集(ji)(ji)電(dian)(dian)器從字(zi)面上理解，這就是(shi)收集(ji)(ji)器。在電(dian)(dian)子(zi)器件內(nei)，有時(shi)把用來收集(ji)(ji)電(dian)(dian)子(zi)的(de)(de)(de)電(dian)(dian)極(ji)(ji)，例(li)如受電(dian)(dian)子(zi)束所投射(she)的(de)(de)(de)電(dian)(dian)極(ji)(ji)叫做集(ji)(ji)電(dian)(dian)器（即(ji)集(ji)(ji)電(dian)(dian)極(ji)(ji)）。在發電(dian)(dian)機(ji)內(nei)，則是(shi)將用來把電(dian)(dian)機(ji)內(nei)所產生(sheng)的(de)(de)(de)交變電(dian)(dian)流轉換為脈動電(dian)(dian)流，即(ji)變成(cheng)方向恒定而大(da)小(xiao)在變化(hua)著(zhu)的(de)(de)(de)電(dian)(dian)流的(de)(de)(de)裝置(zhi)叫做集(ji)(ji)電(dian)(dian)器。