The system of airborne lidar is equipped with a scanning mechanism which produces a swath of point clouds in each flight strip. The scanning is perpendicular to the direction of flight. The density of point clouds is one of the major quality measures for the data collected with airborne lidar. Point density, shade percentage, and penetration rate, are the major factors considered in the flight design. In practical operation, there are flight missions designed with 5% overlap ratio, as well as missions with 50%. Besides the overlap ratio, field of view is another important parameter of the flight design. An evaluation scheme to assess the overlap ratio between flight strips and the selection of field of view is proposed in this study.