Kinoform diffractive lenses for efficient nano-focusing of hard X-rays

Opt Express. 2014 Jul 14;22(14):16676-85. doi: 10.1364/OE.22.016676.

Abstract

A nano-focusing module based on two linear Fresnel zone plates is presented. The zone plates are designed to generate a kinoform phase profile in tilted geometry, thus overcoming the efficiency limitations of binary diffractive structures. Adjustment of the tilt angle enables tuning of the setup for optimal efficiency over a wide range of photon energies, ranging from 5 to 20 keV. Diffraction efficiency of more than 50% was measured for the full module at 8 keV photon energy. A diffraction limited spot size of 100 nm was verified by ptychographic reconstruction for a lens module with a large entrance aperture of 440 μm × 400 μm.

Publication types

  • Research Support, Non-U.S. Gov't