A novel method for automatic ultra-precision alignment is presented.This method relies on the modified Moiré technique,and alignment marks are used in the form of gratings.The modified Moiré technique can ef...A novel method for automatic ultra-precision alignment is presented.This method relies on the modified Moiré technique,and alignment marks are used in the form of gratings.The modified Moiré technique can effectively improve detecting sensitivity of signals and simplify the control system by using only one pair of laser-Moiré sensors.We present the mathematical model and simulation results of diffracting two gratings.The effect of various parameters on Moiré signals is studied theoretically and experimentally,and the results are found to be consistent.A computer controlled alignment device using one pair of Moiré sensors is designed.The device can achieve a fully automatic precision alignment by the modified Moiré signal.The experimental result shows that the alignment device can obtain the resolution of 5 nm and the positioning accuracy of ±0 5 μm.展开更多
Based on the moiré effect and the Fresnel diffraction theory, a novel technique for diagnosing the beam properties is presented and analyzed, which is especially suitable for X-ray lasers. The method makes it pos...Based on the moiré effect and the Fresnel diffraction theory, a novel technique for diagnosing the beam properties is presented and analyzed, which is especially suitable for X-ray lasers. The method makes it possible, in a one-shot experimental measurement, to determine the beam quality factor M2, the effective radius of curvature, the beam width, the far-field divergence, and the waist location and radius as well as the spatial coherence and its evolution. Numerical simulation proves the validity of the method. Note that the novel moiré technique opens an efficient road, for the first time, to fully diagnose the spatial properties of X-ray lasers.展开更多
文摘A novel method for automatic ultra-precision alignment is presented.This method relies on the modified Moiré technique,and alignment marks are used in the form of gratings.The modified Moiré technique can effectively improve detecting sensitivity of signals and simplify the control system by using only one pair of laser-Moiré sensors.We present the mathematical model and simulation results of diffracting two gratings.The effect of various parameters on Moiré signals is studied theoretically and experimentally,and the results are found to be consistent.A computer controlled alignment device using one pair of Moiré sensors is designed.The device can achieve a fully automatic precision alignment by the modified Moiré signal.The experimental result shows that the alignment device can obtain the resolution of 5 nm and the positioning accuracy of ±0 5 μm.
基金supported by the National High Technology Research and Development Program of China.
文摘Based on the moiré effect and the Fresnel diffraction theory, a novel technique for diagnosing the beam properties is presented and analyzed, which is especially suitable for X-ray lasers. The method makes it possible, in a one-shot experimental measurement, to determine the beam quality factor M2, the effective radius of curvature, the beam width, the far-field divergence, and the waist location and radius as well as the spatial coherence and its evolution. Numerical simulation proves the validity of the method. Note that the novel moiré technique opens an efficient road, for the first time, to fully diagnose the spatial properties of X-ray lasers.
