Blendowske Ralf
*PhD University of Applied Sciences, Optical Technologies and Image Processing, Darmstadt, Germany.
Optom Vis Sci. 2015 Jun;92(6):e121-5. doi: 10.1097/OPX.0000000000000592.
This article proposes a simple model that describes the quantitative relationship between unaided visual acuity and blur attributed to refractive errors.
The standard model for describing the relationship between visual acuity and blur, as published by Raasch, is used as a starting point to develop a simpler model based on heuristic arguments. The basis of Raasch's data is augmented by published findings in the range of low-level refractive errors. Sphero-cylindrical refractive errors are transformed into a single blur quantity b, also termed dioptric distance, which serves as an input in both models. The possible influence of the cylinder axis and the pupil size is not included.
The quite simple model for the unaided minimum angle of resolution, MAR ∝ 1+ b(2), nicely matches available data and improves the SE of the regression by a factor of 2 in comparison to Raasch's model.
Both models considered in this article describe measurement data equally well. They differ in terms of complexity and functional form. The simple model provides a valid description for low-level refractive errors, where Raasch's model fails. Actual uncertainties in experimental data on unaided visual acuity, especially the frequent lack of information on pupil diameter, prevent meaningful numerical comparison and the refinement of both models. However, theoretical arguments are provided in support of the simple model.
本文提出了一个简单模型，该模型描述了裸眼视力与屈光不正所致模糊之间的定量关系。
以拉施（Raasch）发表的描述视力与模糊关系的标准模型为起点，基于启发式论证开发一个更简单的模型。通过低水平屈光不正范围内已发表的研究结果来扩充拉施数据的基础。将球柱面屈光不正转换为单一的模糊量b，也称为屈光度距离，它在两个模型中均作为输入。未考虑柱镜轴和瞳孔大小的可能影响。
关于裸眼最小分辨角（MAR）的相当简单的模型，即MAR ∝ 1 + b(2)，与现有数据匹配良好，并且与拉施模型相比，回归的标准误差（SE）提高了2倍。
本文中考虑的两个模型对测量数据的描述同样良好。它们在复杂性和函数形式方面存在差异。简单模型为拉施模型不适用的低水平屈光不正提供了有效的描述。裸眼视力实验数据中的实际不确定性，尤其是经常缺乏瞳孔直径信息，妨碍了有意义的数值比较以及两个模型的优化。然而，提供了理论论证来支持简单模型。
