Exclusive: Large Experimental Equipment and Planning in Light, Cosmic Ray and Space Study
								
							
                        		SUN Yang, ZHANG Weiqing, YANG Xueming
                        	
							
							
							
								
                            	
                            
                            
							
	                         	
	                         	
	                         	
	                         	
	                         	
	                         	
	                         	
	  							
	                         
							
								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.