In the spectrum diagnostic physics experiment of inertial confinement fusion, the spectral signal is weak due to the X-ray diffraction efficiency with crystal. So a spectral diagnostic instrument with high light collection efficiency and wide spectral range is urgently needed. A multi-curvature bent crystal multi-energy point imaging technique is proposed based on traditional conical crystal structure. It has the characteristics of wide spectral range, strong focusing ability and high spectral resolution. At the same time, it can eliminate imaging aberration in principle due to the rotational symmetry of imaging light. The measuring spectra experiment of multi-curvature bent α-quartz crystal is conducted at a Ti X-ray tube device and the same experiment with plane α-quartz crystal is done to demonstrate the strong focusing ability. The result shows that the intensity of multi-curvature bent α-quartz crystal is 100 times than that of plane crystal, and the energy range of detected X-ray is 4.51~5.14 keV. This device combined with a streak camera at a vertical direction could be used to collect weak X-ray with wide spectral range.