日本东京大学生产技术研究所和芬兰约恩苏 ( Joensuu)大学共同研制出可测量 1 0 nm以下振幅的非接触振动测量系统。用光折变效应 ,即使是散射光也完全可以测量 ,并能抗干扰 ,可在生产现场的恶劣环境下使用。光折变效应是在材料上照射具有空间强度分布的光时 ,折射率发生变化的 The Institute of Production Technology, University of Tokyo, Japan, and Joensuu University, Finland have jointly developed a non-contact vibration measurement system that can measure amplitudes below 10 nm. With the photorefractive effect, even scattered light can be fully measured, and can be anti-interference, can be used in the harsh environment of the production site. The photorefractive effect is the change in the index of refraction when the material is irradiated with light having a spatial intensity distribution