G01P 15/097 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration by making use of inertia forces with conversion into electric or magnetic values by vibratory elements
G01P 15/08 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration by making use of inertia forces with conversion into electric or magnetic values
G01P 15/09 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration by making use of inertia forces with conversion into electric or magnetic values by piezoelectric pick-up
G01P 15/18 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration in two or more dimensions
G01P 21/00 - Testing or calibrating of apparatus or devices covered by the other groups of this subclass
2.
Resonantly vibrating accelerometer driven in multiple vibrational modes
G01P 15/18 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration in two or more dimensions
G01P 15/08 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration by making use of inertia forces with conversion into electric or magnetic values
G01P 15/09 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration by making use of inertia forces with conversion into electric or magnetic values by piezoelectric pick-up
G01P 15/097 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration by making use of inertia forces with conversion into electric or magnetic values by vibratory elements
G01P 21/00 - Testing or calibrating of apparatus or devices covered by the other groups of this subclass
3.
Self-compensating resonantly vibrating accelerometer driven in multiple vibrational modes
G01P 15/097 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration by making use of inertia forces with conversion into electric or magnetic values by vibratory elements
G01P 15/08 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration by making use of inertia forces with conversion into electric or magnetic values
G01P 15/09 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration by making use of inertia forces with conversion into electric or magnetic values by piezoelectric pick-up
G01P 15/18 - Measuring accelerationMeasuring decelerationMeasuring shock, i.e. sudden change of acceleration in two or more dimensions
G01P 21/00 - Testing or calibrating of apparatus or devices covered by the other groups of this subclass
4.
Multi-axis fiber optic gyroscope photonic integrated circuit for inertial measurement units and inertial navigation systems
A photonic integrated circuit (PIC) comprises at least two optical circuits disposed on the PIC, two or more optical interfaces each configured to provide a connection to at least one external optical component, and a layout arrangement of the at least two optical circuits on the PIC, the layout arrangement configured such that the two or more optical interfaces are situated in at least one local group of optical interfaces, and the at least one local group of optical interfaces is located on at least one facet of the PIC. The at least two optical circuits may comprise a set of N single-axis 2×2 optical fiber optic gyroscope (FOG) circuits for use as a multi-axis FOG assembly in an inertial management unit (IMU) or an inertial navigation system (INS).
G01C 19/72 - Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams with counter-rotating light beams in a passive ring, e.g. fibre laser gyrometers
A low propagation loss and loose fabrication tolerance waveguide for a photonic integrated circuit (PIC) device may be realized by using a weak optical confinement to the optical mode, through designing a waveguide of single or double thin strips with high aspect ratio as waveguide core. To introduce a modulation functionality on this type of PIC device, a thin-film electrooptic material may be incorporated to form a hybrid phase modulating device, where a material that can be processed easily may be used as a device layer and is bonded to, or deposited with, a thin electrooptic film that may otherwise be difficult to fabricate or process. A low insertion loss, compact size and high-efficiency phase modulator on PIC device with this type of weakly confined waveguide is disclosed.
G02F 1/225 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour by interference in an optical waveguide structure
G02F 1/025 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour based on semiconductor elements having potential barriers, e.g. having a PN or PIN junction in an optical waveguide structure
8.
Integrated optical polarizer and method of making same
An integrated optical polarizer for generating linear polarizing light may be formed in a photonic integrated circuit (PIC) for applications that require stable output state of polarization. The integrated polarizer may be built by using the same materials already present in the PIC without use of other additional layers and claddings, and without other additional structural modification to the waveguide profile. The integrated polarizer comprises a plurality of bending waveguides of a pre-determined radius that are connected to each other in sequence. The bending waveguide has a high birefringence and a loose confinement to conduct one polarization mode and attenuate the other polarization mode. The polarization discrimination is controlled with the degree of the mode confinement, the bending radius, and the number of the bending waveguides that are connected in series.
G02B 6/126 - Light guidesStructural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind using polarisation effects
G02B 6/12 - Light guidesStructural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
9.
