Results 241 to 250 of about 374,145 (293)
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Polarization invariance in beam propagation
Optics Letters, 2007It has been known for some time that the degree of polarization of a light beam may change on propagation, even in free space. In this Letter we derive sufficiency conditions for the degree of polarization of a beam generated by a uniformly polarized stochastic, electromagnetic source of a wide class to be the same throughout the far zone and in the ...
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Microwave and Optical Technology Letters, 1996
A nonorthogonal coordinate system that extends the present range of angled configurations for which the beam propagation method (BPM) is accurate is introduced. This offers an extra degree of freedom within configuration and method when the BPM is applied in the design of general photonic integrated circuits incorporating angled waveguide sections ...
P. Sewell +3 more
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A nonorthogonal coordinate system that extends the present range of angled configurations for which the beam propagation method (BPM) is accurate is introduced. This offers an extra degree of freedom within configuration and method when the BPM is applied in the design of general photonic integrated circuits incorporating angled waveguide sections ...
P. Sewell +3 more
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Wave Propagation in Damaged Beams [PDF]
Studies in the area of ultrasonics have seen the advancement of many industries today. Applications for the use of ultrasound vary from medical treatment and diagnosis to structural health evaluation, to fluid flow measurements systems. Non-Destructive Evaluation (NDE) is one such area that is seeing dramatic improvement in both knowledge and ...
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IEEE Antennas and Propagation Society International Symposium 1992 Digest, 1992
Summary form only given. The authors discussed the application of Fourier transform, finite difference, finite element, real space, multioperator, and Lanczos approaches to paraxial electric field propagation problems in guided-wave optics. Although these methods are generally applied to the Fresnel equation, the authors also considered a class of ...
D. Yevick +3 more
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Summary form only given. The authors discussed the application of Fourier transform, finite difference, finite element, real space, multioperator, and Lanczos approaches to paraxial electric field propagation problems in guided-wave optics. Although these methods are generally applied to the Fresnel equation, the authors also considered a class of ...
D. Yevick +3 more
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Beam spreading of vortex beams propagating in turbulent atmosphere
Applied Optics, 2012We present some results obtained by numerical modeling of the propagation of vortex beams LG(0l) through a randomly inhomogeneous medium. The vortex beams are the lower order Laguerre-Gaussian modes. Such beams, if propagated under conditions of weak turbulence, also experience distortions, like a Gaussian beam.
Vladimir P, Lukin +2 more
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Beam propagation factor of truncated laguerre—gauss beams
Journal of Modern Optics, 2004Abstract Beam propagation factor (usually referred to as M 2 factor) and brightness of high-order symmetrical Laguerre–Gauss (LG) beams that diffract upon a hard-aperture are investigated. We demonstrate that a circular aperture is able to decrease the M 2 factor of a high-order symmetrical LG beam and also to enhance its brightness although losses are
N. Passilly, G. Martel, K. AïT-Ameur
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Journal of Lightwave Technology, 1998
A combined method of the beam propagation method (BPM) and the mode expansion propagation method (MEPM) is proposed for the analysis of reflections of both transverse electric (TE) and transverse magnetic (TM) polarized waves in waveguiding structures containing longitudinal discontinuities.
K. Hayashi +4 more
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A combined method of the beam propagation method (BPM) and the mode expansion propagation method (MEPM) is proposed for the analysis of reflections of both transverse electric (TE) and transverse magnetic (TM) polarized waves in waveguiding structures containing longitudinal discontinuities.
K. Hayashi +4 more
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1999
In the research of optical devices and circuits, a principal theoretical problem is to calculate how a lightwave propagates in an optical medium having an arbitrary refractive-index distribution. Optical waveguide devices are usually very long compared to their transversal dimensions: the ratio is typically of the order of a thousand.
R. Pregla +3 more
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In the research of optical devices and circuits, a principal theoretical problem is to calculate how a lightwave propagates in an optical medium having an arbitrary refractive-index distribution. Optical waveguide devices are usually very long compared to their transversal dimensions: the ratio is typically of the order of a thousand.
R. Pregla +3 more
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Laser beam propagation in turbulent conditions
Applied Optics, 1991Diffraction-limited low power laser beams at 1.06 and 3.8 microm were focused by a 91-cm diam aperture onto a receiver located 10.5 km away on a low slant angle path over a desert basin. The analysis of beam areas and turbulence levels was used to determine a new scaling law for tilt-corrected turbulence-induced beam spread.
S K, Searles +3 more
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Beam propagation and the ABCD ray matrices
Optical Society of America Annual Meeting, 1990We have generalized the propagation law of optical rays through an ABCD optical system by introducing a generalized radius of curvature Q such that„. The real part of the generalized radius of curvature is related to the phase of the beam, and the imaginary part to second moment of the amplitude.
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