Belshazzar's Clock, luminous paint night clock
There should have been a video here but your browser does not seem to support it. Over a number of years, I’ve experimented with various projects which use luminous paint and ultra violet LEDs to make raster or vector displays. You can see an indifferent video of the very first one here:
Belshazzar's Clock, luminous paint night clock launched on January 8, 2025 with 73 votes, #422 of 6,142 launches that month and more than 95% of that year's launches. The site was still online in September 2026, 1 year on.
In plain words
Belshazzar's Clock is a night clock featuring luminous paint that glows in the dark. Designed for use in bedrooms or other low-light environments, it allows users to tell time without turning on lights. The clock is built for anyone who needs to check the time during nighttime hours while maintaining dark conditions for sleep. Its luminous display is the key feature that distinguishes it from standard timepieces.
written from the facts on this page · September 2026
From the sources
Over a number of years, I’ve experimented with various projects which use luminous paint and ultra violet LEDs to make raster or vector displays. You can see an indifferent video of the very first one here: As these displays were mainly intended as installations at Maker Faires and EMF Camp, they tended to be on the big side, around 2 metres long and 500 mm to 1.5 metres high. Accordingly, they never found permanent homes, and because of the general pressures of installation work, there are only a couple of rough videos to record their existence. Here’s another one of Belshazzar 2, which was a vector display with a low power UV laser: Belshazzar’s feast, or the story of…from blog.karliner.net
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