An interferometric measuring device for measuring the shape of a surface of an object has a radiation source which emits a short-coherent radiation, a beam splitter for forming an object beam which is directed via an object light path to the object and a reference beam which is directed via a reference...http://www.google.ca/patents/US6822746?utm_source=gb-gplus-sharePatent US6822746 - Interferometric, low coherence shape measurement device for a plurality of surfaces (valve seat) via several reference planes
