离轴抛物面镜在温度传感器校准系统中的应用

摘要

In order to improve focusing effect of the crystalline lens on the laser beam in a temperature sensor dynamic calibration system, a 90° off-axis parabolic mirror was used instead of the crystalline lens. The influence of the misalignment angle of the 90° off-axis parabolic mirror on the focused laser spot was studied according to geometrical optics. Utilizing the improved system, the CHAL-010-type thermocouple's time constant at step temperature around 242℃ was tested and the dynamic calibration experiment was carried out. The results show that the new system reconstructed with the 90℃ off-axis parabolic mirror can fulfill the dynamic calibration of temperature sensors.%为了改善温度传感器动态校准系统中的晶体透镜对激光束的聚焦效果,使用离轴90°抛物面镜代替晶体透镜对系统进行了改造,通过几何光学方法,对离轴90°抛物面镜应用于激光聚焦光路时的光轴的角度失准对聚焦光斑造成的影响进行了分析,并利用改进后的系统对CHAL-010型热电偶进行时间常数测试和动态校准实验,得到了CHAL-010型热电偶在温度阶跃为242℃左右时的时间常数值,完成了该热电偶的动态校准.结果表明,采用离轴90°抛物面镜代替温度传感器动态校准系统中的晶体透镜能达到温度传感器动态校准的目的.