Thermal pattern generation for infrared deflectometry

Operating in the visible spectrum, the method of deflectometry provides reliable surface-slope measurements. We present the extension of the method to the thermal infrared (IR) spectrum, thus enabling the deflectometric inspection of rough surfaces and objects made of transparent and nonspecular materials. Since affordable technologies to create code patterns in the thermal IR do not exist, we propose a novel method to produce large-scale dynamic thermal patterns with the help of a powerful laser. In addition, we adapted coded pattern techniques to our setup and present the results of deflectometric measurements.