偏振(zhen)光，英文(wen)名：Polarization（偏極(ji)化）

偏(pian)(pian)(pian)振(zhen)(zhen)光在光學元器(qi)件中應用產品有：偏(pian)(pian)(pian)光片(pian)，線偏(pian)(pian)(pian)光，圓(yuan)偏(pian)(pian)(pian)光，偏(pian)(pian)(pian)振(zhen)(zhen)鏡(jing)，偏(pian)(pian)(pian)振(zhen)(zhen)分束鏡(jing)，起偏(pian)(pian)(pian)器(qi)，檢偏(pian)(pian)(pian)器(qi)，保偏(pian)(pian)(pian)器(qi)，偏(pian)(pian)(pian)振(zhen)(zhen)分束膠合棱鏡(jing)，法拉遞旋(xuan)轉(zhuan)片(pian)，旋(xuan)光片(pian)，渦旋(xuan)波片(pian)，單反相機鏡(jing)頭CPL濾鏡(jing)，激光器(qi)旋(xuan)光器(qi)。

自然光(guang)(guang)(guang)，太陽光(guang)(guang)(guang)，普通(tong)光(guang)(guang)(guang)源(yuan)(yuan)，面光(guang)(guang)(guang)源(yuan)(yuan)，OLED，LED燈光(guang)(guang)(guang)叫非(fei)偏(pian)振光(guang)(guang)(guang)

太陽(yang)鏡(jing)眼，AR/VR眼鏡(jing)，CCD，COMS，LCD屏(ping)，光(guang)柵，具體偏振(zhen)光(guang)的綜(zong)合物。常(chang)(chang)常(chang)(chang)把綜(zong)合光(guang)：U=P+S在光(guang)學薄(bo)膜設計(ji)中(zhong)U=Tp+Ts或(Rp+Rs)，T為透過(guo)，R為反(fan)射；矢量(liang)(liang)分為P分量(liang)(liang)（Paralled水平或平行偏振(zhen))和S分量(liang)(liang)(Senkrcht垂直偏振(zhen)）。

自然光

光(guang)(guang)(guang)(guang)(guang)波(bo)是(shi)(shi)橫波(bo)，即(ji)光(guang)(guang)(guang)(guang)(guang)波(bo)矢量的(de)振(zhen)動方(fang)向(xiang)垂直于(yu)光(guang)(guang)(guang)(guang)(guang)的(de)傳播方(fang)向(xiang)。通常，光(guang)(guang)(guang)(guang)(guang)源(yuan)發出(chu)的(de)光(guang)(guang)(guang)(guang)(guang)波(bo)，其光(guang)(guang)(guang)(guang)(guang)波(bo)矢量的(de)振(zhen)動在(zai)垂直于(yu)光(guang)(guang)(guang)(guang)(guang)的(de)傳播方(fang)向(xiang)上作無規則取(qu)向(xiang)，在(zai)空(kong)間內，光(guang)(guang)(guang)(guang)(guang)波(bo)矢量的(de)分布可(ke)看(kan)作是(shi)(shi)機會均等(deng)的(de)，它們的(de)總(zong)和與光(guang)(guang)(guang)(guang)(guang)的(de)傳播方(fang)向(xiang)是(shi)(shi)對稱的(de)，即(ji)光(guang)(guang)(guang)(guang)(guang)矢量具有(you)軸對稱性、均勻分布、各(ge)方(fang)向(xiang)振(zhen)動的(de)振(zhen)幅相同，這(zhe)種光(guang)(guang)(guang)(guang)(guang)就稱為自(zi)然(ran)光(guang)(guang)(guang)(guang)(guang)。（即(ji)光(guang)(guang)(guang)(guang)(guang)是(shi)(shi)散亂(luan)無序的(de)，自(zi)由派）。

線偏振光

光(guang)矢量端點(dian)穿越軌(gui)跡為直線(xian)(xian)，即(ji)光(guang)矢量只沿著一個確定的(de)方(fang)向(xiang)振動，其大(da)小隨相位變化、方(fang)向(xiang)不變，稱為線(xian)(xian)偏振光(guang)。最大(da)特點(dian)是雙向(xiang)性(xing)偏振。

橢圓偏振光

光(guang)(guang)矢(shi)量端點穿越軌跡(ji)為(wei)一(yi)橢圓(yuan)，即(ji)光(guang)(guang)矢(shi)量不斷(duan)旋轉，其大小(xiao)、方向隨(sui)時間有規律的變化。像(xiang)電力不穩一(yi)樣，忽(hu)明忽(hu)暗，一(yi)會(hui)兒(er)P光(guang)(guang)，一(yi)會(hui)兒(er)S光(guang)(guang)受(shou)脈沖影響還(huan)不穩，形成近視(shi)的橢圓(yuan)。

