1/4对称膜系偏振分光镜的研制

【作者】 王庆；

【导师】 吴福全；

【作者基本信息】 曲阜师范大学 ， 光学， 2010， 硕士

【摘要】 偏振分光镜是重要的光学器件,广泛应用于光学仪器、激光、光电显示设备和光存储等领域。传统的偏振分光镜由天然光学双折射晶体冰洲石制成,如萨那芒特棱镜、洛匈棱镜、沃拉斯顿棱镜、分束格兰-汤普森棱镜和萨伐尔偏光镜等,这种晶体偏振分光镜具有很好的消光比特性、较大的视场角和宽的分光光谱带宽。冰洲石晶体稀少且大尺寸的难于获得,人工生长的晶体目前只能到几个毫米,达不到制作偏光器件的要求,这些原因造成天然晶体偏光镜价格较高,且不易制造大口径的棱镜,限制了晶体偏光镜的使用。其它实现偏光分束的方法还有利用光学薄膜的干涉、或者制造具有双折射性质的光学薄膜、金属线栅衍射、光子晶体的负折射和布拉格光栅波导等方法。最常用的薄膜偏振分光镜是MacNeille型,国内外都对此进行过广泛的研究。但是MacNeille型薄膜偏振分光镜的视场角较小给使用带来了许多不便,特别是在平板显示和投影设备中,要求有较大的视场角,MacNeille型薄膜偏振分光镜就不能满足使用要求。Li和J. A.Dobrowolski报道了一种基于受抑全反射原理的薄膜偏振分光镜,具有很宽的分光带宽和较大的视场角,但膜层是非1／4规整膜系,并且厚度很薄,很难精确控制,制造非常困难。本文从对称膜系的等效膜层理论和截止带理论出发,研究了倾斜入射时对称膜系s、p偏振分量截止带的分裂特点；利用这种分裂特性,设计了1／4规整膜系的薄膜偏振分光镜；探索了偏振分光镜的镀制参数和封装工艺；利用岛津UV3101-PC分光光度计和搭建的消光比测试系统,对两种膜系结构偏振分光镜的特征参量进行了测试,验证了利用倾斜入射时对称膜系s、p偏振分量等效折射率截止带的分裂设计偏振分光镜是完全可行的,为设计制作高性能、制成工艺简单的薄膜偏振分光镜提供了新途径。全文主要包括以下几个部分。第一章序论部分。对薄膜偏振分光镜的发展历史以及研究现状进行了概述,并对本论文的主要内容进行了说明。第二章倾斜入射时的等效膜层理论。介绍了薄膜光学的基本原理和对称膜系的等效膜层理论和截止带理论。从等效膜层理论出发,利用偏振光学原理,研究了倾斜入射时对称膜系s、p偏振分量截止带的分裂特点。第三章1／4对称膜系偏振分光镜的理论分析。利用倾斜入射时对称膜系s、p偏振分量截止带的分裂特性设计了1／4规整膜系的偏振分光镜和大视场角的偏振分光镜,利用TFCalc薄膜软件对偏振分光镜的分光光谱特性进行了模拟。第四章1／4对称膜系偏振分光镜的制备。主要介绍了薄膜偏振分光镜的镀制过程和封装工艺。为了使镀制的分光膜达到理论预期的效果,对成膜工艺进行了探索；在韩国产EB900真空镀膜机上镀制了偏振分光膜；通过对比试验确定了偏振分光镜的封装工艺。第五章偏振分光镜的性能测试与分析。利用分光光度计和搭建的消光比测试系统,对偏振分光镜的透过率、消光比和视场角特性进行了测试,并对误差做了理论分析,测试结果与理论设计吻合,这种薄膜偏振分光镜性能指标优良。更多还原

【Abstract】 Polarization Beam Splitter(PBS) is an important optical devices, widely used in optical instruments, laser, photoelectric display devices and optical storage fields, etc. Traditional PBS made from natural birefringent crystals calcite, such as Semarmont prism, Rochon prism, Wollaston prism, splitting Glan-Thompson prism and Savart polarizer, etc. This crystal PBS have a good extinction ratios characteristics, the larger field of view angle(FOV) and a broad spectral bandwidth. Calcite crystals are very scarce and the size of small, artificial growth of crystals only can grow to several millimeters, can not satisfy the requirements of produce polarizer, which causes higher prices of natural crystal polarizer can not manufacture large-diameter prism, limiting the use of crystal polarizer. Other methods to manufacture PBS include use of optical thin film interference, or manufacture a birefringent optical film, utilize the metal wire grid diffraction, photonic crystal of negative refraction and Bragg grating waveguide. The most commonly used thin film PBS is a MacNeille type, this type have conducted extensive research at home and abroad.However, MacNeille type thin film PBS in the smaller FOV has brought a lot of inconvenience, especially in the flat panel display and projection devices, require a larger FOV, MacNeille type thin film PBS can not meet the requirements. Li and J.A.Dobrowolski reports a new type thin film PBS based on the principle of frustrated total reflection, with a very wide spectral bandwidth and a larger FOV, but the film layers is not one quarter structured, and the thickness is very thin, so difficult to accurately control, manufacture is difficult.In this paper, use the symmetric film system equivalent film theory and the cut-off theory, study the s, p polarization cut-off characteristics of symmetric film system when the tilt incidence; take advantage of the split features, designed the one quarter structured thin film PBS; Explored the deposition parameters and package techology of the PBS; Using Shimadzu UV3101-PC spectrophotometer and built extinction ratio test system, tested the two kinds of thin film polarization spectroscopic characteristics, proove it is entirely feasible to utilize tilt incidence symmetric film system s, p polarization equivalent refractive cut-off split to design thin film PBS, provides a new way for design and produce high performance, simple process thin film PBS.The full text mainly includes five chapters given as follows.In the first chapter, we introduce the development history of of thin film PBS and give an overview of current study, and the main contents of this paper.In the second chapter, introduced the basic principles of optical thin film and the symmetry equivalent film theory and the cut-off band theory. From the equivalent film theory and polarized light theory, studied the the s, p polarization’s equivalent refractive index cut-off band split characteristic of symmetric film system when tilt incidence.In the third chapter, utilize the symmetric film system s, p polarization equivalent refractive index cut-off band split characteristics when title incidence split designed the one quarter structured thin film PBS and large FOV PBS, used thin film software TFCalc simulated polarization spectroscopic properties of the PBS.In the fouth chapter, mainly introduced the PBS’s film processe and package processes. In order to achieve the theory desired effect, we explored the film deposition process parameters; We manufactured the PBS thin film by Korean EB900 vacuum coating machine; by compared testing determined the assembly process of the PBS.In the five chapter, use of spectrophotometers and built extinction ratios test system, the PBS’s transmittance, extinction ratios and FOV characteristics were tested, and made a theoretical error analysis of the test, the experiment results consistent with the theoretical design, this film PBS have a excellent performance.更多还原