3D Scanner, state of the art

The digital models of real objects are used today in many fields: medicine, archeology and entertainment are some examples of areas in which these models are applied. Generally, the first step of the creation of a real object\u2019s 3D model consists in capturing the geometrical information of the physical object. Real objects can be small as coins or big as buildings: the different requirements have brought to the development of a very variegated set of techniques for the acquisition of geometrical information of the object. The aim of this chapter is to present and explain the techniques the 3D scanners are based on and compare them in terms of accuracy, speed, and applicability, in order to understand advantages and disadvantages of the different approaches