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Takato Inoue, Yuka Nishioka, Satoshi Matsuyama, Junki Sonoyama, Kazuteru Akiyama, Hiroki Nakamori, Yoshio Ichii, Yasuhisa Sano, Xianbo Shi, Deming Shu, Max D. Wyman, Ross Harder, Yoshiki Kohmura, Makina Yabashi, Lahsen Assoufid, Tetsuya Ishikawa, and Kazuto Yamauchi, "Optimal deformation procedure for hybrid adaptive x-ray mirror based on mechanical and piezo-driven bending system", Review of Scientific Instruments 92, 123706 (2021), https://doi.org/10.1063/5.0070465., A hybrid deformable x-ray mirror consisting of a mechanical bender and a bimorph deformable mirror has been developed to realize adaptive optical systems, such as zoom condenser optics, for synchrotron-radiation-based x-ray microscopy. In the developed system, both bending mechanisms comprehensively contribute to the formation of the target mirror shape and can narrow the role of piezoelectric actuators, thereby enabling a more stable operation. In this study, the behavior of the bimorph mirror under the clamped condition was investigated, and the sharing of the deformation amount for each bending mechanism was optimized to minimize the amplitude of the voltage distribution of the bimorph mirror.

We have developed an X-ray zoom condenser optical system using deformable mirrors that can adjust the beam size by deformation of their shape. The shapes of deformable mirrors are changed by a combination of mechanical and piezoelectric bending. Large deformations up to third order polynomials are achieved by mechanical bending. More precise shapes are achieved by piezoelectric bimorph mirror. However, because both ends of the mirror are mechanically clamped, capability of deformation by piezoelectric bending is lower than that of free-standing piezoelectric bimorph mirrors. So, we propose a bending method that tunes the mechanical bending conditions to intentionally leave the optimized shape error to be easily compensated by the piezoelectric bending process.

Dielectric and elastic properties of aluminate-sodalite-type oxides, ${({\mathrm{Ca}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x})}_{8}{[\mathrm{Al}{\mathrm{O}}_{2}]}_{12}{(\mathrm{Mo}{\mathrm{O}}_{4})}_{2}$ with $x=1/16$ and 1/4, are investigated in the present study. A well-defined improper ferroelectric phase transition is demonstrated in the composition of $x=1/16$ by the onset of spontaneous strain and sharp anomalies in the dielectric and elastic responses around 600 K. As the Sr concentration increases to $x=1/4$, strong frequency dispersion appears in the dielectric and elastic responses, indicating that the system changes into a short-range ordered state. The dielectric and elastic anomalies are found to follow a single Vogel-Fulcher equation over a wide frequency range from ${10}^{\ensuremath{-}1}$ to ${10}^{6}\phantom{\rule{0.16em}{0ex}}\mathrm{Hz}$. The present results suggest an improper relaxor state at the composition of $x=1/4$, in which polar nanoregions form under spatially heterogeneous strain due to differences in the local coordination environments around Ca and Sr.

Production of over 600 ultra-smooth mirrors has been achieved by JTEC Corporation since 2006, which can be recognized as the evidence of large contribution to development of x-ray optics. To fabricate these mirrors, extremely high-accuracy surface shape measurement technology is necessary, therefore, RADSI, which is developed by Osaka University, has been applied to the manufacturing over the ages [1, 2]. In recent years, however, according to the growth of demand for a higher demagnification and a larger area light reception, surface curvature becomes steeper, thus, RADSI alone does not cover all mirrors. In order to resolve this matter, coordinate measuring machine (CMM) have been developed. In this study, the measurement performance of this CMM is discussed on the basis of the comparison with RADSI.

Various types of X-ray focusing optical systems are used at X-ray synchrotron radiation and free-electron laser facilities. However, these are designed for specific purposes and fixed optical parameters such as the numerical aperture (NA). Their lack of adaptability limits their application targets. In this research, we developed an X-ray adaptive focusing optical system which can control the beam size without moving the position of focus. The optical system consists of two deformable mirrors in one dimension. To vary the focused beam size, the NA is controlled by deforming the shape of the mirrors from concave to convex. The results will be presented along with the aberration properties estimated by ray trace and wave optical methods.

A 65-year-old man was admitted to our institution with vomiting and right flank pain. Computed tomography (CT) imaging showed a 21-cm retroperitoneal multilocular cystic tumor which had been identified four years previously. It had increased from 17 to 21 cm. The initial diagnosis was cystic lymphangioma because it was a clear cystic tumor without a boundary or a solid component in the first CT, but later CT revealed an unclear boundary with surrounding organs suggesting malignancy. We decided to resect the tumor because it was symptomatic and might be malignant. The tumor was then resected along with surrounding organs because invasion was suspected. Pathological findings indicated a diagnosis of cystic lymphangioma with chronic inflammation and confirmed complete resection of the tumor. The patient has remained free of recurrence at one year after surgery. This experience indicates that cystic lymphangioma should be completely resected to prevent recurrence.

