| | The TopoSys systems are capable of measuring the signal strength of the laser pulse that is emitted and reflected by a target. One of the purposes served by the intensity measurement is to identify objects of identical height which are not distinguished in the elevation model. These are, for instance, traffic lane markings on roads. No differentiation can be made here in the elevation data, while the intensity data presents distinct measured values.
In the Falcon system, the measured intensity value is dependent on the reflectivity of the target at a wavelength of 1.5 µm and is recorded in the last echo. With the aid of the flight path information (position and altitude of the LIDAR system) each individual intensity measurement is time-synchronized with the associated distance measurements and converted into a gray-scale value with exact positional coordinates (point data). To obtain an image data format (e.g. Tif format), this point data is sorted into a regular raster.
The intensity data is generally supplied in geo-coded Tif format.
|
