低频水下声信号的激光探测  

Detection of low-frequency underwater acoustic signal by laser

作　　者：苗润才[1] 许佳婷[1] 谢甜[1] 王文成[1] 

机构地区：[1]陕西师范大学物理学与信息技术学院,陕西西安710062

出　　处：《应用光学》2012年第5期974-978,共5页Journal of Applied Optics

基　　金：陕西省重大科技创新专项资金项目(2010ZKC01-18);陕西省自然科学基金(2010JM1003)

摘　　要：根据表面波声光效应的原理,提出了一种低频水下声信号的激光探测技术,并建立了实验装置。在几十赫兹的低频段,对水下声源所产生的表面声波进行了探测。实验过程中,利用MATLAB软件对拍摄的衍射图样进行扫描分析,得到了衍射图样中条纹的像素差。根据波长与条纹间距的解析关系式,得到了低频液体表面声波波长,其大小在毫米量级。利用计算机编程,根据最小二乘法拟合色散关系的回归曲线,测量结果与理论色散关系吻合。该方法具有实时、非接触的特点。According to the principle of the surface acoustic wave （SAW） effect, a technology has been developed to detect the low-frequency underwater acoustic signal by laser and a detec-tion apparatus is developed. In dozens of Hertz low-frequencies, the surface wave produced by the underwater acoustic was detected. In the measurement process, the diffraction pattern was scanned by using MATLAB to analyze. Then the diffraction pattern pixel of stripe was ob- tained. According to the analytic formula o{ the wavelength and stripe space, the low-frequen- cy liquid Surface wavelength with millimeter order was obtained. By using computer program-ming, the regression curve was fitting according to the principle of least square method. Meas-urement results agree with the theoretical dispersion relationship. The method has the charac-teristics of real-time and non contact.

关 键 词：声光效应 水下声源 表面声波 色散关系 

分 类 号：TN249[电子电信—物理电子学] O436.1[机械工程—光学工程]