Widefield lensless imaging through a fiber bundle via speckle correlations.
Flexible fiber optic endoscopes provide a solution for imaging at depths beyond the reach of conventional microscopes. Current endoscopes require focusing and/or scanning mechanisms at the distal end, which limit miniaturization, frame rate, and field of view. Alternative wavefront shaping based lensless solutions are extremely sensitive to fiber bending. We present a lensless, bend insensitive, single shot imaging approach based on speckle correlations in fiber bundles that does not require wavefront shaping. Our approach computationally retrieves the target image by analyzing a single camera frame, exploiting phase information that is inherently preserved in propagation through convnetional fiber bundles. Unlike conventional fiber based imaging, planar objects can be imaged at variable working distances, the resulting image is unpixelated and diffraction limited, and miniaturization is limited only by the fiber diameter.
Optics express