论文部分内容阅读
常听到一些老年人说:人老眼花,要配副散光眼镜“。其实散光与老花是两回事。老花眼用的镜片和远视镜一样都是凸透镜,所以很多人又把老花眼和远视眼混为一谈,而两者性质也是完全不同的。故散光、老花、远视眼镜三者作用不一样。散光是黑眼珠(角膜)不圆滑,或者晶状体曲度不一致,使垂直入眼的光线和水平入眼的光线经过眼睛复合透镜屈折后,不能同时汇聚在眼底(视网膜)上,而是一前一后分开,这种眼睛称之为散光眼。因角膜弯曲度发生变化所致的散光,多为先天性,度数比较大;若由晶状体弯曲度变化引起,则散光度数比较小。
Often hear some older people said: people are old-eyed, with astigmatism glasses. ”In fact, astigmatism and presbyopia are two different things. Presbyopia lenses and lenses are the same as the convex lens, so many people again presbyopia and hyperopia mixed , And the nature of the two are completely different. Therefore, astigmatism, presbyopia, hyperopia are not the same as the role of the three. Astigmatism is black eyeballs (cornea) is not smooth, or curvature of the lens inconsistent so that the vertical eye into the eye and the level of light After the eye compound lens inflection, can not converge in the fundus (retina), but separated one after the other, this kind of eye is called astigmatism eye .Because the corneal curvature changes due to astigmatism, mostly congenital, Degree is relatively large; if caused by changes in lens curvature, the degree of astigmatism is relatively small.