Research on high precision image measurement system
Penglei Niu, Fengzhi Fu, Hua Tao Fan · 2019
With the rapid development of computer technology, image measurement technology has been widely used because of its non-contact, high precision and other advantages. In recent years, potable consumer devices like mobile phone, VR/AR device, tablet computer etc. become more and more popular. The number of high precision small workpieces has increased exponentially. There is an urgent need for the high accuracy and high speed measurement approach for the quality control of the small workpieces. Due to the contradiction between accuracy and field of view, the existing image measuring instruments are not sufficient, and it is difficult to meet the needs of high precision and high efficiency measurement. In this paper, several aspects of high-precision image measurement system are explored, including hardware system construction, double side telecentric lens design, high-precision template matching technology, system calibration, sub-pixel feature extraction and image segmentation algorithm. According to the actual demand, a high precision detection system is integrated, a high-precision image rapid measurement system for small workpieces (size < 70mm) is designed and developed. The accuracy of 2um and speed of 7000UPH are obtained which can meet the industrial requirements.