Abstract: This invention provides a system and method for balanced-demodulation procedures that remove image clutter even in the presence of scene motion. A system that employs balanced demodulation moves a chopping reticle located in the intermediate focal plane where front end optics focus a high-resolution image. The chopping reticle has a checkerboard pattern of clear and opaque cells and moves in an uneven rate (e.g. ?x??y) along the x-axis and y-axis. The resulting image is projected on a focal plane array from which differences are calculated to generate the desired balanced demodulation value. This invention further provides a foveal enhancement of the baseline spatial-modulation staring sensor. In this enhancement the WFOV low-resolution conventional image is displayed to the operator, but with a selectable subarea of that image replaced by a conventionally generated high-resolution image at the same scale.

Abstract: A two color radiation detector. A dispersive lens with a spectrally selective central obscuration focuses a first radiation band on a central location on focal plane array. The dispersive lens also focuses an annulus of out of focus radiation of a second radiation band concentric with the central location on the focal plane array. For point target detection the dispersive lens transmits plume band and guard band radiation to the staring focal plane array sensor. The staring focal plane array is located at the focal point of the plume band radiation. A spatial filter detects target signatures using information from the plume band and guard band radiation.

Abstract: A lens-sphere optical system for use in a low resolution, very wide angle optical sensor system for viewing incident energy from a scene of interest. A lens-sphere forms an output image of the scene of interest on a spherical surface. Apparatus for optically filtering the lens-sphere blocks incident energy outside of a predetermined range of incident angles. Apparatus for detecting the optically filtered output image is provided.

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 passive range measurement device and method are described which utilizes a digitized image stream derived from images taken by a camera which is also part of the device. The device also includes a digital processor which operates on the image stream to extract the coefficients of an address modification function from which range to each point in the scene, relative camera-scene, and camera-platform orientations may be derived. The extraction process is based upon calculation of a vector field which describes the pixel-to-pixel misregistration between two images. Improvements in the modification function are found from global, then localized averages of the vector field. Thus, a topographic map of the scene which is referenced to the position of the camera and platform is created, and may be used to create a terrain following capability.

Abstract: An improvement to an electronic zoom system allows operation with a single vidicon camera and an electronic storage means to provide a viewer with zoom capability and a display that has effectively no loss of resolution.

Abstract: A zoom system is provided which utilizes wide angle and narrow angle vidicon cameras, a display and an electronic system under an operator's control which operates to blend and magnify signals from the cameras so as to provide the viewer with a zoom capability for the display without effective loss of resolution.