人到了一定年龄,看远清楚,看近物模糊的现象,被称为老花眼,医学上称为老年性近视。老年人眼的变化,主要是出现老人环、老花眼、老年性白内障及眼睑下垂等。眼球好比一台灵巧的照相机,角膜好似照相机的镜头,瞳孔相当于光圈,整个眼球就象一个暗箱,视网膜好比底片,眼睛里的睫状肌及晶状体组成的自动“对光”设备则用来调节 People to a certain age, look far clear to see the phenomenon of near-blurry, known as presbyopia, medically known as senile myopia. Changes in the elderly eye, the main ring appears elderly, presbyopia, senile cataracts and ptosis and so on. The eyeball is like a smart camera. The cornea looks like a camera lens. The pupil is equivalent to the iris. The entire eye is like a black box. The retina is like an automatic “light ” device composed of the ciliary muscle and lens in the eye. To adjust