T字头石英音叉的设计及其气体传感性能  

Design and Sensing Performance of T-Shaped Quartz Tuning Forks

作　　者：房超 乔顺达 何应 申作春[1] 马欲飞 Fang Chao;Qiao Shunda;He Ying;Shen Zuochun;Ma Yufei(National Key Laboratory of Science and Technology on Tunable Laser,Harbin Institute of Technology,Harbin 150001,Heilongjiang,China)

机构地区：[1]哈尔滨工业大学航天学院可调谐激光技术国家级重点实验室,黑龙江哈尔滨150001

出　　处：《光学学报》2023年第18期134-140,共7页Acta Optica Sinica

基　　金：国家自然科学基金优秀青年科学基金(62022032);国家自然科学基金(62275065,61875047,61505041);安徽大学光电信息获取与控制教育部重点实验室(OEIAM202202);中央高校基本科研业务费专项。

摘　　要：首先,利用有限元分析方法,仿真模拟了石英音叉的应力和表面电荷分布,设计并加工了一种T字头石英音叉。经过实测,此T字头石英音叉的共振频率为8930.93 Hz,Q值为11164,叉指间距为1.73 mm,与目前广泛应用的商用石英音叉相比,T字头石英音叉的共振频率降低了73%,品质因数提高了22%。然后,通过测量水汽对其传感性能进行验证,发现相比于商用石英音叉,基于T字头石英音叉的石英增强光声光谱(QEPAS)系统信噪比提升了60.65%。最后,给出了石英音叉下一步优化的方向。Objective In recent years,harmful gases in the atmosphere have gradually become an important issue of concern for people.Gas sensing technology can perform highly sensitive monitoring of trace gas concentrations,obtaining information on the composition,knowing the concentration changes of gases,and understanding the distribution changes of gases.Quartz-enhanced photoacoustic spectroscopy(QEPAS)technology based on quartz tuning fork detection has the advantages of simple structure,low cost,and strong anti-noise ability,which is a hot spot in the field of gas sensing.In common QEPAS technology,commercial quartz tuning forks are generally used with a resonance frequency of 32.768 kHz,but the performance of QEPAS systems is limited due to high resonance frequency,short energy accumulation time,and small interfinger spacing.Methods In this paper,the finite element analysis method is used to simulate the stress and charge distribution of quartz tuning forks.A T-shaped quartz tuning fork is designed,and the resonance frequency of the T-shaped quartz tuning fork is 8930.93 Hz,with a Q value of 11164 and a cross interfinger spacing of 1.73 mm.In the experimental verification phase,by using water vapor in the atmosphere as the measurement object,the QEPAS water vapor detection system is built.Under the same conditions,we test two types of quartz tuning forks.One is a commercial quartz tuning fork,and the other is a T-shaped quartz tuning fork.A comparison of experimental results between these two quartz tuning forks is performed to verify their detection performance.Results and Discussions The T-shaped quartz tuning fork has a length of 9.4 mm,a width of 1.2 mm,and a thickness of 0.25 mm(Table 1).By using the optical excitation method,firstly,the performance of commercial quartz tuning forks and T-shaped quartz tuning forks is tested separately,so as to obtain the resonance frequency curves of two types of quartz tuning forks.The resonance frequency fo of a commercial quartz tuning fork is 32767.76 Hz,and the quality facto

关 键 词：遥感 石英音叉 石英增强光声光谱 有限元分析 品质因数 信噪比 

分 类 号：O436[机械工程—光学工程]