Synchrotron radiation sources have become brighter in recent years. In order to profit all this brilliance, optical surfaces of the beamlines must have slope errors below 1-2 microradians RMS. Thus, it is necessary to have accurate and repeatable measurements of these surfaces (plane, elliptical, toroid, etc.). In this work, a Fizeau interferometer is used for their characterization. The accuracy of the measurement is limited by quality of the reference surfaces of the interferometer. Lateral shearing technique is applied in order to remove the influence of the reference surfaces. This technique requires to use two or more images of the surface displaced each other. Then, systematic errors of the linear stage (guidance and positioning errors) become the limit for an accurate characterization. Different algorithms for the estimation and compensation of these systematic errors have been developed. They are based on the two dimensional redundancy of the data obtained from multiple measurements. In addition, algorithms to control the alignment of the setup have been developed and implemented in a stand-alone application. As a result, once errors introduced by the stage are controlled, an accurate characterization of the optical surfaces for beamlines is obtained. With this extended data analysis, the accuracy of the mirror characterization can be improved with independence of the quality of the reference optics of the interferometer.

The major problem of measurement of a power spectral density (PSD) distribution of the surface heights with surface profilometers arises due to the unknown Modulation Transfer Function (MTF) of the instruments. The MTF tends to distort the PSD at higher spatial frequencies. It has been suggested [Proc. SPIE 7077-7, (2007), Opt. Eng. 47 (7), 073602-1-5 (2008)] that the instrumental MTF of a surface profiler can be precisely measured using standard test surfaces based on binary pseudo-random (BPR) patterns. In the cited work, a one dimensional (1D) realization of the suggested method based on use of BPR gratings has been demonstrated. Here, we present recent achievements made in fabricating and using two-dimensional (2D) BPR arrays that allow for a direct 2D calibration of the instrumental MTF. The 2D BPRAs were used as standard test surfaces for 2D MTF calibration of the Micromap^TM-570 interferometric microscope with all available objectives. The effects of fabrication imperfections on the efficiency of calibration are also discussed.

A new concept profiler has been developed to measure items such as asymmetric and aspheric profiles with a small radius curvature lens and mirrors. In this study, the normal vectors at each point on the surface are determined by a reflected light beam that returns along exactly the same path as the incident beam. In order to measure a small radius curvature, a compact measuring instrument was redesigned according to the above principle of the measuring method employed. The instrument is 1200 mm (W) × 1000 mm (H) × 1500 mm (V). The measurement of normal vectors of a spherical lens, which has a small f number such as a 25 mm radius curvature, has been demonstrated with a measuring accuracy for the normal vector of 0.1 μrad. The surface gradient at each point is calculated from the normal vector, and the surface profile is obtained by integrating the gradient. When integrating the gradient, measured position accuracy should be in the order of 10 nm. They were obtained by self-calibration techniques that have already developed by the authors. In this paper, we discuss methods of calculating absolute radius curvature and deviation from the ideal surface profile.

We have used a direct optical measurement of the distortion of the first silicon crystal of the CHESS A2 monochromator. The total X-ray power absorbed by the crystal was in the range of 2 to 190 Watts. The X-ray powers measured by a bolometer were in good agreement with the XOP calculations. In-situ optical measurements were used to measure the deformation of the crystal under the heat load between a 3-15° angle of incidence. Simultaneously, ANSYS modeling of the effect of the heat load on the monochromator crystal with the cooling assembly was done. The measured slope error and the surface deformation profiles were in good agreement with the ANSYS simulations. A rocking curve method was used to measure the effect of a heat load on the diffraction properties of the monochromator for a range of beam-defining slit widths. We have found a good correlation between the FWHM of the rocking curves and the slope errors from the optical measurements.

We demonstrate a novel experimental method for improvement of efficiency of structural surface modification of various solids (PMMA, amorphous carbon) achieved by simultaneous action of XUV (21.6 nm), obtained from high-order harmonic generation (HHG), and VIS-NIR (410/820 nm) laser pulses. Although the fluence of each individual pulse was far below the surface ablation threshold, very efficient and specific material modification was observed after irradiation by a single or a few shots of mixed XUV/VIS-NIR radiation. We also report results on comprehensive characterization of ultrafast coherent X-ray beamline at Prague Asterix Laser System (PALS). The beamline is based on 1 kHz, table-top, high-order harmonic generation source capable to deliver fully coherent beam in the 30 nm spectral range. Ti:sapphire (810 nm, 1 kHz) laser pulses with a duration of 35 fs and energy 1.2 mJ have been focused into gas cell containing conversion medium (Ar). To achieve highly efficient HHG we will apply the technique of guided laser pulses. Source parameters were investigated.

