3D scanner: 3D scanning implies analyzing the real-world environment or objects for collecting data on their appearance, i.e. color and shape. Digital 3D models can be constructed from the data collected. Such devices are being used by the amusement industry extensively for producing video games and movies. This technology is more widely used in reverse engineering, industrial design, prototyping, keeping records of cultural artifacts, and computer vision. A number of technologies have been used for building the three-dimensional scanning devices. Every technology has limitations, costs, and advantages.
Functionality: The idea behind using a three-dimensional scanner is creating a Point Cloud of the Geometric Samples on the subject's surface. The subject's shape can then be extrapolated by using these points. If information regarding color is gathered at every juncture, the determination of colors on subject's surface can be easily done. 3D scanners share analogy with cameras. If one tries to define a Spherical Coordinate System wherein the origin would be the scanner and vector would be drawn from front of it such that θ=0 and ¢=0, then every point in picture would be associated with θ and ¢. Combined with distance that corresponds to r component 3D position of every point in picture is described by the spherical coordinates.
Technology: 3D scanners consist of two types- non-contact and contact. Non-contact three-dimensional scanners could be divided further into 2 major categories- passive and active scanners.
Non-Contact Active: Some light or radiation is always emitted by active scanners. It is advised to detect the reflection of this light, as it would help in locating environment or an object. The kinds of emission possibly used include x-ray, ultrasound, or light.
Contact: Contact three-dimensional scanners locate the subject by the way of physical touch. The best example of contact three-dimensional scanner is a CMM (Coordinate Measuring Machine). It is widely used in manufacturing processes due to its precision. However, it has a disadvantage that contact with object to be scanned is required. The target object might get modified or damaged by scanning. Historical artifacts, in particular, have to be specially taken care of.
3D Prototyping: 3D prototyping is the subset of rapid prototyping. The basic advantage of 3D prototyping is that numerous materials can be used as base materials. It involves taking of virtual designs through CAD (computer-aided design) or Animation Modeling software, transforming them into virtual, thin, and horizontal cross sections, and then creating every cross-section in the physical space, 1 by 1 till the model gets completed.
It should be noted that STL File Format is the interface between machines and CAD software. This interface carries out the approximation of shape of an assembly or part by making use of triangular facets. Surfaces of a superior quality are produced by smaller facets. 3D prototyping is believed to be the ‘next level' equipment by most of the experts of this field. Pioneer companies are striving to master the technique. The conservative prototyping machines cost around 25000 pounds, as per the study conducted in the year 2005.
