Reflectance measurements and optical simulation of spectral filters in Philippine beetle

Abstract

Interesting photonic assemblies in nature are continuously discovered and characterized because of their ingenuity and sophistication which often inspire biomimicry. The natural optical filter found in a Philippine beetle is characterized via reflectance experiments and modeled as a multilayer stack of air and chitin planes. Geometric parameters are predicted via Bloch’s theorem, and reflected spectra are simulated using ray transfer matrices. Results are consistent with the observed iridescent behavior of the insect.