| From the 1960's, especially after the born of laser and optical fiber, the development of Polarization Optics speeded up. With the rapid development of Polarization Technology, it is urgent to know the polarization character of the light beam. There is the most popular method among all the methods that describe polarization state of light beam. We named it Stokes method which use four parameters to describe the polarization of light beam. The four parameter use the same physics dimension. Stokes vector can combine with Muller matrix which describe the nature of polarization device. Their combination can solve all the problem of light's transmission. It is the score of matrix optics also. The measurement of Stokes parameter is not only significant in the way of theory, but also is of actual value. The Stokes parameter of light which is emitted or reflected by some objects can show the information of these objects themselves, so the measurement of Stokes parameter is used widely in the way of remote sensing and the recognition of military target.After searching and reading many theses and dissertations, we found the existing measurement systems of the Stokes parameters, generally ,can measure the parameter of one dot on the sample, lacking uniformity, and it usually cost lots of time to collect and analyse the data. Because of these reasons, the old measurements lack of credibility. In general, there are two methods that can detect the energy distribution of transversal surface of the light. They are photosensitivity and scansion. However, the two methods have some shortage such as being short of information, great inaccuracy and being unable to detectand display at real time. After screening and comparison carefully, we choose CCD, a new optical-electrical converter with stable performance, as the score device of the measurement system. We do many experiments. We do much work especially in the way of choosing device, designing the light path, working out procedure codd determine working condition and so on. Finally, we exploit a set two-dimentional intelligent measurement system of light beam's polarization state. This is an optical-mechanical -electrical-computerized system. We programmed a set of software using visual basic in Windows2000 Professional to control the measurement system. The software is intelligent, it can operate the systenu analyse data and result. It can measure the Stokes parameter polarization degree and Jones vector automatically. The experiment results coincide with the theory. The system has achieved its goal. This thesis is stated from the following aspect.In the first Chapter, we mainly introduce the history of Stokes parameter and the significance of measurement Stokes parameter. We also introduce new light intensity detector-CCD briefly. In the second Chapter, we mainly introduced the typical methods which is used to describe the polarization state of light beam and their relation. We can follow that the Stokes method is most popular among these methods. In the third chapter, we stated the programme of the measurement system and designed a set of experiment system which can approve whether the programme is a feasible program.The forth chapter is the score of the thesis. In this section, we introduced single-dot measurement system of Stokes parameter and polarization degree, we performed the experiment and the experimental results are given. We mainly introduced two-dimentional measurement system. Choose linearly polarized lightof 90 degree and right-circularly polarized light as two examples, we working out their experimental results figuratively and visually. In this part, the method of adjustment light-path, steps of test and measurement, system flowchart and windows menu are provided.In the fifth chapter, the experimental devices used in the system are given, and we analysed the sources of the inaccuracy and the methods of reducing the inaccuracy. The inaccuracy came from power shift of laser, position angle error of each component, distinguish ability limit, nonunifor... |
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