High-speed in vitro intensity diffraction tomography

We demonstrate a label-free, scan-free intensity diffraction tomography technique utilizing annular illumination (aIDT) to rapidly characterize large-volume 3D refractive index distributions in vitro. By optimally matching the illumination geometry to the microscope pupil, our technique reduces the data requirement by 60x to achieve high-speed 10 Hz volume rates. Using 8 intensity images, we recover similar to 350 x 100 x 20 mu m(3) volumes with near diffraction-limited lateral resolution of 487 nm and axial resolution of 3.4 mu m. Based on the 3D quantitative reconstructions of unicellular diatom microalgae, epithelial buccal cell clusters with native bacteria, and live Caenorhabditis elegans specimens, aIDT shows promise as a powerful high-speed, label-free computational microscopy technique for these applications where natural imaging is required to evaluate environmental effects on a sample in real-time.