偏光鏡是根據光線的偏振原理制造。是利用偏振光的特性，以偏振鏡片把非金屬物體、水面等反光過濾消除的透鏡。偏振鏡可以消除反光及使色彩更鮮艷，一些電影甚至全片用偏振鏡拍攝，使畫面有更濃艷的色彩。當陽光投射在路面或水面上時，直接刺激眼睛，使眼睛感到眩目、疲勞、不能持久視物。特別是當您在駕駛汽車、進行戶外娛樂活動時，不僅影響我們的工作和娛樂情緒，甚至影響我們對物象的判斷力而造成危險；長期經受陽光的直接照射，還會導致視力的急速下降，形成近視、遠視、散光或白內障等。這時候偏光鏡的作用就體現了。

偏(pian)(pian)(pian)光(guang)(guang)(guang)(guang)(guang)(guang)鏡(jing)(jing)片是(shi)(shi)采用(yong)和隱形眼鏡(jing)(jing)一(yi)樣輕巧精密的(de)(de)(de)(de)(de)合成(cheng)樹脂制(zhi)成(cheng)，制(zhi)成(cheng)后，可(ke)濾去(qu)因水(shui)(shui)面(mian)潮濕或陽(yang)光(guang)(guang)(guang)(guang)(guang)(guang)照射下的(de)(de)(de)(de)(de)馬路(lu)反光(guang)(guang)(guang)(guang)(guang)(guang)。主要(yao)優點：輕，能濾去(qu)99%刺(ci)眼的(de)(de)(de)(de)(de)反射亂光(guang)(guang)(guang)(guang)(guang)(guang)，99%的(de)(de)(de)(de)(de)有害紫外(wai)光(guang)(guang)(guang)(guang)(guang)(guang)，不(bu)易碎。為了(le)過濾太(tai)(tai)陽(yang)照在水(shui)(shui)面(mian)、陸地或雪地上(shang)的(de)(de)(de)(de)(de)平等方向(xiang)的(de)(de)(de)(de)(de)刺(ci)眼光(guang)(guang)(guang)(guang)(guang)(guang)線(xian)，在鏡(jing)(jing)片上(shang)加(jia)入(ru)垂直(zhi)向(xiang)的(de)(de)(de)(de)(de)特(te)殊涂料，就稱為偏(pian)(pian)(pian)光(guang)(guang)(guang)(guang)(guang)(guang)鏡(jing)(jing)片。最適合戶(hu)外(wai)運動(dong)(dong)（例如：駕駛(shi)、海上(shang)活動(dong)(dong)、滑雪或釣魚）時使用(yong)。所(suo)以(yi)偏(pian)(pian)(pian)光(guang)(guang)(guang)(guang)(guang)(guang)太(tai)(tai)陽(yang)鏡(jing)(jing)可(ke)根據用(yong)途一(yi)般可(ke)以(yi)分為：滑雪鏡(jing)(jing)，釣魚鏡(jing)(jing)，偏(pian)(pian)(pian)光(guang)(guang)(guang)(guang)(guang)(guang)駕駛(shi)鏡(jing)(jing)，戶(hu)外(wai)運動(dong)(dong)鏡(jing)(jing)，高爾夫眼鏡(jing)(jing)。由于(yu)偏(pian)(pian)(pian)光(guang)(guang)(guang)(guang)(guang)(guang)太(tai)(tai)陽(yang)鏡(jing)(jing)的(de)(de)(de)(de)(de)首要(yao)功能是(shi)(shi)防紫外(wai)線(xian)和過濾偏(pian)(pian)(pian)振光(guang)(guang)(guang)(guang)(guang)(guang)，好的(de)(de)(de)(de)(de)偏(pian)(pian)(pian)光(guang)(guang)(guang)(guang)(guang)(guang)太(tai)(tai)陽(yang)鏡(jing)(jing)鏡(jing)(jing)片可(ke)以(yi)阻擋90%以(yi)上(shang)紫外(wai)線(xian)的(de)(de)(de)(de)(de)穿透，請選擇帶(dai)有“UV400”最佳(jia)阻隔(ge)紫外(wai)線(xian)標識的(de)(de)(de)(de)(de)偏(pian)(pian)(pian)光(guang)(guang)(guang)(guang)(guang)(guang)太(tai)(tai)陽(yang)鏡(jing)(jing)；如果佩戴了(le)不(bu)能阻擋紫外(wai)線(xian)和偏(pian)(pian)(pian)振濾光(guang)(guang)(guang)(guang)(guang)(guang)功能的(de)(de)(de)(de)(de)劣質偏(pian)(pian)(pian)光(guang)(guang)(guang)(guang)(guang)(guang)太(tai)(tai)陽(yang)鏡(jing)(jing)，比如深色的(de)(de)(de)(de)(de)太(tai)(tai)陽(yang)鏡(jing)(jing)，隨著(zhu)進(jin)入(ru)人(ren)(ren)眼的(de)(de)(de)(de)(de)光(guang)(guang)(guang)(guang)(guang)(guang)線(xian)變暗，人(ren)(ren)眼的(de)(de)(de)(de)(de)瞳(tong)孔(kong)會變大，則進(jin)入(ru)眼睛的(de)(de)(de)(de)(de)紫外(wai)線(xian)增(zeng)加(jia)，增(zeng)加(jia)對人(ren)(ren)眼的(de)(de)(de)(de)(de)傷害。