Results 21 to 30 of about 6,648 (171)

Limits of the correction ring applicability in an apodizer with a circular serrated aperture

Компьютерная оптика, 2022
A theoretical investigation has been carried out of the evolution of a monochromatic laser beam profile after the beam exit from an apodizer. The optical scheme of the apodizer consists of a circular serrated aperture with a narrow opaque corrective ring
I.M. Sizova, D.B. Stavrovskii
doaj   +1 more source

Generation of Vortex Optical Beams Based on Chiral Fiber-Optic Periodic Structures

Sensors, 2020
In this paper, we consider the process of fiber vortex modes generation using chiral periodic structures that include both chiral optical fibers and chiral (vortex) fiber Bragg gratings (ChFBGs).
Azat Gizatulin, Ivan Meshkov, Irina Vinogradova, Valery Bagmanov, Elizaveta Grakhova, Albert Sultanov   +5 more
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Performance evaluation and enhancement of apodized fiber Bragg grating for dispersion compensation

AIP Advances, 2021
The apodization function has a significant impact on the state of the art of group delay, dispersion compensation, and acceptable decrease in side lobes in the spectrum of Fiber Bragg Grating (FBG) reflection.
Bassem Adel Naguib, Mohamed Maher Ata, Mahmoud M. Alzalabani, Bedir B. Yousif   +3 more
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Performance optimization of apodized FBG-based temperature sensors in single and quasi-distributed DWDM systems with new and different apodization profiles

AIP Advances, 2013
In this work, different FBG temperature sensors are designed and evaluated with various apodization profiles. Evaluation is done under a wide range of controlling design parameters like sensor length and refractive index modulation amplitude, targeting a
Nazmi A. Mohammed, Taha A. Ali, Moustafa H. Aly   +2 more
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Line Position-Dependent Effect in Line-by-Line Inscribed Fiber Bragg Gratings

Sensors, 2021
Line-by-line direct writing by femtosecond laser has been proved to be a simple and effective method for the fabrication of low-loss fiber Bragg gratings (FBGs), and is more flexible compared with the traditional ultraviolet exposure method.
Hongye Li, Xiaofan Zhao, Binyu Rao, Meng Wang, Baiyi Wu, Zefeng Wang   +5 more
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Quasi-Static Elastography and Ultrasound Plane-Wave Imaging: The Effect of Beam-Forming Strategies on the Accuracy of Displacement Estimations

Applied Sciences, 2018
Quasi-static elastography is an ultrasound method which is widely used to assess displacements and strain in tissue by correlating ultrasound data at different levels of deformation.
Gijs A.G.M. Hendriks, Chuan Chen, Hendrik H.G. Hansen, Chris L. de Korte   +3 more
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The Spherical Harmonic Family of Beampatterns

Acoustics, 2022
The free space solution to the wave equation in spherical coordinates is well known as a separable product of functions. Re-examination of these functions, particularly the sums of spherical Bessel and harmonic functions, reveals behaviors which can ...
Kevin J. Parker, Miguel A. Alonso
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Apodization Optimization of FBG Strain Sensor for Quasi-Distributed Sensing Measurement Applications

Active and Passive Electronic Components, 2016
A novel optimized apodization of Fiber Bragg Grating Sensor (FBGS) for quasi-distributed strain sensing applications is developed and introduced in this paper.
Fahd Chaoui, Otman Aghzout, Mounia Chakkour, Mounir El Yakhloufi   +3 more
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Defocused point spread function of asymmetrically apodized optical imaging systems with slit apertures

Journal of Biomedical Photonics & Engineering, 2016
In the presence of defocusing, the PSF of an optical imaging system with asymmetric apodization have been investigated analytically. The asymmetry in the PSF has been observed to increase with edge strip width (b) of the slit aperture and further ...
Andra Naresh Kumar Reddy, Dasari Karuna Sagar   +1 more
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Systematic comparison of Fiber Bragg Grating pulse compressor designs

Results in Optics
Nine fiber Bragg grating (FBG) pulse compressor designs combining three chirp profiles (linear, quadratic, segmented) with three apodization functions (uniform, Gaussian, raised cosine) are systematically compared using compression ratio (CR).
Wardeh Al-Younis, Mohammed Hussein Bataineh   +1 more
doaj   +1 more source