Abstract: A scanning sensor system includes a light sensor and a scanning telescope having a first telescope subassembly and a second telescope subassembly. Each of the telescope subassemblies has a primary telescope mirror oriented to receive an incident light beam over an angular viewing range as the primary telescope mirror is rotated about a primary-mirror rotation axis, and at least one additional telescope mirror positioned to receive a reflected light beam from the primary telescope mirror. A primary mirror drive rotates the primary telescope mirrors about the primary-mirror rotation axis at a primary mirror angular instantaneous rate of rotation. A half-angle derotation mirror has a derotation-mirror axis parallel to the primary-mirror rotation axis. The half-angle derotation mirror is positioned to reflect light in the optical path when each primary telescope mirror is within the angular viewing range and to direct the reflected image along the optical path toward the sensor.

Abstract: A monolithic microelectronic array structure includes a microelectronic integrated circuit array having a first plurality of microelectronic integrated circuit elements each deposited on a front side of a substrate. The substrates are physically discontinuous so that each substrate comprises a substrate island which is physically separated from the other substrate islands. The monolithic microelectronic array structure optionally includes a first plurality of input/output elements with a respective input/output element associated with and directly connected to each of the microelectronic integrated circuit elements, and a second plurality of electrically conductive interconnects extending between the microelectronic integrated circuit elements of adjacent substrate islands. The monolithic microelectronic array structure may be planar, or it may be curved.

Abstract: A gun trunnion angular-sensing mechanism (30) is operable with a gun (20) mounted for elevational rotation on a gun trunnion (22). The angular-sensing mechanism (30) includes an angular-position readout device (32) having an input shaft (34), and a pinned parallelogram linkage (46) extending between the gun trunnion (22) and the input shaft (34) of the angular-position readout device (32). The linkage (46) rotates the input shaft (34) proportionately to a rotation of the gun trunnion (22), so that the angular position of the gun trunnion (22) may be sensed.

Abstract: A method and apparatus for protecting a bolometer antenna imaging array from out of band electromagnetic energy is disclosed. Protective pads are disposed upon a window in an optical system forming a millimeter wave image on an array of bolometer antenna sensors. The protective pads are effectively opaque to infrared and visible emissions and are aligned to shade the bolometer portion of the bolometer antennas from infrared and visible emissions, while leaving the antenna portion of each sensor in the array exposed to intercept the millimeter wave energy incident upon them.

Abstract: A silicon-based radiation-hard cryo-CMOS CCD process suitable for fabrication of devices (100) with sub-micron feature sizes. A re-oxidized nitride/oxide (RONO) layer (49″) is preserved in the CCD area (32) while plasma etching is used to define polysilicon 1 gates (50′) in the active FET area of the device. Thereafter, a wet chemical etching process, which does not destroy the integrity of the RONO layer (49″) in the CCD area, is carried out. A channel stop (48) is formed after the field oxidation step in the active FET area to reduce the space required for minimum diode breakdown voltage between the n+ source/drain region and the p+ channel stop.

Abstract: An electronic warfare system for detecting missiles which appear as points in an IR image. The system includes a point detect filter with two stages. The first stage produces a characteristic rabbit ear pattern in response to a pulse. The second stage produces a pulse in response to the rabbit ear pattern.

Abstract: A sensor/support system includes a sensor assembly having a planar radiation detector lying parallel to a reference plane, a readout circuit, and an interconnect joining the radiation detector to the readout circuit. The system further includes a support structure, the support structure having a platform with a first side to which the sensor assembly is affixed and a second side oppositely disposed from the first side. A shim is affixed to the second side of the platform. The shim is made of a shim material different from the detector material and the platform material. The shim reduces the strain in the interconnect when the temperature of the sensor/support system is changed, as compared with the strain in the interconnect in the absence of the stabilization structure.