In synchrotron radiation facilities and X-ray free electron laser facilities, beam size adjustment depending on the experimental condition and the sample size is necessary. Various types of X-ray focusing optical systems are used for beam conditioning. However, they are specially designed for specific purposes and optical parameters such as numerical aperture (NA) and focal length are fixed. This lack of adaptability has limited application targets. In this research, we are developing X-ray adaptive focusing optical system which can control the beam size without moving the position of the focus. The optical system consists of two deformable mirrors in one dimension. In order to control the focused beam size, the NA can be controlled by deforming the mirror shapes from concave to convex. When we want to achieve large NA, deform the upstream mirror into convex shape and spread the beam. The downstream mirror receives X-ray with full aperture and X-ray is focused at focal point. When we want to achieve small NA, deform the upstream mirror into a concave shape and narrow down the reflection area of downstream mirror. NA becomes small because reflection area of downstream mirror becomes narrow. One dimensional focusing experiment of large NA adaptive optical system was performed at SPring-8 as a demonstration. A focused beam with an intensity profile having a full width at half maximum of 134 nm was achieved at 10 keV. This is close to ideal beam size. In my presentation, I will explain details of adaptive focusing optics and deformable mirrors.

We describe the case of a patient with hyperammonemia owing to urinary tract infections. The patient, a 66-year-old-woman, was previously diagnosed with bilateral hydronephrosis. She was admitted to the emergency room with macrohematuria and bilateral lumbar pain, which persisted for 2 days. She was hospitalized with the diagnosis of pyelonephritis. Despite antibiotic treatment, she developed sudden disturbance in consciousness on the 2nd day of illness. To improve the hyperammonemia and metabolic acidosis, we initiated continuous hemodiafiltration (CHDF) and urinary drainage by bilateral nephrostomy, after which her consciousness improved, and she was discharged on day 19. For patients with urinary tract infections and who are unaware of disturbance in consciousness, it is important to consider that obstructive urinary tract infections can cause hyperammonemia.

A 48-year-old man with a history of cerebral infarction presented with gross hematuria. The patient's limping accompanies twisting trunk on his walking. The diagnosis was right upper ureteral stone. Prior to Extracorporeal shockwave lithotripsy (ESWL) ureteral stent was inserted. After the second ESWL ureteral stent was displaced upwardly without patient's unknown. Retrograde intrarenal surgery (RIRS) was performed for both removal of ureteral stent and fragmentation of residual stone. Spontaneously, post RIRS ureteral stent was migrated upwardly to the same position. Ureteral stent migration is uncommon. Twisting walk may cause the position of ureteral stent upwardly.

Ultra-bright and high-coherence X-rays are now being used in synchrotron radiation facilities and X-ray free electron laser facilities. X-ray focusing techniques are essential to take full advantage of these excellent X-ray light sources. To meet the strong demand, high-quality X-ray focusing optics have been developed owing to the advancement of ultraprecision machining and measurement. State-of-the-art refractive lenses [1], zone plates [2], and Laue lenses [3] can be used to achieve X-ray focusing to a spot a few tens of nanometers.

An adaptive X-ray mirror with shape controllability in a spatial wavelength range longer than 20 mm was developed, and we demonstrated its shape generation and focusing performance characteristics. The shape accuracy in a spatial wavelength range shorter than 20 mm, which cannot be adaptively figured, was controlled in advance offline. A pencil beam method for measuring the slope error and a phase retrieval method for precisely estimating the wavefront error were employed for online shape correction. A focal spot size of 120 nm, which is diffraction-limited, was realized, and the shape accuracy obtained nearly satisfied Rayleigh's quarter-wavelength criterion.

We fabricate ultra-precision mirrors, Osaka Mirror, for synchrotron facilities. In order to fabricate them, it is very important to measure mirror surface precisely. In respect of the importance, we use two kinds of metrology, RADSI and MSI, developed by Osaka University. We have delivered more than 300 mirrors to synchrotron facilities all over the world since 2006 and our mirrors have produced excellent results to many researchers. As the demand on one meter long mirrors has increased lately, we developed RADSI and MSI systems which are capable in precise measurement of such long mirrors.

