在人眼内虹膜瞳孔后,有一个双凸面的透明体,我们称它为晶体状(简称晶体)。晶体就像照像机里的镜头,起着重要的屈折光线的作用。它还通过位于睫状体内的睫状肌的松驰与收缩、晶体悬韧带被拉紧与放松而随之变薄与变厚,对于自动调节眼睛的看远看近能力,具有很大作用。当晶体失去其正常透明性,呈局灶性或弥漫性混浊,光线通过受到阻碍而影响视力时,即成为白内障。白内障包括遗传性、先天性、代谢性、外伤性、中毒性和老年性等类型。老年性白内障的 In the human eye iris pupil, there is a biconvex transparent body, we call it crystal (referred to as the crystal). The crystal is like a camera lens, plays an important role in the refractive light. It also through the ciliary body in the ciliary body relaxation and contraction, the crystal suspensory ligament is tightened and relaxed with the accompanying thinning and thickening, the automatic adjustment of the eyes look far and near ability to play a great role. When the crystal loses its normal transparency, was focal or diffuse opacity, light is blocked and affect vision, which becomes cataracts. Cataracts include genetic, congenital, metabolic, traumatic, toxic and senile types. Senile cataract