Digital Image Processing Technology In The Plane Such As Dumping Interferometry

In the Equal Inclination Interference (EIIT) measurement, the flatness characteristics of detected optics can be extracted from its fringe in the interferogram, which is white alternating with black. It is important to record and analyze the interference fringes. But the traditional measuring process was very onerous and weary because the instrument has limitation. It resulted in lowly efficiency and lowly accuracy. With the development of modern electronic technology and computer and image processing technique, the method of combining with the technique based on image sensor, computer control, image processing is the best solution of the Equal Inclination Interference measuring system which combining with full-automation, high precision and high efficiency.This paper puts forward a novel method of Equal Inclination Interference measurement by applying image processing technique. Thesystem, based on the theory of EIIT, can be applied to grasp the changingfringe information through the CCD camera. The data processing of the interference fringe consists of image smoothing, frame thinning, fringe center extracting and fringe diameter measurement. Through the full and accurate data processing we present the measurement result. As for the image calibration and measuring system always have measurement errors, this paper also analyzes the reason of errors in the CCD EIIT measurement and presents the method of erasing errors.A great deal of measuring experiments have proved that CCD EIIT measuring system is the guarantee of automatic measuring of interference fringe in real time. Based on image processing technique, automatic real-time CCD EIIT measuring system is useful in metrology department for the high-precision flatness standard unit, which is helpful to control the product cost for enterprise with practical value.