六角棱镜调制电脑验光仪对散光眼模型检测精度分析  

Accuracy analysis of auto-refractor using a hexagonal prism in testing astigmatism

作　　者：郭东煜[1] 

机构地区：[1]浙江大学医学院,浙江杭州310058

出　　处：《光学仪器》2014年第6期471-475,共5页Optical Instruments

摘　　要：针对传统电脑验光仪调焦速度慢,聚焦误差大的缺陷,对现有验光仪六角棱镜的成像系统进行优化。通过光学仿真软件分析和对比,发现六角棱镜调制的验光仪在散光度和散光轴位的测量误差(柱镜示值平均误差为0.8m-1,轴位示值平均误差为3.73°)均明显大于普通圆环调制的验光仪(0.2m-1,1.75°)。因此,采用圆环代替六角棱镜调制可以增加检测的精度。另外,对六棱镜分光法设计的验光仪的设计和检验,需要特别注意其柱镜度和柱镜轴位的检测评价,避免造成验光误差。Traditional auto-refractors assure of obtaining focus-image on the CCD by moving focusing lens. Owing to its low efficiency and inspection error, hexagonal prism is used to optimize the imaging system in the many auto-refractors. However, by comparing and analyzing the testing results of model eyes＇ astigmatism and astigmatic axis between a refractor with and without a hexagonal prism, we found that the errors of the refractor with a hexagonal prism （mean error of astimatism 0.8m^-1, mean error of astigmatic axis 3.73°） are much higher than that of the refractor without a hexagonal prism （0.2m^-1, 1.75°）. Therefore, using a fixed small aperture instead of a hexagonal prism may reduce errors on testing astigmatism. Moreover, it would be better to pay more attention to evaluate the performance on testing astigmatism and astigmatic axis in the refractors with hexagonal prisms.

关 键 词：电脑验光仪 六角棱镜 精度分析 散光检测 

分 类 号：TH773[机械工程—仪器科学与技术]