Abstract: An infrared video camera system having a plurality of interchangeable imaging lens units and optical filter units. Identifying information, used to modify the operation of the camera system based on the specific imaging lens unit and optical filter unit attached thereto, is stored in an Electrically Programmable Read Only Memory (EPROM) located in each imaging lens unit and optical filter unit.

Abstract: A method for forming a mating piston and cylinder sleeve wherein the piston includes an outer diameter and a cylinder sleeve includes a bore for receiving the piston therein and wherein the piston outer diameter and the bore each form bearing surfaces having a gas film maintained in a gap therebetween. The method includes the steps of coating the piston outer diameter with a layer of PTFE based composite material and then diamond turning the piston outer diameter to a final piston diameter. The cylinder wall is also coated with a PTFE based composite layer which may be deposited by an electroless nickel plating process. The cylinder longitudinal bore is then diamond turned to a cylinder final diameter for mating with the piston final diameter.

Abstract: An infrared video camera system comprises an uncooled infrared sensor mounted and a thermally conductive thin walled radiation shield for shielding radiation from reaching an active surface of the uncooled infrared sensor. A TEC maintains the sensor active surface and the radiation shield at a substantially constant temperature. The uncooled infrared sensor and radiation shield are further housed in a hollow thermally conductive vacuum cover which is vacuum sealed with a base assembly and includes a vacuum sealed infrared transparent window in an aperture at a top end of the vacuum cover for allowing infrared radiation to reach the active surface and for forming a vacuum chamber enclosing the infrared sensor and radiation shield. A relay optical cell mounted to a camera body comprises at least one optical element for relaying an image formed at its entrance onto the active surface.

Abstract: An improved integral cryogenic refrigerator, or cryocooler, for cooling an electronic device to cryogenic temperature includes a regenerator sleeve having a cylindrical base portion and an integrally formed cold well tube. The cold well tube includes a thin outer wall and a longitudinal bore passing therethrough for providing an expansion cylinder for receiving a pressurized refrigeration gas therein. An outer surface of the thin outer wall of the cold well tube has an outer diameter substantially centered with respect to the longitudinal bore thereby providing a circular cross-section to the thin outer wall. At least one facet is formed onto the outer diameter by removing material from the outer diameter to reduce the thickness of the thin outer wall in the region of the facet thereby reducing the cross-sectional area of the outer wall.

Abstract: An infrared imaging system including a fixed magnification telescope, a two-axis variable angle scanner, a plurality of differently-sized infrared detectors positioned in the focal plane of the scanner, a selector to choose an output signal provided by one of the detectors, and a raster scan display. A single detector is associated with a particular desired field of view, with the size of the detector chosen to provide the desired resolution. To decrease the field of view encompassed by the imaging system, and thereby magnify the scene presented on the display, a smaller scan angle and a smaller detector are simultaneously selected. A gain and bandwidth normalization circuit is optionally used to normalize the electrical signals output by the various detectors. This arrangement allows reducing the field of view with a simultaneous change in the instantaneous field of view, so that resolution of a picture in the display accordingly increases.

Abstract: An integral cryogenic refrigerator, or cryocooler, for cooling an electronic device to cryogenic temperature. The cryocooler has a minimum number of moving parts. A lightweight flexure links a compressor piston to a coupler which is also connected to a regenerator via a lightweight vane. An electric motor with an offset shaft drives the coupler via a bearing through a circular path to impart properly timed motion to the compressor piston and regenerator. This arrangement minimizes the weight and number of moving parts, resulting in maximum efficiency and operating life. Vibration transmission is minimized by mounting the device to be cooled on an end cap having a raised castlated rim. A reusable access port allows the cryocooler to be readily recharged.

Abstract: A scan converter circuit for use in a imaging system that uses a sinusoidally oscillating scanning reflector for scanning an object and a constant rate scanned display monitor for displaying an image of the object. The circuit enables a variable time rate of sampling of picture elements in the object field to match a desired constant display rate of picture elements in the CRT display monitor. The circuit comprises a constant rate VCO clock and a sampling clock that produces periodically variable rate pulses, the periodicity of which being phase locked with zero crossings of the oscillating reflector and wherein the pulses are derived from the constant rate VCO clock. The sampling clock enables an image sensor to sample the radiance levels at a rate which varies with the sinusoidal sweep speed of the oscillating reflector.

Abstract: An image forming scanning mechanism without obturation in its optical path comprises first and second reflectors that are pivotally actuated about respective orthogonal axes. The scanning reflectors are positioned so that radiant energy in a first optical path from an object field impinges upon a vertical-scan reflector where it is directed to a horizontal-scan reflector and whereupon it is directed back onto the vertical-scan reflector from whence it is reflected along a second optical path in a different plane from the first optical path. The pivotal axes of the vertical-scan reflector and the horizontal-scan reflector are perpendicular to path of radiant energy reflected therefrom. A detector is positioned to receive radiant energy from elemental areas of an object field. The orthogonal disposition of the first and second pivotal axes provides a distortion free image signal from the detector that is comparable with the x-y scan pattern of conventional television display circuits.