A two-stage adaptive optical system using four piezoelectric deformable mirrors was constructed at SPring-8 to form collimated X-ray beams. The deformable mirrors were finely deformed to target shapes (elliptical for the upstream mirrors and parabolic for the downstream mirrors) based on shape data measured with the X-ray pencil beam scanning method. Ultraprecise control of the mirror shapes enables us to obtain various collimated beams with different beam sizes of 314 μm (358 μm) and 127 μm (65 μm) in the horizontal (vertical) directions, respectively, with parallelism accuracy of ~ 1 μrad rms.

X-ray science has greatly benefited from the progress in X-ray optics. Advances in the design and the manufacturing techniques of X-ray optics are key to the success of various microscopic and spectroscopic techniques practiced today. Here the generation of apodized X-ray illumination using a two-stage deformable Kirkpatrick–Baez mirror system is presented. Such apodized illumination is marked by the suppression of the side-lobe intensities of the focused beam. Thus generated apodized illumination was employed to improve the image quality in scanning X-ray fluorescence microscopy. Imaging of a non-isolated object by coherent X-ray diffractive imaging with apodized illumination in a non-scanning mode is also presented.

Unlike the electrostatic and electromagnetic lenses used in electron microscopy, most X-ray focusing optical systems have fixed optical parameters with constant numerical apertures (NAs). This lack of adaptability has significantly limited application targets. In the research described herein, we developed a variable-NA X-ray focusing system based on four deformable mirrors, two sets of Kirkpatrick–Baez-type focusing mirrors, in order to control the focusing size while keeping the position of the focus unchanged. We applied a mirror deformation procedure using optical/X-ray metrology for offline/online adjustments. We performed a focusing test at a SPring-8 beamline and confirmed that the beam size varied from 108 nm to 560 nm (165 nm to 1434 nm) in the horizontal (vertical) direction by controlling the NA while maintaining diffraction-limited conditions.

Ultraprecise piezoelectric deformable mirrors have been developed to construct adaptive X-ray focusing optics whose optical parameters can be varied while simultaneously performing wavefront correction. We designed and developed a deformable mirror that did not have high-spatial-frequency deformation errors. Using a Fizeau interferometer, we demonstrated that the mirror could be deformed with a peak-to-valley figure accuracy of 5 nm. In addition, wave-optical simulations based on the Fresnel–Kirchhoff integral revealed that the mirror could focus hard X-rays to 90 nm under diffraction-limited conditions.

Yoshio Ichii, Hiromi Okada, Hiroki Nakamori, Akihiko Ueda, Hiroyuki Yamaguchi, Satoshi Matsuyama, and Kazuto Yamauchi, "Development of a glue-free bimorph mirror for use in vacuum chambers", Review of Scientific Instruments 90, 021702 (2019), https://doi.org/10.1063/1.5066105., PZT (lead zirconate titanate)-glued bimorph deformable mirrors are widely used in hard X-ray regimes; however, they have not yet been used in soft X-ray regimes because they are less compatible for usage under high vacuum. In this study, we developed a glue-free bimorph deformable mirror, in which silver nano-particles were employed to bond PZT actuators to mirror substrates. Under an appropriate bonding condition, the bonding layer was confirmed to be uniform and the mirror's bending characteristics were demonstrated to be sufficiently stable; its gas emission rate was also shown to be acceptable. Piezo responses before and after additional heating at 200 °C showed the thermal stability of its bonding and bending properties.

We have developed the new hybrid adaptive X-ray mirror based on mechanical and piezo-driven deformation to realize precise shape controllability on a long-length mirror. The mechanical bender approximately provides the required ellipse, while the piezoelectric actuators attached to the mirror correct very small residual errors to satisfy the diffraction-limited condition. The mechanical bender significantly reduces the role of the piezoelectric actuator, resulting in the suppression of accuracy degradation due to the drift and/or junction effect of the piezoelectric actuators. In addition, line focusing was demonstrated with two different numerical apertures at SPring-8, and the obtained beam sizes were 127 and 253 nm (FWHM), which agree well with the diffraction-limited sizes.

Takumi Goto, Hiroki Nakamori, Takashi Kimura, Yasuhisa Sano, Yoshiki Kohmura, Kenji Tamasaku, Makina Yabashi, Tetsuya Ishikawa, Kazuto Yamauchi, and Satoshi Matsuyama, "Hard X-ray nanofocusing using adaptive focusing optics based on piezoelectric deformable mirrors", Review of Scientific Instruments 86, 043102 (2015) https://doi.org/10.1063/1.4916617., An adaptive Kirkpatrick-Baez mirror focusing optics based on piezoelectric deformable mirrors was constructed at SPring-8 and its focusing performance characteristics were demonstrated. By adjusting the voltages applied to the deformable mirrors, the shape errors (compared to a target elliptical shape) were finely corrected on the basis of the mirror shape determined using the pencil-beam method, which is a type of at-wavelength figure metrology in the X-ray region. The mirror shapes were controlled with a peak-to-valley height accuracy of 2.5 nm. A focused beam with an intensity profile having a full width at half maximum of 110 × 65 nm (V × H) was achieved at an X-ray energy of 10 keV.

