The 9th International Conference on Matter and Radiation at Extremes (ICMRE2026) ( ICMRE2026)

X-ray curved crystal systems have become an essential tool for laser plasma diagnostics due to their excellent spectral resolution, high collection efficiency, and high spatial resolution. However, the transient processes of plasma impose stringent requirements on focusing flux and spatial resolution, causing traditional spherical bent crystal configurations with a single parameter to be severely limited. This report introduces several types of focusing imaging X-ray curved crystal devices developed by our research group based on sagittal surface shape regulation, mainly including: (1) To eliminate the constraints on spatial resolution caused by the astigmatism of traditional spherical bent crystals, a toroidal configuration with independently controlled meridional and sagittal radii of curvature was adopted to effectively eliminate astigmatism; meanwhile, an offline alignment method based on energy substitution was developed to achieve precise characterization of the object-image relationship for toroidal imaging crystals^[1]. (2) To support the experimental application of toroidal crystals coupled with multichannel configurations, an offline precision alignment technology based on the visible light Talbot effect was proposed to accurately indicate the precise object-image relationship of multichannel curved crystals^[2]. (3) To meet the high-precision diagnostic needs for time-varying spectra, a multichannel framed FSSR spectrometer structure was developed by combining precise regulation of crystal surface shape with multichannel configuration design^[3]. This effectively enhances the focusing flux of the device while maintaining high spectral resolution. Combined with the optimized selection of crystal materials and orientations, the spectral range of the curved crystal spectrometer was effectively broadened, achieving multi-frame and broadband detection of plasma X-ray radiation.