This Project Takes Laser Harps to a Whole New Level

What could be better than a harp? A laser harp, of course — and Jonathan Bumstead has created one that forgoes the vertically-facing strings/lasers for a horizontal orientation, in very sci-fi looking box structure. The device features six rows of lasers, plus corresponding photoresistor receivers. Two pairs per each row are implemented for 12 total notes.

To wrap around the entirety of the structure, each of the 12 beams are pointed at an adjacent corner. Each uses a mirror to reflect the laser 90 degrees to hit its photoresistor positioned on the next corner section.

Along with the novel laser interface, the harp features a potentiometer for volume control, and a rotary switch that can cycle between 16 instruments. The instrument-in-use is displayed mechanically on a front panel, via a stepper that rotates the proper label into place. It’s equipped with internal speakers, as well as an audio jack for either private listening or to pump sounds tunes to an even more powerful device.

Everything is controlled by an Arduino Mega, with lasers turned on and off through digital outputs, and the photoresistor thresholds sensed via analog pins. Sound itself is produced with the help of an Adafruit Music Maker shield. It’s a really nice build, and you can see it in use the video above!