Measurement of aspheric surfaces with 3D-deflectometry

Using a high resolution two-dimensional angle sensor, 3D-Deflectometry determines the local slopes of an aspheric surface. The sensor scans the surface in spherical coordinates thus measuring the deviation from a reference sphere. A new fault tolerant software algorithm transfers slope information into surface topography data simultaneously correcting for systematic errors of the instrument. In this way various surface types can be characterized; convex and concave standard shapes as well as toric or even free form surfaces.