Results 211 to 220 of about 139,792 (264)
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Optics Letters, 2000
The theoretical diffraction efficiency upper limit of diffractive phase elements (DPE's) with finite apertures is investigated. A successful numerical method of evaluating the efficiency upper bound of DPE's is proposed. The method includes a hybrid optimization procedure that combines a genetic algorithm with the conjugate gradient method.
G, Zhou +4 more
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The theoretical diffraction efficiency upper limit of diffractive phase elements (DPE's) with finite apertures is investigated. A successful numerical method of evaluating the efficiency upper bound of DPE's is proposed. The method includes a hybrid optimization procedure that combines a genetic algorithm with the conjugate gradient method.
G, Zhou +4 more
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Diffraction efficiency of random binary-amplitude diffracting screens
Applied Optics, 1994The diffraction characteristics of random binary-amplitude diffracting screens are investigated. It is shown that, for such a random diffracting screen with complex amplitude transmittance t equal to either 0 or 1, the diffraction efficiency of the screen is maximized when 50% of the screen has transmittance t = 1, independent of other characteristics ...
W T, Rhodes, M S, McMeekin
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Diffractive elements of variable optical power and high diffraction efficiency
Applied Optics, 1993The generation of diffractive elements of variable optical parameters and high diffraction efficiency is presented. It can be realized by a superposition of two conjugate kinoforms. In particular, the method gives rise to zone plates of variable focusing power as well as to circular and linear gratings of variable deflection angles.
A, Kolodziejczyk, Z, Jaroszewicz
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Diffraction efficiency of holographic blazed diffraction gratings
Czechoslovak Journal of Physics, 1991Holographic blazed diffraction grating is analysed as a periodic relief of an inclined sinusoidal curve in the shallow profile approximation. Under the condition that the rate of the development is a linear function of the development dose the evolution of the relief during the development is discussed.
I. Aubrecht, M. Miler
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Effects of diffraction efficiency on the modulation transfer function of diffractive lenses
Applied Optics, 1992Diffractive lenses differ from conventional optical elements in that they can produce more than one image because of the presence of more than one diffraction order. These spurious, defocused images serve to lower the contrast of the desired image. We show that a quantity that we define as the integrated efficiency serves as a useful figure of merit to
D A, Buralli, G M, Morris
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Enhanced diffraction efficiency of gratings in multilayers
Optics Letters, 2000Computations with the rigorous differential method show that single gratings made by ion implantation have a diffraction efficiency in the +1 transmitted order under TE illumination of only 0.78%. The insertion of such gratings into multilayer dielectric Fabry-Perot cavities leads to an enhancement of the free-space diffraction efficiency.
L, Escoubas +4 more
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Performance of diffractive lenses with nonunity diffraction efficiency
Optical Society of America Annual Meeting, 1990The unique optical properties of diffractive optical elements make them attractive candidates for a wide variety of applications. Unlike conventional optical elements, however, diffractive optics can simultaneously produce more than one image, resulting from the various diffracted orders.
Dale A. Buralli, G. Michael Morris
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High-diffraction-efficiency pseudorandom encoding
Journal of the Optical Society of America A, 2000Pseudorandom encoding (PRE) is a statistics-based procedure in which a pure-phase spatial light modulator (SLM) can yield, on the average, the prescribed diffraction pattern specified by the user. We seek to combine PRE with the optimization of an aperture-based target function.
Y, Yang +4 more
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SPIE Proceedings, 2016
In this dissertation, the mathematical model of effect of manufacturing errors including microstructure relative height error and relative width error on diffraction efficiency for the harmonic diffractive optical elements (HDEs) is set up. According to the expression of the phase delay and diffraction efficiency of the HDEs, the expression of ...
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In this dissertation, the mathematical model of effect of manufacturing errors including microstructure relative height error and relative width error on diffraction efficiency for the harmonic diffractive optical elements (HDEs) is set up. According to the expression of the phase delay and diffraction efficiency of the HDEs, the expression of ...
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Balancing diffraction efficiency and laser damage in diffractive optics
Optical Modeling and Performance Predictions IX, 2017Diffractive optics enable applications requiring high power laser focusing and beam shaping. The ability of such components to resist damage is of mounting importance as lasers attain higher power levels. Diffractive optics inherently contain discontinuities that can enhance electric field distributions within the component. Researchers have previously
Steven T. Glass, Thomas J. Suleski
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