C. M. Blanca, J. Bewersdorf and S. W. Hell, "Single sharp spot in fluorescence microscopy of two opposing lenses," Appl. Phys. Lett. 79, 2321-2323 (2001).
S. S. Sherif and P. Török, "Pupil plane masks for super-resolution in high-numerical-aperture focusing," J. Mod. Opt. 51, 2007-2019 (2004).
S. Lindek, J. Swoger and E. H. K. Stelzer, "Single-lens theta microscopy: resolution, efficiency and working distance," J. Mod. Opt. 46, 843-858 (1999).
C. Ibáñez-López, I. Escobar, G. Saavedra and M. Martínez-Corral, "Optical sectioning improvement in two-color excitation scanning microscopy," Microsc. Res. Tech. 64, 96-102 (2004).
Abbe, E. Arch. Mikrosk. Anat. 9, 413�??468 (1873).
S. Kawata, H.-B. Sun, T. Tanaka and K. Takada, "Finer features for functional microdevices," Nature 412, 697-698 (2001).
D. G. Grier, "A revolution in optical manipulation," Nature 424, 810-816 (2003).
O. Haeberlé, �??Focusing of light through a stratified medium: a practical approach for computing microscope point spread functions. Part I: Conventional microscopy,�?? Opt. Commun. 216, 55-63 (2003).
M. Martínez-Corral, M. T. Caballero, E. H. K. Stelzer and J. Swoger, "Tailoring the axial shape of the point spread function using the Toraldo concept," Opt. Express 10, 98-103 (2002).
C. M. Blanca and S. W. Hell, "Axial superresolution with ultrahigh aperture lenses," Opt. Express 10, 893-898 (2002).
M. Martínez-Corral, C. Ibáñez-López, G. Saavedra and M. T. Caballero, "Axial gain in resolution in optical sectioning fluorescence microscopy by shaded-ring filters," Opt. Express 11, 1740-1745 (2003).
T. R. M. Sales, "Smallest focal spot," Phys. Rev. Lett. 81, 3844-3847 (1998).
J. Miao, T. Ishikawa, B. Johnson, E. K. Anderson, B. Lai and K. O. Hodgson, "High resolution 3D x-ray diffraction microscopy," Phys. Rev. Lett. 89, 088303 (2002).
J. Miao, T. Ohsuna, O. Terasaki, K. O. Hodgson and M. A. O�??Keefe, "Atomic resolution three-dimensional electron diffraction microscopy," Phys. Rev. Lett. 89, 155502 (2002).
M. Dyba and S. W. Hell, "Focal spots of size lambda/23 open up far-field fluorescence microscopy at 33 nm axial resolution," Phys. Rev. Lett. 88, 163901 (2002).
T. A. Klar, S. Jakobs, M. Dyba, A. Egner and S. W. Hell, "Fluorescence microscopy with diffraction resolution barrier broken by stimulated emission," Proc. Natl. Acad. Sc. 97, 8206-8210 (2000).
W. Denk, J. H. Strickler and W. W. Webb, "Two-photon laser scanning fluorescence microscopy," Science 248, 73-76 (1990).
B. Bailey, D. L. Farkas, D. Lansing-Taylor and F. Lanni, "Enhancement resolution in fluorescence microscopy by standing-wave excitation," Science 366, 44-48 (1993).
J. Huisken, J. Swoger, F. Del Bene, J. Wittbrodt and E. H. K. Stelzer, "Optical sectioning deep inside live embryos by selective plane illumination microscopy," Science 305, 1007-1009 (2004).
J. B. Pawley, ed., Handbook of biological confocal microscopy. Plenum Press, New York, 1995.
The term superresolution introduced here is understood in the sense of Rayleigh criterion; i. e., as the narrowness of the PSF or, equivalently, the enhancement of the OTF for frequencies under the cut-off frequency.
The eccentricity is defined here as e = �??(1-b^2 / a^2) , where a and b account for the lengths of the semimajor and semiminor axes, respectively.
B. Richards and E. Wolf, Proceedings of the Royal Society (London) A 253, 358 (1959).