We propose axial line-focused spiral zone plates （ALFSZPs） for generating tightly focused X-ray vortex beams with ultra-long depth of focus （DOF） along the propagation direction. In this typical design, compared w...We propose axial line-focused spiral zone plates （ALFSZPs） for generating tightly focused X-ray vortex beams with ultra-long depth of focus （DOF） along the propagation direction. In this typical design, compared with the conventional spiral zone plates （SZPs） under the same numerical aperture （NA）, the DOF of ALFSZPs has been extended to an ultra-length by optimizing the corresponding parameters. Besides, it also exhibits lower side lobes and smaller dark cores in the whole focus volume. The diameters of dark cores increase as the topological charge value increases.展开更多
The work proposes a three-laser-beam streak tube imaging lidar system. Besides the main measuring laser beam,the second beam is used to decrease the error of time synchronization. The third beam has n＋0.5 pixels＇ di...The work proposes a three-laser-beam streak tube imaging lidar system. Besides the main measuring laser beam,the second beam is used to decrease the error of time synchronization. The third beam has n＋0.5 pixels＇ difference compared to the main measuring beam on a CCD, and it is used to correct the error caused by CCD discrete sampling. A three-dimensional（3D） imaging experiment using this scheme is carried out with time bin size of 0.066 ns（i.e., corresponding to a distance of 9.9 mm）. An image of a 3D model is obtained with the depth resolution of 〈2 mm, which corresponds to ~0.2 pixel.展开更多
基金supported by the National Natural Science Foundation of China(Nos.11404290,61307019,11504333,and 61505178)the National Key Scientific Instruments and Equipments Development of Special Item,China(No.2012YQ130125)+1 种基金the Postdoctoral Science Foundation of Henan Province(No.2013008)the Program for Science&Technology Innovation Talents in Universities of Henan Province(No.172102210481)
文摘We propose axial line-focused spiral zone plates （ALFSZPs） for generating tightly focused X-ray vortex beams with ultra-long depth of focus （DOF） along the propagation direction. In this typical design, compared with the conventional spiral zone plates （SZPs） under the same numerical aperture （NA）, the DOF of ALFSZPs has been extended to an ultra-length by optimizing the corresponding parameters. Besides, it also exhibits lower side lobes and smaller dark cores in the whole focus volume. The diameters of dark cores increase as the topological charge value increases.
基金supported by the National Key Scientific Instrument and Equipment Development Projects of China(No.2012YQ040164)
文摘The work proposes a three-laser-beam streak tube imaging lidar system. Besides the main measuring laser beam,the second beam is used to decrease the error of time synchronization. The third beam has n＋0.5 pixels＇ difference compared to the main measuring beam on a CCD, and it is used to correct the error caused by CCD discrete sampling. A three-dimensional（3D） imaging experiment using this scheme is carried out with time bin size of 0.066 ns（i.e., corresponding to a distance of 9.9 mm）. An image of a 3D model is obtained with the depth resolution of 〈2 mm, which corresponds to ~0.2 pixel.
