【作者】 徐芝伟；

【导师】 程传福；

【作者基本信息】 山东师范大学 ， 光学， 2011， 硕士

【摘要】 随机表面是自然界最重要的组成部分,小到分子原子构成的物理体系大到山川丘陵都是粗糙的随机表面,对随机表面的研究在许多科学技术领域如:薄膜生长动力学、天体冲击引起的断裂、微电子元件设计等方面有重要的意义,因此随机表面的特性一直是备受关注的研究课题。当适度相干光从粗糙表面反射或通过折射率无规则涨落的媒介传播时,就会形成无规则的强度分布,我们称之为散斑。随机表面产生的散斑特性研究在研究光源的量子纠缠特性等方面也有重要的意义,因此近几年以来,光经过随机表面产生的散斑特性也一直是备受关注的研究课题。自上世纪80年代以来,在对非线性晶体的自发参量下转换过程产生的双光子纠缠态进行的理论和实验研究中,发现了一些新的光学现象,如“鬼”成像、“鬼”干涉和亚波长干涉等.最近一系列新的研究结果表明,“鬼”成像、“鬼”干涉和亚波长干涉也可以用非相干的热光源通过强度关联来实现.这种相似性引发了关于量子纠缠和经典关联的争论。本文的内容主要针对部分相干光的干涉特性的研究,对此进行了大量的理论和实验探讨,取得了重要进展,还研究了影响散斑的各个因素。对散射屏表面粗糙度对散斑图样的影响进行理论分析,给出了散射屏移动对散斑图像的影响,但是这些研究只是初步的,并未深入的作理论分析。本文的具体内容共由五章组成:第一章提出了本文研究内容的意义,部分相干光干涉的背景和最近的发展情况,并对随机表面的描述与测量标定方法和部分相干光干涉在其他方面的应用作了简单介绍。第二章对光学散斑的一阶统计性质进行了系统的介绍,理论上介绍了非相干光和部分相干光散斑图样强度叠加的研究方法,对于非相干光的散斑图样叠加,先从简单的两个散斑图样叠加进行分析,进而应用到N个散斑图样叠加的情况。第三章主要介绍了我们的实验设计,我们在实验中对散斑图样的数值进行叠加,用强度测量的方法观察到了散斑光即部分相干光的类似双缝干涉的现像,并用前面给出的强度叠加理论进行了分析,得到的结果和实验中拍摄的图片想吻合。在我们的实际应用实际测量的过程中,强度值的测量要比强度关联测量简单,而且更容易操作。第四章主要内容是:对实验中得到的图样进一步进行理论分析,利用统计方法求出相应的对比度,分析了各种因素对散斑图样的影响,根据实验得到的图像分析了散射屏的横向移动对散斑干涉图样的影响。这一部分中我们只是对得到的图样中的颗粒和散斑颗粒经过双缝发生的干涉得到的实验结果进行了简单描述和分析,并没有进行更深层次的分析,这将是我们以后工作的重点。第五章对所做的课题研究进行了总结,并提出以后的研究工作的目标和方向。更多还原

【Abstract】 The random surfaces as important parts make up of nature,from atoms and molecules to large mountains and hills are rough random surfaces. It is very important to study it, as it is essential for many aspects, such as the dynamics of film’s growth、rupture aroused by concussion of orb、the design of micro-electronics component and so on. So many people have paid much attention to studying about random surfaces for a long time. When appropriate coherent light reflected from the rough surface or through the medium of Random fluctuations of refractive index, they will form a random intensity distribution, we call it speckle. Studying the characteristics of the speckle through the random surface light source, it is also of great significance in research on the Quantum entanglement properties. So in recent years, the surface has also been a research topic of concern when the light passes through the properties of random speckle.Since the last century 80’s, we found some new optical phenomena during the process of spontaneous parametric conversion producing the two-photon entangled state in the theoretical and experimental studies of the nonlinear crystal, such as the "ghost" imaging, "ghost" interference and sub-wavelength interference and so on. Recently a series of new results show that the "ghost" imaging, "ghost" interference and sub-wavelength interference can also be achieved by using the intensity correlation of the non-coherent heat light. This similarity triggered a Quantum entanglement and classical correlation debate.The content of this paper is the study of the interference characteristics for the partially coherent light. We conducted a large number of theoretical and experimental studies, and has made important progress. We also studied the various factors that affect the speckle pattern. The paper gives the scattering surface’s impact to speckle pattern in theoretical analysis, and the scattering surface movement on the impact of speckle pattern, but these studies are preliminary, not a in-depth analysis. The content of this paper is composed of the following five chapters:Chapter 1 presents the significance of the contents of this paper, give the background and the recent developments of interference with partially coherent light, give a summary of random surfaces and its measurements, and introduce the application of the interference with partially coherent light in other areas.Chapter 2, gives a systematic introduction of optical speckle first-order statistical properties, and gives a research method of incoherent light and partially coherent speckle pattern intensity superposition in the theory. For the sum of incoherent light speckle pattern, firstly we analyses the summing of e two speckle patterns, and then apply to the case of sum of N speckle patterns. Chapter 3, describes our experimental design, sum the value of the speckle pattern in the experiment, and observes the phenomenon of the partially coherent light which is similar to the interference pattern of the double-slit the speckle with the intensity measurement method, and analyses theoretically the results with the sum theory of the intensity given earlier, which are consistent with the experimental results image. In our practical measurement process, the intensity measurement is simpler than the measurement of intensity correlation, and much easier to be operated.Chapter 4, makes further theoretical analysis for the obtained pattern in the experiment, calculate the contrast ration of the speckle pattern in statistical methods, and study the various factors that affect the speckle pattern. We analyses the impact of the transverse movement of the scattering surface for the speckle pattern from the obtained pattern. In this section, we only describe and analyze simply the results which are the interference of the particles and speckle particles through the double-slit, and there is no deeper analysis in this paper, this will be the focus of our future work.Chapter 5, we give the summary of this paper and put forward the further goal.更多还原