Ultrahigh-resolution optical coherence tomography with a fiber laser source at 1??m

We report a compact, high-power, fiber-based source for ultrahigh-resolution optical coherence tomography (OCT) near $1\mu \mathrm{m}$. The practical source is based on a short-pulse, ytterbium-doped fiber laser and on generation of a continuum spectrum in a photonic crystal fiber. The broadband emission has an average power of $140\mathrm{mW}$ and offers an axial resolution of $2.1\mu \mathrm{m}$ in air ($<1.6\mu \mathrm{m}$ in biological tissue). The generation of a broad bandwidth is robust and efficient. We demonstrate ultrahigh-resolution, time-domain OCT imaging of in vitro and in vivo biological tissues.