Results 241 to 250 of about 1,058,891 (298)

Anisotropic beam spreading in uniaxial crystals

Optics Communications, 2004
The anisotropic spreading of a paraxial beam propagating orthogonally to the optical axis inside a uniaxial crystal is investigated. The lack of rotational invariance around the propagation direction suggests to consider the mean square width (MSW) of the beam in any transverse direction, which turn out to be a quadratic form of the unit vector ...
Ciattoni a, PALMA, Claudio
openaire   +2 more sources

Some of the next articles are maybe not open access.

Related searches:

Beam-width spreading of vortex beams in free space

2017 International Conference on Optical Instruments and Technology: Optoelectronic Devices and Optical Signal Processing, 2018
Based on the extended Huygens-Fresnel principle and the definition of second-order moments of the Wigner distribution function, the analytical expression for the beam-width spreading of Gaussian Schell-model (GSM) vortex beams in free space are derived, and used to study the influence of beam parameters on the beam-width spreading of GSM vortex beams ...
Meiling Duan, Weiwei Wang, Jinhong Li
exaly   +2 more sources

Beam spreading of vortex beams propagating in turbulent atmosphere

Applied Optics, 2012
We 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, Peter A, Konyaev, Victor A, Sennikov   +2 more
openaire   +2 more sources

Gaussian beam spread in biological tissues

Applied Optics, 1990
Flux density distributions were measured in large tissue sections illuminated with 633- and 1064-nm laser radiation delivered by an optical fiber. The results were modeled by solving the 2-D diffusion approximation for an incident Gaussian beam and fitting the data with nonlinear regression.
L I, Grossweiner, J L, Karagiannes, P W, Johnson, Z, Zhang   +3 more
openaire   +2 more sources

Beam spread function with time dispersion

Applied Optics, 1998
An analytical model for the beam spread function with time dispersion is modeled and validated against Monte Carlo calculations. The model, which is structured on simple statistical concepts and relies on only first and second moments for displacement, angle, and multipath time, is suitable for describing pulsed laser radiation propagation in ...
J W, McLean, J D, Freeman, R E, Walker
openaire   +2 more sources

Importance of beam-beam tune spread to collective beam-beam instability in hadron colliders

Physical Review E, 2004
In hadron colliders, electron-beam compensation of beam-beam tune spread has been explored for a reduction of beam-beam effects. In this paper, effects of the tune-spread compensation on beam-beam instabilities were studied with a self-consistent beam-beam simulation in model lattices of Tevatron and Large Hodron Collider.
Lihui, Jin, Jicong, Shi
openaire   +2 more sources

Beam Spreading in a Turbulent Medium

Journal of the Optical Society of America, 1972
The Kolmogorov spectrum with its associated structure functions is generally used to study wave propagation in turbulent media. It is known, however, that this spectrum does not accurately represent the real atmosphere outside the inertial range. In this paper, the broadening of a focused gaussian beam is calculated, using instead a modified von Karman
J. L. Poirier, D. Korff
openaire   +1 more source

Effective beam energy spreads with molecular ion beams

Nuclear Instruments and Methods, 1978
Abstract For several reasons it is sometimes desirable or necessary to use molecular hydrogen beams to produce nuclear reactions for materials analysis purposes. This paper presents the results of a study of the detailed characteristics of (p, γ) resonance yield curves obtained with molecular beams.
J.W. Butler, C.M. Davisson
openaire   +1 more source

Effect of absorption on the spreading of a laser beam

Optics Letters, 2004
The propagation characteristics of the fundamental Gaussian laser beam in absorptive and active media are investigated. There is a general reduction in the spreading of the beam on propagation in both absorptive and active media. In addition, in an active medium there is a shift of the focal plane and a reduction in the waist size of the beam.
openaire   +2 more sources

Spreading of partially coherent beams in random media

Journal of the Optical Society of America A, 2002
Some published computational work has suggested that partially coherent beams may be less susceptible to distortions caused by propagation through random media than fully coherent beams. In this paper this suggestion is studied quantitatively by examining the mean squared width of partially coherent beams in such media as a function of the propagation ...
Greg, Gbur, Emil, Wolf
openaire   +2 more sources