The US Military Is Making Lasers That Create Voices out of Thin Air

defenseone.com ^

[DiogenesLamp]

I remember back in the 70’s when I sold hi-fi there were articles about attempting to produce sound “in thin air” without a physical driver.

I figured out how to do that in theory several decades ago. Heterodyning two High frequency audio signals (above the range of human hearing) with a differential frequency of what you want the sound to be.

Focus the two sources at a point in space, and you can create compressions and rarefactions that correspond to the audio signal you wish to reproduce.

I've read that people have actually done this, and I pat myself on the back for having thought of how to do it in theory back in the 1980s.

But doing it with light will give you a far greater range, because you have more control with light than you would with high frequency audio signals.

[daniel1212]

Like rail guns and hypersonic vehicles which should have been kept secret (if that is still possible) rather than advertised to incite Putin and the Chinese to develop the same, this also, if of any significance, should not be reported on.