Investigation of the unique color-developing mechanism of the tiger beetle(C. japonica)

Multicolor and gloss controlled by microstructure

Abstract

C. japonica is beetle that has unique color properties, such as various colors on its forewings(red, green, blue, and white) and the difference in glossiness between dorsal and ventral sides. We investigated the origins of these properties by optical measurement, electron microscope, and numerical simulation. As a result, it was clarified that red, green, and blue areas are caused by multilayer interference, while no multilayer film was observed in the white area. Moreover, it was revealed that dorsal side has micro-recessed structure, whereas ventral side has flattened structure, and the difference in these structures leads to the difference in luster.