The surface shape of a three-dimensional object is acquired with an optical sensor. The sensor, which has a projection device and a camera, is configured to generate three-dimensional data from a single exposure, and the sensor is moved relative to the three-dimensional object, or vice versa. A pattern is projected onto the three-dimensional object and a sequence of overlapping images of the projected pattern is recorded with the camera. A sequence of 3D data sets is determined from the recorded images and a registration is effected between subsequently obtained 3D data sets. This enables the sensor to be moved freely about the object, or vice versa, without tracking their relative position, and to determine a surface shape of the three-dimensional object on the fly.
