Verfahren und Vorrichtung zur Abstands- und Profilmessung

The method employs three laser sources (1-3) of different wavelengths coupled into a common fibre (4), from the end of which a conical wave enters the glass block (5) of a triangulation interferometer. A beam splitting layer (6) sends symmetrical partial beams through a collimator (9) on to the surface (10) under examination. Precisely one zero-order fringe per wavelength is imaged (11) on a holographic diffraction grating (12) associated with a lens (13) and CCD matrix camera (14). The measurement plane through in-phase points is represented by a stationary electromagnetic field and optically conjugated. USE/ADVANTAGE - On finely machined metallic surfaces such as toothed wheels or turbine blades. Highly improved precision is achievable with better lateral resolution over wider range.