Dual Core Ytterbium Doped Fiber as a Gain Medium for a High Powered Swept Source Laser for Use in Multi-Channel Optical Coherence Tomography

Optical coherence tomography (OCT) is a novel imaging modality that provides volumetric in-vivo high-resolution (1-15μm) images in real-time. Multi-channel OCT (MOCT) imaging utilizes many imaging channels simultaneously yielding several advantages over single-channel OCT. The benefits of MOCT are at the cost of the added requirement of several imaging beams, which demands high power output from the laser source. Dual-core Ytterbium (Yb) doped fiber was used in two configurations to demonstrate its use as a MOCT light source gain medium: 1) within a ring cavity resonator and 2) in a post-amplification regime with a low powered seed-laser. The amplification wavelength range was tailored to be centered at ~1060nm, where light absorption and scattering is at a minimum in water. In the post-amplification configuration, the output power was increased from 5mW to >200mW, with the axial resolution reducing from 10μm to 12μm. We also present initial in-vivo MOCT imaging of a tadpole.