基于力平衡原理的非接触式眼压计研制

Research and fabrication of noncontact tonometer based on principle of force equilibrium

提出一种基于力平衡原理和空气静压技术相结合的非接触式眼压计设计方法。介绍了非接触式眼压计的总体结构、眼压测量模块和外框式气浮垫的设计。其中,眼压测量模块主要包括喷嘴、角膜对准系统及角膜压平光电检测系统,外框式气浮垫采用小孔节流式静压止推气体轴承结构,用于悬浮无摩擦的承载眼压测量模块。对外框式气浮垫的压力分布进行了计算和仿真,对角膜压平光电检测系统和非接触式眼压计的性能进行了测试。实验结果显示:在喷嘴到眼角膜距离为额定距离L的情况下,喷嘴喷出的气体可压平眼角膜,此时光电接收管接收到的光电信号最大,与进口仪器相比眼压测量平均值的绝对误差为1.3 mmHg,研制的非接触式眼压计可实现对眼压的非接触测量。

A noncontact tonometer design method is presented,based on force balance principle and air static pressure technology.Overall structure of a non-contact tonometer design of intraocular pressure measurement module and frame type air cushion are introduced.The intraocular pressure measurement module includes nozzle,corneal alignment system and a corneal applanation photoelectric detecting system.Frame type air cushion adopts the orifice of aerostatic thrust bearing.The pressure distribution of external frame type air cushion,and test the nozzle and corneal photoelectric detecting system are calculated and simulated.The experimental results show that when distance between cornea and nozzle is rated distance L,nozzle gas can be flat corneas,photoelectric receiving pipe just receives maximum light.Compared with imported instruments,absolute error of measuring mean value is 1.3 mmHg,development of noncontact tonometer can realize noncontact measurement.