Fig. 11: Experimental images from SrTiO3 after denoiser preprocessing.
From: Unsupervised deep denoising for four-dimensional scanning transmission electron microscopy
Virtual dark field STEM images from experimental 4D STEM data acquired using a 1.5 mrad convergence semiangle at (a) high dose and (b) low dose, and c the denoised low dose data. d–f PACBEDs of three small areas for each dataset (the areas indicated with number 1, 2 and 3 correspond to subsets of size 5 × 5 patterns at the location of numbers shown by text in (b), visualising that the denoiser can consistently denoise different structures in the field of view, independently. g–i Similar to (a–c) but now virtual bright field STEM images acquired using a 21.4 mrad convergence semiangle. In both cases the sample is SrTiO3 and the probe spacing is about 60 Å. The denoiser fails in the bottom row due to the absence of geometric flow among patterns, but does reasonably well in the top row. The inset images for (a) and (g) are the corresponding PACBEDs, with the virtual dark field detector locations for (a–c) shown by the red disks in the PACBED inset in (a).
