显微动态散斑法测量压电陶瓷位移特征曲线  

Measurement of piezoelectric displacement characteristic curves using dynamic speckle correlation

作　　者：朱猛[1] 黄战华[1] 王小军[1] 蔡怀宇[1] 

机构地区：[1]天津大学精密仪器与光电子工程学院光电信息技术科学教育部重点实验室(天津大学),天津300072

出　　处：《光学精密工程》2011年第4期844-849,共6页Optics and Precision Engineering

基　　金：国家科技支撑计划资助项目(No.2007BA000013)

摘　　要：采用显微动态散斑相关法来测量压电陶瓷的压电位移特性并标定其线性区间。推导了透射相位衍射体在显微系统中的散斑光强互相关函数,并讨论了显微系统分辨率与放大倍率对测量微位移的影响。为在计算中避免散斑去相关的影响,采用了逐级位移相关叠加法。设计了显微散斑采集系统并测量了压电陶瓷的位移磁滞曲线。实验结果表明:使用放大倍率为100、数值孔径为1.25的显微物镜,在测量光路放大倍率为42.1时,测量位移的理论精度达到0.082;考虑衍射极限时,实际的极限位移分辨率为0.348μm。本测量系统满足压电陶瓷位移曲线测量及线性区间标定的要求;与其他方法相比较,该方法简化了测量光路,提高了运算速度,且对装配误差要求低。Dynamic speckle correlation method was presented to measure the piezoelectric ceramic characteristic curves and scale linear intervals in this paper.Firstly,the speckle intensity cross-correlation of a projection phase diffuser in the micro-system was calculated,and influences of the resolution and magnification of the micro-system on object displacement measuring were also discussed.During the calculation of cross-correlation,a progressive correlation method was used to avoid the de-correlation caused by the object surface.A sampling system for micro speckles was designed and the hysteresis curve of displacement induced by a piezoelectric ceramic was measured.Experimental results indicate that the theory precision of the measuring system is 0.082 μm when a micro objective is with magnification of 100 and NA of 1.25.In consideration of the diffraction limit,the theory precision of the measuring system is 0.348 μm.It concludes that the method satisfies the requirements of measuring and scaling of linear intervals.Comparing with other methods,the dynamic speckle correlation can improve the calculation speed and measuring precision.

关 键 词：动态散斑 散斑相关 压电陶瓷 曲线拟合 磁滞曲线 

分 类 号：O436.1[机械工程—光学工程] TN384[理学—光学]