固態照明是現代社會不可或缺的一部分，它為人類的生活方式帶來巨大變化，使文明得以快速發展，一高品質照明光源不僅應具備節能的優點，更要對人體友善，因其光色及亮度對人體生理時鐘與晝夜節律有異常重大影響。
現今市面上的照明光源大多富含藍光，而許多研究證實，入夜後，光源中藍紫光會強烈抑制褪黑激素分泌，造成失眠、二類型糖尿病、肥胖及心血管疾病，長期下來，將導致乳癌與攝護腺癌罹患率攀升，故黃昏後應使用低色溫、無藍害之照明，而長期未照射藍光又會引發憂鬱症、導致自殺率提升；因此，製作一高效率光源，其色溫可在無藍光的低色溫及少量藍光的中低色溫間調節，不僅可滿足人們對於人體友善光源之需求，也能減少能源的損耗。
本研究使用供體材料 9,9'-Diphenyl-9H,9'H-3,3'-bicarbazole (BCzPh)及受體材料 2,4,6-tris(2-(1H-pyrazol-1-yl)phenyl)-1,3,5-triazine [3P-T2T] 組成複合激子共主體，並加入2.5 wt%紅光客體 Bis(2-(3,5-dimethylphenyl)quinoline-C2,N')(acetylacetonato)iridium(III) [Ir(mphq)2acac]與5 wt%綠光客體 Tris(2-phenylpyridine)iridium(III) [Ir(ppy)3] 作為第一發光層，並使用供體材料 Tris(4-carbazoyl-9-ylphenyl)amine [TCTA]與受體材料 1,3,5-Tri(m-pyridin-3-ylphenyl)benzene [TmPyPB] 組成另一複合激子共主體，並加入0.05 wt%綠光客體 Tris(2-phenylpyridine)iridium(III) [Ir(ppy)3]與8.0 wt%藍光客體 (FIrPic)作為第二發光層，製作出一高效率色溫可調有機發光二極體，在100 cd/m2下，能量效率為25 lm/W，外部量子效率為15 %；其光色在 CIE 1931色彩空間上可呈現日落前20至1分鐘之夕陽光色軌跡；元件效率高可歸因如下：(1)良好的元件結構設計，使電子及電洞有較低的注入能障，再加上發光層中良好的載子平衡；(2)供體、受體間最高填滿分子軌域及最低未填滿分子軌域的能階差異大，使電子、電洞可以累積在同一介面，有利複合激子的形成；而色溫完全貼合黑體輻射軌跡可歸因於：(1)使用了三種可包圍黑體輻射軌跡之色域的黑體輻射互補性染料；(2)電壓增加後，較多激子注入能階較大的藍光客體，使得紅、綠及藍光的相對強度有所改變。

Solid-state lighting is an indispensable part of modern society. It brings great changes to human life and accelerates the development of civilization. A high-quality lighting source should be energy saving and friendly to human body, because its light color and brightness have significant impacts on human body's biological clock and circadian rhythm.
Nowadays most of the lighting sources on the market are rich in blue light, and according to several researches, blue-violet light at night strongly suppresses the secretion of melatonin, causing insomnia, cardiovascular disease, obesity and type 2 diabetes, and long term consequences of that will lead to breast cancer, and rise rates of prostate cancer. Therefore, blue light-less lighting with low color temperature should be used after dusk. In addition, long-term non-exposure to blue light will cause depression and increase the suicide rate. Therefore, a high-efficiency light source whose color temperature can be adjusted between a low color temperature with no blue light and a medium and low color temperature with a small amount of blue light can not only meet people's needs for a human-friendly light source, but also reduce energy consumption.
In this study, donor material 9,9'-Diphenyl-9H,9'H-3,3'-bicarbazole (BCzPh) and acceptor material 2,4,6-tris(2-(1H-pyrazol-1-yl )phenyl)-1,3,5-triazine [3P-T2T] were combined to form the first emissive layer (as exciplex co-host) via doping 2.5 wt% red dye Bis(2-(3,5-dimethylphenyl)quinoline-C2,N')(acetylacetonato)iridium(III) [Ir(mphq)2acac] and 5 wt% green dye Tris(2-phenylpyridine) iridium(III) [Ir(ppy)3]. Donor material 1,3,5-Tri(m-pyridin-3-ylphenyl)benzene [TmPyPB] and acceptor material Tris(4-carbazoyl-9-ylphenyl)amine [TCTA] were combined to form the second emissive layer (also as exciplex co-host) via doping 0.05 wt% green dye Tris(2-phenylpyridine) iridium(III) [Ir(ppy)3] and 8.0 wt% blue dye (FIrPic). At 100 nits, the manufactured high-efficiency device has a power efficacy of 25 lm/W and an external quantum efficiency of 11 %. Its light color can present the sunset light color trajectory 20 to 1 minute before sunset on the CIE 1931 xy coordinates. the high efficiency of it was due to the following reasons: (1) Good device structure design that makes electrons and holes to have a lower injection barrier, and good carrier balance within the emissive layer. (2) The energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of donor and acceptor are large, so that holes and electrons can accumulate at the same interface, which is beneficial to the formation of exciplexes. The color temperature is completely matched the blackbody radiation locus can be due to: (1) the application of three blackbody radiation complementary dyes that can encompass the color gamut of the blackbody radiation locus; (2) after the voltage is increased, more excitons are injected into the blue light guest which has a larger band gap, so the relative intensity of red, green, and blue light changes.

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