Robust real-time imaging through flexible multimode fibers.

Conventional endoscopes comprise a bundle of optical fibers, associating one fiber for each pixel in the image. In principle, this can be reduced to a single multimode optical fiber (MMF), the width of a human hair, with one fiber spatial-mode per image pixel. However, images transmitted through a MMF emerge as unrecognizable speckle patterns due to dispersion and coupling between the spatial modes of the fiber.

Time-of-flight 3D imaging through multimode optical fibers.

Time-of-flight three-dimensional (3D) imaging has applications that range from industrial inspection to motion tracking. Depth is recovered by measuring the round-trip flight time of laser pulses, typically using collection optics of several centimeters in diameter. We demonstrate near–video-rate 3D imaging through multimode fibers with a total aperture of several hundred micrometers.

Fiber-bundle-basis sparse reconstruction for high resolution wide-field microendoscopy.

In order to observe deep regions of the brain, we propose the use of a fiber bundle for microendoscopy. Fiber bundles allow for the excitation and collection of fluorescence as well as wide field imaging while remaining largely impervious to image distortions brought on by bending. Furthermore, their thin diameter, from 200-500 m, means their impact on living tissue, though not absent, is minimal.