Structural color, which is the foundation that makes things like a peacock's tail feathers appear iridescent, has been an area of study for scientists as they try to adapt it for use in everyday technologies – only without the “rainbow effect” that makes the colors unstable depending on the angle of view. Now, Researchers at the University of Michigan have mimicked the peacock's color mechanism in an approach that could lead to high resolution reflective color displays and have implications for data storage, cryptography and counterfeiting.
Structural coloration is caused by the interference of light as it travels through and reflects off several microscopically fine layers of a surface structure, thus differing to the production of color by chemical pigments absorbing parts of visible light. The grooves that are also found within a structural formation must be small enough to interfere with the wavelength. The net result of this is that each different hairline groove reflects certain parts of the visible spectrum. By thinking of rainbow-play on soap bubbles, some sea-shells or even the underside of a compact disc, we can see its effects within everyday objects.
The problem with replicating such a structure is that its inherent complexity results in “shimmering” or shifting color. Engineers and researchers have long tried to harness the properties of structural color, and this is especially true in more recent times regarding its use within reflective displays such as e-book readers and next-gen electronic paper displays. In a step forward, a team of University of Michigan researchers, led by Jay Guo, professor of electrical engineering and computer science, have been able to “lock in” certain parts of a wavelength, making the reflected hues hold true despite changes in the angle of view.