Development of a four-color quasimonochromatic X-ray microscope for laser plasma research

X-ray multicolor imaging diagnosis obtains the spatial distribution of the imploding core during laser inertial confinement fusion. We propose a four-color quasimonochromatic X-ray microscope based on the Kirkpatrick-Baez microscope configuration, covering the medium-to-high-energy X-ray range. Composed of single-layer film mirrors and periodic multilayer film mirrors, the microscope features high spatial resolution and spectral resolution. Furthermore, zoned coating technology achieves common field-of-view (FOV) imaging at four energy points: 4.51, 6.4, 8.4, and 9.67 keV. When assembled and calibrated in the laboratory, the microscope achieved central FOV spatial resolutions of 3.9, 3.7, 4.0, and 4.1 µm at 4.51, 6.4, 8.04, and 9.67 keV, respectively. Finally, a spectral calibration experiment confirmed spectral selectivity at the four energy points.