四分压电陶瓷管低频振荡现象的发现和探讨

利用光纤测振干涉仪实现了对近场光学显微镜中四分压电陶瓷管的扫描参数的测量。在测量过程中发现，陶瓷管对驱动阶梯波每个台阶的响应出现了几个周期的准衰减振荡信号，其频率远低于公认的最低谐振频率。压电陶瓷管的这种低频振荡将带动探针一起振动，从而使所得图像的质量降低，并大大限制了图像扫描的速度。研究结果表明，该振动是压电陶瓷管自身所固有的，而在以前的扫描探针技术研究中并没有得到重视。因此减小振荡的影响将是获得高分辨率图像的关键问题之一。

Discovery and Discussion of Low Frequency Vibration of Four segment Piezo tube

Scanning parameters of four segmented piezotube can be characterized by an optical interferometer. During the measurement decay vibration with several period is observed when the tube is driven by square wave. The vibration frequency is much lower than the lowest calculated resonant frequency based on the report formula. This will result in tip vibration together with the tube. Quality of optical image will be degraded and the scanning velocity will be limited greatly. However the research shows that the vibration is determined by piezotube itself. How to reduce the influence of low frequency vibration for reliable image will be one of key problems of SNOM.