Directionally Controlled Fluorescence Emission in Butterflies

University of Exeter, Exeter, England, United Kingdom
Science (Impact Factor: 33.61). 12/2005; 310(5751):1151. DOI: 10.1126/science.1116612
Source: PubMed


Recently developed, high-efficiency, light-emitting diodes use two-dimensional photonic crystals to enhance the extraction of otherwise internally trapped light and multilayer reflectors to control the direction of light emission. This work describes the characterization of a naturally evolved light-extraction system on the wing scales of a small group of Papilio butterflies. The efficient extraction of fluorescence from these scales is facilitated by a two-dimensional photonic crystal slab that uses a multilayer to help control emission direction. Its light-extraction function is analogous to that of the light-emitting diode.

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    • "The former is caused by the exchange of energies between light and the electrons of pigments, while the latter can be explained as a pure physical interaction between light and various spatial inhomogeneity [17] . The green scales of butterfly Papilio nireus have a layer of air-filled alveoli, whose axis is perpendicular to the scale surface [13] . Recently, studies on butterfly wings show that some microstructures on its wings surface are effective solar collectors [18] or blocks [19] . "
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