Scanning surface by projecting modulation pattern - observing surface by optics via second modulation pattern at angle to direction of projection

摘要

The surface examination-method uses a modulation pattern projected onto the surface (11), the latter being examined via a second modulation pattern (13) at a given angle (alpha) to the projection direction. The superimposed modulation patterns provide a line raster from which the surface coordinates are determined. Calibration is achieved by using a reference surface with a number of spaced points with known coordinates. The obtained coordinates are compared with the latter to allow the imaging error to be evaluated and compensated. ADVANTAGE - Simple calibration or correction of surface data derived form object measuring.