紅(hong)外(wai)發光二極管是一(yi)種能發(fa)(fa)出紅外(wai)線的(de)(de)二極管(guan)(guan),通常(chang)應用于遙控(kong)器等場合。常(chang)用的(de)(de)紅外(wai)發(fa)(fa)光(guang)二極管(guan)(guan)其(qi)外(wai)形和發(fa)(fa)光(guang)二極管(guan)(guan)LED相似,發(fa)(fa)出紅外(wai)光(guang)。管(guan)(guan)壓降(jiang)約1.4v,工作電(dian)流一(yi)般(ban)小于20mA。為了適應不同(tong)的(de)(de)工作電(dian)壓,回(hui)路(lu)中(zhong)常(chang)常(chang)串有(you)限流電(dian)阻(zu)。
紅(hong)外(wai)線發光(guang)二極(ji)管由紅(hong)外(wai)輻射效率高的材料(常用(yong)砷化鎵GaAs)制成PN結,外(wai)加正向偏(pian)壓向PN結注入電(dian)流激發紅(hong)外(wai)光(guang)。光(guang)譜功(gong)率分布為(wei)(wei)中心波(bo)長(chang)(chang)830~950nm,半峰帶寬約40nm左右(you)。其最大的優點是可(ke)以完全無紅(hong)暴,(采用(yong)940~950nm波(bo)長(chang)(chang)紅(hong)外(wai)管)或僅有微弱紅(hong)暴(紅(hong)暴為(wei)(wei)有可(ke)見(jian)紅(hong)光(guang))而延(yan)長(chang)(chang)使用(yong)壽命。光(guang)是一(yi)種電(dian)磁波(bo),它的波(bo)長(chang)(chang)區間從幾個納米(mi)(mi)(1nm=10-9m)到1毫(hao)米(mi)(mi)(mm)左右(you)。人眼可(ke)見(jian)的只是其中一(yi)部分,我們稱其為(wei)(wei)可(ke)見(jian)光(guang),可(ke)見(jian)光(guang)的波(bo)長(chang)(chang)范圍為(wei)(wei)380nm~780nm,可(ke)見(jian)光(guang)波(bo)長(chang)(chang)由長(chang)(chang)到短分為(wei)(wei)紅(hong)、橙、黃、綠、青、蘭、紫(zi)(zi)光(guang),波(bo)長(chang)(chang)比紫(zi)(zi)光(guang)短的稱為(wei)(wei)紫(zi)(zi)外(wai)光(guang),波(bo)長(chang)(chang)比紅(hong)光(guang)長(chang)(chang)的稱為(wei)(wei)紅(hong)外(wai)光(guang)。