一、紅外濾光片是什么
紅外濾光片是一(yi)種(zhong)可(ke)以屏蔽(bi)紫外光(guang)(guang)(guang)、可(ke)見光(guang)(guang)(guang),僅(jin)透紅(hong)外光(guang)(guang)(guang)的(de)光(guang)(guang)(guang)學濾光(guang)(guang)(guang)片(pian)。在光(guang)(guang)(guang)學領域(yu)中紅(hong)外濾光(guang)(guang)(guang)片(pian)一(yi)般是由光(guang)(guang)(guang)學玻(bo)璃鍍膜、光(guang)(guang)(guang)學塑料(如PC及PMAA)或光(guang)(guang)(guang)學璃片(pian)再加入特種(zhong)染料做成的(de)有色玻(bo)璃濾光(guang)(guang)(guang)片(pian),上(shang)述工藝的(de)濾光(guang)(guang)(guang)片(pian)只能(neng)讓紅(hong)光(guang)(guang)(guang)通過(guo),宏(hong)觀上(shang)講都是紅(hong)外濾光(guang)(guang)(guang)片(pian)。
紅(hong)(hong)(hong)外(wai)濾光片主要應(ying)(ying)用于(yu)安防監控(kong)領域,紅(hong)(hong)(hong)外(wai)氣體分析儀,夜視產(chan)品(pin),紅(hong)(hong)(hong)外(wai)探測器,紅(hong)(hong)(hong)外(wai)接收機(ji),紅(hong)(hong)(hong)外(wai)感應(ying)(ying),紅(hong)(hong)(hong)外(wai)通訊產(chan)品(pin)。具體到產(chan)品(pin)比如:監控(kong)攝相(xiang)機(ji),遙(yao)控(kong)器,紅(hong)(hong)(hong)外(wai)幕墻產(chan)品(pin),紅(hong)(hong)(hong)外(wai)感應(ying)(ying)馬桶、水龍頭、洗手液裝置,紅(hong)(hong)(hong)外(wai)測溫器,紅(hong)(hong)(hong)外(wai)打印(yin)機(ji),交互(hu)式電子白板,紅(hong)(hong)(hong)外(wai)觸(chu)摸(mo)屏,指紋(wen)識別(bie)機(ji),人臉識別(bie)系(xi)統等(deng)。
二、紅外濾光片的分類
從(cong)材料上劃(hua)分,有光(guang)學玻(bo)(bo)璃鍍膜的,也有有色玻(bo)(bo)璃制成的,也有塑(su)料紅外(wai)濾光(guang)片(pian)。這里所指的是(shi)近紅外(wai)濾光(guang)片(pian)。如果(guo)涉(she)及到中遠(yuan)紅外(wai),材料還有Si,ZnSe,Sapphire,CaF2,石英(ying)玻(bo)(bo)璃等。
從光學特性上來劃分,有長波通型IR long pass filter和帶通型IR bandpass filter。其中長波通型(xing),包括以下幾種:
1、有色(se)(se)玻(bo)璃(li)制作而(er)成,通常為黑色(se)(se),比如(ru)IPG-800。它將可見光吸(xi)收,允許透過紅(hong)外(wai)光。如(ru)果(guo)透過此紅(hong)外(wai)濾(lv)光片(pian)去(qu)看太(tai)陽(yang),依然可以看見一個紅(hong)紅(hong)的太(tai)陽(yang)。適合用于紅(hong)外(wai)呈像。
2、在光(guang)(guang)學(xue)白(bai)玻(bo)璃(li)上通過真空鍍(du)膜(mo)制成紅外(wai)(wai)濾光(guang)(guang)片,比如IPGC-720,這種類型的(de)又叫光(guang)(guang)學(xue)冷鏡,它將可見光(guang)(guang)反射,讓紅外(wai)(wai)光(guang)(guang)透過。外(wai)(wai)觀看起來是(shi)(shi)銀色的(de),像是(shi)(shi)一面鏡子。如果是(shi)(shi)中遠紅外(wai)(wai)的(de)濾光(guang)(guang)片,要在Si,Sapphire,石英(ying)玻(bo)璃(li)上鍍(du)膜(mo)。
3、由特種塑(su)料制成的(de)紅外(wai)塑(su)料濾光(guang)片(pian),外(wai)觀黑(hei)色,如(ru)果透過(guo)此紅外(wai)濾光(guang)片(pian)去看太陽(yang),也(ye)可以(yi)(yi)看見(jian)一個紅紅的(de)太陽(yang)。這種塑(su)料的(de)材料可以(yi)(yi)是(shi)PC也(ye)可以(yi)(yi)是(shi)PMMA。
再說帶通型,帶通濾光片都(dou)是由真空鍍(du)(du)膜而成。對(dui)于近(jin)(jin)紅外的(de)(de)帶通來說,是在白玻璃上鍍(du)(du)膜。如(ru)果(guo)是中(zhong)遠紅外,則會在Sapphire上鍍(du)(du)膜。其中(zhong)近(jin)(jin)紅外的(de)(de)帶通濾光片相應的(de)(de)光源主(zhu)(zhu)要是紅外IR LED和紅外激(ji)光,所(suo)以主(zhu)(zhu)要波長(chang)有808nm,850nm,905nm,940nm,1064nm,也(ye)有不常(chang)用的(de)(de)780nm。所(suo)以常(chang)用的(de)(de)近(jin)(jin)紅外濾光片的(de)(de)波長(chang)主(zhu)(zhu)要就是這些。相應的(de)(de)型(xing)號有BPF-850,NBF-808,BPF-940。