laser harp
The laser harp is an instrument made up of several beams of laser light, each representing a different note. When a beam is blocked (or 'plucked', to further the harp analogy) the interruption is detected by a light-sensitive cell, and a corresponding MIDI note is transmitted to a synthesizer or sampled sound source. The instrument comes in framed or non-framed varieties and is visually dramatic. The most famous exponent of the laser harp is the French musician Jean-Michel Jarre.