Method and apparatus for control and suppression of stray light in a photonic integrated circuit
In a photonic integrate circuit (PIC) architecture, non-guided stray light that is radiated from components, junctions, discontinuous and scattering points in an integrated optic device, may be received by an integrated waveguide structure in the path of the stray radiation. The integrated waveguide structure may comprise a plurality of collectors that are configured to collect the non-guided stray light from the radiating source. Each of the collectors may comprise an integrated waveguide with a front end that is tapered to increase the mode-field size and pointed toward the stray light source, and with a back end that is connected to a secondary waveguide. The collectors are placed in the path of the stray light and aligned in the propagation direction of the stray light. The collected stray light is guided to a light energy damper through the second waveguide for converting light energy into heat.
G02B 6/122 - Basic optical elements, e.g. light-guiding paths
G01C 19/58 - Turn-sensitive devices without moving masses
G02B 6/12 - Light guidesStructural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
H01L 31/12 - SEMICONDUCTOR DEVICES NOT COVERED BY CLASS - Details thereof structurally associated with, e.g. formed in or on a common substrate with, one or more electric light sources, e.g. electroluminescent light sources, and electrically or optically coupled thereto
10.
Polarizer implemented in a photonic integrated circuit for use in a fiber optic gyroscope
A multifunctional photonic integrated circuit (PIC) suitable for the manufacture of fiber optic gyroscopes (FOG) is described. The PIC is constructed and arranged to exhibit a scale factor of substantially high stability and accuracy. The PIC may comprise, for example, a high optical birefringence and low propagation loss waveguide, a low wavelength-dependent split-ratio Y-junction, a high extinction ratio linear polarizer, and high efficiency fiber-to-waveguide mode-size converters. Considerations for ensuring high-level FOG performance are addressed by, for example, optimization of waveguide structure, functional requirements for individual components, and combined effects of the circuit layout. A high-end, tactical grade FOG may be built using the disclosed PIC, after connecting to polarization maintaining optical fiber coil, a light source, and a photodetector.
G01C 19/72 - Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams with counter-rotating light beams in a passive ring, e.g. fibre laser gyrometers
G02B 6/293 - Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
G02B 6/42 - Coupling light guides with opto-electronic elements
11.
Global navigation satellite system (GNSS) spoofing detection and mitigation
A method of detecting and mitigating Global Navigation Satellite System (GNSS) spoofing events may comprise determining a first vehicle state based on an Inertial Navigation System (INS) without GNSS input, determining a second vehicle state based on an INS with GNSS input, and comparing the first vehicle states. When a difference between the vehicle states exceeds a predetermined threshold, the method concludes that GNSS spoofing is present, and utilizes only the first vehicle state as a correct vehicle state. The method may further implement at least one state processing path, comprising consecutive processing runs based on INS sensors. The method may further comprise reevaluating the vehicle state processing path, when the difference between the first vehicle state and the second vehicle state exceeds a threshold, to extricate a GNSS component from the processing path to at least a predetermined amount of time prior to when the GNSS spoofing was detected.
G01S 19/49 - Determining position by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system whereby the further system is an inertial position system, e.g. loosely-coupled
A semiconductor laser source includes a partial-grating DFB laser with two laser electrodes, one over the grating and the other between the grating and one end of the laser. Constant laser currents flow into the waveguide through the electrodes (typically different from each other) and produce laser output. A wavelength discriminator, an optical detector, and a wavelength-control circuit act as a wavelength-control feedback mechanism to generate a wavelength control current that flows through one laser electrode or the other, or through both electrodes with opposite polarities. Phase noise on the laser output can be reduced at modulation frequencies exceeding several hundred kHz up to one or several tens of MHz or more. The laser-wavelength can be swept while exhibiting reduced phase noise.
