieved. HB-LED is high in efficiency, low in energy consumption, long-life in life-span, fast in ignition, small in size, and light in weight; and, it does not contain poisonous mercury which leads to recycle problems as fluorescent tubes do. In this study, white LEDs are supplemented with a red LED for design of HB LED light sources with high color rendering index (CRI). At first, experiments and optical simulations via ASAP are benchmarked for fluorescent sources. Then, models for HB LED and experiments are established for validation of the HB LED models plus a program to calculate mixing of various colors for the best CRI. Finally, two methods are adopted for design of HB LED with high CRI plus better uniformity compared to the fluorescent tubes.