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Laser Scanning
Laser scanning is the controlled deflection of laser beams, visible or invisible. Scanned laser beams are used in some 3-D printers, in rapid prototyping, in machines for material processing, in laser engraving machines, in ophthalmological laser systems for the treatment of presbyopia, in confocal microscopy, in laser printers, in laser shows, in Laser TV, and in barcode scanners. Applications specific to mapping and 3D object reconstruction are known as '' 3D laser scanner''. Technology Scanning mirrors Most laser scanners use moveable mirrors to steer the laser beam. The steering of the beam can be ''one-dimensional'', as inside a laser printer, or ''two-dimensional'', as in a laser show system. Additionally, the mirrors can lead to a ''periodic'' motion - like the rotating ''polygon mirrror'' in a barcode scanner or so-called ''resonant galvanometer'' scanners - or to a ''freely addressable'' motion, as in servo-controlled galvanometer scanners. One also uses the terms ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deflection (physics)
In physics, deflection is a change in a moving object's velocity, hence its trajectory, as a consequence of contact (collision) with a surface or the influence of a non-contact force field. Examples of the former include a ball bouncing off the ground or a bat; examples of the latter include a beam of electrons used to produce a picture, or the relativistic bending of light due to gravity. Deflective efficiency An object's deflective efficiency can never equal or surpass 100%, for example: *a mirror will never reflect exactly the same amount of light cast upon it, though it may concentrate the light which is reflected into a narrower beam. *on hitting the ground, a ball previously in free-fall (meaning no force other than gravity acted upon it) will never bounce back up to the place where it first started to descend. This transfer of some energy into heat or other radiation is a consequence of the theory of thermodynamics, where, for every such interaction, some energy mus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