H01S 3/06 - Construction or shape of active medium
H01S 5/0625 - Arrangements for controlling the laser output parameters, e.g. by operating on the active medium by varying the potential of the electrodes in multi-section lasers
H01S 5/026 - Monolithically integrated components, e.g. waveguides, monitoring photo-detectors or drivers
G02F 1/01 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour
An optical device comprises a fiber having a cladding and a core, and a target PIC waveguide having a cladding and a core. The cladding on one side of the input fiber is removed at the end of the fiber and a flat surface is created along the fiber core, close to the core, exposing the fiber core. A flat-bottomed channel having an in-plane angle with respect to the symmetric axis of the PIC waveguide is fabricated on the top layer of the PIC waveguide in the coupling area, exposing the upper surface of the tapered planar waveguide. The flat surface of the fiber and the top surface of the waveguide is contacting, so the core of the fiber is intersected at an angle with respect to the symmetric axis of the target waveguide and close together at the intersection as an interacting region to define a hybrid waveguide.
G02B 6/30 - Optical coupling means for use between fibre and thin-film device
G02B 6/28 - Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
G02B 6/122 - Basic optical elements, e.g. light-guiding paths
14.
Integrated optic wavemeter and method for fiber optic gyroscopes scale factor stabilization
A system for stabilizing a scale factor associated with an optic rotation sensor comprises an optic rotation sensor that generates an optic signal in response to a rotation of the optic rotation sensor. A sensor detection system produces a rotation signal as a function of the optic signal and rotation of the optic rotation sensor. A first waveguide guides a portion of the optic signal for an interaction length, and produces a first processed optic signal. A second waveguide receives a portion of the optic signal from first waveguide through evanescent coupling, and produces a second processed optic signal. A wavemeter detector receives the optic signals and measures the effective interferometric wavelength (EIW) of the light based on the optic signals. A scale factor correction system receives the rotation signal and the EIW, and measures the correct rotation signal by processing the rotation signal and the EIW.
G01C 19/72 - Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams with counter-rotating light beams in a passive ring, e.g. fibre laser gyrometers
H01S 5/0687 - Stabilising the frequency of the laser
G01J 3/26 - Generating the spectrumMonochromators using multiple reflection, e.g. Fabry-Perot interferometer, variable interference filter
G01J 9/02 - Measuring optical phase differenceDetermining degree of coherenceMeasuring optical wavelength by interferometric methods
G02B 6/28 - Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
15.
Photonic integrated circuit for an interference fiber optic gyroscope (IFOG)
The described embodiments relate to a photonic integrated circuit (PIC) for use in a fiber optic gyroscope (FOG). Some embodiments describe a PIC with connectors for coupling to external components such as a light source, a photodetector and a fiber coil, with beamsplitting devices (e.g., couplers), waveguide and other photonic components integrated on the PIC. Some embodiments describe a hybrid PIC (HPIC) with the PIC, light source and photodetector attached to a common submount, and with connectors for coupling to a fiber coil. Other embodiments describe an extended PIC (EPIC) that integrates the PIC components, the light source, the photodetector, and other components (e.g., a wavemeter) on a common substrate. The described embodiments may also include a detection/feedback circuit that provides control signals and other parameters to the PIC, HPIC, or EPIC, and receives output signals from the PIC, HPIC, or EPIC.
G01C 19/72 - Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams with counter-rotating light beams in a passive ring, e.g. fibre laser gyrometers
G02B 6/42 - Coupling light guides with opto-electronic elements
09 - Scientific and electric apparatus and instruments
40 - Treatment of materials; recycling, air and water treatment,
42 - Scientific, technological and industrial services, research and design
Goods & Services
semiconductors; semiconductor devices; semiconductor chips; semiconductor power elements; semiconductor wafers; wafers for integrated circuits; integrated circuit module; electronic integrated circuits; integrated circuits; integrated circuit cards and components; laser diodes; laser chips in the nature of lasers, not for medical purposes; photodiodes; photodiode chips; photodiode detectors; circuit boards provided with integrated circuits; lasers, not for medical purposes; laser equipment for non-medical purposes; electronic and optical [ communications instruments and ] components, namely, optical and digital transmitters; optical receivers; optical transceivers; optical sensors; [ optical communications systems comprised of optical and electronic hardware in the nature of optical shutters and reflectors and computer software for the transmission of data between two points; telecommunications networking hardware in the nature of devices for transporting and aggregating voice, data, and video communications across multiple network infrastructures