The glass box of mosquitoes across the room is an old 10-gallon fish tank. Each time a beam strikes a bug, the computer makes a gunshot sound to signal a direct hit.
A novel audio beam loudspeaker which based on nonlinear propagation effects of ultrasonic in the air to generate audible sound with high directivity is presented.
提出了一种利用空气中超声波非线性传播效应制作的、可产生高指向性可听声的新型声束扬声器。
3
This first wireless telephone transmitted sound on a beamof light instead of electrical wires.