The high flux of the white X-ray beams from third-generation synchrotron light sources can significantly benefit the development of high-speed X-ray imaging, but can also bring technical challenges to existing X-ray imaging systems. One prevalent problem is that the image quality deteriorates because of dust particles accumulating on the scintillator screen during exposure to intense X-ray radiation. Here, this problem has been solved by embedding the scintillator in a flowing inert-gas environment. It is also shown that the detector maintains the quality of the captured images even after days of X-ray exposure. This modification is cost-efficient and easy to implement. Representative examples of applications using the X-ray imaging system are also provided, including fast tomography and multimodal phase-contrast imaging for biomedical and geological samples.

The recently developed speckle-based technique is a promising candidate for laboratory-based X-ray phase-contrast imaging due to its compatibility with polychromatic X-rays, multi-modality and flexibility. Previously, successful implementations of the method on laboratory systems have been shown mostly with energies less than 20 keV on samples with materials like soft tissues or polymer. Higher energy X-rays are needed for penetrating materials with a higher atomic number or that are thicker in size. A first demonstration using high energy X-rays was recently given. Here, we present more potential application examples, i.e., a multi-contrast imaging of an IC chip and a phase tomography of a mortar sample, at an average photon energy of 40 keV using a laboratory X-ray tube. We believe the results demonstrate the applicability of this technique in a wide range of fields for non-destructive examination in industry and material science.

X-ray mirrors are widely used in beamlines and laboratories as focusing or collimating optics. As well as the highly accurate processes used to fabricate them, optimized alignment of X-ray mirrors also plays an important role in achieving an ideal X-ray beam. Currently, knife-edge scans are the most often used method for aligning X-ray mirrors, which can characterize the focal size and tune the alignment iteratively. However, knife-edge scanning provides only one-dimensional information and this method suffers from being time-consuming and requiring a high-resolution piezo translation stage. Here we describe a straightforward and non-iterative method for mirror alignment by measuring the relationship between the tilt aberration and the misaligned pitch angle, which is retrieved by an at-wavelength metrology technique using a randomly shaped wavefront modulator. Software and a graphical user interface have been developed to automate the alignment process. Combining the user-friendly interface and the flexibility of the at-wavelength metrology technique, we believe the proposed method and software can benefit researchers working at synchrotron facilities and on laboratory sources.

X-ray phase-contrast imaging can substantially enhance image contrast for weakly absorbing samples. The fabrication of dedicated optics remains a major barrier, especially in high-energy regions (i.e. over 50 keV). Here, the authors perform X-ray phase-contrast imaging by using engineered porous materials as random absorption masks, which provides an alternative solution to extend X-ray phase-contrast imaging into previously challenging higher energy regions. The authors have measured various samples to demonstrate the feasibility of the proposed engineering materials. This technique could potentially be useful for studying samples across a wide range of applications and disciplines.

At-wavelength metrology of X-ray optics plays a crucial role in evaluating the performance of optics under actual beamline operating conditions, enabling in situ diagnostics and optimization. Techniques utilizing a wavefront random modulator have gained increasing attention in recent years. However, accurately mapping the measured wavefront slope to a curved X-ray mirror surface when the modulator is downstream of the mirror has posed a challenge. To address this problem, an iterative method has been developed in this study. The results demonstrate a significant improvement compared with conventional approaches and agree with offline measurements obtained from optical metrology. We believe that the proposed method enhances the accuracy of at-wavelength metrology techniques, and empowers them to play a greater role in beamline operation and optics fabrication.

Bumblebees are important pollinators, that are declining rapidly in number and need urgent protection. Visual cues are extremely important for bumblebee activities and survival so a full understanding of the micro-and nano-structure of their eyes will help us to better understand their vision and how it is affected by rapid habitat changes. Here, we present the first report on imaging of 3D structures with sub-100 nm resolution of an unstained bumblebee compound eye using X-ray holographic tomography. This study demonstrates the potential of using X-ray nano-tomography for bulk samples for zoological studies on insects. Compared to the other commonly used methods, such as TEM and FIB-SEM, X-ray nanoCT is non-destructive and relatively fast, and has the potential for providing a better understanding of a broad range of biological materials.