【作者】 韩玉晶；

【导师】 国承山；

【作者基本信息】 山东师范大学 ， 光学， 2006， 硕士

【摘要】 光学涡旋(Optical Vortices)是一种具有螺旋型波前结构和确定的光子轨道角动量的特殊光场,近年来,受到科学界的重视,并被广泛的研究,目前已经发展成为现代光学的一个新的研究领域;已经在光学微操纵、原子光学、生物医学、非线性光学、光学信息传输等领域得到了重要而广泛的应用。本论文重点对光学涡旋的产生方法、衍射特性及其实际应用中的有关问题进行理论与实验研究。主要研究内容和结果如下:1.总结论述了光学涡旋的数学描述、产生方法及在近轴情况下光学涡旋场的轨道角动量特性。2.分析了阶梯型螺旋相位板产生的涡旋光场的涡旋特性,分别给出了实现最大总轨道角动量输出、最小总轨道角动量、最大主光学涡旋轨道角动量和高纯度的光学涡旋场输出的条件。为螺旋相位板的设计和实际应用提供了参考依据。3.从理论上解释了利用具有相位调制偏差的液晶空间光调制器产生周期性强度调制光学涡旋场的原因,并提出利用这种方法可以检测液晶空间光调制器的相位偏差。4.分析了螺旋相位滤波系统的一些特性,提出利用这种方法产生任意形状以及任意排列的光学涡旋场,为我们研究微观颗粒在阵列光学涡旋场中的受力以及阵列光学涡旋场的传播动力学提供了实验基础。5.在用螺旋相位板进行光学径向希尔伯特变换的基础上,提出了一种利用拉盖尔-高斯空间滤波器来实现光学径向希尔伯特变换的新方法,并从理论与实验上证实了该方法的可行性。理论与实验结果表明利用这种方法能够有效的增强物体的边缘信息,提高对比度。更多还原

【Abstract】 Optical vortices are intriguing special optical structures with helical (or spiral)wave fronts, which attract much attention for their well-defined orbital angularmomentum(OAM) properties. This kind of special optical field has been applied inmany fields that include optical micromanipulation, atomic optics, biomedicine,nonlinear optics, or quantum information processing. In this thesis, we explored thegeneration mehtods of optical vortices, their diffractive properties and applications.The major content and result are as follows:1. We made a description of optical vortices, introduced some method to generateoptical vortices and analyzed the angular momentum of the optical vortices underparaxial condition.2. We analyzed the vortex properties of the field generated by multi-level stepspiral phase plate, and gave the condition for generation of optical vortices withmaximal OAM, minimal OAM and high purity, which provide us some usefulparameters for designing the spiral phase plate and its applications.3. We explained the relationship between modulation depth of optical vortices andthe phase deviation of the spatial light modulator in theory. This theory provide apossible approach to measure the phase deviation of SLM.4. We analyzed the properties of the helical phase spatial filtering system andproposed a new method to generate optical vortices with any shape and array byuse of helical phase spatial filtering. This method offers an advanceduser-interactive functionality and high adaptability, which are important forapplications in study of optical micromanipulation of a mixture ofmicrostructures, optically induced photonic lattices, and lattice of optical vortexsoliton.5. We introduced a new method to implement radial Hilbert transform by use oflaguerre-gaussian spatial filters and demonstrated the feasibility of this method intheory and experiments. The result implied that using this method can enhancethe edge information of the image effectively and advanced the contrast.更多还原