铌酸锂光学电场传感器温度稳定性改善研究

铌酸锂晶体材料具有较高的电光系数和稳定的物理、化学性质，广泛应用在各种电场传感器中。但是，铌酸锂晶体折射率对温度较为敏感，在使用最大电光效应方向时，由于自然双折射的存在，晶体工作点随温度漂移，一方面导致传感器无法稳定工作，另一方面也影响了传感器的灵敏度和动态范围。为了消除这一影响，探头中将使用长度相等、主轴正交的两块铌酸锂晶体，一块作为传感晶体，一块作为补偿晶体。由于补偿晶体的存在，传感器的自然双折射得到很大程度的抑制，温度稳定性也得到了改善。经实验对比，补偿之后的传感器工作状态稳定性比未补偿的传感器得到大幅提升。

Improvement of temperature stability of E-field sensor with LiNbO3 crystal

LiNbO₃ crystal has been widely used in various electric field sensors due to its high electro-optic coefficient and stable physical and chemical properties. However, the refractive index of LiNbO₃ crystal is sensitive to temperature. When using the direction of maximum electro-optic effect, the natural birefringence causes the crystal working point to drift with temperature. On the one hand, this makes the sensor work unstably, on the other hand, it also affects the sensitivity and dynamic range of the sensor. To eliminate this effect, two LiNbO₃ crystals with equal optical path and orthogonal principal axes will be used in the probe. One is sensing crystal and the other is compensation crystal. Due to the compensation crystal, the natural birefringence of the sensor is greatly suppressed, and the temperature stability is also improved. The experimental results show that the working state stability of the compensated sensor is much better than that of the uncompensated sensor.