Abstract: Sensing in an elevated-temperature environment is provided using a sensor system having a sensor housing with an exterior wall with a window-support region having an outwardly facing external face, and a window through the window-support region of the exterior wall and affixed to the exterior wall. A sensor unit contained within the sensor housing receives an input signal through the window. A thermal-insulation layer is on the external face of the window-support region of the exterior wall at a location immediately adjacent to the window. The sensor system is operated in an environment wherein the window-support region of the exterior wall is heated to a temperature of greater than about 100° C. in the event that no thermal-insulation layer is present. In a typical application, the sensor system is attached to an aircraft such that the external face is in a forward-facing orientation, and the aircraft is operated such that the external face is heated by aerodynamic heating.

Abstract: A low power delta-sigma analog to digital converter 10 for converting current mode signals without an amplifier includes an integration capacitor 26, a comparator 30, and a first switch 24 in parallel with one another and coupled to an integration node 28. A FET 20 and the first switch are disposed in series between a dump capacitor 25 and the integration node. A second switch 27 operates to discharge the dump capacitor, and an output of the comparator controls both switches in opposition. Preferably, no op-amps are included in the circuit, and current is supplied by an imaging component 5. In a first comparator state, the first capacitor charges, the first switch is open and the second switch is closed, and the dump capacitor discharges. In a comparator second state, the first switch is closed and the second switch is open, and the integration capacitor transfers a fixed amount of charge into the dump capacitor through an injection FET operating in saturation.

Abstract: A motor drive system includes a motor having a rotary motor output shaft, a driven component, and a flexible coupling connecting the motor output shaft to the driven component. The flexible coupling is a helix formed of a first wound wire. The helix has a helix unbonded free length that is less than about two times a helix outer diameter. The approach is particularly suitable for miniature motors and their driven components, wherein the motor output shaft has a shaft diameter of less than about 3 millimeters and the helix outer diameter is less than about 3 millimeters.

Abstract: A lens assembly includes a housing having a housing body, a cylindrical bore in the housing body with an internal bore surface and a cylindrical housing axis, at least one access window through the housing body that permits external access to an interior of the housing body, and an interior helical recess in the bore surface. A cylindrical lens element has an external cylindrical lens element surface received within the cylindrical bore of the housing and a cylindrical lens-element axis coincident with the cylindrical housing axis. The lens element includes a lens positioned perpendicular to the cylindrical lens-element axis, an adjustment engagement that is externally accessible through the access window of the housing, and an exterior helical recess in the external cylindrical lens element surface. The exterior helical recess has the same pitch as the interior helical recess and is in facing relation to the interior helical recess.

Abstract: A sensor system for viewing the light energy of a scene has an imaging detector which converts incident light energy into an electrical signal. Two colors are separately imaged by the detector in two imaging regions. The imaging system for each color includes a color filter positioned between the scene and the respective region of the detector, an optical train that focuses filtered color scene energy, and an optical fiber bundle having an input end that receives the respective color scene energy from the optical train and an output end that directs the color scene energy onto the respective region of the detector using a nonlinear mapping. The optical fiber bundle is formed of a plurality of optical fibers wherein each of the optical fibers has an input shape and size at its input end and an output shape and size at its output end. The output shape and size are different from the input shape and size.

Abstract: An optical element is fabricated and inspected by forming a spherical-segment surface in a light-transparent blank at a first end thereof with a spherical-segment center on an element axis of the light-transparent blank. A trial parabolic surface is formed in a lateral surface of the light-transparent blank with a trial-surface parabolic focus coincident with the spherical segment center. The trial parabolic surface is inspected by directing a source light beam from a light source through the light-transparent blank parallel to the element axis and against the trial parabolic surface, whereupon a reflected light beam reflects back substantially parallel to the source light beam but oppositely directed to the source light beam. The reflected light beam is optically interfered with the source light beam to produce an interference pattern.

Abstract: An optical fiber system includes an optical fiber light transmission system having a light path therethrough, and a filter module positioned to controllably place light filters into the light path of the optical fiber light transmission system. The filter module includes a movable support on which light filters are mounted, and a drive mechanism operably connected to the movable support to controllably move the at least one light filter into and out of the light path. The drive mechanism is operated to move the light filters into or out of the light path.

