Japan Display Inc showcased e-paper like LCD 11 years ago. It even has e-paper features like retained pixel at low power consumption. With further work notetaking will be possible. https://www.youtube.com/watch?app=desktop&v=mdXu9jmTI2A
Some 10 to 15 years ago many companies worked on reflective screens, but most all seem to have been abandoned following the dominance of E Ink's monochrome electrophoresis displays.
