【作者】 赵瑞冬；

【导师】 孙平；

【作者基本信息】 山东师范大学 ， 光学， 2011， 硕士

【摘要】 电子散斑干涉法在逆向工程、机器视觉、无损检测、产品的在线监测,特别是物体三维形貌的测量上有着广泛的应用前景,是光学测量的重要分支,具有全场性、高精度、非接触的优点。电子散斑形貌测量技术基于传统的散斑干涉技术,而且具有散斑干涉的一系列优点。本文就电子散斑干涉法与相移法和傅里叶变换法结合测量物体三维形貌进行了研究与讨论。介绍了散斑的成因和产生方法,回顾了三维形貌测量的发展过程,从理论和实践两个方面对电子散斑干涉法进行了深入的研究。电子散斑干涉测量形貌的基本原理是光的干涉,取两束光强相等的光束分别作为物光和参考光,使物光和参考光发生相干干涉,从而产生明暗相间的散斑干涉条纹。若待测表面是平面,则干涉条纹是间距相等的直条纹。由于物面高度的起伏变化,会使干涉条纹发生弯曲变形,而物面的相位信息就包含在弯曲变形的干涉条纹里。采集系统采用CCD摄像机,计算机针对获取的变形条纹图进行滤波、去噪以及实时相减等一系列图像处理,提取相位信息,进而重构出物体表面的三维形貌。通过把相移技术和散斑干涉结合起来,本文详细阐述了形貌测量的原理,提出了一种利用电子散斑相移技术测量物体三维形貌的实验方法。该方法以电子散斑为信息载体产生干涉条纹,利用相移技术对待测物面施加相移,实现相位变化。对实验测量中的关键技术,如相位提取、相位解包算法和相移方法进行了深入的探讨。基于理论讨论,本文分别从产生条纹的方法(例如投影栅线和电子散斑干涉)和提取相位的方法(例如相移法和傅里叶变换法)两个方面进行实验研究,以四步相移为例利用计算机模拟了圆柱体的表面形貌;基于电子散斑干涉的原理,分别用相移法和傅里叶变换法两种相位测量方法测量了球冠的表面形貌,得到了较满意的实验结果。更多还原

【Abstract】 Electronic speckle pattern interferometry in reverse engineering, machine vision, NDT products online monitoring, especially in the measurement of 3-D shape of object has a broad prospect of application. Is an important branch of the optical measurement, with the advantages of whole field, high accuracy and non-contact. Based on the traditional speckle pattern interferomery, Electronic speckle pattern interferometry has a series of advantages of speckle pattern interferomery.In this paper, the combing with electronic speckle pattern interferometry and phase-shifting and the combing with electronic speckle pattern interferometry with Fourier transform are studied and discussed. In this paper, the cause of formation and generation methods of speckle pattern have been introduced. From two aspects of theory and practice of electronic speckle interfering method is studied, through Reviewing the development of 3-D shape measurement process. The basic principle of measuring 3-D shape with Electronic speckle pattern interferometry is light interference, that is taking two light beams with equal light intensity as object light and reference light respectively. Making object light and reference light interference in order to produce speckle interference fringes. If the measured surface is flat, the interference fringes are straight. Because of the surface height fluctuation the object has, the interference fringes become bend. And the phase information that is included in the bending deformation in the interference fringes. CCD camera is used in Acquisition system. For deformation of the computer access fringe image processing, such as filtering, de-noising and a series of real-time subtraction, then information and extracting phase are worked out, and 3-D surface shape can be reconstructed.Through combining phase-shifting with speckle pattern interference, this paper explains the principle of the 3-D shape measurement in detail, and put forward a kind of experiment al method that is using electronic speckle phase shift technique to measure object’s 3-D shape. This method takes the electronic speckle pattern for information carrier interfere stripe, and uses the phase-shifting in order to change the measured phase. The key to the experimental measurement technique such as phase extraction, phase unwarping algorithm and phase-shifting method has been thoroughly discussed in the paper. Based on the theoretical discussion, the experiments are taken on two methods such as the methods to produce fringes(e.g. projection line and electronic speckle interference) and extraction phase methods(e.g. phase-shifting and Fourier transform). To four step phase-shifting, for example, a cylinder surface topography can be simulated by using computer. Based on the principle of electronic speckle interference, respectively for phase-shifting and Fourier transform, the methods of measuring the ball surface topography of the crown obtained satisfactory results of the experiment.更多还原