and communications protocols; ] electric sensors; electric navigational instruments; electronic navigational and positioning apparatus and instruments; integrated circuits for use in navigation; [ microwave transmitters and receivers; ] amplifiers; optical semiconductor amplifiers; fiber optics; fiber optic transmitters; optical fibers; fiber optic cables; fiber optic switches in the nature of telecommunication switches; gyroscopes; fiber optic gyroscopes; fiber optic instruments, namely, electronic navigation systems; fiber optic instruments, namely, gyro-based electronic navigation systems; computer software and firmware for operating, controlling, and using the aforementioned goods; firmware and software for communication, [ wireless communication, ] connectivity, interoperability, and navigation custom manufacture of semiconductors, semiconductor chips, wafers, circuits, integrated circuits, lasers, photodiodes, data processing equipment, circuit boards, printed circuit boards, optical communications apparatus and instruments, microprocessors, software, firmware, sensors, navigational and positioning apparatus and instruments, transmitters, receivers, amplifiers, fiber optics, switches, gyroscopes, and parts and components for the aforementioned goods; manufacturing services for others in the field of semiconductors, semiconductor chips, wafers, circuits, integrated circuits, lasers, photodiodes, data processing equipment, circuit boards, printed circuit boards, optical communications apparatus and instruments, microprocessors, software, firmware, sensors, navigational and positioning apparatus and instruments, transmitters, receivers, amplifiers, fiber optics, switches, gyroscopes, and parts and components for the aforementioned goods design, custom design, development, consultancy, research, and engineering in the field of semiconductors, semiconductor chips, wafers, circuits, integrated circuits, lasers, photodiodes, data processing equipment, circuit boards, printed circuit boards, optical communications apparatus and instruments, microprocessors, software, firmware, sensors, navigational and positioning apparatus and instruments, transmitters, receivers, amplifiers, fiber optics, switches, gyroscopes, and parts and components for the aforementioned goods
17.
Modulated laser source and methods of its fabrication and operation
A modulated semiconductor laser source includes a waveguide on a semiconductor substrate; first and second reflectors; a laser electrode; an optical modulator; and a laser-electrode electrical circuit. The reflectors and a resonator segment of the waveguide define a laser resonator with laser output transmitted through the second reflector. The laser electrode is positioned over the resonator segment and a laser current flows through the laser electrode into the resonator segment to produce optical gain. The modulator receives and modulates the laser output, in response to a primary modulation signal, to produce a modulated output optical signal. The laser-electrode circuit is coupled to the laser electrode and derives from the primary modulation signal a laser-electrode secondary modulation current, optimized to reduce chirp in the modulated output signal, that flows through the laser electrode into or out of the resonator segment in addition to the laser current.
H01S 5/20 - Structure or shape of the semiconductor body to guide the optical wave
H01S 5/10 - Construction or shape of the optical resonator
H01S 5/026 - Monolithically integrated components, e.g. waveguides, monitoring photo-detectors or drivers
H01S 5/12 - Construction or shape of the optical resonator the resonator having a periodic structure, e.g. in distributed feedback [DFB] lasers
H01S 5/0625 - Arrangements for controlling the laser output parameters, e.g. by operating on the active medium by varying the potential of the electrodes in multi-section lasers
H01S 3/10 - Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
H01S 5/343 - Structure or shape of the active regionMaterials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well [SQW] lasers, multiple quantum well [MQW] lasers or graded index separate confinement heterostructure [GRINSCH] lasers in AIIIBV compounds, e.g. AlGaAs-laser
H01S 5/10 - Construction or shape of the optical resonator
H01S 5/026 - Monolithically integrated components, e.g. waveguides, monitoring photo-detectors or drivers
G02F 1/01 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour
G02F 1/017 - Structures with periodic or quasi periodic potential variation, e.g. superlattices, quantum wells
G02F 1/025 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour based on semiconductor elements having potential barriers, e.g. having a PN or PIN junction in an optical waveguide structure
H01S 5/0625 - Arrangements for controlling the laser output parameters, e.g. by operating on the active medium by varying the potential of the electrodes in multi-section lasers
H01S 5/50 - Amplifier structures not provided for in groups
H04B 10/2575 - Radio-over-fibre, e.g. radio frequency signal modulated onto an optical carrier
A method of making an optical modulator by determining the material composition of the quantum well region in the waveguide portion of the modulator so that the modulator is transparent at a gain peak wavelength that is greater than the predetermined wavelength by a predetermined amount, and fabricating the modulator with the determined material composition.
