They basically bounce the sound waves off a parabolic mirror, so that they come from multiple directions but converge on one spot. The spot where they converge is the only place where the sound waves are strong enough to cause cavitation.
This is actually a fairly mature technology that has been used to treat kidney stones for decades (lithotripsy).
They basically bounce the sound waves off a parabolic mirror, so that they come from multiple directions but converge on one spot. The spot where they converge is the only place where the sound waves are strong enough to cause cavitation.
This is actually a fairly mature technology that has been used to treat kidney stones for decades (lithotripsy).