TIME-RESOLVED INFRARED RADIOMETRY FOR SUBSURFACE INTERFACE IMAGING

We use an algorithm developed for time-resolved infrared radiometry to do pixel-by-pixel calibration of infrared radiometry images and gener ate images of subsurface interfaces. While the approaches described ha ve been previously considered for single point measurements, in this w ork the algorithms are applied to full field images. As a result, imag es presenting defect depth and amount of thermal mismatch at subsurfac e interfaces can be constructed. Results are presented for composite l est panels with flat-bottomed holes milled to different depths and for two-layer specimens with differing thermal properties between the top layer and the substrate.