圓偏振光

光(guang)(guang)(guang)矢量端點(dian)穿越軌跡為(wei)一(yi)圓，即光(guang)(guang)(guang)矢量不斷旋轉，其大小不變，但方向隨時間有(you)(you)規律地變化(hua)。部分(fen)偏(pian)(pian)振(zhen)光(guang)(guang)(guang)，像個正弦(xian)波(bo)有(you)(you)周期性翻滾(gun)，最大特(te)點(dian)是：單向性偏(pian)(pian)振(zhen)。偏(pian)(pian)振(zhen)片(pian)用途最廣的(de)就是用于LCD的(de)液晶顯示屏中。所以，拿(na)一(yi)片(pian)祼的(de)偏(pian)(pian)振(zhen)片(pian)對(dui)著顯示器(qi)水(shui)平或(huo)垂直或(huo)轉某個角度，會發現顯示器(qi)上(shang)(shang)的(de)圖案由黑(hei)變亮或(huo)由亮變黑(hei)，把該偏(pian)(pian)振(zhen)片(pian)正反(fan)面去測試都(dou)相(xiang)同，這就是線偏(pian)(pian)振(zhen)片(pian)（都(dou)叫線偏(pian)(pian)光(guang)(guang)(guang)），反(fan)之只有(you)(you)一(yi)個面差別(bie)大，反(fan)面差別(bie)不大就是圓偏(pian)(pian)振(zhen)片(pian)（都(dou)叫圓偏(pian)(pian)光(guang)(guang)(guang)）。市面上(shang)(shang)的(de)圓偏(pian)(pian)振(zhen)片(pian)原理就是，加了一(yi)片(pian)1/4λ的(de)波(bo)片(pian)。

什么叫波片?

波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)，又稱為(wei)(wei)(wei)相(xiang)位延遲片(pian)(pian)(pian)(pian)(pian)，因為(wei)(wei)(wei)偏(pian)振(zhen)(zhen)(zhen)(zhen)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)具(ju)(ju)有(you)折(zhe)射(she)(she)率不(bu)同(tong)，可能(neng)用(yong)薄膜定向(xiang)(xiang)拉伸或(huo)雙(shuang)折(zhe)射(she)(she)材料加工而(er)成。使通過(guo)波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)的(de)兩(liang)個(ge)互(hu)相(xiang)正(zheng)交的(de)偏(pian)振(zhen)(zhen)(zhen)(zhen)分量產(chan)生相(xiang)位偏(pian)移，可用(yong)來調整光(guang)(guang)(guang)(guang)(guang)(guang)(guang)束(shu)的(de)偏(pian)振(zhen)(zhen)(zhen)(zhen)狀態。在(zai)(zai)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)學元器件中常見(jian)的(de)波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)由石英(ying)晶體(ti)制(zhi)作而(er)成，主要(yao)為(wei)(wei)(wei)四(si)分之(zhi)(zhi)(zhi)一(yi)波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)和二分之(zhi)(zhi)(zhi)一(yi)波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)（半波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)）。石英(ying)晶體(ti)（也叫人工水晶或(huo)人造晶體(ti)）具(ju)(ju)有(you)雙(shuang)折(zhe)射(she)(she)率效應，依據X,Y,Z三(san)軸(zhou)方(fang)(fang)向(xiang)(xiang)上(shang)，定向(xiang)(xiang)切割的(de)角度(du)不(bu)同(tong)，產(chan)生的(de)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)程差不(bu)同(tong)。四(si)分之(zhi)(zhi)(zhi)一(yi)波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)（λ/4波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)）：能(neng)使o光(guang)(guang)(guang)(guang)(guang)(guang)(guang)和e光(guang)(guang)(guang)(guang)(guang)(guang)(guang)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)程差為(wei)(wei)(wei)λ/4的(de)晶片(pian)(pian)(pian)(pian)(pian)。旋轉波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)使入(ru)射(she)(she)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)偏(pian)振(zhen)(zhen)(zhen)(zhen)方(fang)(fang)向(xiang)(xiang)與波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)兩(liang)軸(zhou)夾角為(wei)(wei)(wei)45°，橢圓/圓偏(pian)振(zhen)(zhen)(zhen)(zhen)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)經過(guo)四(si)分之(zhi)(zhi)(zhi)一(yi)波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)后，變(bian)成了線偏(pian)振(zhen)(zhen)(zhen)(zhen)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)。同(tong)理，如(ru)果(guo)入(ru)射(she)(she)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)偏(pian)振(zhen)(zhen)(zhen)(zhen)方(fang)(fang)向(xiang)(xiang)與波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)兩(liang)軸(zhou)夾角為(wei)(wei)(wei)45°，線偏(pian)振(zhen)(zhen)(zhen)(zhen)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)經過(guo)四(si)分之(zhi)(zhi)(zhi)一(yi)波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)后，變(bian)成了圓偏(pian)振(zhen)(zhen)(zhen)(zhen)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)。波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)（或(huo)延遲板）是具(ju)(ju)有(you)特定雙(shuang)折(zhe)射(she)(she)的(de)透(tou)明片(pian)(pian)(pian)(pian)(pian)，通常用(yong)來控制(zhi)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)束(shu)的(de)偏(pian)振(zhen)(zhen)(zhen)(zhen)態。波(bo)(bo)(bo)片(pian)(pian)(pian)(pian)(pian)具(ju)(ju)有(you)一(yi)個(ge)快軸(zhou)和一(yi)個(ge)慢(man)軸(zhou)，都是垂(chui)直(zhi)(zhi)于表面和光(guang)(guang)(guang)(guang)(guang)(guang)(guang)束(shu)傳播方(fang)(fang)向(xiang)(xiang)的(de)，并且相(xiang)互(hu)垂(chui)直(zhi)(zhi)。在(zai)(zai)快軸(zhou)方(fang)(fang)向(xiang)(xiang)偏(pian)振(zhen)(zhen)(zhen)(zhen)的(de)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)相(xiang)速度(du)稍大。需要(yao)的(de)光(guang)(guang)(guang)(guang)(guang)(guang)(guang)延遲（兩(liang)偏(pian)振(zhen)(zhen)(zhen)(zhen)方(fang)(fang)向(xiang)(xiang)上(shang)的(de)相(xiang)位延遲差）只(zhi)在(zai)(zai)有(you)限波(bo)(bo)(bo)長區(qu)域(yu)和有(you)限入(ru)射(she)(she)角范圍內(nei)能(neng)夠得(de)到。 

