利用石英晶体的线性电光和电致旋光强度调制

Linear Electrooptic and Electrogyration Intensity Modulation Using Crystalline Quartz

提出并实验研究了利用石英晶体自身特性产生光学偏置的线性电光调制器。利用某些电光晶体的自然旋光性和自然双折射,并合理设计晶体尺寸及其晶轴与光传播方向之间的夹角,可以提供所需要的光学偏置以实现大动态范围的线性电光调制。对于兼有电光和电致旋光效应的晶体,例如石英晶体,应考虑综合利用这两种效应对电光调制的贡献。实验研究了一块石英晶体的电光强度调制特性,在27V～4.5kV工频调制电压范围内,调制输出信号与调制电压之间的线性相关系数大于0.9999。

A linear electrooptic modulator using crystalline quartz is proposed and experimentally investigated, and its optical bias is produced in the crystal itself. Required optical bias can be produced from the natural birefringence and optical activity of a crystal if the dimensions of the crystal and its dielectric axis azimuth to light propagating direction are properly designed. For crystals exhibiting both electrooptic Pockels effect and electrogyration effect, such as crystalline quartz, it is better to simultaneously make use of the two effects to increase its modulating sensitivity. The experiment on electrooptic intensity modulation using crystalline quartz is performed for the modulating voltage from 27 V to 4.5 kV, and the linear correlation coefficient between output signal and modulating voltage is no less than 0. 9999.