Method and device for non-contact testing of materials for inhomogeneities

摘要

To carry out non-contact material testing for inhomogeneities, the material is exposed to irradiation with light which induces a photothermal effect. A local temperature rise associated therewith is detected by the deflection of a scanning laser beam, either due to the mirage effect (for a flat material surface) or by the change in direction of the reflected laser beam if the temperature increase causes mechanical expansion on the material surface (for an uneven, reflecting material surface).