Coloration and Structure of the coleoptera of Taiwanese bronze scarab (Anomala expansa) and Taiwanese Iridescent Gold Scarab (Mimela splendens)

• Main Authors: WU, MIN-NAN, 吳敏男
• Other Authors: PAN, WEI
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/6nx78x

博士 === 國立中正大學 === 物理系研究所 === 105 === This paper is to correlate the structural and optical characteristics of elytras of two beetles Anomala expansa and Mimela splendens. The first beetle’s elytron is composed by a scale-like texture on the surface and a repeated bi-layers underneath. The reflectivity spectrum shows iridescence that the peaks shifts from yellow to green color regions as long as the incident angle (θ) increases. A shoulder peak at 600 nm (θ = 20⁰) is absent after gently scraping the surface, which indicates that the yellow color is contributed by the scale-like texture. The remaining peak at 550 nm (θ= 20⁰) in the spectrum resembles the simulated spectrum by assuming the refractive index of n = 1.54 and n = 1 for the adjacent bi-layered structure. This implies that the multi-layered structure contributes to the green coloration as well as the iridescent effect. Another paper is to correlate the structural and optical characteristics of elytras of a beetle Mimela splendens by microscopy, angle-dependent reflection spectra, and theoretical calculations. Given the nanostructure, a good fit is achieved between the calculation and experiments, which contain the structural patterns and the refractive indices of the elytra layers. This structural-optical correlation may provide a bio-inspired material in industry and benefit in environment protection.