Three dimensional imaging utilizing structured light

This paper describes a method of remote sensing the 3-dimensional structure of the proximity utilizing a laser, a holographic grating, and a single regular CCD camera. Basically, the laser beam is split by a holographic grating to form a regular spaced grid of laser beams that are projected into the field of view of a CCD camera. The laser source and the CCD camera are physically separated forming the base of a triangle. The exit angle of the laser beam and the angle measured by the camera where the beam intersects a surface is a function of the distance. These two angles and the distance between the source and the camera allow calculation of the range to the projected spot using triangulation. This paper describes an experimental proof of concept and an empirical calibration of the system. Encouraging results are achieved and presented. Also, an application in which this system potentially would be used for a Mars landing is discussed.