Translation of speckle patterns for highspeed 3D shape measurements

3D shape acquisition is a broad research field. Many approaches exist giving advantages for special applications. In close-range scenarios like quality control, demanding highly accurate reconstructions, stereophotogrammetry including structured illumination is the widely used technique. It is able to achieve high relative accuracies (~1*10-4). Such high relative accuracies are reached by projecting many patterns, typically about 50, for the illumination and therefore the projection rate is an important factor considering highspeed acquistion. Our workgroup developed several high speed approaches to overcome the projection limitation of commonly used DLP projectors for structured illumination purposes. The idea of and the explanations in this talk will cover a projection setup that uses objective laser speckles coming from a diffuser that is illuminated by a laser. The propagating pattern is deflected by a rotating mirror and is used for object illumination. Using highspeed cameras acquiring simultaneously shifted speckle patterns on the object dense, accurate reconstructions of object scenes can be created at ~ 200Hz. Media will substantiate the experimental results shown.