Greivenkamp J E, Schwiegerling J, Miller J M, Mellinger M D
Department of Ophthalmology, University of Arizona, Tucson, USA.
Am J Ophthalmol. 1995 Aug;120(2):227-40. doi: 10.1016/s0002-9394(14)72611-x.
We developed a methodology to predict changes in visual performance that result from changes in the optical properties of the eye.
Exact raytracing of schematic eyes was used to calculate the point spread function and the modulation transfer function of the visual system. The Stiles-Crawford effect, photopic response, diffraction, and the retinal contrast sensitivity are included in the model. Visual acuity was predicted by examining the modulation of the resultant retinal image of a bar target and by determining when the modulation falls below a threshold value. Visual acuity was predicted for refractive errors ranging from 0 to 5 diopters and for pupil diameters ranging from 0.5 to 8 mm.
Visual acuity predictions were compared to clinically found Snellen visual acuities and were found to be highly correlated (r2 = .909).
This modeling technique shows promise as a means of evaluating clinical and surgical procedures before undertaking clinical trails.
我们开发了一种方法来预测因眼睛光学特性变化而导致的视觉性能变化。
使用精确的示意图眼睛光线追踪来计算视觉系统的点扩散函数和调制传递函数。该模型包括斯泰尔斯-克劳福德效应、明视觉响应、衍射和视网膜对比敏感度。通过检查条形目标的合成视网膜图像的调制并确定调制何时低于阈值来预测视力。针对0至5屈光度的屈光不正和0.5至8毫米的瞳孔直径预测视力。
将视力预测结果与临床发现的斯内伦视力进行比较，发现两者高度相关（r2 = 0.909）。
这种建模技术有望成为在进行临床试验之前评估临床和外科手术的一种手段。
