基于MSP430氦光泵磁敏传感器吸收比测试系统设计

Design of the Absorptance Test System for the Optical Pumping Magnetic Sensor Based on MSP430

针对氦光泵磁敏传感器中氦室制作质量以及相应的共振信号指标是否满足设计要求的问题,介绍了通过测试吸收比来检测氦光泵磁敏传感器中氦室充气量是否达标的新方法,设计了测试实验系统。该系统分3个抽真空阶段,极限真空度可达10 nPa,控制精度约10 Pa,利用MSP430单片机实现测量电压的存储和实时显示,并通过实验的方法来探究氦室吸收比的理想值,以提高光敏元件接收信号的质量。同时给出了系统最终测试结果,实验所测得的吸收比大于38%,通过信号检测和处理电路可以得到较理想的共振曲线,满足氦室的设计要求,对氦光泵磁敏传感器的研制具有实际意义。

In the view of the problem that the existence and quality of the resonance signal are related to the craftsmanship, this paper introduces a new method to test whether the inflating volume in the helium cell of the optical pumping magnetic sensor reaches the standard, and designs an absorptance test system. The system has three phases of vacuumization, the extreme vacuum can reach 10-Spa and the control accuracy is about 10 Pa. MSP430 MCU realizes the storage and display of the data. The ideal value of the absorptance in the helium cell is explored by experiments, and used to improve the quality of the receiving signals by a photosensor. The result shows that the absorptances in the experiment are greater than 38% and the ideal resonance curve can be detected which meets designed requirement through the signal detection circuit, and the design has practical significance for the research of the helium optical pumping magnetic sensors.