Abstract: The system comprises a scanning telescope for scanning a field of view in a vertical direction. A detector array is positioned in the focal plane of the telescope for receiving radiant energy from the scanned image. The detector array comprises a plurality of elements which are positioned such that adjacent elements along the scan direction are offset with respect to each other. A processor receives output signals from each of the elements. The processor delays the signals received from leading elements in the array and adds these delayed signals to output signals from trailing elements in the array to form pseudodetector sums. Pseudodetector sums formed in this manner are geometrically filtered in a cross-scan direction and also filtered in the along scan direction.

Abstract: A focusing reflective mirror which is fabricated of a hoop structure having a reflective metalized membrane stretched over one face thereof and a metalized backing membrane over the opposite side forming a closed reflective structure. The contour of the flexible reflective surface is controlled by a differential pressure between the enclosed area behind the reflective surface and the ambient pressure. The particular configuration or contour of the reflective surface is controlled by a electropneumatic control system wherein a capacitive member is mounted behind the reflective surface and within the reflective structure which senses the distance between the capacitive member and the reflective surface and adjusts the focus by varying the relative pressure within the enclosed area behind the reflective member.

Abstract: A combination of elements for detecting leakage of electrically conductive fluids from tanks, including a reference electrode, an AC generator connected between the tank and the reference electrode, and one or more sensing electrodes positioned between the tank and the reference electrode. The storage tank and reference electrode are in contact with the ground. When the AC generator is energized, current flows in the circuit, and creates an electric field in the ground between the tank and the reference electrode. The sensing electrodes are positioned so that they are within the electric field when the AC generator is energized. An electric potential measuring device, such as a voltmeter, is used to measure the electric potential at the sensing electrodes relative to the tank. A significant change in the electric potential at any one or more of the sensing electrodes is an indication that a leak has occurred in the tank.