Holographic surface imaging for archaeological applications

Abstract

A new approach to precise 3D topometry for medical applications has been applied for the documentation of cultural heritage. The 3D imaging system works with pulsed holography. With a single pulse of a Nd:YLF laser, a surface is recorded with a holographic camera on photosensitive material. The short exposure time of 35 ns allows for high resolution 3D measurement without movement artefacts. The pulsed technique is robust against vibrations and the latest generation of cameras is portable and works at daylight. The holograms are digitized in a second selfcontained unit where the projections of the optically reconstructed real image of the hologram are recorded. Numerical data processing leads to a 3D computer model of the surface with intrinsic gray scale texture. In addition, full-scale daylight copies of the master hologram give an impressive detailed 3D view of the recorded object. The technique is used for 3D imaging of the Windeby Child bog body.