種類和應用

最常見(jian)的波片(pian)(pian)是(shi)四分(fen)之一波片(pian)(pian)（λ/4 片(pian)(pian)）和半(ban)波片(pian)(pian)（λ/2片(pian)(pian)），其(qi)中兩(liang)線偏(pian)振(zhen)方向的相位(wei)延(yan)遲(chi)差分(fen)別為 π/2和π，對(dui)應的相位(wei)傳播(bo)距離分(fen)別為λ / 4和λ / 2。 

如果光束為(wei)線偏(pian)振的，并且偏(pian)振方向(xiang)是(shi)沿(yan)著(zhu)波片的某一個軸，那么(me)偏(pian)振方向(xiang)不改(gai)變。 

如果入射的(de)偏(pian)(pian)振(zhen)(zhen)態與任一(yi)軸不重合，波(bo)片為半波(bo)片，那么(me)偏(pian)(pian)振(zhen)(zhen)光仍然是線偏(pian)(pian)振(zhen)(zhen)的(de)，但(dan)是偏(pian)(pian)振(zhen)(zhen)方向(xiang)發(fa)生旋(xuan)轉。如果線偏(pian)(pian)振(zhen)(zhen)光與軸夾角為 45°，那么(me)偏(pian)(pian)振(zhen)(zhen)方向(xiang)旋(xuan)轉90°。 

 如果入射線偏(pian)(pian)(pian)振(zhen)(zhen)光(guang)(guang)與軸(zhou)之(zhi)間夾角為 45°，通過四(si)分之(zhi)一(yi)波(bo)片可(ke)以得到圓(yuan)(yuan)偏(pian)(pian)(pian)振(zhen)(zhen)光(guang)(guang)。（其它的線偏(pian)(pian)(pian)振(zhen)(zhen)光(guang)(guang)會變成橢(tuo)圓(yuan)(yuan)偏(pian)(pian)(pian)振(zhen)(zhen)光(guang)(guang)。）反過來，圓(yuan)(yuan)偏(pian)(pian)(pian)振(zhen)(zhen)光(guang)(guang)通過四(si)分之(zhi)一(yi)波(bo)片可(ke)以得到線偏(pian)(pian)(pian)振(zhen)(zhen)光(guang)(guang)。 

在(zai)(zai)激光(guang)器諧(xie)振腔中，在(zai)(zai)增(zeng)益介質兩邊放(fang)置兩個(ge)四分之一波(bo)(bo)片(pian)可以(yi)(yi)實(shi)現單頻工作（參閱扭(niu)曲模技術）。在(zai)(zai)激光(guang)晶體和(he)諧(xie)振腔反射鏡(jing)之間放(fang)置一個(ge)半波(bo)(bo)片(pian)可以(yi)(yi)減小去極化損耗。半波(bo)(bo)片(pian)和(he)偏(pian)振片(pian)結合(he)使用可以(yi)(yi)實(shi)現可調透射率(lv)的輸出耦合(he)器。 

波片(pian)通常由石(shi)英晶體（SiO2）制作，因為它(ta)在很大的波長(chang)范圍內(nei)具有(you)(you)很高的透明度，并且具有(you)(you)很高的光學(xue)質量。還有(you)(you)一些其它(ta)的材(cai)料（應用(yong)于其它(ta)波長(chang)范圍）可(ke)以，例如方解(jie)石(shi)（CaCO3），氟(fu)化鎂（MgF2），藍寶石(shi)（Al2O3），云母(mu)（一種二(er)氧化硅(gui)材(cai)料）和一些雙折(zhe)射聚合(he)物。 

（來源：網絡，版權歸(gui)原(yuan)作者(zhe)，若有侵權請聯系(xi)刪除）