Ultrahigh-resolution optical coherence tomography using continuum generation in an air–silica microstructure optical fiber

We demonstrate ultrahigh-resolution optical coherence tomography (OCT) using continuum generation in an air–silica microstructure fiber as a low-coherence light source. A broadband OCT system was developed and imaging was performed with a bandwidth of 370 nm at a $1.3‐\mu \mathrm{m}$ center wavelength. Longitudinal resolutions of $2.5 \mu \mathrm{m}$ in air and $\sim 2 \mu \mathrm{m}$ in tissue were achieved. Ultrahigh-resolution imaging in biological tissuein vivo was demonstrated.