Abstract: An imaging sensor for scanning a thermal image is disclosed. The imaging sensor comprises a first set of elemental detectors operable to receive a thermal image during a first portion of the calibration cycle. A second set of elemental detector is provided which are operable to receive the image during a second portion of the calibration cycle. Means are provided for calibrating the first and second sets of elemental detectors by comparing the output of the first set of elemental detectors during the first portion of the calibration cycle with the outputs of the second set of elemental detectors during the second portion of the calibration cycle.

Abstract: An imaging sensor for scanning an image in an object space is disclosed. The imaging sensor comprises a first and second plurality of infrared detectors. Also provided is a reflecting means for reflecting a predetermined portion of the object space on the first plurality of infrared detectors during first portion of the scanning cycle. The reflecting means is further able to reflect the predetermined portion of the object space on the second plurality of infrared detectors during the second portion of the scanning cycle. In a further embodiment, the orientation of the detectors permits each of the detectors to be calibrated with respect to another of the detectors by a sequential comparison of the outputs of pairs of the detectors whose fields-of-view overlap.

Abstract: An integrating transimpedance amplifier 10 comprises a differential amplifier constructed of GaAs, MESFET, HEMT, SDHT or MODFET transistors has an input coupled to the output of a radiation detector 12 and an output expressive of the detector signal integrated over a predetermined interval of time. The amplifier has a transistor Q0 coupled to the input for coupling the input periodically to a predetermined voltage potential and a transistor Q.sub.9 coupled to the output of the amplifier for simultaneously periodically coupling the output to a predetermined voltage reference, thereby initializing the amplifier at the beginning of an integration period. A buffer transistor Q.sub.4 couples the output of the amplifier to a GaAs MISFET switch Q.sub.8 which is periodically activated to couple the buffered amplifier output to a storage capacitor Csmp.

Abstract: A protective coating for solar cells, particularly solar cells positioned in space and which coating is a polyimide which is colorless, transparent, relatively non-brittle, has a high degree of thermal stability and readily transmits solar radiation without appreciable degradation. The coating is heat resistant and does not degrade significantly when exposed to ultraviolet radiation, and is highly effective in repelling low energy proton particles.

Abstract: A first embodiment includes a set of diffraction gratings on the face of a wheel, each grating being set at an angle to select a different spectral line. The wheel is rotated, and as each grating moves into the end-reflector position of the laser's optical path, the laser is fired. Alternate embodiments include a small spinning fold mirror that reflects the beam in a circle about the axis of the laser.

Abstract: Apparatus and method for preventing the escape of contaminates outgassing from polymer materials within an enclosure. In an illustrative embodiment the invention provides an exhaust path for an electronic enclosure 10 containing polymeric materials (12,14). The exhaust path comprises a tubular member 16 which permits the atmospheric gases within the enclosure to escape from the enclosure during liftoff. Within the member are at least one region 26 containing an ionizing source, such as a radioactive substance which emits alpha particles. These alpha particles are relatively low energy particles and are stopped by a relatively thin layer of material. The radiation polymerizes, into a solid surface film 30 outgassing molecular species 28 as they traverse the inner region of the member. The use of the invention provides for permitting the atmospheric gasses within the enclosure to escape the enclosure during the initial ascent and, further, serves as a pathway and removal device for molecular contaminates.

Abstract: A new group of silane compounds in which silicon atoms are linked together by a hydrocarbon chain and which comprise phenyl groups substituted with an epoxy group or an ethenyl group. The compounds of the present invention have the formula ##STR1## where R.sub.1 is selected from the group consisting of:(a) an aliphatic hydrocarbon group containing 2 to 10 carbon atoms, and(b) a group having the formula ##STR2## where n=1 to 3m=0 to 5;R.sub.2 and R.sub.2 ' are each selected from the group consisting of an alkyl group containing 1 to 4 carbon atoms, an unsubstituted aryl group, and a substituted aryl group;and R.sub.3 is selected from the group consisting of: ##STR3## where R.sub.4, R.sub.5, and R.sub.6 are each selected from the group consisting of H, an alkyl group containing 1 to 4 carbon atoms, and an aryl group; and n=0 to 10.

