An ultra-small three dimensional computational microscope

We present a computational approach that allows one to create microscopic images in 3D through a miniature, rigid cannula. Light rays propagate from one end of the cannula to the other resulting in a complex intensity distribution. This distribution is unique to the position of the source of the rays. By applying appropriate calibration and utilizing a nonlinear optimization algorithm, we computationally reconstructed images of objects with a minimum feature size of ∼5 μm. Preliminary experiments indicate that the sensitivity of the imaging technique can be as small as 100 nm in the transverse plane and ∼1 μm in the longitudinal direction. Since the cannula is only 14.7 mm long and 200 μm in diameter, this allows for highly miniaturized microscopes that utilize no optics and no scanning. Furthermore, since the images are obtained with just a single frame (no scanning), fast image acquisition is also feasible.