Writing with a Magnet (IMAGE) American Institute of Physics Caption The black side of the microparticles contains magnetic nanoparticles that make it possible to write on the screen. A magnet pulled across the surface of the white display attracts the black side and the balls flip to face the magnet. Credit Yusuke Komazaki/ University of Tokyo Usage Restrictions With proper attribution. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.