Piezoelectric actuators are widely employed in adaptive optics to enable an actively controlled mirror surface and improve the optical resolution and sensitivity. Currently two new prototype adaptive X-ray optical systems are under development through the Smart X-ray Optics project in a UK based consortium. One proposed technology is micro-structured optical arrays (MOAs) which uses aligned micro-channels structures obtained by deep silicon etching using both dry and wet techniques and bonded piezoelectric actuators to produce a micro-focused X-ray source for biological applications. The other technology is large scale optics which uses a thin shell mirror segment with 20-40 bonded piezo-actuators for the next generation of X-ray telescopes with an aim to achieve a resolution greater than that currently available by Chandra (0.5"). The Functional Materials Group of Birmingham University has the capability of fabricating a wide range of piezo-actuators including, for example, unimorph, bimorph and active fibre composites (AFC) by using a viscous plastic processing technique. This offers flexibility in customising the shapes (from planar to 3-D helix) and feature sizes (>20 μm) of the actuators, as well as achieving good piezoelectric properties. PZT unimorph actuators are being developed in this programme according to the design and implementation of the proposed mirror and array structures. Precise controls on the dimension, thickness, surface finishing and the curvature have been achieved for delivering satisfactory actuators. Results are presented regarding the fabrication and characterisation of such piezo-actuators, as well as the progress on the large optic and MOAs prototypes employing the piezo-actuators.

The Smart X-Ray Optics (SXO) project comprises a U.K.-based consortium developing active/adaptive micro-structured optical arrays (MOAs). These devices are designed to focus X-rays using grazing incidence reflection through consecutive aligned arrays of microscopic channels etched in silicon. The silicon channels have been produced both by dry and wet etching, the latter providing smoother channel walls. Adaptability is achieved using piezoelectric actuators, which bend the device and therefore change its focal distance. We aim to achieve a 5 cm radius of curvature which can provide a suitable focal length using a tandem pair MOA configuration. Finite Element Analysis (FEA) modelling has been carried out for the optimization of the MOA device design, consider different types of actuators (unimorph, bimorph and active fibre composites), and different Si/piezoelectric absolute and relative thicknesses. Prototype devices have been manufactured using a Viscous Plastic Processing Process for the piezoelectric actuators and dry etched silicon channels, bonded together using a low shrinkage adhesive. Characterisation techniques have been developed in order to evaluate the device performance in terms of the bending of the MOA channels produced by the actuators. This paper evaluates the progress to date on the actuation of the MOAs, comparing FEA modelling with the results obtained for different prototype structures.

Modern polishing methods of ion-beam milling, and single atom removal techniques are beginning to allow the fabrication of arbitrary surface shapes for reflecting grazing incidence optics. Moreover, the total expense of fabrication, coating, measuring, mounting, aligning, cooling, and surrounding the optic with vacuum make the reduction of optical part count attractive for the latest generation x-ray sources, not even considering potential effects on the scattering and reflective losses of the radiation. These two developments converge to effectively suggest the question of what surface would be the optimally de-magnifying surface to replace a toroid illuminated by a wave cylindrical in the sagittal direction if the sag of the single surface were determined by a function, and not constrained to be a typical optical shape. To address this we derive a simplified case of the formalism of Chrisp, using the classical optical path function approach of Fermat to give a power series calculation of this best surface. This surface, the "diaboloid," would in principle earn its name by its, at least ab initio, consideration of being very difficult to manufacture. We show an example of improvement this surface would provide.

