Search for: All records

Fiber bundles have become widely adopted for use in endoscopy, live-organism imaging, and other imaging applications. An inherent consequence of imaging with these bundles is the introduction of a honeycomb-like artifact that arises from the inter-fiber spacing, which obscures features of objects in the image. This artifact subsequently limits applicability and can make interpretation of the image-based data difficult. This work presents a method to reduce this artifact by on-axis rotation of the fiber bundle. Fiber bundle images were first low-pass and median filtered to improve image quality. Consecutive filtered images with rotated samples were then co-registered and averaged to generate a final, reconstructed image. The results demonstrate removal of the artifacts, in addition to increased signal contrast and signal-to-noise ratio. This approach combines digital filtering and spatial resampling to reconstruct higher-quality images, enhancing the utility of images acquired using fiber bundles. 

In this Letter, we report a low-cost, portable, two-photon excitation fluorescence microscopy imager that uses a fiber-based approach for both femtosecond supercontinuum (SC) generation and light delivery to the optical head. The SC generation is based on a tapered polarization-maintaining photonic crystal fiber that uses pre-chirped femtosecond narrowband pulses to generate a coherent SC spectrum with a bandwidth of approximately 300 nm. Using this approach, high-power, near-transform-limited, wavelength-selectable SC pulses are generated and directly delivered to the imaging optical head. Preliminary testing of this imager on brain slices is presented, demonstrating a high signal-to-noise ratio and sub-cellular imaging capabilities to a depth of approximately 200 µm. These results demonstrate the suitability of the technology forex vivoand potentiallyin vivocellular-level biomedical imaging applications.