Abstract: A device-implemented method for driving a ferrimagnetic load (10), such as a phase shifter in an antenna array, which precisely meters the amount of magnetic flux imparted to the load (10) by sensing the voltage applied to a winding and integrating the sensed voltage over time. The time intergrated voltage is proportional to the magnetic flux imparted to the load (10) and is constantly compared to a preprogrammed value stored in a memory (18). When the sensed voltage reaches the preprogrammed value, the voltage is removed from the load (10) so that a metered amount of magnetic flux, proportional to the preprogrammed value, remains in the load (10). The load (10) is initially reset by delivering current in one direction through its winding until saturation is reached. The load (10) is set with a metered amount of magnetic flux by delivering current in the opposite direction through the winding.

Abstract: An optical coating which is stable upon sustained exposure to water vapor is provided by a low-temperature photochemical vapor deposition process. First, there are provided a first vapor phase reactant containing silicon, a second selected vapor phase reactant, and an oxygen-containing precursor which are capable of interacting upon radiation inducement to form the corresponding oxides of the vapor phase reactants. A chosen substrate is exposed to the first and second selected vapor phase reactants in predetermined proportions and the chosen oxygen-containing precursor in the presence of radiation of a predetermined wavelength to induce a reaction to form a coating on the substrate. The coating comprises silicon dioxides containing a predetermined proportion of the second oxide, such as lead oxide. The coating maintains stable optical properties upon sustained exposure to water vapor. Graded index optical elements as well as quarterwave stack structure may be formed by this process.

Abstract: A receiver is disclosed for acquiring and tracking a data signal in a highly stressed environment. The receiver comprises first and second I.F. sections, a mixer for translation from the first I.F. frequency to the second I.F. frequency, a 2 kHz bandpass filter at the second I.F. frequency, signal translator for synchronous translation of the signal at the second I.F. frequency to baseband, a digitizer for complex sampling operation on the baseband signal, a microprocessor for processing the digital samples, and a numerically controlled oscillator coupled to the mixer and controlled by the microprocessor. The microprocessor formulates matched digital discrete Fourier transform filters which drive frequency, phase and symbol lock loops at the symbol rate. Each of the loop filters is formed by symbol-rate recursive, first-order equations.

Abstract: An associative memory system incorporating a hologram, a spatial light modulator (SLM) and thresholding components in a feedback loop to derive an enhanced reference beam for use in reconstructing a stored image. In a preferred embodiment, the SLM includes a liquid crystal light valve (LCLV). A polarizing thresholding analyzer device provides adjustable thresholding. An enhanced thresholded reference beam thereby derived is sent back to the hologram for readout and the stored image is reconstructed at the output plane of the system. In an alternative embodiment, two spatial light modulators and two feedback loops are provided in a resonator configuration.

Abstract: Wire bonds are closely spaced about the edge of a semiconductor chip device (150) in an orthogonal array. Even though the wires may have a fan out pattern to their second bond locations, close spacing of the first bond pads is achieved by use of rectangular pads (154) having their long dimensions all perpendicular to the chip edge, making all of the first bonds along lines perpendicular to the chip edge and then bending the wire to extend to the second bond.

Abstract: Motors (42,44) each have a pinion driving ring gear (62). Motor (42) is mounted on the platform and motor (44) is mounted on ring gear carrier (56). Rotation of either motor rotates carrier (56), hubs (40) and shaft (30).

