This article was taken from the September 2011 issue of
Wired magazine. Be the first to read Wired's articles in print
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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.