The scanner performs instant capture of a 3D surface, and after some (fully automated) processing, outputs a 3D model that can be viewed in CAD packages for measurement, or re-printing etc.
The key components are:
a) 4 cameras (to capture the object from different angles).
b) A Multi-view Stereo (MVS) algorithm which turns the 4 images into a 3D model.
c) A projector which projects a random pattern onto the object to help step b.
4 Raspberry Pi Zero's perform synchronised capture and upload images to the cloud ready for processing. A more powerful laptop takes over to create a nicely smoothed, textured mesh.
Essentially, MVS finds matching features in each of the images so that it can triangulate distance. Projecting extra features onto the object results in a more accurate 3D mesh.
It was only designed to capture 3D surfaces at about 6 inches (disregarding the rear of the object and so on), but speed, simplicity and accuracy for this task all score highly.