Optical orbital angular momentum(OAM)multiplexed holography has been implemented as an effective method for information encryption and storage.Multiramp helicoconical-OAM multiplexed holography is proposed and experim...Optical orbital angular momentum(OAM)multiplexed holography has been implemented as an effective method for information encryption and storage.Multiramp helicoconical-OAM multiplexed holography is proposed and experimentally implemented.The mode selectivity of the multiramp mixed screw-edge dislocations,constant parameter K,and normalized factor are investigated,respectively,which demonstrates that those parameters can be used as additional coding degrees of freedom for holographic multiplexing.The combination of the topological charge and the other three parameters can provide a four-dimensional multiplexed holography and can enhance information capacity.展开更多
The two-dimensional angular filter based on volume Bragg gratings in photothermorefractive glass for a nanosecond(ns) laser pulse is demonstrated. The experimental results show that the near-field beam quality of the...The two-dimensional angular filter based on volume Bragg gratings in photothermorefractive glass for a nanosecond(ns) laser pulse is demonstrated. The experimental results show that the near-field beam quality of the laser pulse was effectively improved. The near-field modulation and contrast ratio were improved by 1.75 and4.48 times, respectively. The power spectral density curves showed that the spatial frequencies more than0.9 mm^(-1)in the x direction and 1.2 mm^(-1)in the y direction were effectively suppressed.展开更多
FM-to-AM conversion for angular filtering based on transmitted volume Bragg gratings(TBGs)is discussed.Simulation results show that a narrower spectral selectivity of TBGs led to stronger FM-to-AM conversion.Good angu...FM-to-AM conversion for angular filtering based on transmitted volume Bragg gratings(TBGs)is discussed.Simulation results show that a narrower spectral selectivity of TBGs led to stronger FM-to-AM conversion.Good angular selectivity and a wide bandwidth for the TBGs can be obtained by controlling the grating period and thickness.FM-to-AM conversion can be effectively suppressed and the distortion criterion for the filtered beam reduces to less than 5%.FMto-AM conversion of TBGs is demonstrated in the’Shenguang’ facility,and the results are in good agreement with the simulation.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.61775153)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Optical orbital angular momentum(OAM)multiplexed holography has been implemented as an effective method for information encryption and storage.Multiramp helicoconical-OAM multiplexed holography is proposed and experimentally implemented.The mode selectivity of the multiramp mixed screw-edge dislocations,constant parameter K,and normalized factor are investigated,respectively,which demonstrates that those parameters can be used as additional coding degrees of freedom for holographic multiplexing.The combination of the topological charge and the other three parameters can provide a four-dimensional multiplexed holography and can enhance information capacity.
基金supported by the National Key R&D Program of China(No.2016YFF0100900)the National Natural Science Foundation of China(NSFC)(Nos.61775153,61705153,and 11504255)+1 种基金the Natural Science Foundation of Jiangsu Province(No.BK20141232)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘The two-dimensional angular filter based on volume Bragg gratings in photothermorefractive glass for a nanosecond(ns) laser pulse is demonstrated. The experimental results show that the near-field beam quality of the laser pulse was effectively improved. The near-field modulation and contrast ratio were improved by 1.75 and4.48 times, respectively. The power spectral density curves showed that the spatial frequencies more than0.9 mm^(-1)in the x direction and 1.2 mm^(-1)in the y direction were effectively suppressed.
基金supported by the National Key R&D Program of China(No.2016YFF0100903)National Natural Science Foundation of China(NSFC)(Nos.61775153,61705153,and 11504255)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘FM-to-AM conversion for angular filtering based on transmitted volume Bragg gratings(TBGs)is discussed.Simulation results show that a narrower spectral selectivity of TBGs led to stronger FM-to-AM conversion.Good angular selectivity and a wide bandwidth for the TBGs can be obtained by controlling the grating period and thickness.FM-to-AM conversion can be effectively suppressed and the distortion criterion for the filtered beam reduces to less than 5%.FMto-AM conversion of TBGs is demonstrated in the’Shenguang’ facility,and the results are in good agreement with the simulation.
