This is the acorn from which the light-beam piano oak grew; the 1931 "Radio Trillion-Tone Piano", AKA the "Radio Organ of a Trillion Tones" invented by A. Lesti and F. Sammis of the USA.   It's a bit less elaborate than the light-beam piano and instead of glass disks with wave forms printed on them it used whirling slits spaced to produce different frequencies as a beam of light travelled through them to a photoelectric cell. 

It never really caught on, however.  That's probably because being capable of generating a trillion tones made practicing the scales a nightmare.

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