Mid-infrared multispectral tissue imaging using a chalcogenide fiber supercontinuum source

We present, to the best of our knowledge, the first demonstration of mid-infrared supercontinuum (SC) tissue imaging at wavelengths beyond 5 μm using a fiber-coupled SC source spanning 2–7.5 μm. The SC was generated in a tapered large-mode-area chalcogenide photonic crystal fiber in order to obtain broad bandwidth, high average power, and single-mode output for diffraction-limited imaging performance. Tissue imaging was demonstrated in transmission at selected wavelengths between 5.7 (1754 cm−1) and 7.3 μm (1370 cm−1) by point scanning over a sub-millimeter region of colon tissue, and the results were compared to images obtained from a commercial instrument.