Some of Morpho butterflies are well known with its brilliant metallic blue wings. The blue luster is produced from the butterfly's scale that is composed of almost transparent cuticle protein. The origin of the coloration is then not pigment but rather microscopic structure. The principle of this phenomenon has long been referred to as grating or multilayer that can also explain its high reflectivity. However, its optical characteristics on the scattered wavelength cannot be explained by grating or multilayer. The mystery of the lack of multi-coloration (it appears blue from wide angle) remained unnoticed for many years. This mysterious feature has recently been explained with a peculiar optical structure that includes discrete multilayers. This model is based on both of the order and disorder structures: it is not their simple medium but their delicate combination. However, a theoretical hypothesis needs a proof by experiments and we tried to fabricate the optical film by controlling the parameters. A simple fabrication process including a conventional lithography technique in the semiconductor industry was used from viewpoint of application. The result showed that the optical scattering property was basically reproduced and affected by the structure of 100-300 nanometer scales in agreement with the anticipation. A wide variety of applications are relevant to such artificial structural color.

Date Published: 15 October 2004
PDF: 7 pages
Proc. SPIE 5526, Optical Systems Degradation, Contamination, and Stray Light: Effects, Measurements, and Control, (15 October 2004); doi: 10.1117/12.559086

Published in SPIE Proceedings Vol. 5526:
Optical Systems Degradation, Contamination, and Stray Light: Effects, Measurements, and Control
John C. Fleming; Philip T. C. Chen; Michael G. Dittman, Editor(s)