Single-frame randomized probe imaging in the EUV using a high-order harmonic source

We report the demonstration of single-frame randomized probe imaging (RPI) using a 13.5 nm extreme ultraviolet (EUV) beam from a table-top high-harmonic generation (HHG) source. Three types of beams—a smooth, vortex, and speckle beam—were used to investigate the effect of different illuminations on image quality. Single-frame RPI reconstructions were successfully achieved for all beam types, with the highest resolution of 110 nm obtained using the EUV speckle beam. Comparisons with ptychography reconstructions confirm the advantages of structured illuminations over a smooth beam, showing improved convergence and image fidelity. Furthermore, averaging a small number of RPI images reconstructed from individual diffraction patterns significantly improves the resolution to sub-100 nm. These results demonstrate the capability of single-frame RPI to deliver rapid, high-resolution EUV imaging, offering a promising approach for applications limited by acquisition time, such as ultrafast pump-probe studies and real-time feedback.