Abstract: A passive range measurement device and method are described which device includes a camera, onboard motion sensors, image digitizers and memories and a digital processor. The device creates a digitized image stream from successive images taken by the camera. The digital processor operates on the image stream in conjunction with information obtained from the onboard motion sensors to determine the location of a median plane through the scene, and the position of terrain detail located on that plane. By evaluating in like fashion hypothetical slices through the scene parallel to the median plane, a topographic range map of the scene may be created. This map is referenced to the position of the camera and platform, and may, therefore, be used to provide a terrain following capability.

Abstract: A system for determining whether an eye within a field of view is closed for a predetermined period of time and for distinguishing between reflections from an open eye and any specular reflections within the field of view. The system comprises detection apparatus for viewing the field of view. Also included is a first light source positioned so that light arising from the light source causes reflections from both an open eye and from any specular reflectors within the field of view to be detected by the detection apparatus. The system further includes a second light source positioned so that light arising from the light source causes reflections from the open eye to be directed so as not to be detected by the detection apparatus and so that light arising from the light source causes reflections from any specular reflectors in the field of view to be directed so as they are detected by the detection apparatus.