在(zai)空氣中傳(chuan)播(bo)(bo)的(de)(de)聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)波(bo)遇到聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)屏(ping)(ping)障時，就會產生反射、透射和繞射現象。一部(bu)分越過聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)屏(ping)(ping)障頂端(duan) 繞射到達受聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)點(dian)，一部(bu)分穿透聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)屏(ping)(ping)障到達受聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)點(dian)，一部(bu)分在(zai)聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)屏(ping)(ping)障壁面(mian)產生反射。聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)屏(ping)(ping)障的(de)(de)插入損失主要取(qu)決于聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)源發出的(de)(de)聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)波(bo)沿著三條道路(lu)傳(chuan)播(bo)(bo)的(de)(de)聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)能分配。聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)屏(ping)(ping)障的(de)(de)作用就是(shi)阻擋直達聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)的(de)(de)傳(chuan)播(bo)(bo)， 隔離透射聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)，并使繞射聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)有足(zu)夠的(de)(de)衰減。當聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)波(bo)撞(zhuang)擊到聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)屏(ping)(ping)障的(de)(de)壁面(mian)上時，會在(zai)聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)屏(ping)(ping)障邊緣產生繞射現象，而(er)在(zai)聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)屏(ping)(ping)障背后(hou)形成“聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)影(ying)區”。我們所期(qi)待的(de)(de)聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)屏(ping)(ping)障的(de)(de)減噪效(xiao)果就在(zai)“聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)影(ying)區”的(de)(de)范圍 內，這就是(shi)聲(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)(sheng)屏(ping)(ping)障降噪的(de)(de)基(ji)本原理。