Depth Resolved Spectroscopy by Frequency Domain Optical Coherence Tomography

摘要

A new spectroscopic OCT technique is introduced, spectroscopic frequency-domain OCT, and its application to measure depth resolved spectral absorption is described. The crucial parameters of this method like transversal, depth, and spectral resolution and their relations are discussed. As preliminary test of the feasibility of this method, a simple absorbing object, in the present case an IR filter glass plate is investigated. Since the filter attenuates shorter wavelengths stronger than longer ones, one expects a shift of the spectral weight to the IR domain, which is absent in the case of a non-absorbing object like a BK7 glass plate. This effect is demonstrated by the measurement. The results are then compared to theoretical calculations based on the well known characteristics of the filter glass plate.