Figure 8
The global degree of coherence (black line) and the focal size (red line) as functions of the beam-defining aperture size [\Omega_{\rm{A}}] in the horizontal (a) and vertical (b) directions. The dashed line indicates a highly coherent beam with the coherence length in the focus being twice as large as the r.m.s. beam size, [\xi_{\rm{F}}] = [2\sigma_{\rm{F}}]. (c) The increase in the flux density IPeak as a function of the beam-defining aperture size in the horizontal (blue dashed line) and vertical (green dotted line) directions.  [article HTML]