敲击模式扫描近场光学显微镜

为了实现敲击模式的扫描近场光学显微镜 ,采用以石英音叉为灵敏探测器件 ,将光纤探针垂直音叉侧臂粘接 ,使探针在垂直样品的方向上振动 ,以“敲击”方式探测样品表面的信息 ,实现近场范围的高度控制。仪器结构紧凑 ,操作方便 ,灵敏度高 ,可用于液体环境下的样品探测 ,在对样品形貌进行探测的同时可实现对光信号的调制。将这种探测模式应用于实验 ,获得 2 40 0线 /mm光栅、光盘母盘和生物细胞的形貌图像。实验证明 :这种探测方式分辨率优于 2 0 0 nm,适用于不同硬度的样品 ,可以作为材料学、生物学等领域的有力工具。

Tapping-mode scanning near-field optical microscope

A crystal tuning fork is used as a sensitive detecting element for a tapping mode scanning near field optical microscope (SNOM). An optical fiber probe was attached across one of the tuning fork's tines. The probe vibration perpendicular to the sample surface gave information about the sample topography. The distance between the probe tip and the sample was controlled in the near field distance. The tuning fork/optical fiber probe assembly was compact, easy operated and highly sensitive and the system should be suitable for detecting samples in liquids. The optical signal was modulated to the fiber probe tuning fork frequency as it detects the sample topography. The high resolution of the tapping mode detector was proved by imaging a grating (2400 lines/mm), the mask of a Compact Disk and a biological cell. The results indicate that the tapping mode detector can be widely used to detect topographies. The tapping mode SNOM is a powerful tool for research in materials, biology and other fields.