Laser scanning is a technique which can be used to gather data about an object or environment which can be used to create a 3D model or detailed reconstruction. There are a huge number of applications for laser scanning, ranging from the highly specialized laser scanning confocal microscopy used in scientific labs to the 3D scanning of objects of historical value which cannot be personally studied due to worries about damage, but can be studied in a reconstructed form with the assistance of a laser scanner. Several companies make laser scanners for various purposes.
Laser scanners can operate in several different ways, including a triangulation method and a “time of flight” method. In all cases, the laser is low powered, so that it will not damage the object being scanned, and a number of beams are shot at the object and recorded. Some objects scan better than others, with light objects tending to reflect more light, creating greater detail, and shiny objects causing refraction, which distorts the image. The data from a laser scanning session takes the form of a point cloud, a collection of tiny data points which can be used together to map an object.
The raw data from laser scanning can be run through a computer program which will use the point cloud to establish a 3D model. Because a laser scanner can only see what is visible, it is common to move the scanner around the object or to rotate the object during scanning to get a complete image of all sides and all angles. The computer program can stitch the data together, and information like color can also be added, if desired.
One use of laser scanning is in architecture and construction, where laser scanning can be used to model environments and landscapes, make 3D models of proposed structures, and in other activities. Laser scanning is also used to record objects so that they can be replicated, and to make copies of objects of historical value. The ability to laser scan an object and create a 3D model also allows museums to share their collections around the world without having to endanger the objects they are preserving; people can log onto a museum website, for example, and explore three dimensional models of objects of interest.
Laser scanning is also used in the entertainment industry, where scans can be performed to create computer models for digital effects. Forensic scientists may also utilize this technique to create models of crime scenes, and laser scanning can be used to make demonstrative evidence displays which are highly detailed.
By Mary McMahon
Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a All The Science researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.