A 3D scanner, in the simplest terms, is a device that collects the spatial (or geometric) information of any object and uses it to construct its digital 3D model. The mechanism here is to scan (or collect information about) the object from different angles to gain an understanding of relative spatial positions of different points on the object's surface. Once the digital data of multiple scans is obtained, it is used to reconstruct the shape of the object (by using the collected information on relative spatial position of different points). If the color information is collected, then the digital model can also have the colors. This technology is used in a number of areas, including video games and movie-making, prosthetics, reverse engineering and prototype testing. The technology is still in its initial stages and is (relatively) costly. There are also limitations to what can be scanned by a 3D scanner (e.g., shiny surfaces will be difficult to scan, etc.).
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