Article

Directionally controlled fluorescence emission in butterflies

University of Exeter, Exeter, England, United Kingdom
Science (Impact Factor: 31.48). 12/2005; 310(5751):1151. DOI: 10.1126/science.1116612
Source: PubMed

ABSTRACT 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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