集(ji)(ji)電(dian)(dian)(dian)器(qi)從字面(mian)上理(li)解，這就(jiu)是收集(ji)(ji)器(qi)。在電(dian)(dian)(dian)子器(qi)件內(nei)，有(you)時把(ba)用(yong)來收集(ji)(ji)電(dian)(dian)(dian)子的(de)(de)電(dian)(dian)(dian)極，例如受電(dian)(dian)(dian)子束所(suo)投(tou)射的(de)(de)電(dian)(dian)(dian)極叫(jiao)做集(ji)(ji)電(dian)(dian)(dian)器(qi)（即(ji)集(ji)(ji)電(dian)(dian)(dian)極）。在發電(dian)(dian)(dian)機(ji)內(nei)，則是將用(yong)來把(ba)電(dian)(dian)(dian)機(ji)內(nei)所(suo)產生的(de)(de)交(jiao)變(bian)電(dian)(dian)(dian)流(liu)轉換為脈動(dong)電(dian)(dian)(dian)流(liu)，即(ji)變(bian)成方(fang)向恒定而大小(xiao)在變(bian)化著的(de)(de)電(dian)(dian)(dian)流(liu)的(de)(de)裝(zhuang)置叫(jiao)做集(ji)(ji)電(dian)(dian)(dian)器(qi)。