Continuum generation in a novel photonic crystal fiber for ultrahigh resolution optical coherence tomography at 800 nm and 1300 nm.

Ultrahigh resolution optical coherence tomography (OCT) is demonstrated at 800 nm and 1300 nm using continuum generation in a single photonic crystal fiber with a parabolic dispersion profile and two closely spaced zero dispersion wavelengths. Both wavelengths are generated simultaneously by pumping the fiber with ~78 mW average power at 1064 nm in a 52 MHz, 85 fs pulse train from a compact Nd:Glass oscillator. Continuum processes result in a double peak spectrum with > 110 nm and 30 mW average power at 800 nm and > 150 nm and 48 mW at 1300 nm. OCT imaging with < 5 mum resolution in tissue at 1300 nm and < 3 mum resolution at 800 nm is demonstrated. Numerical modeling of propagation was used to predict the spectrum and can be used for further optimization to generate smooth, broad spectra for OCT applications.