Results 261 to 270 of about 77,582 (319)
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Journal of Modern Optics, 2004
The oblique incidence of a He-Ne laser beam onto a phase-only diffractive optical element (DOE) that simultaneously produces several unimode different-order Bessel beams propagating at various angles with respect to the optical axis is studied theoretically and experimentally.
S. N. Khonina +5 more
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The oblique incidence of a He-Ne laser beam onto a phase-only diffractive optical element (DOE) that simultaneously produces several unimode different-order Bessel beams propagating at various angles with respect to the optical axis is studied theoretically and experimentally.
S. N. Khonina +5 more
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Journal of the Optical Society of America A, 2012
An analytical solution of the scalar Helmholtz equation to describe the propagation of a laser light beam in the positive direction of the optical axis is derived. The complex amplitude of such a beam is found to be in direct proportion to the product of two linearly independent solutions of Kummer's differential equation.
Victor V, Kotlyar +2 more
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An analytical solution of the scalar Helmholtz equation to describe the propagation of a laser light beam in the positive direction of the optical axis is derived. The complex amplitude of such a beam is found to be in direct proportion to the product of two linearly independent solutions of Kummer's differential equation.
Victor V, Kotlyar +2 more
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Superresolution laser beam shaping
Applied Optics, 2004The superresolution technique is well known for its ability to compress the central diffractive spot that is smaller than the Airy diffractive spot. In this paper, we extend the superresolution technique for different laser beam shaping. A complete set of superresolution diffractive elements is developed for the flat-top beam shaping, the single-circle
Jia, Jia +3 more
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Holographic Laser Beam Deflector
Applied Optics, 1975A mechanically rotating laser beam deflector is described that consists of several transmission type volume holograms recorded on a cylindrical surface. Its performance characteristics are compared with those of a multifacetted rotating mirror.
R V, Pole, H P, Wollenmann
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2020
In atoms, the electron orbits around the nucleus are quantized, occur for discrete energies. Transitions between energy levels require absorption or emission of photons. In the case of an unusual occupation of excited levels, individual photons can trigger a coherent transition of all such levels to the ground state, thus leading to a beam of coherent ...
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In atoms, the electron orbits around the nucleus are quantized, occur for discrete energies. Transitions between energy levels require absorption or emission of photons. In the case of an unusual occupation of excited levels, individual photons can trigger a coherent transition of all such levels to the ground state, thus leading to a beam of coherent ...
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Applied Optics, 1978
A two-mirror laser beam expander can be used to provide small amounts of beam steering by moving one mirror. Such a motion would generally introduce aberrations into the output wavefront that would restrict the amount of diffraction-limited beam steering achievable to very small amounts.
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A two-mirror laser beam expander can be used to provide small amounts of beam steering by moving one mirror. Such a motion would generally introduce aberrations into the output wavefront that would restrict the amount of diffraction-limited beam steering achievable to very small amounts.
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1985
Much of the development work in laser systems is in the area of delivery devices, i.e. how the light is delivered to the desired target. Delivery devices can create a significant overlap in the effects and applications of the various types of laser systems, remembering that the ultimate laser — tissue interaction mechanism is tissue heating.
Gregory T. Absten, Stephen N. Joffe
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Much of the development work in laser systems is in the area of delivery devices, i.e. how the light is delivered to the desired target. Delivery devices can create a significant overlap in the effects and applications of the various types of laser systems, remembering that the ultimate laser — tissue interaction mechanism is tissue heating.
Gregory T. Absten, Stephen N. Joffe
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Focusing elliptical laser beams
Applied Optics, 1984The spot formed by focusing an elliptical laser beam through an ordinary objective lens can be optimized by properly filling the objective lens. Criteria are given for maximizing the central irradiance and the line-spread function. An optimized spot is much less elliptical than the incident laser beam.
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1989
Abstract Laser beam machining removes, melts, or thermally modifies a material by focusing a coherent beam of monochromatic light on the workpiece. This article describes the principal lasers used in metal processing: neodymium-glass, carbon dioxide, and neodymium-doped yttrium aluminum garnet lasers.
Dana Elza, Gene White
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Abstract Laser beam machining removes, melts, or thermally modifies a material by focusing a coherent beam of monochromatic light on the workpiece. This article describes the principal lasers used in metal processing: neodymium-glass, carbon dioxide, and neodymium-doped yttrium aluminum garnet lasers.
Dana Elza, Gene White
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1993
AbstractLaser-beam welding (LBW) uses a moving high-density coherent optical energy source, called laser, as the source of heat. This article discusses the advantages and limitations of LBW and tabulates energy consumption and efficiency of LBW relative to other selected welding processes.
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AbstractLaser-beam welding (LBW) uses a moving high-density coherent optical energy source, called laser, as the source of heat. This article discusses the advantages and limitations of LBW and tabulates energy consumption and efficiency of LBW relative to other selected welding processes.
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