Tunable quasi-supercontinuum generation in a 1.7 µm spectral band for spectral domain optical coherence tomography

Abstract

We present a system for generating a 1.7 µm quasi-supercontinuum (SC) as what we believe to be a new broadband light source for spectral domain (SD) optical coherence tomography (OCT). The quasi-SC source, whose spectral range and spectral shape can be arbitrarily changed, is based on wavelength-tunable soliton pulse generation and high-speed intensity modulation. A Gaussian-shaped quasi-SC was introduced into an SD-OCT system. A maximum axial resolution of 14 µm in air (corresponding to 10 µm in tissue) and an imaging sensitivity of 94 dB was obtained. We also demonstrated high-resolution imaging for tape stack, human nail and pig thyroid gland samples using a quasi-SC. From these results, we confirmed the usefulness of a quasi-SC for SD-OCT imaging.