Abstract: The invention is a focusing polarization rotator for use in the resonant mirror system of a ring laser gyroscope. The focusing polarization rotator accomplishes the traditional task of rotating the plane of polarization of a light beam that passes through it and at the same time performs a focusing function on the light rays. In a resonant mirror system, the device acts to constrain the transverse dimensions of light beams that follow the closed light-beam path established by the resonant mirror system thereby obviating the need for one or more curved mirrors that usually perform this function. The focusing polarization rotator is a wedge-shaped lens made from either a magneto-optic transparent material with a magnetic field within the lens or a material having different indices of refraction for left- and right-circularly-polarized light. The wedge shape of the lens greatly improves the bias stability of the RLG in which it is used.

Abstract: A night vision device (NVD) includes a control circuit having an acceleration-responsive switch. When the NVD is in a generally horizontal use position, the acceleration-responsive switch enables a circuit allowing voltage to be applied to an image intensifier tube of the night vision device, so that night vision is provided. On the other hand, when the device is flipped up to a stowed position allowing the user of the device unobstructed natural vision, the acceleration-responsive switch senses the changed orientation of the gravitational acceleration vector, and turns off the image intensifier tube as well as other light-emitting sources of the night vision device.

Abstract: An optical correlator system having a plurality of both active and passive reflective optical components between a source of electromagnetic radiation, such a visible coherent light, and an output detector array in a planar support body along a folded optical axis beam path within the body uses a ferro-electric liquid crystal spatial light modulator as the input sensor and the correlating filter to provide enhanced optical detection of an unknown object at a CCD detector array.

Abstract: The invention is a method and apparatus for generating a plurality of driving signals for a vibratory rotation sensor, the plurality of driving signals resulting in a plurality of readout signals from the vibratory rotation sensor. The method comprises the steps of determining a 2.times. tracking angle rate, transforming the 2.times. tracking angle rate into a trig function rate, transforming the trig function rate into a second trig function, and generating the plurality of driving signals utilizing the second trig function. The 2.times. tracking angle rate, determined from the plurality of readout signals, is the time rate of change of twice the tracking angle, the tracking angle being an angle which tracks the orientation angle of the standing-wave pattern of the vibratory rotation sensor. The trig function rate is the time rate of change of a first trig function, the first trig function being an approximation to a mathematically-exact (M-E) trig function.

Abstract: The invention comprises a mounting assembly for an optical sight. In accordance with one embodiment of the invention, a mounting assembly may comprise a first foot (552) and a second foot (556). The first foot (552) may include a top (563), a first side (570), and a second opposite side (574). The top (563) may have a first tab (566) sized to fit a first recess (568) of a sight (20). The first side (570) may engage a first edge (572) of a rail (562). A first clamp (554) may be coupled to second side (574) of the first foot (552) to engage in combination a second edge (576) of the rail (562). The second foot (556) may include a top (586), a first side (594), and a second opposite side (596). The top (586) may include a tab (590) sized to fit a second recess (592) of the sight (20) substantially normal to the first recess (568). The first side (594) may engage the first edge (572) of the rail (562).

Abstract: An integrated night vision device and laser range finder (10) provides night-time imaging of a scene by use of an image intensifier tube (14), as well as providing laser range finding operations. In a laser range finder mode of operation the device (10) projects a pulse of laser light into a scene being viewed, and a power supply and laser range finder circuit (50) of the device (10) temporarily utilizes the image intensifier tube (14) as a sensor to detect reflected laser light. During laser range finding, imaging is cut off for a very short time interval, and the image intensifier tube provides an electrical output signal in response to receipt of reflected laser light. A detection circuit (86, 86') associated with the image intensifier tube (10) receives the electrical output signal from the image intensifier tube (14), and includes a magnetic circuit. Oscillation in the magnetic circuit is effected by the electrical output signal of the image intensifier tube (14).

Abstract: The submount assembly includes a heat sink and a submount mounted upon the heat sink that is formed of a thermally conductive, electrically insulating material so as to transfer heat from the various components mounted upon the submount to the heat sink while effectively electrically isolating the various components mounted upon the submount. The first surface of the submount defines at least one registration feature, such as at least one recess, for precisely aligning components mounted thereupon. For example, the submount assembly can include a microresonator cavity including an active gain medium disposed within a respective recess defined by the submount. The submount assembly can also include a laser diode mounted upon the submount in alignment with the active gain medium such that the output of the laser diode pumps the active gain medium.

Abstract: The invention is a method for determining gravity in an inertial navigation system which periodically produces and stores in memory position coordinates. The method comprises the steps of (a) retrieving the most recently determined position coordinates, (b) determining coordinates L.sub.u, L.sub.n, H.sub.u, and H.sub.n from the position coordinates, L.sub.u and L.sub.n being predetermined functions of geodetic latitude and H.sub.u and H.sub.n being predetermined functions of geodetic altitude, (c) determining the vertical component of gravity by substituting either or both L.sub.u and H.sub.u in a first polynomial expression, (d) determining the north-south component of gravity by substituting either or both L.sub.n and H.sub.n in a second polynomial expression, and (e) utilizing the components of gravity determined in steps (c) and (d) in the next determination of the position coordinates.

Abstract: A fiber-optic acoustical sensor system includes a light source, an elongate optical cable conducting light from the light source to an optical acoustical transducer located at a distance from the light source along this cable, and a polarizer at the acoustical transducer. The sensor system includes a polarizer providing orthogonally-polarized light along the optical cable to the polarizer located adjacent to the transducer. Because of the polarizer adjacent to the transducer, disturbances of the optical cable and resulting polarization perturbations of the light transmitted along this cable do not affect the optical acoustical transducer. The acoustic transducer is responsive to sound energy to provide an optical return signal indicative of this sound energy.