We have been developing a thin-foil-nested X-ray telescope (XRT) for the Japanese X-ray astronomy satellites since ASCA launched in 1993. The thin-foil-nested XRT is advantageous in realizing high throughput with a light weight, whilst its angular resolution is poorer than other mirrors using, for example, a polished thick glass substrate onboard Chandra. We have investigated causes of image degradation of our XRT, and have identified them as figure error and positioning error of the reflectors. Since the latter dominates the entire error budget, we first attempted to improve the positioning error, and adopted the following two methods. First, we substituted an alignment plate for the alignment bar. The alignment plate incorporates the independently movable four alignment bars adopted for ASCA and Suzaku into a single plate. In practice, we allocated a pair of the plate in each slot, and after inserting all the reflectors, we shifted one of the plates radially to tightly hold the reflectors. Second, we have manufactured a partially replicated foil in which reflecting material (Au) is not applied to the axial edges of the foils in order to control the foil position by the edges of the reflectors whose thickness variation is within 2 μm. After these improvements on the positioning error, we moved onto the figure error issue. With X-ray and laser profilometer measurements, we found that the figure error increased in a area closer to the azimuthal edges of the reflector. After considerable struggle for improvement, we finally decided to produce a long reflector and to cut both azimuthal edges. Thanks to these new devices, we have reduced the positioning error from 1.5 arcmin to 0.66. Furthermore, we have successfully produced 40-pairs of reflectors whose figure error is less than 0.8 arcmin. Incorporating these reflectors into a mirror housing, we have measured the XRT performance in the 30 m beamline facility at ISAS/JAXA, and confirmed to achieve an angular resolution of 1.08 arcmin in half-power diameter. The effective area is measured to be 14.0 cm², which is ~90% of the designed value. Note that this number is significantly enhanced from ~80% in the Suzaku XRT, which is a by-product of the improvement of the angular resolution.

Montel (nested) Kirkpatrick-Baez mirrors can focus X-ray and neutron beams with larger divergences into small beams than is possible with standard (sequential) Kirkpatrick-Baez optics. They also provide for a more compact focusing system and higher fluxes into small beams than with current alternatives. These attributes make Montel optics critically important for both achromatic neutron and X-ray focusing. Here we describe design rules that optimize mirror performance under various constraints, including diffraction-limited, and flux-limited focusing. We also describe first tests of optical designs that employ nesting as a way to improve neutron microfocusing optics and suggest future directions for X-ray nanofocusing optics.

An absolute efficiency measurement technique for Fresnel zone plates using an electron impact micro-focus laboratory X-ray source (Lα line of Tungsten at 8.4 KeV) is demonstrated. A quasi-monochromatic x-ray image of a zone plate was obtained employing a pair of copper and cobalt filters. Applying this method to zone plates optimizes the zone plate fabrication process and provides the ability to explore zone geometry to achieve the best possible efficiency. Several zone plate parameters were tested with first order efficiency measuring from 1% to 29%.

Most applications of x-ray multilayers at modern synchrotron sources require a precise control of the d-spacing over large areas. The grazing incidence geometry causes a long beam footprint. Curved multilayer optics may need steep thickness gradients in order to reflect the full beam at constant photon energy. The tolerable thickness error is far below the intrinsic energy resolution of the multilayer Bragg peak, which is of the order of 1% or less. The recently commissioned ESRF multilayer deposition system can coat surfaces of up to 1000mm long and 150mm wide with a precise thickness distribution. The local particle flux is controlled by both linear motion of the substrates and masking of the particle sources. The thickness profiles are estimated using a numerical model. Corrections can be applied to suppress minor errors. Recent results illustrate both the potential and the limitations of the available deposition technology. A description of present and future applications at 3rd generation synchrotron sources complements this work.

We report on recent progress in developing diffraction gratings which can potentially provide extremely high spectral resolution of 10⁵-10⁶ in the EUV and soft x-ray photon energy ranges. Such a grating was fabricated by deposition of a multilayer on a substrate which consists of a 6-degree blazed grating with a high groove density. The fabrication of the substrate gratings was based on scanning interference lithography and anisotropic wet etch of silicon single crystals. The optimized fabrication process provided precise control of the grating periodicity, and the grating groove profile, together with very short anti-blazed facets, and near atomically smooth surface blazed facets. The blazed grating coated with 20 Mo/Si bilayers demonstrated a diffraction efficiency in the third order as high as 33% at an incidence angle of 11° and wavelength of 14.18 nm. This work was supported by the US Department of Energy under contract number DE-AC02-05CH11231.

