He Guoxing, Tang Ju
Opt Lett. 2014 Oct 1;39(19):5570-3. doi: 10.1364/OL.39.005570.
The optimization model of limited luminous efficacy (LLE) for correlated color temperature (CCT) tunable phosphor-coated white light-emitting diodes (pc-W LEDs) consisting of blue chips, green and yellow phosphors, and red chips, including downconversion energy loss, has been developed under the constraint of a designated color-rendering index (CRI) and a special CRI of R9 for strong red. The optimal spectra of pc-W LEDs are obtained with a nonlinear program for maximizing LLE under conditions of both CRI and R9 above 90, 95, and 98 at CCTs of 2700-6500 K. The pc-W LEDs with LLE>301 lm/W for both CRI and R9 above 90, LLE>290 lm/W for both CRI and R9 above 95, and LLE>276 lm/W for both CRI and R9 above 98 could be achieved at CCTs of 2700-6500 K. The recommended peak wavelengths and full widths at half-maximum (FWHMs) for the current LEDs and phosphors and their photometric and colorimetric performances are presented.
针对由蓝色芯片、绿色和黄色磷光体以及红色芯片组成的相关色温（CCT）可调谐涂覆磷光体的白光发光二极管（pc-W LED），开发了包括下转换能量损失在内的有限发光效率（LLE）优化模型，该模型是在指定显色指数（CRI）和用于强红色的特殊R9显色指数的约束条件下建立的。通过非线性规划，在2700 - 6500K的CCT下，当CRI和R9分别高于90、95和98时，获得了使LLE最大化的pc-W LED的最佳光谱。在2700 - 6500K的CCT下，可以实现CRI和R9均高于90时LLE>301 lm/W、CRI和R9均高于95时LLE>290 lm/W、CRI和R9均高于98时LLE>276 lm/W的pc-W LED。给出了当前LED和磷光体的推荐峰值波长和半高宽（FWHM）及其光度和色度性能。