Abstract: The invention is an apparatus for sensing rotation comprising a housing, a resonator attached to the housing, a first set of electrodes consisting of one or more electrically-connected electrodes, and a second set of N electrodes. The resonator is a rotationally-symmetric, thin-walled object capable of vibrating in at least one of a plurality of standing-wave modes. The orientation of a standing wave with respect to a reference point on the resonator is specified by an orientation angle. The first set of electrodes are attached to either the resonator or the housing. The N electrodes of the second set are attached around the circumference of either (1) the housing if the first set of electrodes is attached to the resonator or (2) the resonator if the first set of electrodes is attached to the housing. The n'th electrode of the second set is attached at angular position .theta..sub.n with respect to the reference point on the resonator, opposing one or more of the second set of electrodes.

Abstract: The uniformity of individual layers of multiple coating materials deposited on a substrate in a vacuum deposition process (such as for manufacturing mirrors for use in ring laser gyroscopes) is improved by an apparatus and method that include changing the masks placed in front of the substrate upon which the coating materials are to be deposited. Separate masks are tuned for each particular coating material to compensate for the unique plume shape of the material, and provide a uniform deposition of that particular coating material. Each mask is positioned in front of the substrate when the material for which the mask has been tuned is being deposited. The masks are changed when the coating material is changed, without venting the chamber.

Abstract: A plurality of heat-conducting compressible button contacts (10) between a heatsink (28) and an electronic part, e.g., a printed wiring board (22) or integrated circuit (24), to be cooled. A thin plate (16) and/or indentations (44, 44') in the heatsink are preferably used to support the heat-conducting buttons. Each heat-conducting button contact is placed in compression, generally, for example, by the heatsink. A thermal path is thus provided between the part and the heatsink. Differently sized compressible button contacts are used to accommodate disparate heights between the heat sink and surfaces on components of the electronic part.

Abstract: The invention comprises an alignment element for a multiple channel sight and method. In accordance with one embodiment of the invention, an alignment element (456) may comprise a first prism (492) and a second prism (494). The second prism (494) may be disposed proximate to the first prism (492). An adjustment device (506) may rotate the first prism (492) with respect to the second prism (494) to deviate an image of a first channel (54, 56) at an image plane (300).

Abstract: A night vision device (10) includes an improved fine-resolution microchannel plate (22) having a multitude of microchannels (32). The microchannels (32) are defined in groups (32a, 32b), with each group having plural microchannels. Each group of the microchannels originates with a single fiber pre-form (50) used in a process of manufacturing the microchannel plate (22). A method of making such a microchannel plate (22) is also explained.

Abstract: A system for measuring changes in an environmental parameter such as displacement, velocity, acceleration, or pressure, includes a laser for providing a pulsed, coherent light signal, and an interferometer having a first and second optical legs of unequal optical path lengths. The signal is split into first and second beams that are directed into the first and second optical legs. Either a fixed mirror disposed on a frame or a moving mirror on one side of the proof mass reflects the first beam received at the end of the first optical leg. The frame also suspends a proof mass at opposite ends. An optical pick-off embodied in a movable mirror formed on the proof mass reflects the second beam received from the end of the second optical leg. The proof mass with mirror moves in response to changes in the value of the parameter to be measured.

Abstract: A control device for molecular sieve on-board oxygen generating systems measures both temperature and pressure of the inlet air of an oxygen generating system. An electronic control unit applies pressure limits to a pressure measurement signal and combines it with a temperature measurement signal to produce a composite analog signal responsive to both temperature and pressure inlet air conditions. This analog signal is linearly converted to a frequency signal, whereupon the frequency signal is divided by a constant in order to produce a drive signal for control of the absorb/vent bed cycle valves. Composition control is achieved by venting product mixture as required. Inlet air pressures down to 5 PSIG (pounds per square inch gauge) produce correct system operation, and the quantity of conditioned air required is automatically limited so that system efficiency is higher than prior art systems.

Abstract: A system for manufacturing a photocathode includes a housing and a retainer disposed within the housing. The retainer includes a seating area operable to receive a first surface of the photocathode. The retainer is operable to independently translate relative to the housing along an axis. The system also includes a weight enclosed within the retainer. The weight is operable to provide a substantially uniform pressure across a second surface of the photocathode as the housing translates across a polishing pad substantially orthogonal to the axis.

Abstract: A laser marking system and an associated microlaser apparatus are provided which include a submount, a plurality of pump sources operably mounted upon the submount, and a microlaser disposed in alignment with the pump sources such that pump signals emitted by the pump sources pump respective portions of the active gain medium of the microlaser to produce a laser output. In order to impart a mark upon a workpiece that has a number of pixels, the laser marking system can be configured such that each pixel of the resulting mark is produced by the laser output generated by a different portion of the active gain medium of the microlaser in response to pumping by a respective one of the pump sources.

Abstract: A microchip laser assembly provides a microchip laser along with an integral Peltier thermoelectric temperature controller and temperature sensor. The temperature sensor measures the temperature of the microchip laser during operation so that the polarity and magnitude of a direct current to Peltier thermoelectric elements may be controlled, thereby controlling the temperature of the microchip laser and stabilizing the optical output frequency or other microchip laser operating parameters. The microchip laser assembly can be mounted, along with a pump source, upon a submount such that the microchip laser can be optically pumped. As a result of the construction of the microchip laser assembly, the temperature of the microchip laser can be controlled independent of the temperature of the pump source.

Abstract: A potting compound for use in the fabrication of fiber optic gyro sensor coils utilizes a silver-filled silicone base to reduce gyro sensitivity to changes in heat rate and thereby improve gyro performance during warm-up and periods of thermal cycling.