I have had a request for an introduction to the basics of 3D laser scanning, or LIDAR. Their is a lot of information available on the web. For instance, from my last post, the USGS CLICK site is an excellent interactive resource. Another NOAA/NASA sponsored primer can be found here.
Briefly, LIDAR is the acronym for LIght Detetection and Ranging. Most of us are familiar with Radar, which stands for Radio Detection and Ranging. The principles are similar. In the case of LIDAR a laser pulse is reflected from a rotating mirror inside a laser scanner. The scanner itself can also rotate in some cases. By measuring the time delay between when the laser pulse is emitted, and when it returns to the scanner, the distance between the scanner and the object can be precisely determined. The scanner can also accurately measure angles.
When all of the distance, angular and positional information is processed the scanner can produce a highly accurate 3 dimensional data set, which is sometimes referred to as a point cloud. This active sensor approach enjoys many advantages over single point, passive optical surveying instruments and camera systems.
The platforms from which a LIDAR sensor can be used include satellite, aerial, tripod, handheld and the hottest technology appears to be mobile mapping. The applications range from atmospheric research to transportation surveys, from heritage preservation to automobile design, and from parts reengineering to offshore platform retrofits. The rock group Radiohead just used a scanner for graphics effects at one of their concerts.
Although the basic technology has been around since the 80’s, in many markets this disruptive technology is still in the early adopter stage. There is tremendous opportunity for companies to innovate in this market, and I hope to identify those as we move forward.