Abstract: A lightweight mirror comprises a silicon carbide (SiC) foam core having a bulk density of approximately five percent. The mirror further comprises two solid facesheets each of which is integrally formed upon a surface of the SiC foam core, the facesheets being comprised of SiC. Upon a machined surface of one or both of the facesheets a further layer of SiC is deposited to reinforce the SiC facesheet and to provide an optically polishable surface. This outer layer of SiC may be deposited by chemical vapor deposition (CVD) techniques. After depositing this reinforcing layer of SiC, the layer is machined and polished to provide a mirror surface having a desired flatness and optical quality.

Abstract: A method is disclosed for the strain-free mounting of a component, such as a mirror, in a manner that allows differential thermal expansion or contraction to take place without distortion of the component. The mounting method makes use of a linear bearing that is rigid in all directions except one. Such a linear bearing is used at two or more points of support on the circumference of a mounting circle or circles. Relative motion in the linear bearings occurs along a line which is an extension of a radius of the mounting circle. The linear bearings each contain two sets of opposed rolamite mechanisms moving in parallel directions in the perpendicular arms of a "Y"-shaped frame.

Abstract: An optical element (10) is bonded to a support (12) by a resilient bonding agent (20). The bonding agent has the property of shrinking upon curing. It is placed within a bonding space (18) defined by rails (14, 16). Upon curing, the bonding agent shrinks and securely pulls the element against top surfaces (14a, 16a) of the rails under tension of the bonding agent.

Abstract: A satellite communications system employs separate subsystems for providing broadcast and point-to-point two-way communications using the same assigned frequency band. The broadcast and point-to-point subsystems employ an integrated satellite antenna system which uses a common reflector (12). The point-to-point subsystem achieves increased communication capacity through the reuse of the assigned frequency band over multiple, contiguous zones (32, 34, 36, 38) covering the area of the earth to be serviced. Small aperture terminals in the zones are serviced by a plurality of high gain downlink fan beams (29) steered in the east-west direction by frequency address. A special beam-forming network (98) provides in conjunction with an array antenna (20) the multiple zone frequency address function. The satellite (10) employs a filter interconnection matrix (90) for connecting earth terminals in different zones in a manner which permits multiple reuse of the entire band of assigned frequencies.

Abstract: The MOS switch described herein includes first and second MOS devices serially connected in a common substrate. Each device includes source, drain and channel regions which are biased to conduction in series between input and output terminals of the switch in its "on" or conductive state. The novel device connection prevents any pn junction in either MOS device from becoming forward biased. This action, in turn, prevents any parasitic bipolar transistor action in either device after the MOS switch turns off. This latter operational feature eliminates the need for a fourth terminal through which a DC bias potential is applied to either MOS device, and thus undesirable shifts in threshold voltage produced by such DC bias are eliminated.

Abstract: Linearity and efficiency of a radio frequency multi-stage power amplification device 10 are increased by employing two tuned circuits 16 and 18 in the driver stage 12 and two tuned circuits 22 and 24 in the high power stage 14. After selecting elements of tuned circuits 22 and 24 in order to optimize the high power stage 14 for efficiency, linearity, and power output, elements are selected for tuned circuits 16 and 18 in order to cause the intermodulation output components associated with the driver state 12 to have a 180.degree. phase angle relative to the intermodulation output components associated with the high power stage 14. This phase angle relationship will cause the intermodulation output component products from the driver 12 and high power stages 14 to cancel.

Abstract: A phase lock loop for use in carrier acquisition employing a predetection filter and a loop filter switchable between a constant phase margin and second order characteristic. In the acquisition mode, the constant phase margin characteristic is employed to acquire the carrier and the second order characteristic is thereafter employed to track the carrier. The second order characteristic retains only the pole at the origin and the lowest frequency zero of the constant phase margin characteristic. The filter parameters are selected to minimize the mean square deviation of a phase margin expression which includes contributions from the predetection filter pole and from positive poles generated by the loop's voltage controlled oscillator. The loop filter is further provided with gain coefficients selected to maximize the probability of carrier acquistion at a plurality of frequencies and carrier to noise density ratios.