Passive optical surveillance device - has azimuth and elevation scanning, with multi-detector at image plane

摘要

The main objective lens of the surveillance device collects the incident ray onto a canted mirror which rotates about a vertical axis with a speed of revolution half that of the azimuth scanning speed. By the corresponding choice of the direction of rotation, an image rotation is produced, which exactly compensates the tumbling of the image. The reflected beam is again diverted by a mirror in such a way that the new beam of light rays, coincides with the vertical axis of rotation, and then goes through a polygonal prism which produces the elevation scanning. A multi-element detector is situated behind the image plane. (DS).