ABSTRACT

Temperature monitoring plays an increasingly important role in research and industrial applications. Based on the influence of liquid crystal material thermal sensitivity on the capacitance of liquid crystal cell, the sensing performance of the capacitive-type liquid crystal temperature sensor were studied. By testing the capacitance under the voltage from 0 V to 20 V at different temperatures, the capacitance–voltage curve is drawn, and then the relationship between the capacitance change rate and the temperature at different voltages was obtained, so as to analyse its sensitivity. The results show that the capacitance of the liquid crystal material (RDP-09 T-100) is linearly related to the temperature in the temperature range of 20–110°C, even when the applied voltage is 0.1 V, which proves its feasibility as a temperature measuring medium for the temperature sensor and shows that the sensor has the advantage of low power consumption. When the applied voltage is 15 V, the sensitivity of the capacitive-type liquid crystal temperature sensor can reach 0.94 pF/°C and its response time is 0.115 s/(pF.°C). This research further expands the application scope of liquid crystal and has certain guiding significance for the development of new temperature sensor.

摘要

温度监测在研究和工业应用中发挥着越来越重要的作用。基于液晶材料热灵敏度对液晶盒电容的影响，研究了电容式液晶温度传感器的传感性能。通过测试不同温度下0V~20V电压下的电容，绘制电容-电压曲线，进而得到不同电压下电容变化率与温度的关系，从而分析其灵敏度。结果表明，液晶材料（RDP-09 T-100）的电容在20-110°C的温度范围内与温度呈线性相关，即使施加的电压为0.1 V，证明了其作为温度传感器测温介质的可行性，表明该传感器具有低功耗的优点。当外加电压为15 V时，电容式液晶温度传感器的灵敏度可达0.94 pF/°C，响应时间为0.115 s/(pF.°C)。本研究进一步拓展了液晶的应用范围，对新型温度传感器的开发具有一定的指导意义。