Nanoparticle screen hits record clarity visible to the human eye

Researchers from Swedish institutions—including Chalmers University of Technology, the University of Gothenburg, and Uppsala University—have developed a groundbreaking display technology called retina E-paper, featuring pixels as small as 560 nanometres. This size is smaller than the wavelength of visible light, enabling a pixel density exceeding 25,000 pixels per inch (ppi), roughly 150 times denser than typical smartphone screens. The display uses tungsten oxide nanoparticles to control light scattering and produce highly accurate, tunable red, green, and blue colors. Unlike conventional LED or OLED screens, retina E-paper is reflective, relying on ambient light rather than emitting its own, which significantly reduces energy consumption and allows the screen to be positioned very close to the eye. The retina E-paper’s pixel size corresponds approximately to the size of a single photoreceptor in the human retina, meaning it achieves the maximum resolution perceivable by the human eye. The researchers demonstrated the technology by reproducing Gustav Klimt’s painting “The