一种用于软X射线激光去相干的单玻璃管光学透镜设计  

Design of a single glass tube optical lens for soft X-ray laser decoherence

作　　者：袁天语 邵尚坤 孙学鹏 李惠泉 华陆 孙天希[1,2] Yuan Tian-Yu;Shao Shang-Kun;Sun Xue-Peng;Li Hui-Quan;Hua Lu;Sun Tian-Xi(Key Laboratory of Beam Technology of the Ministry of Education,College of Nuclear Science and Technology,Beijing Normal University,Beijing 100875,China;Institute of Radiation Technology,Beijing Academy of Science and Technology,Beijing 100875,China)

机构地区：[1]北京师范大学核科学与技术学院,射线束技术教育部重点实验室,北京100875 [2]北京市科学技术研究院辐射技术研究所,北京100875

出　　处：《物理学报》2023年第3期85-91,共7页Acta Physica Sinica

基　　金：国家重点研发计划(批准号:2021YFF0701202);国家自然科学基金(批准号:11875087,12105020)资助的课题。

摘　　要：激光具有亮度高、单色性好、高相干性及方向性好的优势,然而在激光成像、激光加工等场景只想利用其高亮度或高单色性,高相干性导致的干涉效应会影响和限制其应用效果.通过模拟计算的方法,设计了一种针对软X射线激光去相干的新型单玻璃管光学透镜.模拟结果显示,针对波长为10 nm、束腰半径为1.25 mm的软X射线激光光束,透镜入口端内直径5 mm、出口端内直径0.6 mm、长度15 cm的单玻璃管光学透镜在有效降低软X射线激光光束相干度的同时,在出口处获得了发散度为30—50 mrad的出射光束,相应的传输效率为78%,光强增益为52.74.针对波长不低于1 nm的激光光束,该型号的单玻璃管光学透镜能够将光束的传输效率保持在30%以上.本文还探讨了入射光能量和透镜长度对器件传输结果的影响.结果表明,根据全反射原理设计的单玻璃管光学透镜能够满足极紫外到X射线波长范围内激光去相干的应用需求,在X射线激光成像、激光加工等方面具有广泛的应用前景.Laser has the advantages of high brightness,good monochromaticity,high coherence and good directionality,however,in some cases such as laser imaging and laser processing where only its high brightness or high monochromaticity is desired,the interference effect caused by high coherence can affect and limit its effective applications.In this work,a new single glass tube decoherence lens(SGTDL)is designed for soft X-ray laser decoherence through the simulation calculations.The simulation results show that an SGTDL with an entrance diameter of 5 mm,exit diameter of 0.6 mm and a length of 15 cm can effectively reduce the coherence of the X-ray laser with a wavelength of 10 nm and a beam waist radius of 1.25 mm.At the same time,the exit beam with a divergence range of 30-50 mrad is obtained at the SGTDL’s exit,and the transmission efficiency and gain in power density of the SGTDL are 78%and 52.74,respectively.For a laser beam with a wavelength of up to 1 nm,this model of SGTDL can maintain the transmission efficiency of the beam at more than 30%.This work also discusses the influence of the X-ray laser energy and the SGTDL’s length on the transmission performances of the SGTDL.The results show that the SGTDL designed according to the total reflection principle can meet the application requirements for laser decoherence in a range from the extreme ultraviolet to X-ray wavelength,and has a wide application prospect in X-ray laser imaging,laser processing,etc.

关 键 词：软X射线激光 去相干 X射线光学器件 玻璃管全反射X射线光学器件 

分 类 号：O434.1[机械工程—光学工程] TN24[理学—光学]