High refractive index of melanin in shiny occipital feathers of a bird of paradise

作     者：Doekele G Stavenga Hein L Leertouwer Daniel C Osorio Bodo D Wilts 

作者机构：Computational PhysicsUniversity of Groningen9747 AGThe Netherlands School of Life SciencesUniversity of SussexBrightonBN19QGUK Adolphe Merkle InstituteUniversity of FribourgCH-1700 FribourgSwitzerland 

出 版 物：《Light(Science & Applications)》 (光（科学与应用)（英文版）)

年 卷 期：2015年第4卷第1期

页      面：518-523页

核心收录：

学科分类：0808[工学-电气工程] 080901[工学-物理电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 080401[工学-精密仪器及机械] 0804[工学-仪器科学与技术] 0805[工学-材料科学与工程（可授工学、理学学位）] 0803[工学-光学工程] 0702[理学-物理学] 

基　　金：This study was financially supported by AFOSR/EOARD (grant FA8655-08-1-3012) 

主　　题：bird of paradise interference reflector iridescence Jamin-Lebedeff microscopy multilayer 

摘      要：Male Lawes’s Parotia,a bird of paradise,use the highly directional reflection of the structurally colored,brilliant-silvery occipital feathers in their courtship *** in other birds,the structural coloration is produced by ordered melanin *** barbules of the Parotia’s occipital feathers,with thickness,3 μm,contain 6–7 layers of densely packed melanin rodlets(diameter,0.25 μm,length,2 μm).The effectively,0.2 μm thick melanin layers separated by,0.2 μm thick keratin layers create a multilayer interference *** measurements yielded peak wavelengths in the near-infrared at,1.3 μm,i.e.,far outside the visible wavelength *** the Jamin-Lebedeff interference microscopy method recently developed for pigmented media,we here determined the refractive index of the intact *** thus derived the wavelength dependence of the refractive index of the barbules’melanin to be 1.7–1.8 in the visible wavelength *** the anatomical and refractive index data in an optical multilayer model,we calculated the barbules’reflectance,transmittance and absorptance spectra,thereby confirming measured spectra.