自然验光仪的光路设计及屈光度测量实验

摘要

In order to reduce the impact of eye’s self-control on the diopter measuring, an open-view optical system of natural refractor is established and its optical imaging characteristics and diopter measuring method are investigated. And a method of optometry by measuring the ring thick of the reflection image, rings thick method for short, is proposed. Firstly, the optical path of the open windows type natural refractor and its working principle are introduced. Next, the relationship between diopter and far point distance is obtained through theoretical analysis and the ring thick method is proposed to measure the far point distant. Then, build related eye models to verify the optical system’s simulation performance by Zemax. Finally, set up the related optical system to test nine simulation eyes. The experimental results indicate that the relative error of the nine simulation eyes is controlled within 7%. These results satisfy the requirement of diopter measuring very well and the optical system is characterized by compact structure, low cost, good accuracy, and high stability.%为了降低眼球的自动调节功能对屈光度测量的影响，建立了敞开视窗型自然验光仪光学系统。对该系统的光学成像特性、屈光度测量方法等进行研究，提出了一种通过测量眼底反射像环的厚度来验光的方法（简称环厚法），同时还设计了一组适合环厚法的调焦光路来实现。首先，介绍了敞开视窗型自然验光仪的光路结构及工作原理。接着，通过理论分析得出屈光度与远点距之间的关系，并提出环厚法用于测量远点距。然后，在Zemax软件中建立相应的光学模型进行仿真测试，最后，通过搭建相应的光学系统对九种模拟眼进行实验测量。实验结果表明：九种模拟眼测量的相对误差控制在7%以内。该光学系统具备结构紧凑、成本低、准确、稳定可靠等特点，能够满足屈光度测量的要求。