Speckle-Interferometrie-Verfahren zur Gewinnung topographischer Informationen von einer Objektoberflaeche sowie dafuer geeignete Speckle-Interferometrie-Vorrichtung

The method involves radiating the object surface (7) from a source (2) with a light beam of wave length lambda which is projected from a radiation head (5, 20, 21) at a first fixed source point relative to the surface. The light scatters at the object surface and passes through an optical system (11, 23) to an opto-electronic sensor where a speckle pattern is generated. A first speckle interferogram is generated by supplying the sensor with a reference beam coherent with the object beam and then a second interferogram is generated with the object radiated from a second point. For each interferogram the light intensity at every point on the sensor image is established and is compared to obtain the topographical information. USE/ADVANTAGE - For qualitative and quantitative determination of deformations on rough surfaces. Uses a single constant radiation wavelength.