Broadband Fourier domain mode-locked laser for optical coherence tomography at 1060 nm

Optical coherence tomography (OCT) in the 1060 nm range is very interesting for imaging the human retina and the underlying layers (choroid, sclera) due to low absorption in water and good penetration through the retinal pigment epithelium. Especially, swept source OCT (SS-OCT) enables ultra-high imaging speed if an appropriate rapidly tunable light source is used. For instance, with a state-of-the-art Fourier domain mode-locked (FDML) laser, densely sampled 3D dataset covering a wide field of view can be acquired within a few seconds. The typical gain media for fast swept sources are semiconductor optical amplifiers (SOAs) which feature fast gain dynamics enabling rapid wavelength tuning and a broad tuning bandwidth. These factors are important for OCT in order to achieve high imaging speeds and good depth resolution.