نتایج جستجو برای: beam structure

تعداد نتایج: 1665756  

Journal: :Optics letters 2012
F Courvoisier A Mathis L Froehly R Giust L Furfaro P A Lacourt M Jacquot J M Dudley

We use caustic beam shaping on 100 fs pulses to experimentally generate nonparaxial accelerating beams along a 60° circular arc, moving laterally by 14 µm over a 28 µm propagation length. This is the highest degree of transverse acceleration reported to our knowledge. Using diffraction integral theory and numerical beam propagation simulations, we show that circular acceleration trajectories re...

2001
S. Jankovic L. Jankovic A. H. C. Chan G. H. Little

Current numerical methods have slow dynamic visualisation capability, which is usually separate from the calculation phase. This paper investigates whether an analogue virtual reality (VR) model of a structure can integrate calculation and visual representation. The paper shows how the user can interact with a VR analogue model of a cantilever beam, move a concentrated load along the length of ...

2010
J. Li Y. Chen S. Xu Y. Wang M. Zhou Q. Zhao Y. Xin F. Chen

The concept of partially coherent four-petal Gaussian (PCFPG) beam is introduced and described in analytical forms. Based on the Huygens-Fresnel integral formula, average intensity and beam spreading in turbulent atmosphere are derived in analytical expressions. Effects of beam parameters and atmospheric structure constant on intensity distributions and effective beam sizes are investigated in ...

2005
Rong Zhou Eric A. Hansen

We describe a method for transforming beam search into a complete search algorithm that is guaranteed to find an optimal solution. Called beam-stack search, the algorithm uses a new data structure, called a beam stack, that makes it possible to integrate systematic backtracking with beam search. The resulting search algorithm is an anytime algorithm that finds a good, sub-optimal solution quick...

2011
David R. Jackson

Leaky-wave antennas use a traveling wave to radiate continuously along a radiating aperture in order to produce a focused beam of radiation. Planar leaky-wave antennas are particularly attractive since they use simple dielectric layers and/or metallic screens over a grounded substrate layer. A simple source such as a dipole or slot inside the substrate or on the ground plane excites the leaky w...

2014
Feng Lin Isaac M. Markus Marca M. Doeff Huolin L. Xin

The investigation of chemical and structural dynamics in battery materials is essential to elucidation of structure-property relationships for rational design of advanced battery materials. Spatially resolved techniques, such as scanning/transmission electron microscopy (S/TEM), are widely applied to address this challenge. However, battery materials are susceptible to electron beam damage, com...

Journal: :The Review of scientific instruments 2009
Byung Seon Chun Kwangsoo Kim Daegab Gweon

In this research, chromatic confocal microscopy with transverse point beam scanning is constructed for three-dimensional surface measurement without longitudinal mechanical translation. In beam scanning chromatic confocal microscopy, the wavelength-to-depth relation and the lateral field of view should be determined considering the beam scanning angle. With the experimental results from a sampl...

2004
Daniele C. E. Bortolotti John L. Bohn

We consider the problem of an atomic beam propagating quantum mechanically through an atom beam splitter. Casting the problem in an adiabatic representation (in the spirit of the Born-Oppenheimer approximation in molecular physics) sheds light on explicit effects due to nonadiabatic passage of the atoms through the splitter region. We are thus able to probe the fully three-dimensional structure...

1999
Y. Kang G. Decker

The APS storage ring beam chamber has been storing the beam up to 100 mA successfully. However, in some beam chambers, spurious signals corrupted the BPM outputs. The cause of the unwanted signals was investigated, and it was found that transverse electric (TE) longitudinal harmonic resonances of the beam chamber were responsible. The beam chambers have small height in the area between the oval...

Journal: :Applied optics 2014
Yana V Izdebskaya Ting-Hua Lu Dragomir N Neshev Anton S Desyatnikov

We study numerically and demonstrate experimentally a novel type of singular optical beams formed by the phase imprinting of an optical vortex into the structure of the three-Airy beams. In contrast to a vortex-free product of three Airy beams, in this type of singular-Airy beam, the vortex in the beam axis causes a twist in the beam transverse intensity profile with propagation. Such a new typ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید