High-speed measurements, particularly close to the velocity of light, have always been a great challenge in the field of experimental measurement. Although traditional high-speed measurement methods based on imaging technology can achieve millions of frames per second, they face the problem that the field of view decreases with an increase in the frame rate, which is difficult to overcome in a short period. In this study, a closed multi-exposure optical path is designed first based on a 600 ps pulse laser that realizes the continuous measurement of sub-light velocity and is not subject to the field of view. The path can also be adjusted with respect to time, accurate up to sub-nanoseconds. Second, it is found that the accuracy and resolution of the present method are related to the used pulse laser and camera. Once the performances of the pulse laser and the camera are improved, the corresponding range of measurement of the velocity can be improved further. Compared with traditional pumping technologies, the proposed technology achieves continuous velocity measurement with the utilization rate of laser energy as high as 100%. Finally, we use this novel optical system to determine the flux avalanche velocity of the YBa₂Cu₃O_7-x superconducting thin film, and a highest speed of 323.5 Km/s is obtained.

中文翻译：

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通过单个激光脉冲优化的多曝光光路，用于超高速测量

高速测量，特别是接近光速的测量，一直是实验测量领域的巨大挑战。尽管基于成像技术的传统高速测量方法可以每秒获得数百万个帧，但是它们面临的问题是，视场随着帧速率的增加而减小，这在短期内很难克服。在这项研究中，首先基于600 ps脉冲激光设计出闭合的多重曝光光路，以实现连续测量次光速且不受视野限制。该路径还可以相对于时间进行调整，精确到亚纳秒。其次，发现本方法的准确性和分辨率与所使用的脉冲激光器和照相机有关。一旦改善了脉冲激光器和照相机的性能，就可以进一步改善相应的速度测量范围。与传统的泵浦技术相比，该技术实现了连续速度测量，激光能量利用率高达100％。最后，我们使用这种新颖的光学系统确定YBa ₂ Cu ₃ O _{7- x}的通量雪崩速度 超导薄膜，最高速度为323.5 Km / s。