H01S 5/026 - Monolithically integrated components, e.g. waveguides, monitoring photo-detectors or drivers
H01S 5/10 - Construction or shape of the optical resonator
H01S 5/343 - Structure or shape of the active regionMaterials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well [SQW] lasers, multiple quantum well [MQW] lasers or graded index separate confinement heterostructure [GRINSCH] lasers in AIIIBV compounds, e.g. AlGaAs-laser
H01S 5/0625 - Arrangements for controlling the laser output parameters, e.g. by operating on the active medium by varying the potential of the electrodes in multi-section lasers
G02F 1/01 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour
G02F 1/025 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour based on semiconductor elements having potential barriers, e.g. having a PN or PIN junction in an optical waveguide structure
H04B 10/2575 - Radio-over-fibre, e.g. radio frequency signal modulated onto an optical carrier
2 material, a forcer electrode configured to apply an electrical force on the hemisphere to cause the hemisphere to oscillate, and one or more sensor electrodes disposed in proximity to the hemisphere and configured to sense an orientation of a vibration pattern of the hemispherical resonator gyroscope.
C23C 16/22 - Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the deposition of inorganic material, other than metallic material
G01C 19/5691 - Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using the phase shift of a vibration node or antinode of essentially three-dimensional vibrators, e.g. wine glass-type vibrators
C23C 28/04 - Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of main groups , or by combinations of methods provided for in subclasses and only coatings of inorganic non-metallic material
C23C 28/00 - Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of main groups , or by combinations of methods provided for in subclasses and
An optical modulator including an information-containing radio frequency signal input; a semiconductor device having an optical input optically for receiving the coherent light beam, and a electrode connected to said radio frequency signal input and having a modulated bias potential so that current is generated in the second semiconductor device and extracted therefrom, while the coherent light beam is optically modulated by the signal changing the carrier density in the semiconductor device.
An optical modulator including an information-containing radio frequency signal input; a semiconductor device having an optical input optically for receiving the coherent light beam, and a electrode connected to said radio frequency signal input and having a modulated bias potential so that current is generated in the second semiconductor device and extracted therefrom, while the coherent light beam is optically modulated by the signal changing the carrier density in the semiconductor device.
H01S 5/10 - Construction or shape of the optical resonator
H01S 5/50 - Amplifier structures not provided for in groups
H01S 5/343 - Structure or shape of the active regionMaterials used for the active region comprising quantum well or superlattice structures, e.g. single quantum well [SQW] lasers, multiple quantum well [MQW] lasers or graded index separate confinement heterostructure [GRINSCH] lasers in AIIIBV compounds, e.g. AlGaAs-laser
H01S 5/20 - Structure or shape of the semiconductor body to guide the optical wave
H01S 5/026 - Monolithically integrated components, e.g. waveguides, monitoring photo-detectors or drivers
G02F 1/01 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour
G02F 1/025 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour based on semiconductor elements having potential barriers, e.g. having a PN or PIN junction in an optical waveguide structure
H04B 10/2575 - Radio-over-fibre, e.g. radio frequency signal modulated onto an optical carrier
A torsional gyroscope is provided that includes: a pickup tine and a drive tine of piezoelectric material, pickup electrodes disposed along the pickup tine, drive electrodes disposed along the drive tine, and a drive mass. The drive tine has a first end attached to the pickup tine and is transverse to the drive tine. The drive mass is attached to a second end of the drive tine opposite the first end of the drive tine. An electric field applied to the drive electrodes induces a rotational oscillation of the drive tine causing the drive tine to rotate about the first axis, inducing the drive mass to rotate about the first axis. Angular rotation of the drive mass along a third axis induces a torque in the pickup tine that induces an electric field in the pickup tine that induces an electrical charge to build up in the pickup electrodes.