Abstract: A two-color infrared warning device, having both wide-angle and narrow-angle search capabilities, and a directional countermeasure device are mounted on a gimbal pointing in the same direction. The warning device and gimbal are initially operated in a wide-angle, step-stare mode to search for threats. When a potential hostile target is found, the warning device changes to a narrow-angle mode to determine whether the potential target is hostile. When a hostile target is identified, the directional countermeasure device, which is pointed at the target by virtue of its mounting with the warning device on the gimbal, is activated.

Abstract: The system (10) includes a first mechanism (12) for receiving electromagnetic energy of a first wavelength from the scene (28) and providing electromagnetic energy of a second wavelength shorter than the first wavelength. A second mechanism (14) measures variations of the electromagnetic energy of the second wavelength over a predetermined area. The system is a millimeter wave imaging system (10). The first mechanism (12) includes a lens (12) having an index of refraction substantially greater than 1. The lens (12) is opaque to infrared electromagnetic energy and made of alumina, plastic, or other material having a relatively high index of refraction. The second mechanism (24) includes and array of bolometers (24) positioned parallel to an output aperture (24) of the lens and within a distance of the output aperture (24) that is much smaller than the second wavelength.

Abstract: A differential current mode amplifier circuit (5,5′) includes a first circuit leg having a first current source providing a current I1 coupled in series with a first transistor (m1) at a first circuit node (n1). The first transistor has a control terminal for coupling to an input signal potential (Vs). Vs is obtained from a unit cell of a radiation detector array, and is indicative of a magnitude of an integrated, photon-induced charge. The first circuit leg outputs a first output current (Is). A second circuit leg includes a second current source providing a current I2 coupled in series with a second transistor (m2) at a second circuit node (n2). The second transistor has a control terminal for coupling to an input reference potential (Vr). The second circuit leg outputs a second output current (Ir). A resistance (Rs) is coupled between the first circuit leg and the second circuit leg at the first circuit node and the second node.

Abstract: A radiation sensor. The inventive sensor has a two-level detector structure formed on a substrate in which a thermal detector element is suspended over the substrate as a microbridge structure. A receiver of electromagnetic radiation is provided on the same side of the substrate in a manner that efficiently couples the radiation field to the thermal detector element. The thermal detector element has a sandwich structure including a heater metal layer, a dielectric layer, and a thin film thermo-resistive material. The thermal detector element is suspended out of physical contact with the receiver. In one embodiment, the receiver is an antenna having a crossed bowtie configuration that efficiently couples the radiation field to the detector element. The inventive radiation sensors are especially useful for mm-wave and microwave sensing applications. The sensor can be used individually or in linear or two-dimensional arrays thereof.

Abstract: An integrated infrared and millimeter-wave monolithic focal plane sensor array having a substrate upon which an integrated array of infrared sensors and mm-wave sensors are provided at a first planar level on the same side of the substrate, and a planar antenna for receiving incident millimeter-wave radiation located at a second planar level located between the integrated array of sensors and the surface of the substrates for coupling the mm-wave radiation field to the mm-wave sensor. The antenna receiver of electromagnetic radiation, in one embodiment, is an antenna having a crossed bowtie configuration which efficiently couples the radiation field to the mm-wave sensor. The invention also is directed to a method of fabricating such a radiation sensor.

Abstract: An integrated dual sensor package comprises a housing, a first sensor assembly and a second sensor assembly. The housing includes an internal vacuum chamber, a first window and a second window. The first window is transparent to a first wavelength of propagating energy and the second window is transparent to a second wavelength of propagating energy. The first sensor assembly and the second sensor assembly each have an active region responsive to a respective one of the first wavelength and second wavelength of propagating energy. The first sensor assembly and the second sensor assembly are each mounted within the vacuum chamber with the active region of each of the first sensor assembly and the second sensor assembly adjacently aligned with a respective one of said first window and said second window. The common alignment structure also serves as a common thermal interface to the external environment.

