Peacock Feather Barbule — Structural Colour at 6:1
30.16 د.ك
A peacock tail feather’s eye-spot barbule photographed at 6:1 macro — the nanostructure of the barbule surface that produces structural colour visible as iridescent bands of green and gold that shift with viewing angle.
Description
The peacock’s iridescent feather colours are produced not by pigment but by the nanostructure of the feather barbule surface — a 2D photonic crystal lattice of melanin rods in a matrix of keratin, the lattice spacing tuned to reflect specific wavelengths through thin-film and multilayer interference. At 6:1 macro magnification, the barbule structure begins to resolve — the individual melanin rods are below optical resolution limits, but the organisation of the barbule surface into the iridescent patches of the eye-spot pattern is fully legible. This image captures the transition zone between the green and gold regions of the eye-spot at 6:1 reproduction, the colour shift occurring over a distance of approximately 0.5mm as the barbule’s nanostructure changes in lattice spacing. The viewing-angle dependence of the structural colour is visible within the single image — the edges of each barbule show a different colour than the central surface due to the changing incident angle of the illumination light.
