11 April 2014 Candlelight style organic light-emitting diode: a plausibly human-friendly safe night light
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J. of Photonics for Energy, 4(1), 043598 (2014). doi:10.1117/1.JPE.4.043598
Candles emit sensationally warm light with a very low color temperature, comparatively most suitable for use at night. In response to the need for such a human-friendly night light, we demonstrate the employment of a high number of candlelight complementary organic emitters to generate and mimic candlelight based on organic light emitting diode (OLED). One resultant candlelight style OLED shows a very-high color rendering index (CRI), with an efficacy at least 300 times that of a candle or at least two times that of an incandescent bulb. The device can be fabricated, for example, by using four candlelight complementary emitters: red, yellow, green, and sky-blue phosphorescent dyes. These dyes, in the present system, can be vacuum deposited into two emission layers that are separated by a nanolayer of carrier modulation material that is used to maximize very high CRI and energy efficiency. A nano carrier modulation layer also played a significant role in maintaining the low blue emission and high-red emission, the low color temperature of device was obtained. Importantly, a romantic sensation giving and supposedly physiologically friendly candlelight style emission can hence be driven by electricity in lieu of hydrocarbon burning and greenhouse gas-releasing candles that were invented 5000 years ago.
Jwo-Huei Jou, Chun-Yu Hsieh, Po-Wei Chen, Sudhir Kumar, James H. Hong, "Candlelight style organic light-emitting diode: a plausibly human-friendly safe night light," Journal of Photonics for Energy 4(1), 043598 (11 April 2014). http://dx.doi.org/10.1117/1.JPE.4.043598

Organic light emitting diodes

Light sources and illumination

Light emitting diodes


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