1. A method for optically scanning a three-dimensional geometry of an object by means of a triangulation method, a pattern being projected onto the object to be scanned, in order to obtain a 3D data set and the projected pattern is recorded in an image, the method comprising: projecting a first pattern on the object to be scanned, to create at least one first image; projecting a second pattern, which deviates from the first pattern as regards position or shape, on the object to be scanned, to create at least one second image; merging 3D data acquired from the first image and from the second image, to form a 3D data set; projecting a correlating pattern onto the object to be scanned to create at least one correlating image, wherein the correlating image, the at least one first image, and the at least one second image are oriented relatively to each other in such a manner that the at least one first image and the at least one second image each have, with the correlating image, at least one common point illuminated by both the correlating pattern and the first pattern or the second pattern, respectively, and recorded in the at least one first image or the second image, respectively, and the correlating image; and merging the 3D data with the 3D data set, on the basis of 3D data acquired from the first image, the second image, and the correlating image, respectively, at the at least one common point, such that 3D data acquired from the first and second images at the at least one common point each agree with the 3D data acquired from the correlating image at the at least one common point, wherein the first pattern and the second pattern exhibit parallel light stripes oriented in a first direction, wherein the correlating pattern exhibits light stripes oriented in a second direction which differs by a given angle of at least 5° and not more than 90° with respect to the first direction in which the first and second patterns in the first and the second images are oriented, wherein the at least one common point is formed by at least one point of intersection between the light stripes in the first or second pattern in the first or second image, respectively, and the light stripes in the correlating pattern in the correlating image, wherein the correlating image containing light stripes oriented in the second direction shows greater spacing of light stripes than in the first and second images containing light stripes oriented in the first direction, and wherein at least one of the above merging steps is performed by an evaluation unit.