Abstract: A leadscrew mechanical drive includes a leadscrew having a leadscrew axis and a leadscrew thread with a nonzero leadscrew thread pitch. A leadscrew follower structure preferably having two leadscrew followers is engaged to the leadscrew. Each leadscrew follower includes a threaded insert having an insert thread with a nonzero insert thread pitch different front the leadscrew thread pitch. The insert thread is engaged to the leadscrew thread over a circumferential distance of less than one-half turn of the insert thread. Each leadscrew follower further includes a bearing in which the threaded insert is received and which permits the threaded insert to rotate about an insert axis that is inclined to the leadscrew axis by an angle ? for the first leadscrew follower and ?? for the second leadscrew follower, and a bearing support in which the bearing is received. A preload structure biases each of the leadscrew followers against the leadscrew.

Abstract: Disclosed is a method for producing an array (20) of p-intrinsic-n light detectors, as is an array produced in accordance with the method. The method includes providing a wafer (1); forming a first layer (2) having a first type of electrical conductivity (e.g., n-type) over a surface of the wafer; forming a second layer (3) that is an intrinsic layer on the first layer and, for each light detector, implanting or diffusing a region (9A) into a surface of the second layer that is opposite the surface on the first layer, the region (9A) having a second type of electrical conductivity (e.g., p-type). The method further includes forming an opening or aperture, referred to herein as a V-groove (6), through the second layer at least to the first layer; and electrically contacting with a first electrical contact (15, 9B, 13B) the first layer through the V-groove.

Abstract: An optical multiplexing device includes a light bandpass filter that passes a first light wavelength at a first angle of incidence and passes a second light wavelength at a second angle of incidence. In a demultiplexing version, a light source directs a first incident beam including light of the first wavelength and light of the second wavelength at the first angle of incidence onto the light bandpass filter. The light bandpass filter passes the light of the first wavelength therethrough and reflects a first reflected beam therefrom. A first light receptor and redirector receives the first reflected beam and redirects the first reflected beam back onto the light bandpass filter at the second angle of incidence as a second incident beam. The light bandpass filter passes the light of the second wavelength therethrough and reflects a second reflected beam therefrom. The principle may be extended to the demultiplexing of additional wavelengths of light from the incident beam.

Abstract: A tool (10) for vacuum-holding an object, such as an integrated circuit die (20). The tool includes a body portion (16) having a vacuum outlet (16A) for being coupled to a vacuum source. The body portion is coupled to a plurality of tool leg portions (14A, 14B) each having an edge that defines a mating surface (15) for engaging an edge (20A, 20B) of the object. Each mating surface contains at least one vacuum inlet (12) in fluid communication with the vacuum outlet. In one preferred embodiment there are two leg portions providing two mating surfaces that meet at a corner, where the corner defines a 90 degree angle and corresponds to a corner of the integrated circuit die. A corner relief (15A) may be provided to ensure a good mating seal with the die edges. A gasket (18) can be provided to surround the at least one vacuum inlet for ensuring the quality of the vacuum seal.

Abstract: A leadscrew assembly has a wire-wound leadscrew driven by a mechanical drive. A preloaded leadscrew wire nut assembly serving as a leadscrew follower includes a first wire nut having at least one turn of a first-nut wire overlying and engaged to the groove between the turns of the thread wire, and a second wire nut having at least one turn of a second-nut wire overlying and engaged to the groove between the turns of the thread wire. The second wire nut is spaced apart from the first wire nut along a leadscrew axis. The leadscrew wire nut assembly further includes a compressed preload spring maintaining a compression preload against the second wire nut, and a wire-nut-assembly housing overlying the first wire nut, the second wire nut, and the preload spring. The wire-nut-assembly housing maintains the preload spring in compression.

Abstract: A unit cell (10) of a readout integrated circuit is constructed and operated so as to temporally align an image obtained in a first spectral band with a an image obtained in a second spectral band. A method operates, during a frame period, to sub-frame average a first signal detected in the first spectral band by a multi-spectral detector (12), to sub-frame average a first signal detected in the second spectral band by the multi-spectral detector, and to sub-frame average a second signal detected in the first spectral band by the multi-spectral detector. The method then reads out the sub-frame averaged signals for each spectral band. The sub-frame averaged may be read out simultaneously from the unit cell.

