11 March 2021, 4:18 am EST By Yu-Mo Zhang and his colleagues at Jilin University in Changchun, China, have created one of the thinnest electrochromic e-reader prototypes ever produced. It is even more notable that it can seamlessly transition from complete transparency to displaying words with high quality and color intensity. (Photo : Nick Jones / Unsplash) The Discovery Of Electrochromic Display The e-reader is made from a laser-etched page of words between two glass sheets, about a quarter of a millimeter thick. The page sandwiched between the glass sheets is actually a solution of copper ions and black dye molecules. The dye molecules bond with the copper ions when exposed to electrical currents, creating the black etched words.