You could certainly be forgiven for thinking that the term “digital sundial” is simply an example of an oxymoron, not unlike “jumbo shrimp” or “deafening silence.” That hasn’t stopped French Thingiverse member Mojoptix from building one, however. It contains no electronics or moving parts, yet it still shows the time from 10:00 to 16:00 in a changing numerical display – with a little help from the sun.
First of all, there are indeed other digital sundials, although they generally don’t have the traditional shadow-casting sundial form factor. Instead, they utilize optical fibers or layered masks, and are viewed face-on like a clock.
By contrast, Mojoptix’s creation has the usual angled pointy bit in the middle (known as a gnomon), the shadow of which moves around in a circular path as the sun traverses the sky. Instead of pointing to numbers on the ground, however, that shadow displays the time in 20-minute increments within itself as it moves.
via Gizmag
Image: Mojoptix
