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Electrochemical Etching and Characterization of Sharp Field Emission Points for Electron Impact Ionization
Published on: July 12, 2016
On focused fields with maximum electric field components and images of electric dipoles
R de Bruin1, H P Urbach, S F Pereira
1Optics Research Group, Department of Imaging Science and Technology, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands.
Abstract:
We study focused fields which, for a given total power and a given numerical aperture, have maximum electric field amplitude in some direction in the focal point and are linearly polarized along this direction. It is shown that the optimum field is identical to the image of an electric dipole with unit magnification. In particular, the field which is the image of an electric dipole whose dipole vector is parallel to the optical axis, is identical to the field whose longitudinal component is maximum at the image point.
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