Hard X-rays are high-energy photons with extremely short wavelengths of the order of atomic distances. Their short wavelengths allow hard X-rays to be focused to nanometer sizes. This concept is simple; however, it is technically difficult to implement. For this reason, many physicists have been investigating X-ray focusing. In this study, we produce a single-digit nanometer sized hard X-ray focal spot using an ultraprecise multilayer mirror. Such extremely narrow hard X-ray beams can be used to achieve extremely high spatial resolutions in various X-ray microscopy techniques. Coupled with the high pulse powers of X-ray free-electron lasers, such nanofocusing optics have the potential to exceed the Schwinger limit.

To construct an adaptive X-ray focusing optical system, we developed an ultraprecise deformable mirror that consists of a substrate, piezoelectric actuators, and 18 electrodes. A one-dimensional focusing test was performed at SPring-8 at 15 keV. The mirror deformation was roughly adjusted by applying voltages determined by a deformation test with a Fizeau interferometer. The shape was then finely corrected based on the shape determined by the pencil-beam method and the phase retrieval method. A focused beam with a full width at half maximum of 120 nm was obtained.

We have constructed an extremely precise optical system for hard-x-ray nanofocusing in a synchrotron radiation beamline. Precision multilayer mirrors were fabricated, tested, and employed as Kirkpatrick–Baez mirrors with a novel phase error compensator. In the phase compensator, an at-wavelength wavefront error sensing method based on x-ray interferometry and an in situ phase compensator mirror, which adaptively deforms with nanometer precision, were developed to satisfy the Rayleigh criterion to achieve diffraction-limited focusing in a single-nanometer range. The performance of the optics was tested at BL29XUL of SPring-8 and was confirmed to realize a spot size of approximately 7 nm.

High resolution imagery of the solar X-ray corona provides a crucial key to understand dynamics and heating processes of plasma particles there. However, X-ray imagery of the Sun with sub-arcsecond resolution has yet to be conducted due to severe technical difficulty in fabricating precision Wolter mirrors. For future X-ray observations of the Sun's corona, we are attempting to realize precision Wolter mirrors with sub-arcsecond resolution by adopting advanced surface polish and metrology methods based on nano-technology to sector mirrors which consist of a portion of an entire annulus. Following fabrication of the first engineering mirror and subsequent evaluation on the X-ray focusing performance in 2013, the second engineering mirror was made with improvements in both precision polish and metrology introduced. Measurement of focusing performance on the second mirror at SPring-8 synchrotron facility with 8 keV X-rays has demonstrated that the FWHM size of the PSF core reached down to 0.2" while its HPD (Half Power Diameter) size remained at ~3" due to the presence of small-angle scatter just outside of the core. Also, there was notable difference in the focal length between sagittal and meridional focusing which could have been caused by an error in the sag in the meridional direction of

A one-dimensional two-stage focusing system using two deformable mirrors was constructed. To realize the precise elliptical shapes, the mirror deformations were finely adjusted using the pencil-beam scan, which is a method of wavefront measurement. X-rays of 10 keV energy were one-dimensionally focused to a full width at half maximum of 90 nm, which agrees well with the diffraction limit.

Hiroki Nakamori, Satoshi Matsuyama, Shota Imai, Takashi Kimura, Yasuhisa Sano, Yoshiki Kohmura, Kenji Tamasaku, Makina Yabashi, Tetsuya Ishikawa, and Kazuto Yamauchi, "Experimental and simulation study of undesirable short-period deformation in piezoelectric deformable x-ray mirrors", Review of Scientific Instruments 83(5), 053701 (2012) https://doi.org/10.1063/1.4709499., To construct adaptive x-ray focusing optics whose optical parameters can be varied while performing wavefront correction, ultraprecise piezoelectric deformable mirrors have been developed. We computationally and experimentally investigated undesirable short-period deformation caused by piezoelectric actuators adhered to the substrate during mirror deformation. Based on the results of finite element method analysis, shape measurements, and the observation of x-ray reflection images, a guideline is developed for designing deformable mirrors that do not have short-period deformation errors. © 2012 American Institute of Physics.