To study the action of shock wave in CH target, one-dimensional grazing incidence KBA microscope for 4.75keV energy was set up. Because of strong absorption in air, 4.75keV energy microscope can just work in vacuum. Accordingly, the alignment and assemblage will be very complicated and difficult. A special multilayer method, using double periodic multilayer, was proposed to solve this problem. This multilayer has high reflectivity not only for 4.75keV x-rays but also for 8keV x-rays at the same grazing incidence angle. It means 1D-KBA microscope has the same light trace for different working energies. Therefore, we can implement the alignment and assembly of 4.75keV system by the help of 8keV x-rays. Because 8keV x-rays is very easy produced by x-ray tube and has strong transmittability in air, the alignment and assemblage process became relatively easy. By now, we have finished the alignment experiment at 8keV and obtained imaging results. The performance is about 2-3μm resolution in 250μm field of view. It is coincide with the calculation.

X-ray sources according to the principle of the "free electron laser" (FEL), will in future, be able to provide bright radiation with pulses in the femtosecond range. Even nowadays, home-lab X-ray sources with very short pulses in the sub-picosecond range are already available for lab experiments. These laser-based sources need different kinds of optics to direct the emitted X-rays onto the samples. On the one hand, the optics should transfer as much flux as possible and on the other hand, the brilliance and timestructure of the source should not be reduced too much. These requirements are fulfilled with 2-dimensional beam shaping multilayer optics. Their design, production and their influence on the shape of the X-ray beam will be explained in this contribution. The optics consist of bent substrates with shape tolerances below 100 nm, upon which multilayers are deposited with single layer thicknesses in the nanometer range and up to several hundreds of pairs of layers. Furthermore, these multilayers were designed with lateral thickness gradients within ± 1% deviation of the ideal shape. This means that a deposition precision in the picometer range is required. We use magnetron sputtering methods for deposition, optical profilometry in order to characterize the shape of the optics and X-ray reflectometry to characterize the multilayers.

The spectral range of 50 to 115 nm in the extreme ultraviolet (EUV) is characterized by the high absorption and low normal incidence reflectance of most materials, which make difficult the development of high reflectance multilayer mirrors at normal incidence angles. The availability of efficient mirrors would have a great impact on the performance of EUV space telescopes and other EUV instruments at these wavelengths. In order to obtain high normal-incidence reflectance coatings, it is necessary to find materials with absorption as low as possible at 50 - 115 nm. Recently, lanthanides and close elements have attracted the attention of researchers because of their relatively low absorption at bands in the EUV, and several studies on the optical constants of lanthanides in the EUV have been published. As a result of these investigations we have identified those lanthanides which better match the low absorption requirement at wavelengths in the 50 - 115 nm range. In this work we present the use of the lanthanide Yb combined with other materials and protective capping layers in multilayers designed to have a reflectance maximum at a wavelength selected within the spectral range of 50 to 95 nm. Experimental results for the case of a multilayer composed of Yb, Al and SiO layers confirm the adequacy of this approach, providing a peak reflectance of 0.276 at 80 nm with FWHM of 14.5 nm for samples not exposed to the atmosphere. A decrease in peak reflectance from 0.276 to 0.209 was observed after 2 years of storage in a dessicator.

FERMI@Elettra is a Free Electron Laser (FEL) user facility currently under construction at Sincrotrone Trieste, Italy. It will provide a spatial coherent transform-limited beam in the sub-ps regime, covering the wavelength range from 100 nm to 3 nm with the goal of 1 nm (by using third harmonics). The transform-limited beam is supposed to have a natural energy bandwidth of the order of 50-100 meV. Nevertheless, one of the three future beamlines, the one dedicated to Low Density Matter (LDM) studies, needs a monochromator to clean the signal. It must cover the whole wavelength range with eventual omission of the lower energy part. We will report the design of a fixed included angle monochromator employing three gratings. The optical system will be described, and particular attention will be given to the constraints like the pulse broadening, the focus displacement and, of course, the flux. Engineering constraints and manufacturers tolerances also taken into account will be presented, too.

