Abstract: Apparatus in a thermal radiation detection device including optics having a focal plane comprising a cold mounting surface, a detector array, a standoff and apparatus for protecting the detectors from intense thermal radiation. The detector array includes a plurality of radiation sensitive detectors mounted on a carrier in thermal contact with the cold mounting surface. The standoff defines a cold platform proximate to the detector array and mounted to the cold mounting surface. A substrate includes a film of vanadium trioxide on a first surface, wherein the substrate is mounted to the standoff at the first surface and wherein the substrate is structured and arranged to interpose the vanadium trioxide film between the detector array and a radiation source and is located proximate the focal plane.

Abstract: A shield for limiting the radiation received by an array of detectors along the length of the detector array of an electromagnetic radiation detection system to radiation provided to the detectors by the optics of the system. The shield comprises a pair of glass rods mounted in a parallel relationship to each other and to the linear direction of the array and forming an aperture along the length of the array so as to shield the elements of the array from electromagnetic radiation generated outside the field-of-view of the detectors.

Abstract: An improved prism cold shield for use in an infrared detection system which includes a detector array comprised of a plurality of detectors sensitive to a radiation of interest in a predetermined wavelength band. The prism comprises a substrate having a top surface partially coated with a first coating layer arranged to define a plurality of bow-like stripes alternating with top surface openings which are covered by a second coating layer. The substrate has a bottom surface partially coated with a third coating layer in a pattern to define a line of windows on the bottom surface which are aligned with the top surface openings so as to define a field of view for the plurality of detectors. The first and third coating layers ae comprised of high absorption, low reflectivity coatings in the wavelength band of the radiation of interest and the second coating layer is an anti-reflective coating.

Abstract: A prism cold shield adaptable to an infrared detector system comprising a prism-shaped substrate having an upper portion partially coated with opaque material and a lower portion partially coated with opaque material wherein windows formed by the upper and lower coatings defined the field of view for a plurality of infrared detectors thereby cold shielding the detectors in the linear direction of the detector array.

Abstract: A miniature, evacuated and hermetically sealed detector refrigerator assembly for use in infrared imaging systems incorporates a miniature Joule-Thomson laminar refrigerator which serves as the substrate for the detector subassembly, electrical leads, as well as the primary structural element of the assembly. The detector subassembly is positioned on the cold region of the refrigerator, surrounded by a vacuum chamber and capped by an optical window or filter as required. As a result, the detector is cooled in a small and relatively inexpensive package that can operate intermittently or continuously, as desired.

Abstract: A miniature, nonevacuated, detector refrigerator assembly for use in infrared imaging systems is described. The assembly incorporates a miniature Joule-Thomson laminar refrigerator which serves as the substrate for the detector subassembly, electrical leads, as well as the primary structural element of the assembly. The detector subassembly is positioned on the cold region of the refrigerator, surrounded by two prefabricated vacuum chambers and capped by an optical window or filter as required. As a result, the detector is easily built and is cooled in an efficient manner.

Abstract: A miniature, nonevacuated, detector refrigerator assembly for use in infrared imaging systems is described. The assembly incorporates a miniature Joule-Thomson laminar refrigerator which serves as the substrate for the detector subassembly, electrical leads, as well as the primary structural element of the assembly. The detector subassembly is positioned on the cold region of the refrigerator, surrounded by insulating material and capped by an optical window or filter as required. As a result, the detector is cooled while the contact pads used for connection to external devices are at the ambient temperature. A piece of high thermally conductive material may be placed in the vicinity of the detector subassembly so that during operation gases in the chamber surrounding the detector assembly will preferentially condense thereon rather than on the detector subassembly.

Abstract: A process for manufacturing spectral gratings having very low blaze angles by preferential etching of single crystal substrates with the resultant exposed crystal planes utilized as the grating.