There exist, online, resources and instructions on building your own DIY (do-it-yourself) 3D scanner. All you need is: a webcam, a sight-line laser and white foam-core board. The webcam will watch how the laser falls across the object being scanned and the white backing, to triangulate individual points in space. The board has an alignment pattern that the camera also sees, so that the program understands the spacial orientation of any laser lines that it will see. The concept is quite ingenious. A commercial scanner will cost you hundreds of dollars. The DIY version does the same thing, though it is a tad temperamental to work with. My friend, Donovan, lent his assistance with the project. We used a deer skull for our scan subject. The software available for this project, as well as instructions and support can be found at http://www.david-laserscanner.com .
A green laser is recommended; all we had to work with was a red laser. And the laser has to be a sight-line laser, that is, a laser that beams a spread of light, instead of a single point. The spread projects a line across the object being scanned. It makes it possible to observe the angles that exist between the object being scanned, and the backdrop. The backdrop must be a 90-degree corner with the calibration pattern. It can be any scale. When a scan starts, the operator sweeps the laser across the object, and the image will take shape on the computer screen. Since the camera and object must remain stationary, only one side of the object can be scanned at a time. After a scan is complete, the 3-dimensional representation of the face can be viewed from different angels. Once all of the scans are completed, the the sides can be combined to form the final object, viewable from any angle. This software even has the ability to take an image snapshot of the face, to wrap the model with. So that colors and textures can be represented. I didn’t happen to play with that feature. And also, since I’m only working off of the trial software, my scans are significantly limited in resolution.
I do 3D modeling for hobby. This has been a neat experience and a fascinating tool to try out.