Abstract: Variable shear A.C. interferometer based on a rotating radial grating. Light is passed through the rotating radial grating to produce multiple sidebands diffracted at various angles. These multiple sidebands produce overlapping (sheared) images of the input wavefront at a detector plane causing intensity variations proportional to the phase difference between the sheared wavefronts. An array of detectors is positioned to monitor the images on the detector plane and the outputs of each are processed to obtain the local slope of the wavefront averaged over each detector. From this data, complete wavefront slope information in one direction (X) can be obtained. By providing a second interferometer to make slope measurements in the Y direction, complete information can be obtained from which the entire input wavefront can be reconstructed.

Abstract: A method and circuit for controlling motors utilizing a multiple-phase sinusoidal signal generator (80) with control inputs (71,72,76) for determining motor (84) speed and direction. The multiphase sinewave generator has a synchronous-digital state machine (70) that provides a plurality of analog signals (1A-12A) having phase-shifted waveforms. A resistive-ring network (30) and instrumentation amplifiers (31) shapes the plurality of analog signals to provide a multiphase set of sinusoidal signals (77). Automatic-motor-control systems modify control-inputs (71,72,76) into the multiphase generator (80) based on feedback (105,86) to control motor (84) speed and direction.

Abstract: A method and related system provides an array of sensing elements located in rows and columns, and each column of sensing elements has a connected circuit chain which processes the signals from the sensing elements in that column. Each circuit chain produces a signal with a corrective gain value calculated for it relative to the datum of the array which is selected for the point where signal strength would be strongest. The method and device is capable of being used in a starring or scanning type array mode.

Abstract: A preloaded device includes a female component having a right-circular cylindrical internal surface and a first helical groove in the internal surface of the female component. A male component has a right-circular cylindrical external surface sized to be slidably received within the right-circular cylindrical internal surface of the female component, and a second helical groove in the external surface of the male component. The second helical groove has the same pitch as the first helical groove so that the second helical groove is in facing relationship along its length to the first helical groove when the male component is assembled to the female component. A spring component is received within the first helical groove and the facing second helical groove when the male component is assembled to the female component.

Abstract: An optical device is positioned to receive an image and to deflect it into spatially separate portions onto the mutually spaced photosensitive surfaces of an array of staring array detectors. The optical device, which can be implemented with prisms or mirrors, directs the deflected light portions only onto the photosensitive portions of the array, avoiding non-photosensitive gaps between the photodetectors. The focal surface of the optical device may be nonplanar, and in that case the photosensitive portions of the array are positioned to lie at the nonplanar focal surface. The portions of the image received by the individual photodetectors combine to form the overall image.

Abstract: A system and method of providing featureless covert communication is described. After synchronization is achieved between a covert transmitter and a covert receiver using two channels, one of which is a transmitted reference signal, a single channel is used to transmit the bulk of the communication message. The featureless covert communication system uses a digitally controlled noise source (capable of reproducing a pre-selected pseudo-random signal indistinguishable from ambient noise) at both transmitter and receiver. The digitally controlled noise source produces an uncorrupted reference signal at both locations. Since only once channel is used to transmit the message, 3 dB in power is saved. And, since the same reference signal is being generated locally at the receiver, corruption of the reference signal is eliminated, which improves the efficiency of the system by at least another 10 dB.

Abstract: A readout circuit (1) has an x-row by y-column array of readout unit cells (10) each having an input for coupling to an output of a radiation detector (16) and an output that is switchably coupled to one of y column output lines (21). Each unit cell includes a driver transistor (12) having a gate terminal coupled to the detector, a source terminal coupled to a source voltage, and a drain terminal switchably coupled to a drain voltage through one of y loads, such as one of y current sources (18). The drain terminal is switchably coupled to the one of y current sources through an output multiplexer switch (20). The current source is a common current source for all of the x unit cells coupled to a same one of the y column output lines. The unit cell further includes a capacitance coupled between the gate and drain terminals, and a reset switch also coupled between the gate and drain terminals.