A probing retroreflector for determining the location and dimensions of a target in conjunction with optical measuring systems, such as tracking laser interferometers. The probing retroreflector comprises a support, a retroreflector assembly coupled to the support and having a center point, a planar...http://www.google.de/patents/US5530549?utm_source=gb-gplus-sharePatent US5530549 - Probing retroreflector and methods of measuring surfaces therewith
