在(zai)電(dian)(dian)子實踐技術過程中(zhong)，常常需要同時(shi)觀察兩種（或兩種以上）信號隨時(shi)間變化的過程。并對這些不同信號進行電(dian)(dian)

量(liang)的(de)測試和比較。為(wei)了達到這(zhe)個目的(de)，人們在(zai)應用(yong)普(pu)通示(shi)(shi)波(bo)(bo)(bo)器(qi)原理的(de)基礎上，采用(yong)了以下兩種(zhong)(zhong)同時顯示(shi)(shi)多(duo)(duo)個波(bo)(bo)(bo)形的(de)方(fang)法(fa)(fa)(fa)：一(yi)種(zhong)(zhong)是雙線（或(huo)多(duo)(duo)線）示(shi)(shi)波(bo)(bo)(bo)法(fa)(fa)(fa)；另(ling)一(yi)種(zhong)(zhong)是雙蹤(zong)（或(huo)多(duo)(duo)蹤(zong)）示(shi)(shi)波(bo)(bo)(bo)法(fa)(fa)(fa)。應用(yong)這(zhe)兩種(zhong)(zhong)方(fang)法(fa)(fa)(fa)制造出來的(de)示(shi)(shi)波(bo)(bo)(bo)器(qi)分別(bie)稱為(wei)雙線（或(huo)多(duo)(duo)線）示(shi)(shi)波(bo)(bo)(bo)器(qi)和雙蹤(zong)（或(huo)多(duo)(duo)蹤(zong)）示(shi)(shi)波(bo)(bo)(bo)器(qi)。

雙(shuang)(shuang)線（或多線）示(shi)(shi)波(bo)(bo)(bo)器是(shi)采用(yong)雙(shuang)(shuang)槍(qiang)(qiang)(qiang)（或多槍(qiang)(qiang)(qiang)）示(shi)(shi)波(bo)(bo)(bo)管(guan)(guan)來實(shi)現(xian)的(de)(de)(de)(de)。下(xia)(xia)(xia)面以(yi)雙(shuang)(shuang)槍(qiang)(qiang)(qiang)示(shi)(shi)波(bo)(bo)(bo)管(guan)(guan)為(wei)例加以(yi)簡單(dan)說明。雙(shuang)(shuang)槍(qiang)(qiang)(qiang)示(shi)(shi)波(bo)(bo)(bo)管(guan)(guan)有(you)兩(liang)個互(hu)相獨(du)(du)立(li)(li)的(de)(de)(de)(de)電(dian)(dian)子(zi)(zi)(zi)槍(qiang)(qiang)(qiang)產生兩(liang)束(shu)(shu)(shu)電(dian)(dian)子(zi)(zi)(zi)。另有(you)兩(liang)組互(hu)相獨(du)(du)立(li)(li)的(de)(de)(de)(de)偏轉系統(tong)，它們(men)各(ge)自(zi)控制一束(shu)(shu)(shu)電(dian)(dian)子(zi)(zi)(zi)作(zuo)上(shang)(shang)下(xia)(xia)(xia)、左右的(de)(de)(de)(de)運動。熒(ying)光屏是(shi)共(gong)用(yong)的(de)(de)(de)(de)，因而屏上(shang)(shang)可(ke)以(yi)同時顯示(shi)(shi)出兩(liang)種不(bu)同的(de)(de)(de)(de)電(dian)(dian)信號波(bo)(bo)(bo)形，雙(shuang)(shuang)線示(shi)(shi)波(bo)(bo)(bo)也可(ke)以(yi)采用(yong)單(dan)槍(qiang)(qiang)(qiang)雙(shuang)(shuang)線示(shi)(shi)波(bo)(bo)(bo)管(guan)(guan)來實(shi)現(xian)。這(zhe)種示(shi)(shi)波(bo)(bo)(bo)管(guan)(guan)只有(you)一個電(dian)(dian)子(zi)(zi)(zi)槍(qiang)(qiang)(qiang)，在(zai)工作(zuo)時是(shi)依(yi)靠特殊的(de)(de)(de)(de)電(dian)(dian)極把(ba)電(dian)(dian)子(zi)(zi)(zi)分成兩(liang)束(shu)(shu)(shu)。然后，由(you)管(guan)(guan)內的(de)(de)(de)(de)兩(liang)組互(hu)相獨(du)(du)立(li)(li)的(de)(de)(de)(de)偏轉系統(tong)，分別控制兩(liang)束(shu)(shu)(shu)電(dian)(dian)子(zi)(zi)(zi)上(shang)(shang)下(xia)(xia)(xia)、左右運動。熒(ying)光屏是(shi)共(gong)用(yong)的(de)(de)(de)(de)，能同時顯示(shi)(shi)出兩(liang)種不(bu)同的(de)(de)(de)(de)電(dian)(dian)信號波(bo)(bo)(bo)形。由(you)于雙(shuang)(shuang)線示(shi)(shi)波(bo)(bo)(bo)管(guan)(guan)的(de)(de)(de)(de)制造工藝(yi)要求高，成本(ben)也高，所以(yi)應用(yong)并不(bu)十(shi)分普遍。