Fig. 2.

Curvature correction in high numerical aperture lensless imaging. (a and d) Coherent soft x-ray diffraction pattern at 47-nm wavelength (in transmission) before and after curvature correction (maximum momentum transfer of 0.166 nm⁻¹ at the edge of the CCD). (b and e) Magnified diffraction pattern at high diffraction angles showing the radial blurring near the upper-right edge in b, which is absent in e. (c and f) Reconstructed image of waving stick figure without and with curvature correction. The lower width and increased sharpness of the curvature-corrected stick-girl image can be seen in the lineouts shown in c and f Insets.