双光束白光干涉系统的理论模拟与实验研究

为了实现一般性样品的自由电子激光三维成像,搭建了一套用于上海软X射线自由电子激光装置的双光束单脉冲三维成像装置。计划利用可见光对该成像装置进行离线时空对准,利用自由电子激光对其进行在线时空对准。为了保证离线对准的顺利实现,需要搭建一套基于双光束白光干涉原理的离线对准系统。本文设计了一套双光束白光干涉系统,并结合波动光学原理和MATLAB软件对其进行了离线对准原理的理论模拟验证。随后搭建了该套系统,并成功对该系统进行了时空对准调试与验证,时间对准调节精度达48.1 fs。经简单改进后,该系统可作为自由电子激光三维成像装置的离线对准系统,用于其离线对准调节。

Theoretical simulation and experimental study on double white light interference system

Background: To achieve three-dimensional (3D) imaging of general specimen on free electron laser, a device called double-beam 3D imaging device based on single shot free electron laser (FEL) pulse is being built, which will be used on Shanghai soft X-ray FEL. Visible light is planned to adopt on this imaging device for achieving offline space and time alignment. Purpose: This study aims to achieve offline space and time alignment and build an offline alignment system for 3D imaging device based on double-beam white light interference. Methods: Beam splitter prism, charge coupled device and other facilities were used to build this offline alignment system. Based on the wave optics theory, theoretical simulation and verification were performed by MATLAB programming. Results:Space and time alignment was achieved in the double-beam white light interference system. Regulation precision of time alignment was 48.1 fs. Conclusion: After simple improvement, the double-beam white light interference system can be used on 3D imaging device as an offline alignment system in the future.