Patent classifications
G01C19/72
Semi-finished Product for the Construction of a Gyroscope and Gyroscope Including the Semi-finished Product
A semi-finished product for the realization of a gyroscope, including: a single package and a single substrate on which it is attached; a super luminescent diode with a polarized light source; a PIC in which a waveguide group is made of an optical coupling device arranged for coupling the light source with the PIC; wherein on the PIC at least one photodiode is formed or hybridized in order to receive a return light beam from the PIC.
Semi-finished Product for the Construction of a Gyroscope and Gyroscope Including the Semi-finished Product
A semi-finished product for the realization of a gyroscope, including: a single package and a single substrate on which it is attached; a super luminescent diode with a polarized light source; a PIC in which a waveguide group is made of an optical coupling device arranged for coupling the light source with the PIC; wherein on the PIC at least one photodiode is formed or hybridized in order to receive a return light beam from the PIC.
INTERFEROMETRIC FIBER-OPTIC GYROSCOPE WITH REDUCED COMMON MODE PHASE NOISES AND POLARIZATION CROSSTALK FOR ENHANCED MEASUREMENT SENSITIVITY AND ACCURACY
An improved-type of interferometric fiber-optic gyroscope (FOG) is proposed, which is used for the observation and measurement of the Sagnac effect to determine the angular speed of a rotational movement with enhanced measurement sensitivity and accuracy. The improved FOG is characterized by the combined use of a polarization-maintaining mechanism, a symmetric beam-splitting configuration for the 3×3 directional coupler, a common optical path for the opposing beams, and a pair of photo detectors for the detection of a pair of differential phase signals that indicate the angular speed of the rotational movement. The combined use of these approaches can help significantly eliminate and reduce the common mode phase noises caused by polarization crosstalk to a minimum possible level that has never been achieved by the conventional FOGs, thus significantly enhancing the measurement sensitivity and accuracy to a much higher level.
ATOMIC GYROSCOPE AND ATOMIC INTERFEROMETER
An atomic interferometer includes: an optical system including an optical modulating device that includes: an optical fiber for a first laser beam to propagate therein; and a frequency shifter connected to the optical fiber and configured to shift the frequency of the first laser beam, the optical system being configured to generate a moving standing light wave from counter-propagation of the first laser beam from the optical modulating device and a second laser beam; and an interference system for making an atomic beam interact with three or more moving standing light waves including the moving standing light wave.
FOLDING SAGNAC INERTIA MEASUREMENT UNIT
Disclosed is an improved Sagnac interferometer sensor for inertial navigation and guidance systems (e.g., inertial measurement units (IMUs)) that affords a reduced area architecture. The sensor implements optical folding architectures and techniques to increase the optical path length of the Sagnac interferometer. The folding optical architecture increases the total optical path, which thereby increases the total phase difference between two counter-rotating optical beams in the Sagnac interferometer. The technique increases accuracy and durability of IMUs without the need for an increase in size, weight, and cost.
FOLDING SAGNAC INERTIA MEASUREMENT UNIT
Disclosed is an improved Sagnac interferometer sensor for inertial navigation and guidance systems (e.g., inertial measurement units (IMUs)) that affords a reduced area architecture. The sensor implements optical folding architectures and techniques to increase the optical path length of the Sagnac interferometer. The folding optical architecture increases the total optical path, which thereby increases the total phase difference between two counter-rotating optical beams in the Sagnac interferometer. The technique increases accuracy and durability of IMUs without the need for an increase in size, weight, and cost.
Atom chip for ultracold atom preparation and loading into an integrated optical waveguide evanescent field trip
An embodiment of an integrated atom chip used for measuring atoms is discussed. One or more magnetic traps integrated with an optical waveguide that is imprinted onto the integrated atom chip facilitate loading of the atoms into an evanescent field optical trap of the optical waveguide in order to measure the atoms. The two or more stages of cooling are used to progressively cool the atoms from an initial temperature down to a final temperature of the atoms when mode matched and loaded into the evanescent field optical trap of the optical waveguide.
KIND OF LOW MAGNETIC SENSITIVITY PM-PCF BASED ON MECHANICAL BUFFER
The low magnetic sensitivity PM-PCF based on mechanical buffer is obtained by adding buffer structures in the cladding layer of the photonic crystal fiber. In the center of the fiber, the core region contains at least 3 layers of air-holes, enclosed by the cladding layer. The buffer structures are placed in the cladding layer. These buffer structures are formed by replacing silica of any shape by air, and are symmetrically located in X-axis and Y-axis directions to achieve mechanical isotropy. The buffer structures improve the fiber's performance in fiber coiling and stress conditions. Therefore, the fiber optic gyroscope using the PM-PCF can do without a magnetic shield, thus greatly reducing the weight of the fiber optic gyroscope and extending the scope of its application. Compared with the conventional commercial PCF, the PM-PCF provides the fiber optic gyroscope with lower temperature sensitivity and improved accuracy.
KIND OF LOW MAGNETIC SENSITIVITY PM-PCF BASED ON MECHANICAL BUFFER
The low magnetic sensitivity PM-PCF based on mechanical buffer is obtained by adding buffer structures in the cladding layer of the photonic crystal fiber. In the center of the fiber, the core region contains at least 3 layers of air-holes, enclosed by the cladding layer. The buffer structures are placed in the cladding layer. These buffer structures are formed by replacing silica of any shape by air, and are symmetrically located in X-axis and Y-axis directions to achieve mechanical isotropy. The buffer structures improve the fiber's performance in fiber coiling and stress conditions. Therefore, the fiber optic gyroscope using the PM-PCF can do without a magnetic shield, thus greatly reducing the weight of the fiber optic gyroscope and extending the scope of its application. Compared with the conventional commercial PCF, the PM-PCF provides the fiber optic gyroscope with lower temperature sensitivity and improved accuracy.
PROCESS FLOW FOR FABRICATING INTEGRATED PHOTONICS OPTICAL GYROSCOPES
Aspects of the present disclosure are directed to configurations of compact ultra-low loss integrated photonics-based waveguides for optical gyroscope applications, and the methods of fabricating those waveguides for ease of large scale manufacturing. Four main process flows are described: (1) process flow based on a repeated sequence of oxide deposition and anneal; (2) chemical-mechanical polishing (CMP)-based process flow followed by wafer bonding; (3) Damascene process flow followed by oxide deposition and anneal, or wafer bonding; and (4) CMP-based process flows followed by oxide deposition. Any combination of these process flows may be adopted to meet the end goal of fabricating optical gyroscope waveguides in one or more layers on a silicon substrate using standard silicon fabrication technologies.