US Patent 7768640 Fluorescence detection enhancement using photonic crystal extraction

Enhancement of fluorescence emission from fluorophores bound to a sample and present on the surface of two-dimensional photonic crystals is described. The enhancement of fluorescence is achieved by the combination of high intensity near-fields and strong coherent scattering effects, attributed to leaky photonic crystal eigenmodes (resonance modes). The photonic crystal simultaneously exhibits resonance modes which overlap both the absorption and emission wavelengths of the fluorophore. A significant enhancement in fluorescence intensity from the fluorophores on the photonic crystal surface is demonstrated.