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This paper is concerned with the accurate laminary determination of the thickness of coatings on metallic surfaces. The development goal was to devise a system that allows for highly spatially resolved full-frame 2-D scans that conventional systems are not able to provide. Furthermore, it is able to allow for a sufficiently large physical separation between the measuring head and the inspected surface to accommodate industrial environments that provide a high operating velocity and is able to detect quality problems of square millimeter in size. The system consists of a heat source that introduces a thermal transient to the surface layer of the specimen, a thermal imaging system to acquire the time-dependent cooling behavior, and an image processing system to determine thermal parameters indicative of surface quality and/or coating thickness. The results clearly show that a thickness resolution of better than 50 mum can reliably be obtained at a scanning velocity of 0.37 m/s, covering a field of view (FOV) of approximately 200 times 140 mm2.