Selection of scanners for use in lidar systems

We compare the parameters for three types of scanners used in terrain-measurement lidar systems to facilitate spacecraft landing safety on extraterrestrial objects. The following 2D scanner designs are discussed: a rotating-wedge scanner with a straight-through optical path (Risley scanner), a scanner with a 12-sided line-scan prism, a frame deflector with a uniaxial oscillating mirror, and a scanner with an oscillating mirror mounted in a two-axis gimbal. We calculated the scan trajectories and estimated the required software-based object-plane beam corrections in the scanner-system deflector angle coordinates.