Abstract: A wafer structure is deposited on a composite substrate structure having at least two substrate layers bonded together. A first substrate layer is made of a first substrate material having a first-substrate-layer material transverse coefficient of thermal expansion, greater than the wafer transverse coefficient of thermal expansion, and a second substrate layer is made of a second substrate material having a second-substrate-layer material transverse coefficient of thermal expansion, measured parallel to the transverse direction, less than the wafer transverse coefficient of thermal expansion. The substrate layers are present in relative proportions such that the substrate transverse coefficient of thermal expansion differs from the wafer transverse coefficient of thermal expansion by not more than about 2×10?6/° F.

Abstract: Add/drop functions of light signals in an optical fiber light transmission system are performed using a group of bandpass light filters, wherein each of the group of bandpass light filters is operable to reflect a reflected wavelength band and transmit a transmitted wavelength band. A filter module is positioned to selectively place any of the group of bandpass light filters into a light path of the optical fiber light transmission system. A first add/drop function is accomplished by first positioning a first selected one of the bandpass light filters into the light path using a drive mechanism, directing the input light beam onto the first selected one of the bandpass light filters, performing the first add/drop function on the input light beam relative to a first band light signal in a first wavelength band, and removing the first selected one of the bandpass light filters from the light path using the drive mechanism.

Abstract: An optical zoom lens mechanism is arranged along an optical axis and produces a zooming effect by a transverse movement of transparent elements perpendicular to the optical axis. A first lens group has two adjacent, rotationally nonsymmetric transparent first optical lens plates that are each rotationally nonsymmetric relative to the optical axis, and a first-group drive is operable to move the first optical lens plates together and relative to each other in a first-movement radial direction relative to the optical axis. A second lens group has two adjacent, rotationally nonsymmetric transparent second optical lens plates that are each rotationally nonsymmetric relative to the optical axis, and a second-group drive is operable to move the second optical lens plates together and relative to each other in a second-movement radial direction relative to the optical axis.

Abstract: An NMOS field effect transistor (1) is made radiation hard by a pair of guard band implants (115) of limited horizontal extent, extending between the source (30A) and drain (30B) along the edge of the transistor body, and extending only to a limited extent into the field insulator and into the interior of the transistor, leaving an unimplanted area in the center of the body that retains the transistor design threshold voltage.

Abstract: An optical assembly includes an optical collimator having an outer periphery and an optical-path end opening. A collimator beam-path axis extends through the optical-path end opening. The optical assembly further includes a hollow bonding sleeve having a sidewall having an inner periphery receivable over and affixed to the outer periphery of the optical collimator, an endwall having an aperture therethrough in facing relation to the optical-path end opening of the optical collimator; and an optical device in registry with the aperture of the endwall and affixed to the endwall. To fabricate the optical assembly, the optical collimator and the bonding sleeve are separately prepared, the optical device is affixed in registry with the aperture of the endwall, the bonding sleeve is assembled to the optical collimator, the optical device is aligned with the collimator beam-path axis, and the bonding sleeve is affixed to the optical collimator.

Abstract: A mechanical actuator includes an annular electromagnet and a ferromagnetic plunger disposed within a bore of the electromagnet and slidable therein. A first permanent magnet is positioned outside of the bore and in facing relation to a first end face of the plunger, and a second permanent magnet is positioned outside of the bore and in facing relation to the second end face of the plunger. The plunger is slidable in the bore between a first position with the first end face adjacent to the first permanent magnet and a second position with the second end face adjacent to the second permanent magnet. Activation of the electromagnet with the current flowing in a first direction drives the plunger toward the first permanent magnet, where it is retained. Activation of the electromagnet with the current flowing in a second (opposite) direction drives the plunger away from the first permanent magnet and toward the second permanent magnet, where it is retained.

Abstract: A system and method for focusing infrared detectors operable at cryogenic temperatures. The invention includes a sensor (10) for detecting electromagnetic energy comprising a first detector (14) operable over a first temperature range and a predetermined number of auxiliary detectors (12) operable over a second temperature range, wherein the auxiliary detectors (12) are adjacent to and in the same optical plane as the first detector (14). In the illustrative embodiment, the energy is infrared or visible light, the first temperature range is a range of cryogenic temperatures, and the second temperature range is a range of ambient temperatures. The first detector (14) is a focal plane array and the auxiliary detectors (12) are uncooled detector arrays. In the preferred embodiment, the focal plane array (14) and the uncooled detectors (12) are disposed on a common substrate.