BBC: A new flexible display uses 300-nm pixels to create images on a surface just 0.07 mm wide and 0.2 μm thick. Harish Bhaskaran of Oxford University and his colleagues created the pixels by sandwiching a phase-change material between transparent electrodes. Phase-change materials switch between crystalline and amorphous states, which makes them useful as heat exchangers and as optical material for rewritable DVDs. Instead of encoding data on the pixels, Bhaskaran’s team used electric current to change the color of the material in each pixel to create non-moving images. By creating screens of different thicknesses, they were able to produce different colors. Each pixel is controlled independently and doesn’t require the electronics to be directly attached to the screen. That means that the screen could be nonintrusive. And, because each pixel is permanent until given another pulse of current, the screen does not have to continuously refresh itself, like conventional LCD screens do. That would reduce its energy consumption.
