Figure 4

Typical measured results of superfocusing.

(a–d) are experimentally recorded SH patterns at different observation distances, where the insets are the enlarged images of the selected focused spots. The cross-sections of the selected focused spots in (a–d) are given, respectively, in (e–h), whose centers are fitted with a Lorentzian (e–g) or Gaussian (h) lineshape. The black dots in (e–h) are experimental data. (i–l) are theoretical simulations corresponding to (a) – (d), respectively.