Abstract: The sound standing wave experiment is a compulsory part of university physics experiments, but its traditional experimental apparatus is inadequate. The article provides an in -depth analysis of the mechanism and characteristics of sound standing wave generation. We have designed an acoustic-optical conversion circuit, which can effectively and precisely convert the sound standing wave signal into a diode luminescence signal and apply it in a standing wave tube, and we have successfully developed a sound-controlled light-emitting standing wave experimental apparatus. The apparatus not only realizes the organic combination of qualitative demonstration and quantitative measurement of the standing wave phenomenon, but also has the advantages of easy operation, visual clarity, stable operation, and high measurement accuracy. It can also provide important reference for the development of similar experimental teaching apparatus in universities.

Key words: sound-controlled light-emitting, circuit design, standing wave, application