Researchers show why blues and greens are the brightest in nature Researchers in the Vignolini group have shown why structural colour in nature produces blue and green hues which appear much brighter than red, yellow or orange.
Image of blue Macaw, courtesy Will Zhang, Pixabay Structural colour, which is seen in some bird feathers, butterfly wings or insects, is not caused by pigments or dyes, but internal structure alone. The appearance of the colour, whether matt or iridescent, depends on how the structures are arranged at the nanoscale.
Researchers from Professor Silvia Vignolini’s research group used a numerical experiment to determine the limits of matt structural colour, and found that it extends only as far as blue and green in the visible spectrum. The results could be useful in the development of non-toxic paints or coatings with intense colour that never fades.
Ordered, or crystalline structures result in iridescent colours, which change when viewed from different angles. Disordered, or correlated structures result in angle-independent matt colours, which look the same from any viewing angle, and produce some of the most intense colours in nature.
“In addition to their intensity and resistance to fading, a matt paint which uses structural colour would also be far more environmentally-friendly, as toxic dyes and pigments would not be needed,” said first author Gianni Jacucci. “However, we first need to understand what the
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Nathan Pitt
Research
