【摘要】 目的探讨手持放大镜在不同使用条件下对放大倍率的影响。方法探讨以下三种不同情况:①不同阅读材料离放大镜之间的距离。②不同的放大镜离眼睛之间的距离。③不同的阅读近附加对手持放大镜放大率的影响。结果①阅读物从紧贴放大镜的位置开始,越接近放大镜一倍焦距的位置,其放大率越大。②随着眼睛到放大镜之间距离的增大,放大率逐渐减小。③随着调节或者阅读近附加的增大,放大率也增大,并且两者之间存在着线性关系。结论临床低视力工作者应熟悉手持放大镜的光学特性,从而为低视力患者提供更合适的手持放大镜,提高临床低视力康复的成功率。更多还原

【Abstract】 Objective To review the different ways a hand-held magnifier is used and its effect on magnification.Methods Three different conditions are discussed:① magnifier distance for different reading material.② differences in magnifier-to-eye distances.③ differences in accommodation/reading adds,and their effect on the magnification properties of the hand-held magnifier.Results ① Magnification increased within one focal length with an increase in distance from reading material to magnifier.② Magnification decreased with an increase in distance from eye to magnifier.③Magnification increased with an increase in accommodation/reading add,and the relationship between them was linear.Conclusion Optometrists should be familiar with the special properties of the hand-held magnifier so that they can offer more suitable magnification to low vision patients and improve the success of low vision rehabilitation.更多还原