Photochromic Clock
Clock that glow in the dark
Screenshots
Hunter's comment
The product employs an array of UV LEDs that illuminate a photochromic face while the part of the glowing screen, the material shines at first with response to the LEDs and then it stays ‘on’ after they turn off, showing four numbers.
Link
https://www.instructables.com/id/Photochromic-Glow-in-the-Dark-Clock/
This is posted on Steemhunt - A place where you can dig products and earn STEEM.
View on Steemhunt.com