New Streak Tube Without Time-Dispersion Slit Image Curvature

1983 ◽  
Author(s):  
Katsuyuki Kinoshita ◽  
Nobuyuki Hirai ◽  
Yutaka Tsuchiya
Keyword(s):  
Time Dispersion ◽  
Image Curvature ◽  
Streak Tube

Picosecond and femtosecond streak cameras: present and future designs

1980 ◽  
Vol 298 (1439) ◽  
pp. 281-285 ◽  
Keyword(s):  
Time Resolution ◽  
Time Domain ◽  
Optical Design ◽  
Preliminary Design ◽  
X Ray ◽  
Time Dispersion ◽  
Expected Performance ◽  
Experimental Values ◽  
Imaging Properties ◽  
Streak Tube

For many applications of time-domain spectroscopy it is desirable to improve the time resolution of electron-optical streak cameras to less than 200 fs in the u.v. visible and i.r. and to ca . 1 ps at X-ray wavelengths. A suite of interactive computer programs has been developed for electron-optical design, taking into account time dispersion. It is possible to analyse rapidly the details of both spatial and temporal imaging properties of currently available streak tubes and to optimize the designs for particular applications. The computed results are shown to be in excellent agreement with the experimental values for the Photochron II streak tube. The expected performance characteristics of a preliminary design for a new tube, the Photochron III, are given.

Optical data signals in fiber optic communication links with fading

2019 ◽  
pp. 94-104
Author(s):  
I. Juwiler ◽  
I. Bronfman ◽  
N. Blaunstein
Keyword(s):  
Spectral Efficiency ◽  
Fiber Optic ◽  
Fiber Optic Cable ◽  
Optical Signals ◽  
Dispersion Properties ◽  
Optical Cable ◽  
Time Dispersion ◽  
Communication Links ◽  
Fiber Optic Communication ◽  
Optic Communication

Introduction: This article is based on the recent research work in the field of two subjects: signal data parameters in fiber optic communication links, and dispersive properties of optical signals caused by non-homogeneous material phenomena and multimode propagation of optical signals in such kinds of wired links.Purpose: Studying multimode dispersion by analyzing the propagation of guiding optical waves along a fiber optic cable with various refractive index profiles of the inner optical cable (core) relative to the outer cladding, as well as dispersion properties of a fiber optic cable due to inhomogeneous nature of the cladding along the cable, for two types of signal code sequences transmitted via the cable: return-to-zero and non-return-to-zero ones.Methods: Dispersion properties of multimode propagation inside a fiber optic cable are analyzed with an advanced 3D model of optical wave propagation in a given guiding structure. The effects of multimodal dispersion and material dispersion causing the optical signal delay spread along the cable were investigated analytically and numerically.Results: Time dispersion properties were obtained and graphically illustrated for two kinds of fiber optic structures with different refractive index profiles. The dispersion was caused by multimode (e.g. multi-ray) propagation and by the inhomogeneous nature of the material along the cable. Their effect on the capacity and spectral efficiency of a data signal stream passing through such a guiding optical structure is illustrated for arbitrary refractive indices of the inner (core) and outer (cladding) elements of the optical cable. A new methodology is introduced for finding and evaluating the effects of time dispersion of optical signals propagating in fiber optic structures of various kinds. An algorithm is proposed for estimating the spectral efficiency loss measured in bits per second per Hertz per each kilometer along the cable, for arbitrary presentation of the code signals in the data stream, non-return-to zero or return-to-zero ones. All practical tests are illustrated by MATLAB utility.

Research on a flash imaging lidar based on a multiple-streak tube

Laser Physics ◽  
2009 ◽  
Vol 19 (1) ◽  
pp. 115-120 ◽  
Author(s):  
J. Liu ◽  
Q. Wang ◽  
S. Li ◽  
Y. Cheng ◽  
J. Wei
Keyword(s):  
Streak Tube

scholarly journals Space-time dispersion of graphene conductivity

2007 ◽  
Vol 56 (4) ◽  
pp. 281-284 ◽  
Author(s):  
L. A. Falkovsky ◽  
A. A. Varlamov
Keyword(s):  
Space Time ◽  
Time Dispersion

Large photocathode area picosecond streak tube

2008 ◽  
Author(s):  
S. V. Andreev ◽  
V. S. Belolipetski ◽  
S. R. Ivanova ◽  
T. P. Kulechenkova ◽  
G. P. Levina ◽  
...  
Keyword(s):  
Streak Tube

Improvement of image quality of framing streak tube with FOP output window

1993 ◽  
Author(s):  
Kuniyoshi Mori ◽  
Kenji Suzuki ◽  
Koichiro Oba
Keyword(s):  
Image Quality ◽  
Output Window ◽  
Streak Tube

Small-size streak tube with high edge spatial resolution

Optik ◽  
2021 ◽  
pp. 166791
Author(s):  
Liping Tian ◽  
Lingbin Shen ◽  
Lili Li ◽  
Xing Wang ◽  
Ping Chen ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Streak Tube

Time dispersion correction for arbitrarily even-order Lax-Wendroff methods and the application on full waveform inversion

Geophysics ◽  
2021 ◽  
pp. 1-89
Author(s):  
Zhiming Ren ◽  
Qianzong Bao ◽  
Bingluo Gu
Keyword(s):  
Waveform Inversion ◽  
Second Order ◽  
High Order ◽  
Full Waveform Inversion ◽  
Dispersion Correction ◽  
Equal Time ◽  
Full Waveform ◽  
Time Dispersion ◽  
Correction Scheme ◽  
Even Order

A second-order accurate finite-difference (FD) approximation is commonly used to approximate the second-order time derivative of wave equation. The second-order accurate FD scheme may introduce time dispersion in wavefield extrapolation. Lax-Wendroff methods can suppress such dispersion by replacing the high-order time FD error-terms with space FD error correcting terms. However, the time dispersion cannot be completely eliminated and the computation cost dramatically increases with increasing order of (temporal) accuracy. To mitigate the problem, we extend the existing time dispersion correction scheme for second- or fourth-order Lax-Wendroff method to a scheme for arbitrary even-order methods, which uses the forward and inverse time dispersion transform (FTDT and ITDT) to add and remove the time dispersion from synthetic data. We test the correction scheme using a homogeneous model and the Sigsbee2A model. Modeling examples suggest that the use of derived FTDT and ITDT pairs on high-order Lax-Wendroff methods can effectively remove time dispersion errors from high-frequency waves while using longer time steps than allowed in low-order Lax-Wendroff methods. We investigate the influence of the time dispersion on full waveform inversion (FWI) and show an anti-dispersion workflow. We apply the FTDT to source terms and recorded traces before inversion, resulting in that the source and adjoint wavefields contain equal time dispersion from source-side wave propagation, and the modeled and observed traces accumulate equal time dispersion from source- and receiver-side wave propagation. Inversion results reveal that the anti-dispersion workflow is capable of increasing the accuracy of FWI for arbitrary even-order Lax-Wendroff methods. Additionally, the high-order method can obtain better inversion results compared to the second-order method with the same anti-dispersion workflow.

Ground target extraction using airborne streak tube imaging LiDAR

2021 ◽  
Vol 15 (01) ◽  
Author(s):  
Zhiwei Dong ◽  
Yongji Yan ◽  
Yugang Jiang ◽  
Rongwei Fan ◽  
Deying Chen
Keyword(s):  
Target Extraction ◽  
Ground Target ◽  
Streak Tube
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