Spatial structure of a focused beam diffracted from crystals of different thickness was studied experimentally at the ESRF optical beamline BM5. The beam was focused by a planar parabolic refractive lens. Si (111) thick crystal and 8 μm and 50 μm thick perfect Si(111) crystals positioned between the lens and the focus were used as model samples. The structure of the beam was analyzed at the focus of the lens by using a knife edge scan and a high-resolution CCD camera. The broadening of the focused beam due to the extinction effect was experimentally measured and compared with theoretical predictions. For a sufficiently thin crystal a second peak was experimentally observed which is due to the reflection from the back surface. We found also that the spatial structure depends on whether the crystal diffracts strongly (dynamically) or weakly (kinematically). In the later case, both surfaces of the crystal effectively reflect as mirrors with the reduced reflectivity and the relative intensity of the two peaks is determined by absorption. Theoretical simulations show excellent agreement with experiment.

The increasing importance of X-ray diffractometry with one- and two-dimensional detectors for materials research has lead to a rising demand for highly intense X-ray sources enabling the analysis of very small and weakly scattering samples in the home-lab within a reasonable time frame. As a result, various microfocusing sealed tube X-ray sources with focal spot sizes below 50μm are now available. Potential applications of the low-maintenance, high-brilliance microfocus source IμS, which are equipped with different two-dimensional beam shaping multilayer optics, will be shown. With the instrumentation that is now available, more and more crucial measurements like gracing incidence small angle X-ray scattering or stress and pole figure measurements can be carried out in the lab, and even in-situ during dynamic processes. Some ideas on new instrumental set-ups for customized X-ray analytics will also be shown.

The gain spectrum in a gated multichannel intensifier output depends on the gain and spatial averaging. The spectrum affects the minimum signal that can be detected as well as the signal to noise in the detected images. We will present data on the gain-spectrum for the GXD detector, a gated x-ray detector to be used at the National Ignition Facility. The data was recorded on a cooled CCD detector, with an x-ray gating time of approximately 75 ps, selected from a range of 0.2 and 1 ns electrical pulse width determined by pulse forming modules were also used. The detector was characterized at the TRIDENT laser facility, using a 2.4 ns long x-ray at 4.75 keV. The x-rays were generated by the interaction of the focused Trident laser beam with a Titanium target.

Paper is devoted to further evolution of the concept of ultra-high density hard x-ray storage media - a radically new x-ray- based optical data storage nanotechnology with terabit-scale digital data density per square centimeter of each storage layer of the memory disk. Forthcoming hard x-ray optical data read-out devices will use an ultra-high density information carrier named x-ray optical memory (X-ROM), which consists of crystalline wafer with the generated sub-surface amorphous nanometer-size reflecting speckles of x-ray high-reflectivity material. X-ROM is designed for long-term archiving of the large volumes of information and digital data handling via read-out systems operating on x-ray wavelength optics. Digital data read-out procedure from X-ROM is performed via grazing-angle incident x-ray micro beam. X-ray-based optical data storage system detects data by measuring changes in x-ray micro beam intensity reflected from the various surface points of data storage media. Grazing-angle incident x-ray configuration allows the handling of data from very large surface area of X-ROM disk and, consequently, the data read-out speed is much faster than in optical data read-out systems. Aim of paper is detailed evaluation of storage data-layer's effective thickness best fitted for a digital data read-out procedure. Penetration depths of non-homogeneous x-ray wave fields inside crystalline substrate and amorphous speckles of X-ROM are investigated theoretically in case of grazing-angle incidence x-ray backscattering diffraction (GIXB) applied in specular beam suppression mode. It is possible to reduce the effective thickness of data storage layer to a value of less than a single-bit linear size i.e. to reduce effective thickness up to 10 nm, according to performed evaluations.

The NSLS-II[1] program has a requirement for an unprecedented level of x-ray nanofocusing and has selected the wedged multilayer Laue lens[2,3] (MLL) as the optic of choice to meet this goal. In order to fabricate the MLL a deposition system capable of depositing depth-graded and laterally-graded multilayers with precise thickness control over many thousands of layers, with total film growth in one run up to 100μm thick or greater is required. This machine design expounds on the positive features of a rotary deposition system[4] constructed previously for MLLs and will contain multiple stationary, horizontally-oriented magnetron sources. A transport will move a substrate back and forth in a linear fashion over shaped apertures at well-defined velocities to affect a multilayer coating.

