用于激光驱动飞片诊断的线成像速度干涉仪

设计并建立了一套完整的线成像激光干涉测速系统,用于激光驱动技术中小尺寸飞片或样品一条线上所有点的速度测量。它将激光压缩为线状照射到靶面,用成像物镜收集靶面的漫反射光并传递到广角迈克尔逊干涉腔中形成干涉,产生的梳妆干涉条纹作为信号载体,用变像管扫描相机记录条纹随时间的变化,用不同位置的条纹移动量反推出不同位置的速度分布,实现空间分辨。系统具有50 ps响应时间和20μm空间分辨能力。用该系统测量了激光驱动飞片的速度场,清晰的扫描干涉图像直观显示了飞片的运动过程和各点的速度差异。用傅里叶变换方法对干涉图像进行处理,得到了靶面一条线的速度和位移分布。

Line-imaging velocity interferometer for laser driven flyer diagnostics

A line-imaging velocity interferometer was developed and implemented, which is used for laser-driven-flyer velocity measurement with high temporal and spatial resolution. Based on VISAR and ORVIS, this system reshapes the probe laser to line light on the target, collects scattered reflection by imaging lens, uses a wide angle Michelson interferometer to produce a comb fringe as velocity information carrier and records the image using streak camera. The velocimeter is capable of 50 ps temporal resolution and 20 μm spatial resolution. Velocity measurement for Al flyer driven by laser was implemented to test this system. Very intuitive image records and data processing results provided a large number of valuable information, confirming that the velocimeter is adequate for laser driven flyer