Abstract: An endoprosthesis cover may be attached to the distal end of a delivery device. The cover may be generally cylindrical in shape and may have a lumen through it. An endoprosthesis may then be covered as it is delivered to a treatment site.

Abstract: A modular laser gyro incorporating a laser gyro with a digital control processor. The digital control processor safely and quickly starts the laser gyro. The microprocessor also executes tests on the gyro and provides a health signal. Optional start-up operations may be performed including the calibration of volts per mode and system configuration. Various information including gyro parameter load commands, gyro control commands, gyro status commands, and gyro calibration and diagnostic commands may be provided to an inertial navigation system. A high voltage start circuit includes a high voltage start module and high voltage pulse generator apparatus. The high voltage start circuit is contained within a modular laser gyro housing. A direct digital dither drive for a dither motor controls the dithering of the gyro to prevent lock in of the laser beams. A dither stripper controls the stripping of the dither signal.

Abstract: A voltage source supplies power to a ring laser gyro and includes a pulse width modulator that charges an output capacitor network. An apparatus connected to the pulse width modulator assumes control so that the pulse width modulator continues to produce output pulses despite exposure to radiation.

Abstract: A sensor mount for mounting a sensor to a substrate having a support member, a substrate attachment surface, and a sensor attachment surface. The support member can be attached to the substrate at the substrate attachment surface and the sensor can be attached to the support member at the sensor attachment surface. The sensor mount is shaped so an oblique angle is formed between the plane that includes the substrate attachment surface and the plane that includes the sensor attachment surfaces. Preferably, the support member has a wedge shape.

Abstract: A circuit for controlling the run current in a ring laser gyro includes circuitry for sensing temperature, supplying a current to the ring laser gyro and controlling the current supplied to the ring laser gyro and the current varies depending on the temperature. The current changes at predetermined temperature points.

Abstract: A system for determining accurate inertial navigation data of a vehicle while moving must compensate for the orientation differences between an upper body and a lower body of the vehicle. These orientation differences are used to increase the accuracy of the aided inertial navigation solution.

Abstract: An optical header for coupling a light source to an optical fiber is disclosed. The header preferably includes a ceramic substrate that has a recess for a vertical cavity surface emitting laser (VCSEL), or alternatively an edge emitting laser. An optical fiber is preferably attached to a ceramic substrate and terminates at a light source. The end of the fiber is preferably cleaved or polished to an angle such that light entering the fiber from the light source is substantially reflected into the fiber. A reflective coating is placed on the cleaved end of the fiber thereby permitting a small percentage of light to radiate away from the fiber and toward an intensity detector. The light preferably travels to the detector through a transmission medium such as a prism or an optical-grade epoxy. The header is particularly useful when used in conjunction with multiple fibers simultaneously to form an optical fiber array.

Abstract: A method for forming an electrode seal between an excitation electrode and a laser block in a ring laser gyro having increased bond durability, strength, and greater resistance to solvents and reactive compounds. A thin ring of sealing material is positioned between an excitation electrode and a laser block of the ring laser gyro, and the sealing material is compressed. Chemical and physical bonds are formed between the excitation electrode and the sealing material and between the sealing material and the laser block. A pre-determined electrical potential is applied across the excitation electrode, the sealing material, and the laser block for a pre-determined period of time and at a pre-determined temperature. The electrical potential increases the number of chemical and physical bonds that are formed at the seal, thus increasing the bond durability and strength.

Abstract: An interferometric fiber optic gyroscope having compensation electronics to virtually eliminate rotation rate sensing errors caused by Kerr effect in the IFOG due to differing intensities of the counter-propagating beams relative to each other. Compensation accounts for varying intensities of the beams due to all or some changes of: the light beam splitter ratio relative to temperature; fiber coil loss due to temperature and longevity; and the intensity of the light source because of age.

Abstract: A method for fabricating a fiberoptic gyroscope and the fiberoptic gyroscope produced thereby are disclosed. The method and apparatus are characterized in that optical coils are connected to a substantially rigid member through flexible connectors, thereby enabling a modular unit with increased mobility and accessibility. Multiple assemblies may be arranged to enable the formation of multi-axis fiberoptic rotation rate sensors.

Abstract: Aircraft position determination system includes a transmitter to transmit a signal, and two receivers to receive the transmitted signal reflected from the terrain below the aircraft, and a phase comparison apparatus operating from the two receiver's inputs. A processor determines position based on the output from the phase comparison apparatus.

Abstract: An apparatus and method for prevention of migration of mobile ions in a gyroscope. A dielectric barrier material layer is placed between a gyroscope body and one or more gyroscope components. The dielectric barrier material layer reduces the electric field formed in the gyroscope block, and thus reduces ion migration therein. The material may prevent mobile ions from reaching the cathode seal.

Abstract: An error reducer for reducing rotation rate backscattering errors in a rotation sensor by adjusting amplitudes of bias phase modulators introduced phase changes or amplitudes of a backscatter phase modulator introduced phase change and bias phase modulator introduced phase changes.

Abstract: A head mounted display in which ambient light is used to illuminate a display to at or near the brightness of the scene being viewed when both reach the user's eyes. A small supplemental light source may further be used to increase the range of operation of the display when ambient light levels are insufficient to make the display screen viewable.

Abstract: A fiber optic gyroscope that includes an improved winding transition section otherwise known as a "jog zone". The improved jog zone reduces losses due to micro-bends and cross-coupling in the fiber optic coil. The reduced losses enable a more accurate measurement of rotation rate of the fiber optic coil, while minimizing unwanted phase-shifts that can cause false readings in the fiber optic gyroscope.

Abstract: The present invention provides a covert radar system in which radar signals emitted are capable to search receiver thermal noise and, therefore, are substantially undetectable in the normal radar operating range.

Abstract: A signal processing circuit for a fiber optic gyroscope which prevents glitches from saturating the photodetector and gain stages of the detection electronics by inserting random noise in the detected signal is disclosed. This technique allows one to control the noise density function, the noise level and the noise spectrum of the detected signal.

Abstract: A deadband error reducer for a fiber optic gyroscope, which is an offset modulation signal that averages the deadband producing error over the range of the feedback modulation signal provided to the phase modulator. Although the offset modulation signal may be introduced at any of several points in the feedback loop, the offset modulation must approximate a critical amplitude at the phase modulator. If the offset modulation is a signal having segments that are linear with time, the critical amplitude of this signal will be 2.pi..

Abstract: A structure and method of making resistive emitting members which exhibit high resistivity while at the same time providing high temperature operation significantly above that known in the art. Specifically the use of nitrides of Group IVB transition metals from the periodic table, exclusive of titanium is described.

Abstract: Disclosed is a mirror mounting device and method for beam path alignment of an optical cavity for a ring laser gyroscope. The ring laser gyroscope is of the type that includes a block having an optical cavity that defines a closed loop optical path. A light source directs a light beam into the path. The block includes mounting surfaces for mirrors that reflect the light beam at the optical path corners. The mirror mounting device is associated with one of the block mounting surfaces and acts to orient a concave reflective surface of one of the mirrors such that the light beam is aligned within the closed loop optical path and is at its maximum intensity irrespective of the position of the concave reflective surface of the mirror relative to its mounting surface.