Using Error Entropy to Evaluate Point Cloud Uncertainty Influenced by Spot

The spot influences the positional accuracy of terrestrial laser scanning. A Laser point in the spot is uncertain and the description of this uncertainty directly relates to the evaluation of positional accuracy. This paper introduces error entropy into the evaluation of point cloud uncertainty related to the spot. Point information entropy is deduced by using The probability density function of the laser point in the spot; and error entropy is obtained based on the relationship between error entropy and information entropy and evident in the relationship between error entropy and spot size; introducing average error entropy into the evaluation of point cloud uncertainty. The evaluation of average error entropy as a measure of point cloud accuracy influenced by laser spot was verified by an analysis of different scanning intervals, thus an evaluation of point cloud uncertainty influenced by the spot was realized.