Abstract
The theory of the optical properties of an absorbing periodically stratified medium is applied to the spectral and angular dependence of the reflectivity of mollusk shells, which are almost-periodic structures of aragonite plates alternating with thinner organic layers. The reflectivity of s and p polarizations show strong variation as the angle of incidence passes through the stop bands of the corresponding ideal non-absorbing periodic structure. For both polarizations of incident light, and at most angles of incidence, the blue and green wavelengths are reflected more than the red—hence the blue-green appearance of mollusk shells.
Subject
Computer Vision and Pattern Recognition,Atomic and Molecular Physics, and Optics,Electronic, Optical and Magnetic Materials