Zone plate [1] has been used as a focal lens in transmission X-ray microscope (TXM) optical system in recent decades [2, 3]. In TXM of NSRRC[4,5], the thickness of zone plate is about 900nm and the width of its out most zones is 50nm, which has a high aspect ratio 18. When zone plate is tilted, the image quality will be affected by aberration. Since the aspect ratio of zone plate is large, for incident beam, the shape of zone plate's transmission function will look different when zone plate is tilted. The both experimental and simulation result will be shown in this present. A five axes stage is designed and manufactured for the zone plate holder for three dimensional movement, tip and tilt. According to Fourier theory, we can calculate the wave distribution on image plane, if we know the original wave function, the distances between each element, and the transparencies of the sample and zone plate. A parallel simulation process code in MATLAB is developed in workstation cluster with up to 128Gbytes memory. The effects of aberration generated by tilt effect are compared from the experimental data and simulation result. A maximum tilt angle within the acceptable image quality is calculated by simulation and will be verified by experiment.

A high-precision slit for monochromatic x-rays has been developed as one of the standardized components in the undulator beamline at SPring-8. Advanced experiments such as x-ray micro-beam diffraction and x-ray scanning microscope using nano-beam require small, variable and accurate apertures. The newly developed slit has an aperture size ranging from 1 μm × 1 μm to 20 mm × 20 mm with a resolution of 0.5 μm in full step. Each blade is independently driven through bellows mounted on both sides of the vacuum chamber. A set of bellows prevents displacement of the blade by evacuation. Using this slit, we could improve the displacement from 20 μm to 1 μm. The positioning accuracy of the slit is 0.5 μm. The slits have been installed in the three beamlines at SPring-8.

This paper presents the design and implementation of focusing optical systems using total reflection mirrors that are customized into three hard x-ray beamlines for four experimental groups at SPring-8. First, for the BL46XU Engineering Science Research III beamline, we designed a vertical focusing mirror and a manipulator to create a high-intensity 20- μm focusing beam, that improves the sensitivity for hard x-ray photoemission spectroscopy. Second, for the BL39XU Magnetic Materials beamline, we designed two pairs of Kirkpatrick-Baez (KB) mirrors and corresponding manipulators for sub-micron focusing and 15 × 15 μm² high-intensity focusing; these were designed in order to use X-ray magnetic circular dichroism (XMCD) spectroscopy for two-dimensional high-resolution mapping of magnetism and XMCD experiments under high pressures (~10 GPa). Third, for the BL32XU RIKEN Targeted Proteins beamline, we designed KB mirrors for focusing at 1 × 1 μm²; these were designed for carrying out the structural analysis of microcrystal proteins in cooperation with RIKEN SPring-8 Center. These elliptical mirrors and manipulators are currently in the process of being manufactured, and their installation on the beamlines is underway. In this paper, we describe the design considerations, optimized design of the optical system, and installation progress on the beamlines.

Application of the x-ray scattering (XRS) technique for studying super-smooth surfaces such as Si wafers is discussed. The XRS method is demonstrated to enable quantitative evaluation of power spectrum density (PSD) functions and effective roughness of super-smooth surfaces. Within the calculation of PSD functions, comparative study between first-order vector perturbation theory (FOPT) and generalized Harvey-shack theory (H-S) is performed. First-order perturbation theory which is widely accepted and has been extensively validated even for large scattered and incident angles for "smooth" surfaces considers the scattering amplitude as a power series in the roughness height; its scattering diagram is related to the statistical parameters of surface roughness (PSD functions) in a very simple way (linear). Therefore, PSD functions can be uniquely and directly extracted from the measured data. However, generalized Harvey-shack theory considers that scattering behavior is characterized by a surface transfer function which relates the scattering behavior to the surface topography. With the grazing incident angle less than critical value about 0.22 degree, three Si wafers with rms roughness of 0.29nm, 0.46nm and 0.67nm are inspected by XRS (λ=0.154nm) method. The calculated values are all in a good agreement with the results obtained from Atomic force microscope (AFM). However, the difference resulting from the limits of applicability of the theories used in XRS data processing appears and be analyzed. Both of the theories are not only used for optical surface characterization, but also can allow accurate predictions of image degradation due to scattering effects in grazing X-ray telescopes. The experimental schemes are also analyzed.