A 3-D scanner represents an object as a 3-D image.
A 3-D scanner, as its name suggests, is a scanning technology that allows an object to appear as a 3-D (three-dimensional) object. The process involves creating a series of curves that define the physical geometry/layout and the surface characteristics of the object. This data is then represented using specialized computer software, which renders and blends the captured surfaces to add texture, shadows, reflections, color and other effects to show realism. Three-dimensional scanners are commonly used in aerospace, automotive, manufacturing and design industries.
Contact Scanners
Contact scanners, also called mechanical tracking systems, touch an object with a manual or automatic probe to make physical contact. The probe, as it moves over the object, records positional data in the form of points. This points are then converted to profile curves. Contact scanners have some disadvantages: they are liable to damage the object being scanned due to constant contact with it, and their scanning speed is slow in comparison with other types of 3-D scanning systems.
Laser Noncontact Scanners
Laser noncontact scanners commonly use a technique called triangulation to define and create 3-D objects. Through triangulation, these scanners scan objects by creating a laser stripe profile of an object or by directing beams of laser light at various points over the object to create a profile curve. These stripes or beams are sent back to a video camera or sensors that mathematically process the data by scanning the surface of the image from various angles and planes to generate the 3-D result. Laser noncontact scanners are portable, weatherproof, accurate and designed to work in a variety of indoor and outdoor environments. They are, however, associated with certain limitations: laser scanners are expensive and can only capture objects that lie within their field of sight. They must be set up multiple times to scan and record an object from various positions and angles for a precise depiction.
Ultrasonic Scanners
Ultrasonic scanners are noncontact scanners that create 3-D images by bouncing sound waves off an object and generating, or triangulating, the result in 3-D. Ultrasonic scanners have severe limitations: they are large, heavy machines that require effort in setting up; they are noisy; and the resultant image lacks detail and accuracy.
Magnetic Scanners
Magnetic scanners are similar in operation to ultrasonic scanners, with the only difference being that they generate magnetic fields, instead of sound waves, that bounce off objects. The triangulated points are digitized and converted into 3-D images. Magnetic scanners cannot scan objects with metallic parts---a severe limitation.
Tags: noncontact scanners, Contact scanners, from various, over object, scan objects, scanners commonly
