Electrostatic electron-optical crossed lens with controlled astigmatism

Baranova, L. A.; Read, F. H.
June 1994
Review of Scientific Instruments;Jun94, Vol. 65 Issue 6, p1993
Academic Journal
A crossed lens consisting of square and rectangular apertures in four equally spaced electrodes has been studied. The two inner apertures are rectangular with their longer directions mutually at right angles and the outer apertures are square. The strength and astigmatism of the lens can be separately controlled through the voltages applied to the rectangular apertures, enabling line images of variable position and length to be produced from point objects.


Related Articles

  • Generalized excitation of a coaxial cylindrical lens. Ovsyannikova, L. P.; Fishkova, T. Ya. // Technical Physics Letters;Oct99, Vol. 25 Issue 10, p818 

    Calculations are made of the cardinal elements of a coaxial lens when annular beams are focused onto its axis. An empirical formula is obtained for the excitation of the lens which takes into account its power, and the transverse and longitudinal dimensions, and can be used to obtain simple...

  • Nonlinear surface processes under nonequilibrium TiNi activation by a pulsed electron beam. Tyan, A.; Knyazeva, A.; Psakhie, S. // Russian Physics Journal;Mar2007, Vol. 50 Issue 3, p204 

    Nonlinear processes involved in oxygen diffusion from the adsorption layer into the bulk of an alloy exposed to a low-energy high-current pulsed electron beam are investigated in the framework of a mathematical model accounting for nonequilibrium activation and melting of the irradiated...

  • Source of low-energy coherent electron beams. Daineche, R.; Degiovanni, A.; Grauby, O.; Morin, R. // Applied Physics Letters;1/9/2006, Vol. 88 Issue 2, p023101 

    The coherence of the electron beam emitted at a low applied field from a single micrometer size mineral particle deposited on a carbon membrane is demonstrated by holography experiments. The experimental design combining this electron source with a conventional electrostatic lens system opens a...

  • Focusing inside negative index materials. Brock, Jeffrey B.; Houck, Andrew A.; Chuangt, Isaac L. // Applied Physics Letters;9/27/2004, Vol. 85 Issue 13, p2472 

    Two key theoretical predictions for flat negative index lenses are that thicker lenses should have both internal and external foci, and that these foci should move linearly with small deviations in frequency. Two-dimensional electric field profiles of microwave transmission through rectangular...

  • Transport line for beam generated by ITEP Bernas ion source. Petrenko, S. V.; Kropachev, G. N.; Kuibeda, R. P.; Kulevoy, T. V.; Pershin, V. I.; Masunov, E. S.; Polozov, S. M.; Hershcovitch, A.; Johnson, B. M.; Poole, H. J. // Review of Scientific Instruments;Mar2006, Vol. 77 Issue 3, p03C112 

    A joint research and development program is underway to investigate beam transport systems for intense steady-state ion sources for ion implanters. Two energy extremes of MeV and hundreds of eV are investigated using a modified Bernas ion source with an indirectly heated cathode. Results are...

  • Chromatic aberration of symmetric two-cylinder electrostatic lenses. Vijayakumar, P. S.; Szilagyi, M. // Review of Scientific Instruments;Jun87, Vol. 58 Issue 6, p953 

    Accurate calculations of the axial chromatic aberration coefficients of symmetric two-cylinder bipotential electrostatic lenses for three different gap values (0.10D, 0.50D, and 1.0D) are presented. This is an extension of the first-order properties and the third-order spherical aberration...

  • Electrostatic lenses with very small spherical aberration. Szilagyi, M. // Applied Physics Letters;9/29/1986, Vol. 49 Issue 13, p767 

    A class of electrostatic lenses with extremely low spherical aberration is proposed. The axial potential distribution of these lenses has an asymmetric bell-shaped form with a lower potential on the image side. A lens with Cso∞/fo=0.51 is presented as an example. The maximum required...

  • A new concave electrostatic lens with periodic electrode configuration. Nakata, Shuhei // Review of Scientific Instruments;Jun93, Vol. 64 Issue 6, p1432 

    To obtain a large aperture lens with outstanding focal length homogeneity, a concave electrostatic quadrupole lens with a periodic configuration of the electrodes was developed and its performance was numerically studied. By adjusting the azimuthal angle (θ[sub c]) of the electrode to an...

  • Focusing properties of micron-sized immersion lenses. Schmid, Heinz; Fink, Hans-Werner; Schiller, Christoph; van Rooy, Theo L. // Review of Scientific Instruments;Feb1996, Vol. 67 Issue 2, p375 

    Describes the focusing properties of a two-electrode electrostatic immersion lens of micron dimensions that is combined with the electron point source. Electron microscopy; Design and fabrication of the microlens; Operation; Projection images; Beam quality.


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics