Assessment of lower-voltage TEM performance using 3D Fourier transform of through-focus series

► We assess the performance of TEM using 3D Fourier transform of through-focus images. ► The method can discriminate between the linear and non-linear TEM imaging terms. ► High resolution of 98 pm is achieved using 80 kV Cs-corrected TEM with monochromator. ► We also revisit the Young fringe method in the light of the 3D Fourier transform.