一、光耦的作用是什么

光耦是(shi)光電(dian)(dian)耦合(he)(he)器(qi)的簡(jian)稱，又叫光耦合(he)(he)器(qi)，是(shi)以(yi)光為(wei)媒介傳(chuan)輸(shu)電(dian)(dian)信(xin)(xin)號(hao)的一種電(dian)(dian)一光一電(dian)(dian)轉換器(qi)件，它通過發光二極管(guan)（LED）、受(shou)控光源或激光作(zuo)(zuo)為(wei)光源，將輸(shu)入(ru)的電(dian)(dian)信(xin)(xin)號(hao)轉換成光信(xin)(xin)號(hao)輸(shu)出(chu)，以(yi)實現電(dian)(dian)信(xin)(xin)號(hao)的調制與轉換，其主要作(zuo)(zuo)用有(you)：1、有(you)效隔離(li)電(dian)(dian)氣(qi)上的輸(shu)入(ru)和(he)輸(shu)出(chu)電(dian)(dian)路。2、使信(xin)(xin)號(hao)可以(yi)以(yi)光的形式傳(chuan)輸(shu)，具有(you)良好的抗干擾效果。3、起保護作(zuo)(zuo)用，當光耦合(he)(he)器(qi)的輸(shu)入(ru)側(ce)受(shou)到強(qiang)電(dian)(dian)壓沖擊而損壞時，由于光耦合(he)(he)器(qi)的隔離(li)作(zuo)(zuo)用，不會損壞輸(shu)出(chu)側(ce)電(dian)(dian)路。

二、光耦工作原理是什么

光(guang)(guang)(guang)耦合器(qi)(qi)(qi)一(yi)般由光(guang)(guang)(guang)的(de)(de)發(fa)(fa)射部分（發(fa)(fa)光(guang)(guang)(guang)器(qi)(qi)(qi)件(jian)(jian)）、接收(shou)部分（光(guang)(guang)(guang)敏(min)器(qi)(qi)(qi)件(jian)(jian)）以(yi)(yi)及信號(hao)放(fang)大(da)部分（電(dian)(dian)(dian)子(zi)電(dian)(dian)(dian)路(lu)）三部分組成，其工作原理是：以(yi)(yi)發(fa)(fa)光(guang)(guang)(guang)器(qi)(qi)(qi)件(jian)(jian)的(de)(de)管(guan)腳(jiao)為輸(shu)入(ru)端，光(guang)(guang)(guang)敏(min)器(qi)(qi)(qi)件(jian)(jian)的(de)(de)管(guan)腳(jiao)為輸(shu)出端，工作時把電(dian)(dian)(dian)信號(hao)加到輸(shu)入(ru)端，使(shi)發(fa)(fa)光(guang)(guang)(guang)器(qi)(qi)(qi)件(jian)(jian)的(de)(de)芯體發(fa)(fa)光(guang)(guang)(guang)，而光(guang)(guang)(guang)敏(min)器(qi)(qi)(qi)件(jian)(jian)受光(guang)(guang)(guang)照后(hou)產(chan)生光(guang)(guang)(guang)電(dian)(dian)(dian)流并經(jing)電(dian)(dian)(dian)子(zi)電(dian)(dian)(dian)路(lu)放(fang)大(da)后(hou)輸(shu)出，實現電(dian)(dian)(dian)→光(guang)(guang)(guang)→電(dian)(dian)(dian)的(de)(de)轉(zhuan)換(huan)，從而起到輸(shu)入(ru)、輸(shu)出、隔離的(de)(de)作用。簡(jian)單(dan)來說，就(jiu)是輸(shu)入(ru)的(de)(de)電(dian)(dian)(dian)信號(hao)驅動發(fa)(fa)光(guang)(guang)(guang)二極管(guan)，使(shi)之發(fa)(fa)出一(yi)定波長的(de)(de)光(guang)(guang)(guang)，被光(guang)(guang)(guang)探測器(qi)(qi)(qi)接收(shou)而產(chan)生光(guang)(guang)(guang)電(dian)(dian)(dian)流，再經(jing)過(guo)進(jin)一(yi)步放(fang)大(da)后(hou)輸(shu)出，這就(jiu)完成了電(dian)(dian)(dian)→光(guang)(guang)(guang)→電(dian)(dian)(dian)的(de)(de)轉(zhuan)換(huan)。

