Citation

Jou JH, Kumar S, An CC, Singh M, Yu HH, Hsieh CY, Lin YX, Sung CF, Wang CW. Opt. Express 2015; 23(11): A576-81.

Copyright

(Copyright © 2015, Optical Society of America)

DOI

unavailable

PMID

26072882

Abstract

Increasing studies report blue light to possess a potential hazard to the retina of human eyes, secretion of melatonin and artworks. To devise a human- and artwork-friendly light source and to also trigger a "Lighting Renaissance", we demonstrate here how to enable a quality, blue-hazard free general lighting source on the basis of low color-temperature organic light emitting diodes. With the use of multiple candlelight complementary emitters, the sensationally warm candle light-style emission is proven to be also drivable by electricity. To be energy-saving, highly efficient candle-light emission is demanded. The device shows, at 100 cd m^-2 for example, an efficacy of 85.4 lm W^-1, an external quantum efficiency of 27.4%, with a 79 spectrum resemblance index and 2,279 K color temperature. The high efficiency may be attributed to the candlelight emitting dyes with a high quantum yield, and the host molecules facilitating an effective host-to-guest energy transfer, as well as effective carrier injection balance.

Language: en