Abstract: A gray code is produced from a minimum of gate logic by making available and monitoring master outputs of master-slave latch pairs, where the latch pairs are arranged to form a cascading chain of toggle flip-flop stages. The least significant bit through one less than the most significant bit in the gray code is supplied by the master latch outputs and the most significant gray code bit is supplied by the slave latch output of the last toggle stage in the chain.

Abstract: A pixel structure, which forms one element of a focal plane array, includes a bolometer having a detector and an insulator. The detector that is made from a material that absorbs incident thermal radiation and has an electrical resistance that varies in response to changes in the temperature of the material. The insulator has a plurality of serpentine legs disposed completely underneath the detector so that the insulator extends between the detector and the substrate. And the insulator supports the detector in a spaced-apart relationship with respect to the substrate to thermally isolate the detector from the substrate. To further improve the performance of the bolometer, the bolometer includes a resonant layer between the detector and the insulator. The resonant layer is disposed such that areas defined between the detector and the resonant layer, and between the resonant layer and the insulator, form first and second resonant cavities, respectively.

Abstract: The present invention provides a sealed-cavity miscrostructure and an associated method for manufacturing the microstructure. Specifically, the microstructure of the present invention includes first and second wafers that are positioned relative to one another so as to form a cavity between the wafers. The microstructure further includes a seal between the first and second wafers and surrounding the cavity to create a pressure seal for the cavity. This seal allows the cavity of the microstructure to be maintained at a predetermined pressure different from that of the atmosphere outside the cavity. Importantly, the microstructure of the present invention further includes a structrual bond between the first and second wafers that structurally intergrates the first and second wafers. The structural bond renders the microstructure more rugged such that the microstructure can withstand expansion, vibrational, and shock stresses experienced by the microstructure during subsequent manufacturing and use.

Abstract: A reference bolometer and the associated methods for fabricating a reference bolometer and for fabricating an array of bolometers are provided. The reference bolometer is fabricated such that a thermally conductive layer underlies the detector element, i.e., the absorber and transducer elements, and is encapsulated by a protective coating. The protective coating serves to prevent the thermally conductive layer underlying the detector element of the reference bolometer from being etched during the process of etching or otherwise removing other portions of the thermally conductive layer that underlie the detector elements of the imaging bolometers. As such, the thermally conductive layer of the reference bolometer maintains the desired thermal communication between the detector element and the substrate such that the output of the reference bolometer is unaffected by incident radiation.

Abstract: An optical filter system is described wherein a fluid, such as gaseous phases of water or carbon dioxide, is frozen onto a transmissive substrate positioned in the optical path of an infrared sensor system. The frozen material, which is preferably maintained at cryogenic temperatures, acts as a natural optical filter, absorbing certain undesirable wavelength bands of atmospheric infrared radiation, thus preventing them from reaching the detector of the sensor system. Simultaneously, the optical filter system allows certain desirable wavelength bands of infrared radiation to be transmitted, thus permitting them to reach the detector of the sensor system. The overall effect is to reduce the amount of noise and clutter generated by the undesirable atmospheric infrared radiation from reaching the detector of the sensor system, thus increasing the resolution and effectiveness of the sensor system.

Abstract: A system and method are provided for use with an uncooled infrared sensor. The system and method include a temperature compensated performance algorithm which is utilized to provide temperature compensated response and offset correction coefficients which are applied to a video signal of the infrared sensor to correct for variations in the video signal caused by temperature changes of the sensor.