三、光耦怎么測好壞

光耦的好壞判斷，一般可以通過在路測量其內部二極管和三極管的正反向電阻來確定，如果想獲得更可靠的檢測結果，可以采取下面三種檢測方法：1、比較法：拆下懷疑有問題的光耦，用萬用表測量其內部二極管、三極管的正反向電阻值，用其與好的光耦對應腳的測量值進行比較，若阻值相差較大，則說明光耦已損壞。2、數字萬用表檢測法：將光耦內接二極管的＋端{1}腳和－端{2}腳分別插入數字萬用表的Hfe 的c、e插孔內，此時數字萬用表應置于NPN擋；然后將光耦內接光電三極管C極{5}腳接指針式萬用表的黑表筆，e極{4}腳接紅表筆，并將指針式萬用表撥在RX1k擋。這樣就能通過指針式萬用表指針的偏轉角度——實際上是光電流的變化，來判斷光耦的情況。指針向右偏轉角度越大，說明光耦的光電轉換效率越高，即傳輸比越高，反之越低；若表針不動，則說明光耦已損壞。3、光電效應判斷法：將萬用表置于RX1k電阻擋，兩表筆分別接在光耦的輸出端{4}、{5}腳；然后用一節1．5V的電池與一只50～100Ω的電阻串接后，電池的正極端接EL817的{1}腳，負極端碰接{2}腳，或者正極端碰接{1}腳，負極端接{2}腳，這時觀察接在輸出端萬用表的指針偏轉情況。如果指針擺動，說明光耦是好的，如果不擺動，則說明光耦已損壞。萬用表指針擺動偏轉角度越大，表明光電轉換靈敏度越高。損壞的光耦需要及時更換，如果您需要采購光耦，可以先來了解一下光耦十大品牌。

四、光耦隔離是什么意思

光(guang)(guang)耦是(shi)(shi)光(guang)(guang)電(dian)(dian)(dian)耦合器，用(yong)于(yu)(yu)實現(xian)光(guang)(guang)電(dian)(dian)(dian)轉換，光(guang)(guang)耦隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)，顧名思(si)義就(jiu)是(shi)(shi)利(li)用(yong)光(guang)(guang)耦合器進(jin)(jin)行隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)，常用(yong)于(yu)(yu)信號隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)或光(guang)(guang)電(dian)(dian)(dian)的(de)(de)(de)隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)。光(guang)(guang)耦隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)的(de)(de)(de)作(zuo)(zuo)用(yong)主要(yao)有(you)兩點(dian)：1、隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)作(zuo)(zuo)用(yong)：光(guang)(guang)耦可(ke)(ke)以起(qi)到信號的(de)(de)(de)隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)作(zuo)(zuo)用(yong)，因(yin)此光(guang)(guang)耦隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)傳輸出來(lai)的(de)(de)(de)信號有(you)著單向傳輸的(de)(de)(de)特點(dian)，因(yin)此可(ke)(ke)以實現(xian)信號的(de)(de)(de)單向傳輸，從(cong)而(er)使得輸入端以及輸出端實現(xian)了電(dian)(dian)(dian)氣隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)。輸出線(xian)號對于(yu)(yu)輸入端不會產(chan)生影響，抗(kang)(kang)干擾(rao)(rao)的(de)(de)(de)能(neng)力(li)強(qiang)，并且工作(zuo)(zuo)穩定。2、電(dian)(dian)(dian)平轉換作(zuo)(zuo)用(yong)：光(guang)(guang)耦隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)還(huan)可(ke)(ke)以實現(xian)電(dian)(dian)(dian)平的(de)(de)(de)轉換作(zuo)(zuo)用(yong)。就(jiu)好比單片機(ji)是(shi)(shi)采用(yong)3.3伏進(jin)(jin)行供電(dian)(dian)(dian)的(de)(de)(de)，那么(me)我們(men)就(jiu)需要(yao)輸出5伏電(dian)(dian)(dian)壓(ya)的(de)(de)(de)方波，從(cong)而(er)確保光(guang)(guang)耦隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)起(qi)到了電(dian)(dian)(dian)平轉換作(zuo)(zuo)用(yong)。光(guang)(guang)耦隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)具有(you)占空比任意可(ke)(ke)調、隔(ge)(ge)(ge)(ge)離(li)(li)(li)(li)(li)耐壓(ya)高、抗(kang)(kang)干擾(rao)(rao)能(neng)力(li)強(qiang)、抗(kang)(kang)干擾(rao)(rao)能(neng)力(li)強(qiang)廣(guang)等(deng)優點(dian)，不過它同樣也存在(zai)傳輸延遲較(jiao)大、開關速度較(jiao)慢、成本較(jiao)高等(deng)缺(que)點(dian)。