期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：2008
卷号：XXXVII Part B1
页码：331-336
出版社：Copernicus Publications
摘要：Laser footprint size and beam divergence angle tuning was found to affect LiDAR data accuracy and measurement precision because of beam axis shifting. The laser beam divergence angle is generally tunable in modern LiDAR systems in order to adapt to different application scenarios. Beam divergence angle can either be switched from one position to the other (i.e. 0.3mRad / 0.8 mRad), or be tuned continuously (i.e. 0.3 to 0.8 mRad). In either case, mechanical moving parts have to be introduced into the optical systems. As a result, the movements of mechanical parts make the optical axis shift and the laser pointing direction shift as well. In other words, switching laser beam divergence angle makes the laser pointing accuracy degrade. A mathematic model was developed to improve the LiDAR data accuracy when the laser beam divergence angle was changed in surveying practice. Experiments were designed and carried on to verify the calibration model. A calibration method and procedure was introduced to handle these issues