G01C 19/5607 - Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using vibrating tuning forks
G01C 19/5642 - Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using vibrating bars or beams
G01C 19/5719 - Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using planar vibrating masses driven in a translation vibration along an axis
G01C 19/5755 - Structural details or topology the devices having a single sensing mass
G01C 19/56 - Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
26.
Method of fabricating and operating an optical modulator
A method of making an optical modulator by determining the material composition of the quantum well region in the waveguide portion of the modulator so that the modulator is transparent at a gain peak wavelength that is greater than the predetermined wavelength by a predetermined amount, and fabricating the modulator with the determined material composition.
H01S 5/026 - Monolithically integrated components, e.g. waveguides, monitoring photo-detectors or drivers
G02F 1/01 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour
G02F 1/025 - Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulatingNon-linear optics for the control of the intensity, phase, polarisation or colour based on semiconductor elements having potential barriers, e.g. having a PN or PIN junction in an optical waveguide structure
H04B 10/2575 - Radio-over-fibre, e.g. radio frequency signal modulated onto an optical carrier
27.
Multi-axis fiber optic gyroscope with single light source
A fiber optic gyroscope including a non-coherent light source for producing a first beam of light, an optical circulator in the path of said first beam for providing polarized second and third beams, respectively, with polarization orthogonal to each other, and a time division multiplexer in the path of the second and third beams. A first planar optical fiber loop is coupled to the time division multiplexer and has a first end and a second end coupled to the second and third beams respectively during a first time period. A second planar optical fiber loop is coupled to the time division multiplexer and has a first end and a second end coupled to the second and third beams respectively during a second time period subsequent to the first time period.
G01C 19/72 - Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams with counter-rotating light beams in a passive ring, e.g. fibre laser gyrometers
A compact fiber optic gyroscope including a first housing; a transceiver module disposed in the first housing, the transceiver module including a second housing; a non-coherent light source disposed in the second housing for producing a first beam of light; a single lens for focusing the first beam of light; an optical circulator disposed in the second housing and in the path of the first beam of light to produce polarized second and third beams respectively, with polarization orthogonal to each other; and first and second photodiodes disposed in the second housing and coupled to the optical circulator, wherein the first photodiode is a transmit monitor photodiode coupled to the second beam, and the second photodiode is a receiver photodiode. The first housing further includes a planar optical fiber loop having a first end and a second end; a phase modulator coupled to the third beam emitted from the transceiver module to produce fourth and fifth beams coupled to the first and the second end respectively of the optical fiber loop respectively, and for receiving the return sixth and seventh beams from the second and the first ends respectively of the optical fiber loop.
G01C 19/72 - Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams with counter-rotating light beams in a passive ring, e.g. fibre laser gyrometers
A system for determining a combined velocity rotation compensation and sculling compensation in an inertial navigation system includes: gyroscopes configured to provide a measured angular rotation rate with components from three orthogonal axes; accelerometers configured to provide a measured specific force with components from three orthogonal axes; and a processor configured to calculate a first combined velocity rotation compensation and sculling compensation at a single computational rate, the processor configured to: calculate a first cross product of an instantaneous angular rotation rate and a change in the measured specific force during a first interval; and sum the first cross product with a second cross product of a fraction of the change in the specific force during the second interval and the change in the measured angular rate during the first interval; where the first and second intervals are each one cycle of the single computational rate.
G01C 21/10 - NavigationNavigational instruments not provided for in groups by using measurement of speed or acceleration
G01C 21/18 - Stabilised platforms, e.g. by gyroscope
G01C 21/16 - NavigationNavigational instruments not provided for in groups by using measurement of speed or acceleration executed aboard the object being navigatedDead reckoning by integrating acceleration or speed, i.e. inertial navigation
G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
30.
Gyroscope and devices with structural components comprising HfO2-TiO2 material
2 material, a forcer electrode configured to apply an electrical force on the hemisphere to cause the hemisphere to oscillate, and one or more sensor electrodes disposed in proximity to the hemisphere and configured to sense an orientation of a vibration pattern of the hemispherical resonator gyroscope.
