Optical surfaces represented by second-degree polynomials (quadratic or conics) are ubiquitous in optics. We revisit the equations of the conic shapes in the context of grazing incidence optics, gathering together the curves commonly used in x-ray instruments and synchrotron beamlines. We present the equations for paraboloids, ellipsoids, and hyperboloids in a common and consistent notation. We develop the transformations from centered systems that are commonly used to describe conics and their axes of symmetry, to local coordinate systems centered on the off-axis mirror surfaces. The equations presented are directly applicable to ray tracing, fabrication, and metrology calculations. They can also be used to study misalignments, movement tolerances, and aberrations of optical surfaces.
A new algorithm to perform coherent mode decomposition of the undulator radiation is proposed. It is based in separating the horizontal and vertical directions, reducing the problem by working with one-dimension wavefronts. The validity conditions of this approximation are discussed. Simulations require low computer resources, and run interactively in a laptop. We study the focusing with lenses of the radiation emitted by an undulator in a fourth-generation storage ring (EBS-ESRF). Results are compared against multiple optics packages implementing a variety of methods for dealing with partial …
The deep ultraviolet, the bandgap region of dielectrics, is not readily accessible for established methods of ultrafast spectroscopy. Here, a miniature beamline, where a tailored deep ultraviolet field is used immediately after the noncollinear generation without subsequent optical elements, is introduced for transient absorption and dispersion spectroscopy. The near-bandgap region of diamond in the presence of a few-femtosecond pump pulse is explored where the delayed dynamical Franz-Keldysh effect and the almost instantaneous optical Kerr effect coexist.
Flux as well as spatial and angular resolution for a microbeam small-angle x-ray scattering set-up comprising Laue optics and multiple focusing elements are modeled within five-dimensional phase space analysis. A variety of x-ray optics configurations for highest angular resolution and for highest spatial resolution are analyzed.
We consider different approaches to simulate a modern X-ray beamline. Several methodologies with increasing complexity are applied to discuss the relevant parameters that quantify the beamline performance. Parameters such as flux, dimensions and intensity distribution of the focused beam and coherence properties are obtained from simple analytical calculations to sophisticated computer simulations using ray-tracing and wave optics techniques. A latest-generation X-ray nanofocusing beamline for coherent applications (ID16A at the ESRF) has been chosen to study in detail the issues related to hi…
The SASE3 soft X-ray beamline at the European XFEL has been designed and built to provide experiments with pink or monochromatic beam in the photon energy range 250 eV - 3000 eV. Here, we focus on the monochromatic operation of the SASE3 beamline and report on design and performance of the SASE3 grating monochromator. The unique capability of an FEL source to produce short femtosecond pulses of high degree of coherence challenges the monochromator design by a demand to control both photon energy and temporal resolution. The aim to transport close to transform-limited pulses poses very high dem…
In this work, we measure and model tilted x-ray refractive lenses to investigate their effects on an x-ray beam. The modelling is benchmarked against at-wavelength metrology obtained with x-ray speckle vector tracking experiments (XSVT) at the BM05 beamline at the ESRF-EBS light source, showing very good agreement. This validation permits us to explore possible applications of tilted x-ray lenses in optical design: we demonstrate that tilting 1D lenses around their focusing direction can be used for fine-tuning their focal length with possible applications in beamline optical design.
Illuminating or imaging samples from a broad angular range is essential in a wide variety of computational 3D imaging and resolution-enhancement techniques, such as optical projection tomography (OPT), optical diffraction tomography (ODT), synthetic aperture microscopy, Fourier ptychographic microscopy (FPM), structured illumination microscopy (SIM), photogrammetry, and optical coherence refraction tomography (OCRT). The wider the angular coverage, the better the resolution enhancement or 3D resolving capabilities. However, achieving such angular ranges is a practical challenge, especially whe…
The classification of bandstructures by topological invariants provides a powerful tool for understanding phenomena such as the quantum Hall effect. This classification was originally developed in the context of electrons, but can also be applied to photonic crystals. In this paper we study the topological classification of the refractive index surfaces of two-dimensional photonic crystals. We consider crystals formed from birefringent materials, in which the constitutive relation provides an optical spin-orbit coupling. We show that this coupling, in conjunction with optical activity, can lea…
Reconstruction of a conic-section surface from autocollimator-based deflectometric profilometry
我们提出了一种描述我们的方法来处理一组基于自准直仪的偏转仪1维线扫描采取了一个大的光学表面，并将它们重建到一个最适合的圆锥截面表面。我们的任务的挑战是，每个线扫描是在一个不同的（未知的）坐标参考系相对于其他线扫描的集合。这个问题的出现是由于偏转仪中使用的自准直仪的有限角度测量范围以及需要在更大范围内进行测量;这导致在每次扫描之间被测量的光学器件被旋转（俯仰和滚动）以使自准直仪回到测量范围内，因此每次扫描都在不同的坐标系中进行。我们描述了一种方法，使用6 N +2维优化（其中N是跨镜扫描线的数量），该方法使用基于梯度的非线性最小二乘拟合与多起点全局搜索策略相结合，以找到最佳拟合表面。仔细制定的问题，需要减少数值噪声，并允许例程收敛到所需的精度的解决方案。
Development of an Extensible Unified Control System Using the STARS Framework and Common Commands for Detector Control
Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK)（高能加速器研究机构物质结构科学研究所）；Materials Structure Science Program, Graduate Institute for Advanced Studies, Graduate University for Advanced Studies (SOKENDAI)（高级研究大学物质结构科学项目研究生院）；Graduate School of Pure and Applied Sciences（理学院研究生院）
Motivated by recent experimental initiatives, such as at the Helmholtz International Beamline for Extreme Fields (HIBEF) at the European X-ray Free Electron Laser (XFEL), we calculate the birefringent scattering of x-rays at the combined field of two optical (or near-optical) lasers and compare various scenarios. In order to facilitate an experimental detection of quantum vacuum diffraction and birefringence, special emphasis is placed on scenarios where the difference between the initial and final x-ray photons is maximized. Apart from their polarization, these signal and background photons m…
All-diamond optical assemblies for a beam-multiplexing X-ray monochromator at the Linac Coherent Light Source
最近在直线加速器相干光源（LCLS）上实现的双晶金刚石（111）单色器能够将初级X射线光束分成粉红色（透射）和单色（反射）分支。厚度为100 μ m的第一单色晶体提供足够的X射线透射率，以使两条光束线能够同时操作。在这里，我们报告的设计，制造和X射线表征的第一和第二（300微米厚）的晶体中使用的单色器和光学组件持有这些晶体。每个晶体板具有约5 × 2 mm2的区域，具有低缺陷浓度，足以用于LCLS处的X射线光学器件。保持晶体的光学组件被设计成提供在刚性基板上的安装并使安装引起的晶体应变最小化。使用双晶X射线形貌术评估了诱导应变，发现在晶体的5 X 2 mm 2工作区域上诱导应变很小。
