MICROSTRUCTURES AND OPTICAL-PROPERTIES OF SCALES OF BUTTERFLY WINGS

This paper describes the mechanism generating the beautiful wing color s of various male butterflies and the relationship between the wing ma terial and the color appearance. The microstructure of the scales cove ring the upper surface of the wings was analyzed with the aid of a sca nning electron microscope. The basic mechanism of color generation of structurally colored scales is determined for the first time in accord ance with the theory of optical interference in thin film layers using a model of wing scales. Optical properties were found in relation to the three-dimensional spectral reflectance of the samples, and differe nces were observed between the brightness perceived in subjective eval uations and calculated values based on the reflective spectra of the s tructurally colored wings. The results of this study suggest that the microroughness of the upper wing surface may influence the perceived g loss of structurally colored wings.