Subsurface Defect Localization by Structured Heating Using Laser Projected Photothermal ThermographyErik Thiel 1, Mathias Ziegler 1
1Department for Non-Destructive Testing, Thermographic Methods, Bundesanstalt für Materialforschung und -prüfung (BAM)
This method aims at locating vertical subsurface defects. Here, we couple a laser with a spatial light modulator and trigger its video input to heat a sample surface deterministically with two anti-phased modulated lines while acquiring highly resolved thermal images. The defect position is retrieved from evaluating thermal wave interference minima.
