Conclusion

Tilt-corrected bright-field STEM (tcBF-STEM), or parallax imaging, is a dose efficient and accurate 4D-STEM phase contrast imaging technique. By leveraging the principle of reciprocity between tilted TEM and off-axis BF-STEM images, tcBF-STEM enables accurate aberration measurement and correction, improving the imaging of weakly-scattering samples. We have demonstrated the practical application of tcBF-STEM using an iterative cross-correlation and alignment process on a simulated dataset of a protein sample, implemented in our open source py4DSTEM toolkit. We also show how the aligned BF images can be upsampled to produce images with resolution limited by the STEM probe convergence aperture, rather than the the STEM probe sampling limit. tcBF-STEM promises to be a valuable tool for material science and biological TEM research. Future work will focus on refining the tcBF-STEM reconstruction algorithms and exploring real-world applications.