Abstract
Healthy light has attracted increasing attentions due to recognizing the hazards that modern light has caused to physiology, human eyes, ecology, and artworks. Hence, studies concentrated on the design and fabrication of hazard-free lighting sources has been significantly increasing. However, issues on light quality and energy-saving are of great importance. Here, we present an original approach to enable the generation of human-eye-friendly and melatonin suppression-less healthy light with high light-quality and energy-saving characters. Taking a three-band organic light-emitting diode (OLED) for example, the suppression threat can be reduced by 83% as the color temperature of the resulting light is decreased from 6000 to 2000 K, while slightly sacrificing its theoretical efficacy limit from 260 to 245 lm/W and spectrum resemblance index (SRI) from 90 to 83. Notably, a comparatively more healthy light can be obtained by incorporating lesser deep-blue and -red emissions even at the same color temperature. The same approach can also apply to other lighting technologies such as light-emitting diode.