自由电子激光被称为第4代先进光源，是帮助人类探索物质微观世界的最先进的研究工具，在能源、物理、化学、材料、生物等多个学科领域具有变革性的推动作用。基于可调极紫外相干光源的综合实验研究装置（简称"大连相干光源"）的成功研制，填补了中国在这一领域的空白，有望成为推动中国科技实现跨越式发展的"利器"。介绍了大连相干光源的研制背景和国内外的发展现状，阐述了装置成功研制的意义，并展望了未来的应用前景。
Free electron laser (FEL), called the fourth advanced light source, is the most advanced experimental device to explore the microscopic world. It has a transformative driving effect on many subjects, such as energy, physics, chemistry, materials, biology, etc. With the successful research of "comprehensive experimental research equipment based on tunable EUV coherent light source (Dalian Coherent Light Source, DCLS)", China's vacancy in this area has been filled. DCLS could be expected to be the edge tool to promote the development of science and technology in China. This paper briefly reviews the research background of DCLS and the development status of FEL at home and abroad, then states the significance of the successful research of this equipment, and finally highlights its application prospect.
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