Effects of plane mirror thermal load on variable included angle plane-grating monochromator resolution
-
摘要: 针对变包含角平面光栅单色器前置平面镜(PM)受热负载而导致的单色器分辨率降低问题,提出优化聚焦常数(Cff)补偿分辨率的方法。首先,计算不同Cff值时PM的热功率吸收谱,在此基础上对镜面热负载进行热-结构耦合分析,得到不同热负载时PM表面热变形的变化量;然后,结合理想分辨率公式和光线追迹软件求出加热负载的单色器分辨率;最后,优化Cff实现分辨率的补偿。研究结果表明,以软X射线谱学显微光束线站为例,当出射光能量为1 000 eV时,将Cff由1.8优化至1.84,单色器分辨率即可与无热负载时的相同,该优化方法可有效补偿单色器分辨率的降低。
-
关键词:
- 变包含角平面光栅单色器 /
- 热负载 /
- 聚焦常数 /
- 分辨率 /
- 斜率误差
Abstract: In synchrotron radiation beamlines, the increasing light flux will lead to more thermal load on optical elements. The thermal load on the Plane Mirror(PM) of variable included angle plane-grating monochromator will decrease the resolution. This paper proposes a method to recover the resolution by optimizing the value of focusing constant(Cff). Firstly, the absorption spectra of thermal power with different values of Cff are obtained by calculation. Then thermo-mechanical analysis of PM is conducted to get variable deformations on PM with different thermal power. Secondly, the resolution is calculated by combining the function of ideal resolution and the software of ray tracing. Finally, the resolution is compensated by optimizing Cff. The result indicates that taking the soft X-ray spectroscopy micro beam line station of SSRF for example, the resolution can be improved by changing the value of Cff from 1.8 to 1.84 when the photon energy is 1 000 eV. So optimizing the value of Cff is an effective way to recover the decreased resolution induced by thermal power on PM. -
[1] 渡辺诚, 佐藤繁.同步辐射科学基础[M]. 上海:上海交通大学出版社, 2010. WATANABE M, SATO S. Introduction to Synchrotron Radiation Research[M]. Shanghai:Shanghai-jiaotong University Press, 2010.(in Chinese) [2] 唐福元. 同步辐射的发现、特性及其应用领域的开拓[J]. 物理与工程, 2004, 14(3):34-39. TANG F Y. Synchronizedradiation:Itsdiscovery, feature and exploitation[J]. Physics and Engineering, 2004, 14(3):34-39.(in Chinese) [3] REININGER R, CASTRO A D. High resolution, large spectral range, in variable-included-angle soft X-ray monochromators using a plane VLS grating[J]. Nuclear Instruments and methods in Physics Research A, 2005, 538:760-770. [4] ANDREAS K F. Third-generation synchrotron radiation X-ray optics[J]. Facility. Stru, 1996, 4(2):121-125. [5] PETERSEN H, JUNG C, HELLWIG C. Review of plane grating focusing for soft X-ray monochromators[J]. Rev. Sci. Instrum., 1995, 66(1):1-14. [6] KANTA O, JIN H O, KOJI H. Performance of the high-resolution high-flux monochromator for bending magnet beamline BL-1C at the Photon Factory[J]. Nuclear Instruments and Methods in Physics Research A, 2001, 467-468:573-576. [7] 马磊, 卢启鹏, 彭忠琦. 谱学显微光束线光斑水平漂移分析与检测[J]. 光学 精密工程, 2012, 20(3):514-519. MA L, LU Q P, PENG ZH Q. Analysis and test of light spot transversal transfer of spectromicroscpic beamline[J]. Opt. Precision Eng., 2012, 20(3):514-519.(in Chinese) [8] WARWICK T, CAMBIE D. A variable-included-angle plane-grating-monochromator on an undulator for spectroscopy and microscopy at the Advanced Light Source[J]. Nuclear Instruments and Methods in Physics Research A, 2001, 1:467-468. [9] 马磊. 变包含角平面光栅单色器关键技术与检测方法研究[D].北京:中国科学院大学, 2012. MA L. Research on the key technologies and the performance measuring for VAPGM[D]. Beijing:University of the Chinese Academy of Sciences, 2012.(in Chinese) [10] PETEERSEN H. The plane grating and elliptical mirror:A new optical configuration for monochromators[J]. Optics Communications, 1982, 40(6):402-406. [11] 高飒飒, 卢启鹏, 彭忠琦, 等. X射线干涉光刻偏转聚焦系统热载影响与分析[J]. 光学学报, 2012, 32(12):1234001(1-7). GAO S S, LU Q P, P ZH Q, et al.. Analysis of heating effect on XIL deflection focus system[J]. Acta Optica Sinica, 2012, 32(12):1234001(1-7).(in Chinese) [12] MU B ZH, WANG ZH SH, YI SH ZH. Study of X-ray Kirkpatrick-Beaz imaging with single layer[J]. Chin. Opt. Lett., 2009, 7(5):452-454. [13] 王纳秀. 同步辐射光束线热缓释技术研究及冷却技术的应用[D].上海:中国科学院上海应用物理研究所, 2006. WANG N X. Research on cooling technique of sr beamline components and application of cooling technique[D]. Shanghai:Shanghai Institute of Applied Physics, Chinese Academy of Sciences, 2006.(in Chinese) [14] CARPENTIER P, ROSSAT M, CHARRAULT P. Synchrotron monochromator heating problem, cryogenic cooling solution[J]. Nuclear Instruments and Methods in Physics Research A, 2001, 456:163-176. [15] 李云, 邢廷文. 采用非均匀有理B样条曲面延展光学元件面形误差[J]. 光学学报, 2012, 32(7):0722001. LI Y, XING T W. Surface error of optical components extended with non-uniform rational B-spline surface[J]. Acta Optica Sinica, 2012, 32(7):0722001.(in Chinese) [16] 余景池, 郭培基, 孙侠菲, 等. 波差与表面斜率误差评价方法的讨论[J]. 光学技术, 2001, 27(6):543-544. YU J CH, GUO P J, SUN X F. Discussion of wavefront error and slope error of the surface on the assessment method[J]. Optical Technique, 2001, 27(6):543-544.(in Chinese) [17] 王惠云, 吕丽军. X射线光学系统的光线追迹[J]. 光学 精密工程, 2000, 8(2):110-114. WANG H Y, LV L J. Raytracing of X-ray optical system[J]. Opt. Precision Eng., 2000, 8(2):110-114(in Chinese) [18] 唐家德. 基于MATLAB的非线性曲线拟合[J]. 计算机与现代化, 2008, 6:15-19. TANG J D. Nonlinear curve fitting based on MATLAB[J]. Computer and Modernization, 2008, 6:15-19.(in Chinese)
点击查看大图
计量
- 文章访问数: 1397
- HTML全文浏览量: 231
- PDF下载量: 586
- 被引次数: 0