“I've never seen anything quite like it on the internet before,” writes maker ElliotMade on Instructables (opens in new tab) about his Raspberry Pi (opens in new tab)-powered RGB fiber-optic matrix display, and we’re inclined to agree - this is a truly original build that makes use of its relatively simple components in a rather wonderful way.
At the heart of it all is a Raspberry Pi Pico, which is capable of supplying both power and instructions to the fiber-optic array (though an external power supply would take the strain off the Pico) and some CircuitPython (opens in new tab) code. The 16 x 16 WS2812B (NeoPixel) LED matrix is sold by Adafruit (opens in new tab), and the 1.5mm end-glow PMMA fiber comes from Amazon (opens in new tab).
The display fits together like a sandwich. Most of the parts can be 3D printed, laser-cut, or made by hand. A backplate supplies structural integrity, a second plate in the middle supports the LED matrix, while a front plate with an individual hole for each fiber holds them up to the LEDs. A main display grid, also with holes, brings the fibers together and forms the main display. Various spacers and screws hold the whole thing together.
The build comes from a site-wide contest on Instructables to make things that glow. The great beauty of the fiber-optic approach comes when you send light from the LEDs down the fibers to the display grid - points of light appear, from which you can make patterns or words, but the fibers, which are completely visible, glow too. As they are curved, their glow adds an almost organic look to the background behind the main display, as if some bioluminescent deep-sea creature were powering it instead of a tiny slab of RP2040 silicon. Sending different colors to the display naturally lights up the board in the same hues, producing a restful and mesomeric effect.
ElliotMade (opens in new tab) has been very busy on the site for someone who only signed up in February 2020 - there are eight projects under their name, including a remote-controlled lawnmower, a word clock, and a physical mute button for Zoom meetings. There are also two videos on the ElliotMade YouTube channel (opens in new tab) about the build, one that we’ve embedded above is a demo of the display, while the other takes us through the building of the device.
As for its uses, well, art is its own reward, but ElliotMade suggests it could be developed into a wearable, or a non-magnetic display to communicate with patients in an MRI scanner, keeping the electronics well out of the way.