Hyperopia long - sightedness a long - sighted or hyperopic eye is shorter than normal 远视的主要成因是眼球长度比正常短或角膜的弧度不足。
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Corneal surfaces in eyes with regular astigmatism are thought to be toroidal surfaces . based on mathematical models for corneal surfaces before and after treatment , a corneal ablation model is given for such refractive errors as spherical myopia , compound myopic astigmatism , and simple myopic astigmatism . a similar corneal ablation model is also given for such refractive errors as hyperopia , compound hyperopic astigmatism , and simple hyperopic astigmatism 采用超环面( toroidalsurface )建立起规则散光下的角膜曲面模型方程;定量研究了手术光学区屈光不正两种通用的矫正模型,一种模型适用于单纯近视、复性近视散光、单纯近视散光的矫正,另一种模型适用于单纯远视、复性远视散光、单纯远视散光的矫正;另外,作为影响手术效果的重要因素,提出了一种用于光学区直径和过渡区宽度均可调节时过渡区角膜切削量的计算模型。
