The first one I heard about was 10-15 years ago by projecting an image on the tongue. Ahh, here it is: https://www.scientificamerican.com/article/device-lets-bl

The first one I heard about was 10-15 years ago by projecting an image on the tongue. Ahh, here it is: https://www.scientificamerican.com/article/device-lets-blind-see-with-tongues/ https://www.scientificamerican.com/article/device-lets-blind...