This article was taken from the September 2011 issue of Wired magazine. Be the first to read Wired's articles in print before they're posted online, and get your hands on loads of additional content by subscribing online.
LiDAR is mapping the world in precise three-dimensional detail from the air. Short for Light Detection and Ranging, LiDAR uses a laser beam to capture a digital 3D picture of a scene, such as this image of Wembley Stadium, London.
The Geomatics Group, based in Bath, provides airborne LiDAR and other remotely sensed data including photography, thermal imaging and hyperspectral imaging. A scanner mounted on an aircraft can capture objects as narrow as 25cm across -- the equivalent of one pixel in LiDAR's sensor -- and measure heights accurate to five centimetres. LiDAR works like a rangefinder, giving the exact distance to thousands of points within its field of view. Software calculates the three-dimensional co-ordinates of each point to create a "point cloud".
These 3D maps can be viewed from any point or angle, coloured to highlight contours and other features, or fused with photos or thermal images. Your move, Google Earth.
This article was originally published by WIRED UK
