Device and method for spatially measuring surfaces

A device for spatially measuring surfaces, comprising:

• a projector for projecting patterns into an object space, two cameras for recording pictures of a surface in the object space, said surface to be measured, and a control and evaluation unit for activating the cameras and for evaluating the pictures recorded by these,
• wherein the projector comprises a light source, a projection lens and at least one rotatably arranged pattern structure as an imaging element, as well as a drive for rotating the at least one pattern structure,
• wherein the at least one pattern structure has a form of one of a rotatable disc, a rotatable cylinder surface, and a closed rotating belt which is led around at least two rollers and rotatable in a longitudinal direction of the belt by rotating the rollers,
• wherein the pattern structure comprises an aperiodic strip pattern with strips oriented in a radial direction of the disc or parallel to a symmetry axis of the cylinder surface or transversely to the longitudinal direction of the belt,
• wherein the control and evaluation unit is configured to carry out the following steps:
• activating the cameras for simultaneously recording pictures at each of a multitude of successive points in time of recording, so that a sequence of brightness values is acquired for points in picture planes of the cameras;
• identifying corresponding points in the picture planes of the cameras, by way of evaluating a correlation function between the sequences of brightness values acquired for potentially corresponding points and maximizing a value of a thus formed correlation;
• and
• determining spatial coordinates of surface points on the surface by way of triangulation on the basis of the points identified as being corresponding.