These are the smallest pixels to ever exist. A team of scientists led by the University of Cambridge in the UK have developed what are now known as the smallest pixels ever. As it is, these newly developed pixels are a million times smaller than those tiny specs you have inside your smartphone’s high-resolution display.
At the centre of each pixel is a tiny particle of gold which is a few billionths of a metre in diameter. The grain sits on top of a reflective surface, trapping light in the gap between the surface and the particle. The scientists then sprayed the grains with an polymer called polyaniline. This is then wrapped with a thin yet sticky coating which changes chemically when electrically switched, and that makes the pixel change colour across the spectrum. These pixels can be seen in bright sunlight and because they do not need constant power to retain the set colour. But the biggest advantage perhaps is the low energy requirement, which means very large displays, perhaps the sizes that cover entire buildings, would be feasible to make and sustainable to operate.
“These are not the normal tools of nanotechnology, but this sort of radical approach is needed to make sustainable technologies feasible. 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,” said Professor Jeremy J Baumberg of the NanoPhotonics Centre at Cambridge’s Cavendish Laboratory, who led the research.
The research was funded as part of a UK Engineering and Physical Sciences Research Council (EPSRC) investment in the Cambridge NanoPhotonics Centre, as well as the European Research Council (ERC) and the China Scholarship Council.