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Plasma Science and Technology 2012年第1期14卷 20-23页

作者： ZHOU Mulin LIU Feng LI Chun DU Fei LI Yutong WANG Weimin SHENG Zhengning CHEN Liming MA Jingong LU Xin DONG Quanli ZHANG Jie Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Key Laboratory for Laser Plasmas(Ministry of Education)and Department of Physics Shanghai Jiao Tong UniversityShanghai 200240China

A new method based on a chirped optical pulse interferogram has been proposed to measure terahertz radiation. The frequency domain phase information of the interferogram is used to extract the time-domain terahertz pulse waveform. In principle, the resolution of our method can be as high as the unchirped probe pulse duration, with the advantages of relatively simple measurement setup and signal extracting techniques.

关键词： single shot measurement interferogram phase modulation

THE OPTICAL PROPERTIES OF THE LASER BEAM PASSED THROUGH A TURBULENT SHEAR LAYER

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Acta Mechanica Sinica 1987年第3期3卷 214-222页

作者： Chen Haitao (Institute of Mechanics,Academia Sinica) Institute of Mechanics Academia Sinica Taiwan

The related fluid dynamic theory,experimental device and some preliminary results of thestudy of the optical properties of a laser beam passed through a turbulent shear layer are *** of image processing for the determination of the optical density from a intederogram by means of aMicroneye Bullet and a Microcomputer is also described.

关键词： optical property laser beam quality turbulent shear layer interferogram image processing

Vortex Field Propagation in a Hexagonal Multicore Fiber Array

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Optics and Photonics Journal 2014年第1期4卷 1-7页

作者： Muhammad A. Mushref Department of Electrical Engineering and Computer Science University of Wisconsin-Milwaukee Milwaukee USA

The propagation of an optical vortex in a hexagonally arranged single mode multicore fiber structure is investigated for possible generation of additional vortices and their spread dynamics. Fields are separated into a slowly varying paraxial envelope and a rapidly changing exponential component. Solutions are derived from the paraxial inhomogeneous Schrodinger equation in two dimensions along with the index of refraction of the proposed structure. Numerical analyses are based on the beam propagation method and transparent boundary conditions in matrix form with different parameters to represent the intensity and phase of all derived fields. Vortices are numerically identified by their points of zero intensity and their phase change or polarity. The optical interferogram with a plane wave reference is also employed to distinguish the dislocation points in the transverse directions of the propagating fields.

关键词： Optical Vortex Beam Propagation Method Transparent Boundary Conditions Multicore Fibers Optical interferogram

A NEW ALGORITHM FOR SCANSAR PROCESSING

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Journal of Electronics(China) 2001年第3期18卷 228-236页

作者： Qiao Rongrong Wang Zhensong Ian Gumming(institute of Electronics, Chinese Academy of Sciences, Beijing 100080) Institute of Electronics Chinese Academy of Sciences Beijing 100080

In this paper, a new phase preserving algorithm-the short IFFT algorithm for the burst-mode ScanSAR processing is presented. Analysis and simulation are done to verify the phase accuracy of this algorithm. Finally, the phase accuracy of this algorithm by making interferogram with simulated burst-mode INSAR data is illustrated. The results show that this new algorithm works well for interferometric application of ScanSAR data.

关键词： ScanSAR SIFFT algorithm IFFT interferogram

Thermal Stress Monitoring on Piston Rings by Real Time Holographic Interferometry

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Optics and Photonics Journal 2013年第8期3卷 379-384页

作者： Stephen N. Maina Geoffrey K. Rurimo Patrick M. Karimi Dickson M. Kinyua Calvin F. Ominde Department of Physics Jomo Kenyatta University of Agriculture & Technology Nairobi Kenya Department of Physics Kenyatta University Nairobi Kenya

In this paper, real time holographic Interferometry (RTHI) technique was used to monitor the thermal stress on the piston rings. The piston rings holograms were recorded and the holographic plate replaced on the holder after development. The piston ring was subjected to thermal stress as it was illuminated by Laser beam acting as the object beam. This process led to generation of interferograms which were captured by a CCD camera at different temperatures. The captured interferograms were analyzed using atmosfringe version 3.3 software. From the analysis, the peak to valley (P-V) aberrations measured for each of the piston ring varied for the same temperature value. The P-V aberrations ranging from 0.0128λ to 1.2989λ were obtained. From this result, it was evident that the three rings on the piston had different unique structural characteristics due to their function.

