石英消偏器紫外真空紫外消偏特性研究

The Depolarization Characteristic of Quartz Depolarizer in UV-VUV Spectral Region

在Lyot消偏器的基础上 ,设计研制了由两块楔角相同的楔形石英晶体构成的石英消偏器 ,用于降低光谱仪偏振响应度。根据矩阵光学理论 ,数值模拟计算了紫外 真空紫外波段石英消偏器消偏特性随其中心厚度以及入射光偏振状态、光谱带宽等的变化规律。利用氟化锂偏振器作为起偏器和检偏器 ,在 1mSeya Namioka单色仪上实验研究了石英消偏器在紫外 真空紫外波段的消偏特性 ,经过石英消偏器后 ,出射光的偏振度小于 1% ,可满足石英消偏器用于光谱辐射测量的工作要求。

The quartz depolarizer consisting of two wedge-shaped quartz crystals was designed based on the Lyot depolarizer. The quartz depolarizer is used to reduce the polarization response of spectral instruments. The residual degree of polarization of the quartz depolarizer was derived by the method Of matrix optics, so the variation regularity of its depolarization characteristic was analysed concerning its center thickness and the status of the incident radiation in the UV-VUV spectral range. Its depolarization effect was obvious for the radiation with some spectral bandwidth. Also, the depolarization characteristic of the quartz depolarizer was studied experimentally with 1-meter. Seya-Namioka UV-VUV spectrometer, using LiF crystals as the polarizer and analyzer. The residual degree of polarization of the quartz depolarizer was less than 1%. Both the theoretical analysis and experimental results show that the quartz depolarizer we designed is appropriate to the spectral measurement with high accuracy.