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In this work, a masking technique was used to improve the thickness uniformity of a Mo/Si multilayer deposited on a curved spherical mirror by direct current (DC) magnetron sputtering with planetary rotation stages. The clear aperture of the mirror was 125 mm with a radius of curvature equal to 143.82 mm. Two different shadow masks were prepared, one was flat and the other was oblique. When using the flat mask, the non-uniformity considerably increased owing to the relatively large gap between the mask and substrate. The deviation between the designed and measured layer thickness and non-uniformity gradually reduced with a smaller gap. The second mask was designed with an oblique profile. Using the oblique mask, the deviation from multilayer thickness uniformity was substantially reduced to a magnitude below 0.8% on the curved spherical substrate over the clear aperture of 125 mm. Multilayers still achieved a smooth growth when deposited with obliquely incident particles. The facile masking technique proposed in this study can be used for depositing uniform coatings on curved spherical substrates with large numerical apertures for high-resolution microscopes, telescopes, and other related optical systems.

A time-resolved multispectral X-ray imaging approach with new version of multi-channel Kirkpatrick-Baez (KB) microscope is developed for laser plasma diagnostics at the kilojoule-class Shenguang-II laser facility (SG-II). The microscope uses a total external reflection mirror in the sagittal direction and an array of multilayer mirrors in the tangential direction to obtain multiple individual high-resolution, highthroughput, and quasi-monochromatic X-ray images. The time evolution of the imploded target in multiple X-ray energy bands can be acquired when coupled with an X-ray streak camera. The experimental result of the time-resolved 2.5 and 3.0 keV dual-spectral self-emission imaging of the undoped CH shell target on SG-II is given.

A four-channel multilayer Kirkpatrick-Baez (KB) microscope is developed for the 8-keV X-ray imaging of experiments on laser inertial confinement fusion (ICF). A periodic multilayer that works at 8 keV and with a grazing incidence angle of 1.0o is coated on reflective surfaces to achieve a spatial resolution higher than 5 \mu m and an effective solid angle higher than ~10-7 sr. A precise assembly is realized by a conical reference cone to couple with an X-ray framing camera. This study provides detailed information on an optical and multilayer design, assembly method, and experimental results with a Cu X-ray tube. The instrument provides a high-resolution and high-throughput X-ray image for backlit or self-emission imaging of laser plasma at Cu K\alpha line radiation in Shenguang series laser facilities.

A four-channel Kirkpatrick-Baez microscope working at multiple energy bands is developed for multiframe X-ray imaging diagnostics at the Shenguang-II laser facility. The response to the multiple energy bands is realized by coating the double-periodic multilayers on the reflected surfaces of the microscope. Because of the limited size of the microstrips in the X-ray framing camera, the image separation is controlled by the conical angle of the reference cores during microscope assembly. This study describes the optical and multilayer design, assembly, and alignment of the developed microscope. The microscope achieves a spatial resolution of 4-5 mm in the laboratory and 10-20 mm at Shenguang-II laser facility within a 300 mm field of view. The versatile nature of the developed microscope enables the multiple microscopes currently installed in the laser facility to be replaced with a single, multipurpose microscope.

The imaging characteristic of non-periodic multilayer Kirkpatrick-Baez(KB) microscope is analyzed based on propagation of rays, and contrasted with single layer and periodic multilayer KB microscopes. Compared with single layer KB microscope, multilayer KB microscope has bigger grazing angle, and wider field of view at the same resolution and collection efficiency. The reflectivity and energy resolution of periodic multilayer KB microscope is better than that of non-periodic multilayer KB microscope, but the non-periodic multilayer element has wider angular bandwidth and more uniform reflectivity, which improves the field of view and uniformity of image. The non-periodic multilayer mirrors with a grazing angle of 1.133 0° possess 0.3° angular bandwidth. Backlit by 8 keV X-ray tube, the i

The coupling efficiency of short-pulse ignition laser energy to hot-spot internal energy directly affects the feasibility of fast ignition. Experimental characterization of the hot spot has attracted much attention. Among temperature, density and neutron yield of fast ignition experiments, the temperature of the hot spot has few available diagnostic methods. Multispectral X-ray imaging of hot-spot continuum emission is expected to give the time evolution of the electron temperature distribution. This article describes electron temperature determination from multispectral imaging, a dual-channel X-ray Kirkpatrick-Baez (KB) microscope designed for two-spectral imaging, and the experimental results of hot-core multispectral imaging of an imploded cone-shell target at the SG-II laser facility.

The X-ray Kirkpatrick-Baez (KB) imaging experiment with single layer is implemented. Based on the astigmatism aberration and residual geometric aberration of a single mirror, a KB system with 16X mean magnification and approximately 0.45\circ razing incidence angle is designed. The mirrors are deposited with an Ir layer of 20-nm thickness. Au grids backlit by X-ray tube of 8 keV are imaged via the KB system on scintillator charge-coupled device (CCD). In the \pm80 \mum field, resolutions of less than 5 \mum are measured. The result is in good agreement with the simulated imaging.