They are a million times smaller than the pixels we have on today's mobile displays: they are obtained by trapping tiny particles of light in tiny gold crystals, and they can be used for a new class of incredibly large screens, enough to cover entire buildings. .
Developed by a team from the University of Cambridge, the (color) nanopixels are compatible with printing on rollers on plastic films, a process that greatly reduces the production cost. The development results were published in the journal Science Advances.
It is a long-standing dream to mimic the chameleonism of octopuses and cuttlefish, allowing people and objects to disappear by camouflaging themselves in the background, but the production of flexible screens on a large scale is still prohibitive due to production costs.
At the center of the pixels developed by Cambridge scientists is a layer of tiny gold particles a few billionths of a meter thick. This layer in turn rests on a reflective surface that "traps" the light in the cavity. Around each "grain" of this layer there is a thin coating of a special glue that changes chemically when it is electrically stimulated, causing the pixel to change color.
The multidisciplinary team of scientists (including chemists, physicists and engineers) developed these pixels respecting maximum energy saving criteria, therefore they do not require constant energy to maintain color, exploiting natural light.
It is a technology that can lead to the development of gigantic screens, buildings capable of reducing the solar heat, clothes and covers capable of changing color and even tiny indicators designed for the internet of things.
The team is currently working on extending the color gamut and is looking for partners to further implement the technology.
Here is the paper: "Scalable electrochromic nanopixels using plasmonics" - Science Advances (2019).