【作者】 刘超；

【导师】 李晓彤； 岑兆丰；

【作者基本信息】 浙江大学 ， 光学工程， 2012， 硕士

【摘要】 一套好的对于光束能量和偏振态的分析方法将对我们设计光学系统起到很好的指导作用。在光学系统中,不同偏振态光束的能量的计算方法是不同的。由于在振动面内任意方向都存在着振动,无偏振光和部分偏振光传播时能量和偏振态变化情况比较复杂,在某些情况下,例如大数值孔径成像时,光束的偏振态还会影响成像质量。借助光线追迹的方法,本文对不同偏振态光束的能量和偏振态分析方法做了较系统的研究。本文的创新点在于,针对无偏振光和部分偏振光,首先提出了一种用采样线偏振光来描述非完全偏振光能量和偏振态的方法,该方法具有较好的直观性,较高的精度,但是计算量较大。为了减小计算量,本文又提出一种光线椭圆方法,该方法引入光线椭圆来描述非完全偏振光能量和偏振态,并采用光线椭圆叠加的办法来分析光束在光学系统传输时能量和偏振态的变化情况。文章选取不同的光学系统,举例介绍了这两种分析方法的应用,最后并对大数值孔径、高像质的齐明透镜系统讨论了入射无偏振光能量、偏振态的变化,以及大数值孔径带来的偏振效应问题。结果表明,大数值孔径使成像光束中TM偏振光强度相对增加,影响成像对比度；提高像方介质的折射率,例如将像方介质改为折射率油,会改善此种偏振效应问题。更多还原

【Abstract】 An excellent analysis method for light power and polarization will be a good guidance for us to design optical systems. Calculation methods on power of light with different polarization state are different. It is difficult to process changes in power and polarization for non-polarized light and partially polarized light whose vibration directions are arbitrary in vibration planes. The light polarization will also affect the image quality in some cases, for example, when imaging with large numerical aperture. Based on ray tracing principle, for light with different polarization state, analysis methods for changes in power and polarization state are systematically researched in this paper. The main innovations are as follows:firstly, sampled linearly polarized light is used to describe the power and polarization state of incompletely polarized light, this method is intuitive and has a good accuracy, but it needs a large amount of computation. In order to decrease computation, another novel method is proposed. Ray ellipse is introduced to describe power and polarization state of light, and an approach of superimposing ray ellipses is used to analyze their changes. To introduce the applications, many optical systems are discussed with these methods. At last, an aplanatic lens system characterized by large numerical aperture and high image quality is simulated. Changes in power and polarization of incident non-polarized light are discussed and polarization effect caused by large numerical aperture is analyzed with this method. The results show that for the imaging light the intensity of TM polarized light relatively increases because of large numerical aperture, which will influence image quality. Imaging in high refractive index medium can be used to improve this polarization effect problem.更多还原