Precision of quantitative absorption measurement with spectroscopic optical coherence tomography

A state of the art TiAl2O3 laser (λ = 780 nm, Δλ = 170 nm, Pout = 350 mW), interfaced to a free space OCT system was used to quantitatively extract spatially resolved absorption profiles from non-scattering phantoms. The sources of error related to instrument performance and measurement procedure were investigated. Absorption as small as 0.2 mm-1 was measured in phantoms as thin as 180 μm with precision better than 5% over 70 nm wavelength range.