Research On High Precision Purification Testing Methods

The purification of a body surface is very important to the performance and precision of an instrument. While the present testing methods of body surface purification are mostly dominated by naked-eye observing, weighing testing, and solvent testing method, etc. Consequently the testing is too much deliberately interfered, and the operation is rather complicated, with a low precision. In order to obtain a quick and all-around testing of the body surface purification in a more accurate and convenient way, this thesis here puts forward the image processing method. This thesis provides a blue print on how to carry out the testing by means of image processing technique, and expounds the image processing method through mathematical morphology. The theory analyses and experiments proved that this method has the strong points of conforming to the definition as well as high precision.Chapter One gives a brief account of the background of surface treatment, provides some criteria of body surface purification testing, and makes a comparison and contrast between some purification testing methods adopted home and abroad, analyzes the advantages and disadvantages of image-processing method, and advocates the necessity to adopt image-processing method to conduct the body surface treatment. In addition, it expounds the significance of the purification testing and brings forward the research orientation and task of this thesis. Chapter Two gives a brief introduction of the mechanical structures and testing principles of the three experimental instruments: flat plate vitreous body, lenticular body and metallic body. It particularly focuses upon the testing principle of mechanical system of the flat plate vitreous body and its mechanical structure design. It also carries out an analysis and comparison of selecting the pick-up head CCD in collecting images. Finally it conducts a comprehensive analysis of the selection and shake down test of the hardware, and the design of collecting video frequency program. Chapter Three introduces some basic knowledge of image and image sampling principles, analyzes the causation of the image noise and some basic relative theories of image-processing methods, meanwhile it presents some basic mathematical rules in mathematical morphology, such as expansion and erosion. Besides, it explains thecommon structural elements in mathematical morphology, expounds the importance of threshold division, which is widely used in image-processing method and compares and analyzes different methods of threshold division. Meanwhile, this chapter introduces some functions of the exploring tools adopted here, Matlab and Visual C++, and DIB of the key BMP file in image processing. And recommends the Visual C++ and Matlab combination digital-image-processing instrument. ChapterFour gives the explanation of instruction value θ(θ= 0.5μm /pel), furthermore itstresses the specific techniques of image processing, gives a specific analysis of pre-image processing, binary, grains per standard cubic foot, function of grain distribution, and the max geometrical diameter and square of grain respectively, and analyzes the method of describing the nature of the image by means of self-correlative function. Finally this chapter analyzes the way to realizing the image-processing software, points out the advantages and disadvantages of the Visual C++ and Matlab combination method. Chapter Five makes a generalization of the whole thesis, and poses some further requirements on the study of body surface purification in future.The precision achieved by this method can reach as high as 0.5μm . in some degreeit realizes the automated data collecting and data processing, meeting the requirements set by this system. In a word, this research sets a foundation for the development of purification testing of body surface.