软性亲水性接触镜几何参量的光电成像测量方法

Geometrical Parameters Measurement of Contact Lens With A Novel Imaging Method

提出了对软性亲水性接触镜采用非接触的光电成像检测方法·将浸于液体中的软性亲水性接触镜置于高准确度的标准环上,采用投影光学系统将其投影放大,并用光电图像探测器接收软性亲水性接触镜的放大图像.通过计算机图像处理、计算出放大后的图像尺寸,然后利用成像公式、标准环的尺寸等相关参量,最终计算出软性亲水性接触镜的实际几何参量·采用放大倍率为20倍的投影成像光学系统,像元中心距为50μm、像元数为512位的CCD线阵,51系列单片机进行数据处理·经计算,该光电成像测量系统对软性亲水性接触镜的中心厚度、曲率半径的测量分辨力达到了0.005mm,远高于系统0.01mm的准确度要求·

An imaging method to measure the geometrical parameters of contact lens is put forward. In imaging method, contact lens is projected into an enlarged image with a projecting lens. An imaging sensor is used to acquire the enlarged image, and a single board computer is adopted to process the image and to do the calculation of parameters. In addition, a glass ring emerged in the liquid was introduced to hold contact lens without any distortion or dehydration. An example of system is provided. With the system, the thickness t can be measured directly, and fore radius r1 and retral radius r2 can be calculated with the help of h1 and h2 and d1 and d2. With an imaging system of 20 times magnification, and a 512 pixels CCD linear imaging sensor of a 50μm pixel spacing,the system has a resolution of 5 μm, which is much higher than the accuracy requirement of measurement 0.01millimeter.