High-precision 3D drift correction with differential phase contrast images.

Single molecule localization microscopy (SMLM) usually requires long image acquisition time at the order of minutes and thus suffers from sample drift, which deteriorates image quality. A drift estimation method with high precision is typically used in SMLM, which can be further combined with a drift compensation device to enable active microscope stabilization. Among all the reported methods, the drift estimation method based on bright-field image correlation requires no extra sample preparation or complicated modification to the imaging setup. However, the performance of this method is limited by the contrast of bright-field images, especially for the structures without sufficient features. In this paper, we proposed to use differential phase contrast (DPC) microscopy to enhance the image contrast and presented a 3D drift correction method with higher precision and robustness. This DPC-based drift correction method is suitable even for biological samples without clear morphological features. We demonstrated that this method can achieve a correction precision of < 6 nm in both the lateral direction and axial direction. Using SMLM imaging of microtubules, we verified that this method provides a comparable drift estimation performance as redundant cross-correlation.