The Study Of Micro-positioning Stage Displacement Detection System Based On Micro Machine Vision

With the rapid development of micro and nano technology, micro-positioning stage displacement detection technology has important applications in microelectronics, MEMS, micro-machining, micro-manufacturing, micro assembly, etc. While, the displacement of the micro-positioning stage is generally in micro and nano level. Micro-positioning stage displacement detection model established on the micro machine vision has been researched and discussed.This topic is a part of the project "study on multi-scale analysis method of generalized particle dynamics in micro nano cutting process", which is supported by the National Natural Science Foundation of China. This thesis focuses on the micro-positioning stage displacement detection and studies the image processing technology of microscopic machine vision measurement system and hardware and software design of microscopy machine vision measuring system based on micro machine vision.First of all, research on the basic principle of microscopic machine vision inspection, and the microscopic image processing algorithm for image enhancement edge detection and rectangular fitting etc were studied.Then, according to the purpose of micro-positioning stage displacement detection, selected the necessary hardware equipment required in the measuring system and established micro machine vision precision detection system, which is compose by computer, high-resolution CCD camera, universal stereo microscope and light source and so on. And select the appropriate image acquisition and processing software such as Toupview, Matlab and Halcon to detect the micro-positioning stage displacement based on the microscopic structures of the machine vision inspection system and specific inspection requirements.At last, the displacement of micro-positioning stage cannot easily be observed in microscopic machine vision inspection system, so the reference pointer is placed on the micro-positioning stage to indicate the displacement of it. To obtain the microscopic image data of movement for the pointer, we used Toupview to record video on the moving pointer which is placed on micro-positioning stage, and picked up the effectively images from the video. To get the pixel location of the pointer corner in the two adjacent image, we intercepted the two adjacent images and processed the image with Matlab and Halcon such as grayscale processing of color images, image enhancement, image segmentation and edge detection. By comparing the variation of the pointer corner pixels in the two adjacent images and re-scaling the ratio between the actual displacement amount and the unit pixel to get the scale factor of the amount of change between the actual amount displacement and the unit pixel, thus can calculate the displacement of the pointer that is displacement of the micro-positioning stage. According to the experimental test results of micro-positioning stage displacement, analyzed accuracy and error of the microscopic machine vision inspection system, achieved the measurement accuracy of the detection system. The results showed that the detection device can be used in the detection of micro-positioning stage displacement.