Research on measurement of optical lens radius based on image processing

摘要

In optical test technology, the optical parameters measurement is common. Different optical parameters of the optical system represent the different characteristics. The accuracy and precision of optical parameters measurement are influencing the performance evaluation directly. Sphere radius which is decided the optical properties is a main parameter of lens. But the traditional measuring method has many problems. There are testing cost, contact measurement, the required test pieces, test range, accuracy and so on. Therefore, it is necessary to find out a lower-testing cost, higher precision and non-contact measurement method. According to the shortcomings and deficiencies in radius measurement, a fast, high-efficient, intelligent way has been researched. This paper proposes a measuring method of radius based on the image analysis. Processing with MATLAB is used for dealing with the collected image. Two points are gained by auto-collimation. The radius is the difference between the vertex and centre of sphere. Conduct the experiments separately with plane convex lens and plane concave lens. The experimental results indicate that the measurement method presented in this paper have less than ±0.15% relative error and ±0.25% repeatability.