A 3D scanning device for architectural relieves based on Time-Of-Flight technology

In this work we present the results of some architectural and archaeolog-ical relieves realized by means of a Time-Of-Flight (TOF) laser scanner developed by the Art Diagnostic Group of Istituto Nazionale di Ottica Applicata - INOA (the National Institute of Applied Optics). The instrument is composed of a commercial distance meter mounted on a high precision scanning system, and is equipped with a tripod for total-stations. The device was projected in order to have the following characteristics: reliability, good accuracy and compatibility to other systems. For Cultural Heritage applications it is important to integrate the data acquired with different instruments, but a problem met with many commercial systems is the lack of compatibility with classic survey methodologies. Moreover, superimposition of results from different techniques is possible only if the output is metrically correct. Up to now, the realization of accurate 3D models of buildings was a prerogative of the photogrammetric devices, but the recent progress in opto-electronic technology and 3D software of analysis made possible the production of accurate 3D models. Laser scanning has the main advantage of allowing the acquisition of dense data sampling with high accuracy and high speed.