Enhance resolution on OCT profilometry measurements using harmonic artifacts

摘要

Optical Coherence Tomography (OCT) systems, as all low coherence interferometry equipments, are mainly grouped in two categories: Time Domain and Frequency Domain, depending on the methodology of data analysis. When measuring samples with high reflectivity, using Frequency Domain systems, detrimental features on OCT images can appear as a replication of a feature at multiple depths on the resulting image, referred as harmonics by the community. This work presents the potential to access better axial resolution and accuracy results on profile measurements analyzing higher harmonics. A variety of measurements of samples with different features, such as roughness, angles and movement evaluation were performed in order to demonstrate the advantages of this approach as a low cost way to have better visualization of reliefs close to the system nominal axial resolution.