关键词： interferogram Hologram Aberration Piston Ring Laser Beam

InSAR Observation for the Surface Displacements at Mt. Etna between 2003 and 2007

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International Journal of Geosciences 2015年第2期6卷 159-171页

作者： Syeda Sabikun Nahar Arif Mahmud BGMEA University of Fashion and Technology Dhaka Bangladesh

This research is mainly devoted to InSAR observations using Poly-interferogram Rate and Time-series Estimator (π-rate) software to investigate continuous surface displacement at Mt. Etna (Sicily), Italy between 2003 and 2007. Using ascending and descending SAR images produced by European Space Agency’s ENVISAT, we generate a set of interferograms which are used to determine?the deformation history of Etna from 2003 to 2007. Using (π-rate), we can generate the InSAR?time-series and ratemap while minimizing errors induced by the satellites orbit and atmospheric?phase delays. During the period of 2003-2007, three separate eruptions were observed. In order to explain the deformation, we solve three displacement rate for 2003-2005, 2006 and 2007. As expected, the result suggests that displacement rates are not constant with respect to time. During 2006 the volcano appeared to switch from a period of deflation to a period of inflation. These results highlight the importance of InSAR for generating deformation time-series around Mt.?Etna, and with the application of numerical models these results can be used to estimate the?amount of magma moving in the subsurface.

关键词： InSAR interferogram Ratemap Eruptions Magma and π-Rate

Research on Characteristics of Focal Rupture of the Zhangbei-Shangyi Earthquake by Means of Deformation Field Obtained by Spaceborne D-INSAR

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Earthquake Research in China 2003年第2期17卷 113-121页

作者： ShanXinjian MaJin SongXiaoyu WangChao LiuJiahang ZhangGuifang InstituteofGeology ChinaSeismologicalBureau LaboratorvofTectonophvsiesCSB Beijing100029China InstituteofRemoteSensingApplications ChineseAcademyofSciencesBeijing100029.China

In the last ten years, the D_InSAR (Differential Interferometric Synthetic Aperture Radar) technique has proved very useful; it has been a new space observation technique with great potential. Investigating seismic focus rupture information using D_InSAR is a scientific issue to which more attention is being paid. In this paper, the basic theory of seismic focus dislocation models is discussed briefly. Based on a map of the interferometric deformation field of the Zhangbei_Shangyi earthquake from Jan.10, 1998, and applying the seismic focus dislocation model within elastic half_space medium; some geometrical and kinematical characteristics of the main seismic fault are deduced. Results were as follows: the seismic break surface of the Zhangbei_Shangyi earthquake is left_slip and thrust fault, striking in SEE_NWW 272°with dip angle 46°; rupture direction is unilateral faulting from SEE to NWW; length of rupture zone is 9km, width is 8km, and depth is 8km, the displacement vector of three directions are 290mm, 560mm and 0mm.

关键词： D-InSAR interferogram Focal dislocation Focal characteristics Zhangbei-Shangyi earthquake

Spatial Light Modulator with BSO Crystal and Its Application in Holography

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Semiconductor Photonics and Technology 1998年第1期4卷 36-39页

作者： WANG Wensheng (Changchun College of Optics and Fine Mechanics,Changchun 130022,CHN)

The combined use of the photoelectric and electro-optic properties of BSO crystal (Bi 12 SiO 20 ) leads to realize spatial light *** some condition,BSO crystal can become birefringent depending on a local *** relationship between the distributions of an illuminance and a birefringence will be *** spatial light modulator can work in real-time. The experiment shows,in order to increase the sensitivity of BSO crystal,an electric field of 6 kV/cm at an atmosphere pressure of 15×10 5 Pa should be applied to BSO *** BSO we have measured 3-dimensional deformation by means of real-time holography.

关键词： BSO Crystal Computer Holography interferogram Spatial Light Modulator TV-monitor

Observation of the Metallic Vaporfrom a Plasma Focus

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Tsinghua Science and Technology 1999年第4期4卷 1695-1697页

作者：王新新杨津基 Department of Electrical Engineering Tsinghua University Beijing 100084

Although many scientists suggested that the ionized metallic vapor produced in plasma focus plays asignificantrole in the X ray emission,they did not give a visualimage ofthe metallic *** this paper the evolution of plasma sheath above the anode was recorded with a laser differentialinterferometer and the metallic vapor produced onthetargetsurface by bombardmentofanintense electron beam was observedforthe firsttime. The results can help understanding ofthe physicalprocess ofthe X ray emissionfrom plasma focus.

关键词： plasmafocus X ray emission interferogram