Multi-channel Fourier domain OCT system with superior lateral resolution for biomedical applications

The lateral resolution of Fourier domain optical coherence tomography (FD-OCT) systems is limited by the depth of focus that can be achieved over the desired imaging depth at the chosen wavelength. Various solutions have been proposed such as Bessel beams and computational methods; however these suffer from various practical drawbacks. We present a novel optical set-up involving multiple optical channels that does not suffer from these drawbacks and delivers at least double the resolution of a single beam system. The theory of this approach is discussed, also the realisation in a practical laboratory system, measurement results and initial application in assessing oesophageal cancers and pre-cancers.