Optical coherence tomography (OCT) is an emerging technique for imaging of synthetic materials. OCT is attractive because of the combination of its high sensitivity (>90 dB), high resolution ((10-20) mm), and low cost (~$75 k). The value of any new technology is evaluated by how well it compares with existing ones. In this work, impact damage of an epoxy/E-glass composite is imaged using OCT. The results were compared with micro-focus x-ray computed tomography, which is considered to be the benchmark to which OCT is measured because of its ability to locate features precisely with a comparable resolution. OCT is considered to be a confocal technique and was compared to an analogous technique, laser scanning confocal microscopy. Contrast mechanisms, sensitivity, resolution, depth of penetration, and artifacts between the techniques are compared and contrasted. Also, damage mechanisms revealed using OCT are briefly discussed.
Citation: Ndt & E International
Volume: 78 No. 2
Pub Type: Journals
composites, confocal microscopy, damage, non-destructive evaluation, optical coherence tomography, x-ray tomography