Figure 8
The local diffraction intensity across a tMLL and wMLL with [epsilon] = 0.5 at the pupil plane. The MLL size is 62 µm, and the zone width varies from 2.5 to 5 nm. The tilting angle is 0.25° for the tMLL and 0° for the wMLL. The section depth is 10.6 µm for the tMLL (to achieve [pi] phase change in two adjacent zones) and 16.5 µm (to achieve an optimal efficiency accounting for dynamical-diffraction effect) for the wMLL. The red curve shows the corresponding phase of the pupil function of the tMLL. The simulation was performed at 20 keV. For a focal length of 10 mm, the diffraction-limited focus size is 10 nm. The inset shows the focus profile for each case.  [article HTML]

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