G01C 19/56 - Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
G01C 19/5691 - Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using the phase shift of a vibration node or antinode of essentially three-dimensional vibrators, e.g. wine glass-type vibrators
C23C 28/04 - Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of main groups , or by combinations of methods provided for in subclasses and only coatings of inorganic non-metallic material
C23C 28/00 - Coating for obtaining at least two superposed coatings either by methods not provided for in a single one of main groups , or by combinations of methods provided for in subclasses and
Methods of attaching an optical line to a phase modulator in a fiber optic gyroscope. The methods include positioning at least one end of the optical line relative to a side of the phase modulator. The end of the optical line may have a first non-perpendicular angle and the side of the phase modulator may have a second non-perpendicular angle. The end of the optical line may be attached to the side of the phase modulator with the end of the optical line being non-parallel to the side of the phase modulator. The optical line may be an optical coil or a light path.
G01C 19/72 - Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams with counter-rotating light beams in a passive ring, e.g. fibre laser gyrometers
G01C 19/64 - Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams
G02B 6/32 - Optical coupling means having lens focusing means
G02B 6/30 - Optical coupling means for use between fibre and thin-film device
Techniques are provided for reducing mount vibration in an inertial rate sensor (IRS). For example, if oscillation in an IRS's vibratory members, vibrating along a first axis, cause displacement in the IRS's mount along a second axis, the vibratory members can be aligned so that the vibratory members have some component of movement along the second axis during oscillation. This component of movement can help reduce the displacement of the IRS's mount along the second axis. It can further reduce sensitivity to changes in the boundary conditions of an IRS (e.g., vibrations and other movements at the mount from forces external to the IRS). Vibratory members further can have portions of increased mass at the vibratory members' tips, which can impact the alignment of the vibratory members. These examples, however, are not exhaustive.
G01C 19/5607 - Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using vibrating tuning forks
G01C 19/5621 - Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces using vibrating tuning forks the devices involving a micromechanical structure
33.
Method and system for initial quaternion and attitude estimation
Techniques are provided to determine an initial quaternion transform that is used to transform measurements received from accelerometer, rate sensor and inertial reference subsystems from a vehicle coordinate frame to an inertial navigation frame. Methods disclosed determine corrective angular rates to use as a feedback signal to rotate the quaternion transform to counter errors that result when transforming a gravity vector and an inertial reference vector (e.g., a magnetic North reference vector) that are being measured by the accelerometer and an inertial reference subsystems, respectively. The initial quaternion determination is performed during a time period when the only substantial acceleration on the vehicle is due to gravity. The initial quaternion can be used for processing various guidance, navigation and control functions.
Inertial sensor having a body with first and second cavities on opposite sides thereof, a sensing element in the first cavity, electronic circuitry in the second cavity, electrical conductors interconnecting the sensing element and the circuitry, and leads connected electrically to the circuitry and extending from the body for mounting the sensor and making connections with the circuitry.
H01L 23/057 - ContainersSeals characterised by the shape the container being a hollow construction and having an insulating base as a mounting for the semiconductor body the leads being parallel to the base
G01C 19/5783 - Mountings or housings not specific to any of the devices covered by groups
35.
Inertial sensor with dual cavity package and method of fabrication
Inertial sensor having a body with first and second cavities on opposite sides thereof, a sensing element in the first cavity, electronic circuitry in the second cavity, electrical conductors interconnecting the sensing element and the circuitry, and leads connected electrically to the circuitry and extending from the body for mounting the sensor and making connections with the circuitry.
A circuit controlling the gain of an amplifier in an optical transmitter used for optical communication, including a detection circuit for measuring the power of the RF input to a laser; a gain controller or controlling a gain of an amplifier, and a switch connected to the gain controller, wherein the gain controller is adapted, in response to an activation of a switch, to: (i) automatically vary gain of the amplifier, and (ii) set the gain of the amplifier at a level corresponding to a reduction in the noise and/or distortion associated with the transmitter.
A fiber optic gyroscope including an optical circulator in the path of said first and second beams for providing polarized first and second beams of identical polarization. A phase modulator couples the first and second beams to the first and second end respectively of the fiber loop, and couples for receiving the return first and second beams from the second and first ends respectively of the fiber loop. First and second photodiodes are coupled to the optical circulator for receiving the optical signal from the first and second return beams.
