石英玻璃太赫兹光学参数测量的误差分析

测量液体或气体样品的太赫兹光学参数时,常采用石英玻璃作为容器,因此在计算样品的折射率和吸收率时需要考虑石英玻璃太赫兹光学参数的影响。文中利用太赫兹时域谱技术测量了石英玻璃的太赫兹时域光谱,根据测量模型计算了太赫兹波段的折射率和吸收率,并利用误差传播理论分析了这些光学参数的误差。结果发现折射率误差在0.2~2.0 THz范围内基本保持不变,而吸收率误差则随频率增大而呈指数增大。这对于提高测量石英玻璃容器中的气体及液体样品太赫兹光学参数的准确性具有重要价值。

Error analysis of quartz glass terahertz optical parameter measurement

When the THz optical parameters of gas or liquid samples in quartz glass container were measured in the most cases, the influence of THz optical parameters quartz glass should be considered. The time domain spectroscopy of quartz glass was measured, then it's the refractive index and absorption coefficient in THz band were calculated by the analytical formula. At last the error of its optical parameters was analyzed by the theory of error propagation. It is found that the error of the refractive index is almost invariable in 0.2-2.0 THz, and the error of the absorption coefficient is exponentially increasing with frequency increasing. The result is significant for improving the accuracy of THz optical parameters of gas or liquid samples in quartz glass container.