Little dated (2012) but basic material properties of eink has not changed: https://archive.nytimes.com/www.nytimes.com/interactive/2012/12/26/technology/light-

Little dated (2012) but basic material properties of eink has not changed: https://archive.nytimes.com/www.nytimes.com/interactive/2012/12/26/technology/light-reading.html https://archive.nytimes.com/www.nytimes.com/interactive/2012... Eink due to its USP and fundamental characteristics only reflects light and does not transmit (i.e., is not transparent. Transparency is needed for back lighting).