Note
Fixed and variable resolution video moiré techniques have been used to project structured illumination in a model undersea environment and a prototype system has been developed which generates equal depth contours of undersea objects and has applications in sizing, orientation and ranging. An advantage of this system is that the entire field is continuously illuminated, and the moiré contours and images are formed at video rates. The spatial frequency of the structured illumination can be continuously varied, providing optimal contours for a variety of object sizes. The data can be easily interpreted by eye or processed by computer to obtain surface shape, range and orientation of a known structure.