[1. KUREPA, M. V., TASIC, M. D. and KUREPA, J. M. 1974. A four element energy scanning electron lens system with fixed image position and magnification. J. Phys. E: Sci. Instrum., 7, 940-4.]Search in Google Scholar
[2. KISKER, E. 1982. Simple method for accurate ray tracing in electrostatic lenses. Rew. Sci. Instrum., 53, 114-7.]Search in Google Scholar
[3. BERTRAM, S. 1940. Proceedings of the Institution of Radiation Engineers. 28, 418-420.]Search in Google Scholar
[4. IMHOF, R. E. and READ, F. H. 1968. A three-aperture electron optical lens for producing an image of variable energy but fixed position. J. Phys. E: Sci. Instrum., 1, 859-60, 1968.]Search in Google Scholar
[5. READ, F. H. 1970. Asymmetric electrostatic lenses of three aperture. J. Phys. E: Sci. Instrum., 3, 127-31.]Search in Google Scholar
[6. EL-KAREH A. B. and STURANS M. A. 1971b. Analysis of the 3-Tube Asymmetrical Unipotential Lens. J. Appl. Phys., 42, 4902-7.]Search in Google Scholar
[7. EL-KAREH, A. B. and EL-KAREH, J. C. J. 1970. Electron Beams, Lenses and Optics vols 1 and 2. London: Academic Press.10.1016/B978-0-12-238001-3.50005-X]Search in Google Scholar
[8. READ, F. H. 1969a. Accurate calculations of double-aperture electrostatic immersion lenses. J. Phys. E: Sci. Instrum, 2, 165-169.]Search in Google Scholar
[9. EL-KAREH A. B. 1969. Rec. 10.th Symp. Electron, Ion and Laser Beam Technology. ed L Marton. San Francisco: San Fransisco Press, 393-6.]Search in Google Scholar
[10. READ, F. H. 1971. Electrostatic cylinder lenses III: Three element asymmetric voltage lenses. J. Phys. E: Sci.Instrum., 5, 156-160.]Search in Google Scholar
[11. KODAMA, M. 1981. An improvement to the variational method for boundary value problems and its application to two-cylinder electrostatic lenses. J. Phys. D: Appl. Phys. 15, 1657-66.]Search in Google Scholar
[12. READ, F. H. 1971. Zero gap electrostatic aperture lenses. J. Phys. E: Sci. Instrum. 4 562-6.10.1088/0022-3735/4/8/003]Search in Google Scholar
[13. RENAU A., READ F. H. and J BRUNT, N. H. 1982. The Charge Density Method of solving electrostatic problems with and without the inclusion of space-charge. J. Phys. E: Sci. Instrum, 15, 347-354.]Search in Google Scholar
[14. Van HOOF, H. A. 1980. An electrostatic lens for polar-angle selection of photoemitted electrons. J. Phys. E: Sci. Instrum, 14, 325-29.]Search in Google Scholar
[15. HARTING, E. and READ, F. H. 1976. Electrostatic Lenses. Amsterdam: Elsevier.]Search in Google Scholar
[16. MUNRO, E. 1971. Electron Microscopy and Analysis. W C Nixon. London: Institute of Physics, 84-5.]Search in Google Scholar
[17. MUNRO, E. 1970. Proc. 7th Cong. Electron Microscopy. Grenoble ed P Favard, 55-6.]Search in Google Scholar
[18. MUNRO, E. 1971. PhD Thesis. University of Cambridge.]Search in Google Scholar
[19. HEDDLE, D.W.O. 1999. Accurate calculation of cylinder lens potentials using the ninepoint relaxation and Bessel expansion methods. J. Phys. D: Appl. Phys., 32, 1447-54.]Search in Google Scholar
[20. NATALI, S., Di CHIO, D. and KUYATT, C.E. 1972. Accurate Calculations of Properties of the Two-Tube Electrostatic Lens: I. Improved Digital Methods for the Precise Calculation of Electric Fields and Trajectories. J. Research of the National Bureau of Standards, 76A, 27-35.]Search in Google Scholar
[21. EDWARDS Jr., D. 1983. Accurate calculations of electrostatic potentials for cylindrically symmetric lenses. Rev. Sci. Inst., 54, 1729-35.]Search in Google Scholar
[22. COOK, R. D. and HEDDLE, D. W. O. 1976. The simple accurate calculation of cylinder lens potentials and focal properties. J. Phys. E: Sci. Instrum., 9, 279-82.]Search in Google Scholar
[23. J. R. PIERCE. 1954. Theory and Design of Electron Beams. (Chapters VI, VII), 2nd ed. New York: Van Nostrand.]Search in Google Scholar
[24. KLEMPERER, O., BARNETT, M. E. 1971. Electron Optics. (Chapters 2, 3), 3rd ed. Cambridge: Cambridge University Press. ]Search in Google Scholar