一、光電開關是模擬量還是數字量

光(guang)電(dian)開關(guan)的信(xin)號通常為數字量。

由于(yu)光(guang)電開關(guan)的(de)(de)(de)輸(shu)(shu)(shu)出(chu)信號(hao)(hao)(hao)往往只有兩種情況，即有光(guang)和(he)斷(duan)光(guang)。因(yin)此，受到檢(jian)測物體(ti)大小、光(guang)源亮(liang)度(du)、反射度(du)等(deng)因(yin)素(su)的(de)(de)(de)影(ying)響，無法保證模擬量的(de)(de)(de)穩(wen)定(ding)性和(he)準確性。相比之下，數(shu)(shu)(shu)字量信號(hao)(hao)(hao)不受這些因(yin)素(su)的(de)(de)(de)影(ying)響，根據輸(shu)(shu)(shu)出(chu)的(de)(de)(de)電壓或(huo)電流值是否超過設定(ding)門檻(jian)，輸(shu)(shu)(shu)出(chu)0或(huo)1的(de)(de)(de)數(shu)(shu)(shu)字信號(hao)(hao)(hao)更加(jia)穩(wen)定(ding)、準確，且(qie)易于(yu)處理和(he)傳輸(shu)(shu)(shu)，因(yin)此光(guang)電開關(guan)通常輸(shu)(shu)(shu)出(chu)數(shu)(shu)(shu)字量信號(hao)(hao)(hao)。

二、光電開關是直流還是交流

光電開關的供電可以是直(zhi)流(liu)也可以是交流(liu)。

光電(dian)(dian)(dian)(dian)開(kai)關(guan)的(de)供(gong)電(dian)(dian)(dian)(dian)種(zhong)類包括直(zhi)(zhi)(zhi)流(liu)(liu)(liu)式(shi)、交(jiao)(jiao)流(liu)(liu)(liu)式(shi)和直(zhi)(zhi)(zhi)流(liu)(liu)(liu)交(jiao)(jiao)流(liu)(liu)(liu)混合式(shi)三種(zhong)。直(zhi)(zhi)(zhi)流(liu)(liu)(liu)式(shi)光電(dian)(dian)(dian)(dian)開(kai)關(guan)采用直(zhi)(zhi)(zhi)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)供(gong)電(dian)(dian)(dian)(dian)，電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)范(fan)圍一般為(wei)12-24V（10-30V）的(de)直(zhi)(zhi)(zhi)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)。交(jiao)(jiao)流(liu)(liu)(liu)式(shi)光電(dian)(dian)(dian)(dian)開(kai)關(guan)則(ze)采用交(jiao)(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)供(gong)電(dian)(dian)(dian)(dian)，電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)范(fan)圍為(wei)90-240V交(jiao)(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)，適用于(yu)110VAC與220VAC場合的(de)供(gong)電(dian)(dian)(dian)(dian)。而直(zhi)(zhi)(zhi)流(liu)(liu)(liu)交(jiao)(jiao)流(liu)(liu)(liu)混合式(shi)光電(dian)(dian)(dian)(dian)開(kai)關(guan)則(ze)允許(xu)直(zhi)(zhi)(zhi)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)與交(jiao)(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)都可(ke)以直(zhi)(zhi)(zhi)接接入(ru)同一個供(gong)電(dian)(dian)(dian)(dian)回路(lu)，直(zhi)(zhi)(zhi)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)范(fan)圍為(wei)12-240V，交(jiao)(jiao)流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)范(fan)圍為(wei)24-240V，這種(zhong)形式(shi)具有較高的(de)適應性，不需要考慮配電(dian)(dian)(dian)(dian)的(de)問題(ti)。

因此，光(guang)電(dian)開關的(de)供電(dian)方式(shi)既(ji)可以是(shi)直(zhi)流(liu)也可以是(shi)交(jiao)流(liu)，具體取決于其(qi)設計時(shi)所采用的(de)供電(dian)形式(shi)。

三、光電開關是有源還是無源

光電開關既有(you)有(you)源型，也有(you)無(wu)源型。

1、有源型光電開關：需要另外提供一個電源或信(xin)號源才能驅動它的工(gong)作。例(li)如，光電耦合器(qi)、光電轉換器(qi)等。

2、無源型光電開關：不需要外部電源或(huo)信(xin)號(hao)源，它可以直接(jie)將光信(xin)號(hao)轉換成電信(xin)號(hao)輸出(chu)。例(li)如，光電二極(ji)管、光敏三極(ji)管等。

需要注意的是，無源型光電開關需要有較高的光照強(qiang)度才能(neng)工作，因此其檢測距離一般比有源型的短。