Results 271 to 280 of about 67,245 (314)

Optical Quality of Pulsed Electron-Beam Sustained Lasers

Applied Optics, 1974
The optical quality of a pulsed atmospheric CO(2) electric laser is investigated. The density disturbances in the optical cavity are caused by edge waves originating at the anode and cathode. Volumetric heating effects associated with a nonuniform electric discharge are shown to be negligible. The disturbance propagating from the cathode results from a
E R, Pugh, J, Wallace, J H, Jacob, D B, Northam, J D, Daugherty   +4 more
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Improved beam quality in double discharge excimer lasers

Applied Optics, 1977
The cavity configurations of a Tachisto TacII CO/sub 2/ laser, modified for KrF and ArF operation, were varied in order to produce the best beam quality. (AIP)
D L, Barker, T R, Loree
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Continuous-phase elements can improve laser beam quality

Optics Letters, 2000
Siegman [Opt. Lett. 18, 675 (1993)] showed that binary-phase plates cannot improve laser beam quality. We demonstrate that continuous spiral phase elements can improve the quality of beams that originate from a laser operating with a pure high-order transverse mode. A theoretical analysis is presented, along with experimental results obtained with a CO(
R, Oron, N, Davidson, A A, Friesem, E, Hasman   +3 more
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Comparison of phase-aberrated laser beam quality criteria

Applied Optics, 2007
With any form of phase distortions there is the need to qualitatively characterize beam quality. Three different qualitative criteria are most commonly used for this purpose, each of them describing the beam with one ratio: the overlapping integral, the Strehl ratio, and the M2 parameter.
Eugeny, Perevezentsev, Anatoly, Poteomkin, Efim, Khazanov   +2 more
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Beam quality factor for coherently combined fiber laser beams

Optics & Laser Technology, 2009
Abstract The beam quality factor for a coherently combined beam is studied in detail. A theoretical analysis and a numerical calculation are given to illustrate that the M 2 factor is not a proper means for evaluating the beam quality of a coherently combined beam. The beam propagation factor is introduced to evaluate the beam quality.
Pu Zhou, Zejin Liu, Xiaojun Xu, Zilun Chen, Xiaolin Wang   +4 more
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Generalized beam quality factor of aberrated truncated Gaussian laser beams: erratum

Journal of the Optical Society of America A, 2016
A correction is given for Eqs. (10a) and (10b) [J. Opt. Soc. Am. A28, 1372 (2011)JOAOD60740-323210.1364/JOSAA.28.001372].
Cosmas, Mafusire, Andrew, Forbes
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Beam Quality Studies for Intense Beam Free Electron Lasers

1979 International Conference on Submillimeter Waves and Their Applications, 1979
Free electron laser (FEL) experiments conducted to date using intense beams have incorporated cold-cathode, foil-less diodes for beam generation [1,2,3]. Although such beams have been sufficient to demonstrate the basic characteristics of stimulated backscattering, quantitative interpretation of the interaction has suffered from a lack of information ...
R. H. Jackson, R. K. Parker, V. L. Granatstein   +2 more
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Adaptive quality control for laser beam welding

ICALEO '99: Proceedings of the Laser Materials Processing Conference, 1999
The application of laser beam welding within an industrial scope requires parameter close to the task to be performed. Nowadays this is carried out mainly by preliminary investigations with limited generality. The process is influenced by approximately 150 different parameters of direct or indirect action and of systematic or stochastic nature.
M. Dahmen, S. Kaierle, P. Abels, C. Kratzsch, E. W. Kreutz, R. Poprawe   +5 more
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Electron-beam quality in free-electron lasers

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1990
Abstract The equilibrium electron-beam radius in a free-electron laser is determined by the emittance and focussing properties of the wiggler. The spot size of the radiation beam is determined by the optical guiding effects of the interaction. We have obtained a simple relationship connecting the beam emittance and the wavelength, with wiggler ...
C.W. Roberson, B. Hafizi
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Binary phase plates cannot improve laser beam quality

Optics Letters, 1993
Binary phase plates are often suggested as a means for improving the far-field brightness of beams coming from antiphased laser arrays or waveguide lasers operating in higher-order modes. Somewhat surprisingly, however, binary phase plates actually cannot improve at all the second-moment-based beam quality factor M(2) as usually defined for such beams.
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