Researchers Coat Smallest Pixels with Polymer
A team of scientists at the University of Cambridge have developed the smallest pixels ever created. With the help of a thin coating, the researchers say the development could be used for new types of displays to cover the exterior of buildings.
“At the center of the pixels developed by the Cambridge scientists is a tiny particle of gold a few billionths of a meter across,” according to the university.
“The grain sits on top of a reflective surface, trapping light in the gap in between. Surrounding each grain is a thin sticky coating which changes chemically when electrically switched, causing the pixel to change color across the spectrum.”
The pixels were created by coating vats of those golden grains with polyaniline—an active polymer—and then aerosol spraying them onto the flexible, mirror-coated plastic.
That plastic can be compared to roll-to-roll fabrication, making the innovated much more cost effective than how large displays would typically be produced.
The pixels are the smallest ever created, Cambridge says, and unlike some other displays, can be seen in bright sunlight. They also don’t need constant power to keep their desired colors, giving them another edge for large displays.
“These are not the normal tools of nanotechnology, but this sort of radical approach is needed to make sustainable technologies feasible,” said professor and research lead Jeremy J. Baumberg of the NanoPhotonics Centre at Cambridge’s Cavendish Laboratory.
“The strange physics of light on the nanoscale allows it to be switched, even if less than a tenth of the film is coated with our active pixels. That’s because the apparent size of each pixel for light is many times larger than their physical area when using these resonant gold architectures.”
In addition to large display screens, researchers say the technology could also potentially be used to switch on and off solar heat loads or camouflage coatings.
The research was funded as part of a U.K. Engineering and Physical Sciences Research Council investment in the Cambridge NanoPhotonics Centre, the European Research Council and the China Scholarship Council.