By using an amplitude-type spatial light modulator to load angular spectrum of Mathieu function distribution along a narrow annular pupils, the Durnin’s experimental setup is extended to generate various types of Mat...By using an amplitude-type spatial light modulator to load angular spectrum of Mathieu function distribution along a narrow annular pupils, the Durnin’s experimental setup is extended to generate various types of Mathieu beams. As a special type of Mathieu beams, Bessel beams are also generated using this optical setup. Furthermore, the optical morphology of the Mathieu beams family are also presented and analyzed.展开更多
Based on the angular spectrum method and the circular Gaussian distribution(CGD) model of scattering media,we numerically simulate light focusing through strongly scattering media.A high contrast focus in the target a...Based on the angular spectrum method and the circular Gaussian distribution(CGD) model of scattering media,we numerically simulate light focusing through strongly scattering media.A high contrast focus in the target area is produced by using feedback optimization algorithm with binary amplitude modulation.It is possible to form the focusing with one focus or multiple foci at arbitrary areas.The influence of the number of square segments of spatial light modulation on the enhancement factor of intensity is discussed.Simulation results are found to be in good agreement with theoretical analysis for light refocusing.展开更多
A method for beam diffraction sidelobe suppression based on the combination of volume Bragg gratings（VBGs）with different thicknesses or periods for angular filtering is proposed and performed. Simulated and experime...A method for beam diffraction sidelobe suppression based on the combination of volume Bragg gratings（VBGs）with different thicknesses or periods for angular filtering is proposed and performed. Simulated and experimental results show that the beam diffraction sidelobe is reduced from 12% to less than 1% with the non-sidelobe angular filter. The non-sidelobe angular filtering based on VBGs with thicknesses of 2.5 and 2.9 mm is simulated and demonstrated. The near-field distribution of filtered beams through the non-sidelobe angular filter is obviously smoother than that of the single VBG. The near-field modulation and contrast ratio（C） of filtered beams are found to be improved 1.17 and 1.66 times that of the single VBG. The far-field C of the filtered beam is improved to about 100∶1 and the power spectral density analysis shows that the cutoff frequency of the angular filter is greatly optimized with the VBG combination.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11674288)
文摘By using an amplitude-type spatial light modulator to load angular spectrum of Mathieu function distribution along a narrow annular pupils, the Durnin’s experimental setup is extended to generate various types of Mathieu beams. As a special type of Mathieu beams, Bessel beams are also generated using this optical setup. Furthermore, the optical morphology of the Mathieu beams family are also presented and analyzed.
基金supported by the National Natural Science Foundation of China(Nos.61178015 and 11304104)
文摘Based on the angular spectrum method and the circular Gaussian distribution(CGD) model of scattering media,we numerically simulate light focusing through strongly scattering media.A high contrast focus in the target area is produced by using feedback optimization algorithm with binary amplitude modulation.It is possible to form the focusing with one focus or multiple foci at arbitrary areas.The influence of the number of square segments of spatial light modulation on the enhancement factor of intensity is discussed.Simulation results are found to be in good agreement with theoretical analysis for light refocusing.
基金supported by the National Natural Science Foundation of China(Nos.61275140,61370182,and11504255)the Natural Science Foundation of JiangsuProvince(No.DK20141232)+1 种基金a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the National“863”Program of China
文摘A method for beam diffraction sidelobe suppression based on the combination of volume Bragg gratings（VBGs）with different thicknesses or periods for angular filtering is proposed and performed. Simulated and experimental results show that the beam diffraction sidelobe is reduced from 12% to less than 1% with the non-sidelobe angular filter. The non-sidelobe angular filtering based on VBGs with thicknesses of 2.5 and 2.9 mm is simulated and demonstrated. The near-field distribution of filtered beams through the non-sidelobe angular filter is obviously smoother than that of the single VBG. The near-field modulation and contrast ratio（C） of filtered beams are found to be improved 1.17 and 1.66 times that of the single VBG. The far-field C of the filtered beam is improved to about 100∶1 and the power spectral density analysis shows that the cutoff frequency of the angular filter is greatly optimized with the VBG combination.
