Method and apparatus for the three-dimensional measurement of the shape and the local surface normal of preferably specular objects

#This application claims the priority, under 35 U.S.C. §119, of European application EP 07005091.9, filed Mar. 13, 2007; the prior application is herewith incorporated by reference in its entirety.

#1. Field of the Invention

#3D sensors for the three-dimensional detection of shape are used in many applications. The measurement of specular surfaces is also possible with optical sensors. Surfaces of spectacle lenses or car windshields are examples thereof.

#FIG. 1 is a diagrammatic, partly sectional, side-elevational view of a camera, measurement object and extended lighting device, illustrating the principle of deflectometry;

#FIG. 2 is an elevational view of a virtual screen with imaginary strip-like pixels;

#FIG. 3 is a view similar to FIG. 1 along with a front-elevational view, illustrating a first embodiment of the invention;

#Referring now to the figures of the drawings in detail, the following consideration results in embodiments of the invention without a video projector:

#If the required light structures on the screen are changeably horizontal or vertical strips, the full resolution of a television or monitor of approximately 1000*1000=1 million pixels in principle is not required.

#FIG. 2 shows that if there were a display with 1000 vertical “strip-like pixels” which can be superimposed in any way with 1000 horizontal virtually “strip-like pixels” 9, the lighting device could be realized with 2000 pixels instead of 1 million pixels on a virtual screen 5.