Distribution of reflection spectrum for the photonic-crystal structure of Morpho butterfly wing under oblique incidence

In this paper, the authors investigate the optical reflection phenomena of the periodic nanostructure of a Morpho butterfly wing under the oblique-incident light condition. Also, they discuss the simulation of butterfly wings under the view of an optical grating and photonic crystal by using rigorous coupled-wave analysis method and plane wave expansion, respectively. The simulation results show that the displaced lamella is the foremost condition of the reflection light having strong frequency stability under oblique incidence. Moreover, the modified photonic density of state is proposed to evaluate the reflection feature under oblique incidence.