Ecological color devices by biomimetic nanostructures

Brilliant blue of some Morpho butterfly species is a typical example of the structural color and attracts interest due to a metallic luster from the biological body. The origin of the color can be explained by interference in an ordered microstructure, whereas the blue in too wide angular range contradicts the interference. This mystery is attributed to a specific nanostructure having both order and disorder, and has been proven successfully by emulating the 3D nanostructures. Although wide potential applications of this specific color were found, true applications require a variety of developments, which have recently been overcome step by step.