Patent ID: 7486805

Claim:
A method for measuring the topography of a test object comprising the steps of projecting a test pattern consisting of regularly arranged elements onto the surface of a test object, with the recording of an image of the test object with projected test pattern by means of a video camera placed at intervals along a base and with an evaluation of the position of the elements of the test pattern in the image of the test object parallactically displaced by the topography of the test object, where the elements of the test pattern are arranged along at least a first axial direction running at an angle to the base, wherein the angle is determined according to a dissolution power of the video camera, and wherein every element moves with parallactic displacement on its own displacement line running parallel to the projection of the base, said displacement line having no points in common with other displacement lines, and from the position of each element on its displacement line the spatial coordinates of a related point of the test object are determined, whereby the complete test pattern is made up of a limited number of locally bounded elements produced by laser projection in a reference plane, so that the reference plane is selected perpendicular to the optical axis of the video camera in the object space in a reference distance from the projection system, the system parameters of the test object are ascertained from the elements projected in the reference plane, calibration parameters are related to the elements in the reference plane and in projection planes at various distances therefrom, and are filed in a storage system, for measuring the topography, the individual elements are identified with respect to their position within the test pattern and the relevant spatial coordinates are calculated from their position in the image of the test pattern, taking into account the calibration parameters.