In order to control the polarization states and increase the extinction ratio of the TE and TM output beam, a novel tunable polarization controller was proposed and demonstrated by introducing birefringent material into the coupling prism and polymer acted as the guiding layer of symmetrical metal cladding waveguide ( SMCW). In this structure, the guide mode resonance can not simultaneously be excited by TE and TM polarizations at the same incident angle. The incident laser beam energy of the polarization which excites guide mode resonance is coupled into the SMCW, while that of the polarization which dose not excite guide mode resonance is almost reflected. As a result, the TE and TM polarization beams can be separated. Moreover, the polarization selector can be tuned assisted by changing the resonance condition of the guiding mode via applying direct-current voltage on the guiding-layer. The research indicates the inset loss is smaller than 0. 2dB and the driving voltage is up to 19V and the extinction ratio is larger than 27dB due to the twice attenuation totally reflected technique. This method is valuable in many potential applications, such as optical information processing, optical routing, optical switch and image processing.%为了实现激光偏振态的控制和提高两偏振态消光比,用由各向异性材料加工而成的耦合棱镜并采用两次衰减全反射方法,使具有相同入射角的TE和TM偏振态的共振激发条件不同,即当TE偏振态满足共振激发条件能量耦合进波导时,TM偏振态却不满足共振激发条件而被反射来实现其在空间上的分离.同时将电光系数较大、光学性能和热稳定性好的聚合物材料作为波导层,利用其电光效应来改变共振条件来实现输出光束偏振态的调谐.结果表明,反射型结构插入损耗小于0.2dB,器件的消光比高达27dB,驱动电压为19V.该方案预计在光信息存储、光路由、光开光以及图像处理等光学系统里有着极其广泛的应用.
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