THREEDIMENSIONAL OPTICAL MEASUREMENT OF T EETH

A special optical 3D-measurement technique allows to measure in vivo t he shape of teeth or tooth-cavities with adequate precision, because t he sensor can be miniaturized and aquisition time can be fast. A syste m based on the Phase-Shifting-Triangulation technique has proven to be suitable and reliable in daily use in the dental practice. The system may serve as an example for high performance of optical 3D-measuremen t techniques even under very restricted conditions. By using optical a nd electronical subsystems, which has been developed especially for th e application, a system has been created, which can measure surfaces i n a volume of 14 mm x 17 mm x 12 mm in 0.133 s. The sensor can be plac ed in a human mouth, oriented for measurement and stabilized during aq uisition by hand of the dentist. The accuracy of the measurement in ap plication relevant volumes is +/-25 mu m.