G01C 19/72 - Gyrometers using the Sagnac effect, i.e. rotation-induced shifts between counter-rotating electromagnetic beams with counter-rotating light beams in a passive ring, e.g. fibre laser gyrometers
38.
Dithering mechanism for eliminating zero-rate bias in a gyroscope
Dithering mechanism and method for eliminating the effects of zero-rate bias in a rate sensor or gyroscope. Both continuously moving and indexing embodiments are disclosed. The mechanism includes a first part mounted in a fixed position centered about a dither axis perpendicular to the input axis of the gyroscope, a second part disposed coaxially of the first part and affixed to the sensing element of the gyroscope, and a plurality of piezoelectrically driven quartz flexure beams extending radially between the first and second parts for dithering the second part about the dither axis. In some embodiments, the dithering mechanism is formed separately from and affixed to the sensing element of the gyroscope, and in others it is formed integrally with the sensing element. In the indexing embodiments, radial arms and fixed stops limit movement of the mechanism between two fixed positions, and drive signals and holding potentials are applied alternately to dither the mechanism between the two positions and to hold it alternately in those positions during successive data acquisition periods.
Dithering mechanism and method for eliminating the effects of zero-rate bias in a rate sensor or gyroscope. Both continuously moving and indexing embodiments are disclosed. The mechanism includes a first part mounted in a fixed position centered about a dither axis perpendicular to the input axis of the gyroscope, a second part disposed coaxially of the first part and affixed to the sensing element of the gyroscope, and a plurality of piezoelectrically driven quartz flexure beams extending radially between the first and second parts for dithering the second part about the dither axis. In some embodiments, the dithering mechanism is formed separately from and affixed to the sensing element of the gyroscope, and in others it is formed integrally with the sensing element. In the indexing embodiments, radial arms and fixed stops limit movement of the mechanism between two fixed positions, and drive signals and holding potentials are applied alternately to dither the mechanism between the two positions and to hold it alternately in those positions during successive data acquisition periods.
This invention relates to an optical fiber composite comprising an asymmetric optical fiber comprising a first end with a substantially non-circular cross-section, and a substantially circular clad optical fiber comprising a tapered end section which has a substantially non-circular cross section and where the asymmetric optical fiber and the substantially circular clad optical fiber are spliced together at the first and second ends. The invention also relates to methods of making such optical fiber composites and devices that include such optical fiber composites.
Angular rate sensor for detecting rotation about first and second mutually perpendicular axes which has first and second masses coupled together for torsional drive mode oscillation of equal amplitude and opposite phase about third axes which are perpendicular to the first and second axes. The first mass is mounted for oscillation about the second axis in response to Coriolis forces produced by rotation about the first axis, and the second mass is mounted for oscillation about the first axis in response to Coriolis forces produced by rotation about the second axis. In some disclosed embodiments, the rate sensor also includes a pair of accelerometer masses which are connected together for torsional movement of equal amplitude and opposite phase about axes parallel to the third axes in response to acceleration along the second axis and for torsional movement of equal amplitude and opposite phase about axes parallel to the second axis in response to acceleration along the third axes.
A distortion circuit is provided for correcting the distortion from a nonlinear circuit element by generating a frequency dependent signal having a sign opposite to the distortion signal produced by the nonlinear circuit and substantially the same magnitude. The distortion circuit includes an input signal and a first nonlinear device coupled to the input signal for generating a first signal and where the first nonlinear device has a first bias level. Also included is a second nonlinear device different from same first nonlinear device and coupled to the first nonlinear device for modifying the first signal to produce an output second signal, the second nonlinear device having a second bias level. A bias control means is provided for adjusting the first and said second bias levels so that the magnitude, phase and frequency of the output second signal can be adjusted.
H04B 10/18 - Arrangements for reducing or eliminating distortion or dispersion, e.g. equalisers
H04B 10/00 - Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
H03F 1/34 - Negative-feedback-circuit arrangements with or without positive feedback
H03F 3/08 - Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements with semiconductor devices only controlled by light
H03F 5/00 - Amplifiers with both discharge tubes and semiconductor devices as amplifying elements
