Tokyo Institute of Technology

Japan Aviation Electronics Industry, Limited

Mitsubishi Heavy Industries Limited

Osaka University

Institute of Science Tokyo

Mikio Kozuma

Atsushi Tanaka

Ryotaro Inoue

Toshiyuki Hosoya

Kento Taniguchi

Yuichiro Kamino

Kazunori Yoshioka

Takashi Mukaiyama

Utako Tanaka

Seiichi Morimoto

An adjuster performs simultaneous irradiation of M laser beams to an atomic beam, where M is a predetermined integer satisfying 3≤M. The course of each of the M laser beams intersects with the course of the atomic beam. A component, in a direction perpendicular to the course of the atomic beam, of the sum of radiation pressure vectors that the M laser beams respectively have is zero. A component, in a direction of the course of the atomic beam, of the sum of the radiation pressure vectors that the M laser beams respectively have is negative for atoms having speeds greater than a predetermined speed, and positive for atoms having speeds smaller than the predetermined speed.

Inertial sensor, atomic interferometer, method for adjusting speeds of atoms, and apparatus for adjusting speeds of atoms

To provide a light source device for a fiber optic gyroscope capable of broadening the bandwidth of the laser light and improving stability of a scale factor. A light source device for a fiber optic gyroscope configured to drive a fiber optic gyroscope includes: a laser light source, a stabilizing part, and a bandwidth broadening part. The laser light sourceemits a laser light of a predetermined frequency. The stabilizing partstabilizes the predetermined frequency of the laser light emitted from the laser light source. The bandwidth broadening partmakes the laser light stabilized by the stabilizing partinto a light having a continuous broadband spectrum.

Light source device for fiber optic gyroscope and fiber optic gyroscope using the same

An adjuster performs simultaneous irradiation of M laser beams to an atomic beam, where M is a predetermined integer satisfying 3≤M. The course of each of the M laser beams intersects with an approach path of the atomic beam. A component, in a direction perpendicular to the approach path of the atomic beam, of the sum of radiation pressure vectors that the M laser beams respectively have is non-zero. A component, in a direction of the approach path of the atomic beam, of the sum of the radiation pressure vectors that the M laser beams respectively have is negative for atoms having speeds greater than the predetermined speed, and positive for the atoms having speeds smaller than the predetermined speed.

Inertial sensor, atomic interferometer, method for adjusting speed and course of atomic beam, and apparatus for adjusting speed and course of atomic beam

A vertical deflection estimation device usable for inertial navigation includes: a gravity gradiometer (), a known vertical deflection library part (), a high frequency extraction part (), and an estimation part (). The gravity gradiometer () measures vertical deflection in accordance with positional movement of the gravity gradiometer (). The known vertical deflection library part obtains known coarse information of vertical deflection on map in accordance with the positional movement of the gravity gradiometer (). The high frequency extraction part () extracts, from the measured vertical deflection, a high spatial frequency component of the measured vertical deflection. The estimation part () corrects the measured vertical deflection to derive estimated vertical deflection as highly accurate vertical deflection by combining the known coarse information of vertical deflection on map with the extracted high spatial frequency component of the measured vertical deflection.

Vertical deflection estimation device

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.

Atomic gyroscope and atomic interferometer

An atomic beam is irradiated with a first laser beam, a second laser beam, and a third laser beam. The first laser beam and the third laser beam each have a wavelength corresponding to a transition between a ground state and a first excited state. The second laser beam has a wavelength corresponding to a transition between the ground state and a second excited state. First, atoms each having a smaller velocity component than a predetermined velocity in a direction orthogonal to the traveling direction of the atomic beam are changed from the ground state to the first excited state by the first laser beam. Subsequently, a momentum is provided for individual atoms in the ground state by the second laser beam, which removes the atoms from the atomic beam. Finally, atoms in the first excited state are returned from the first excited state to the ground state by the third laser beam.

Method of collimating atomic beam, apparatus for collimating atomic beam, atomic interferometer, and atomic gyroscope

A geoid calculation data is collected easily. A geoid calculation data collection device of the present invention comprises an inertial measurement data acquisition part, a comparison data acquisition part, and a recording part. In the inertial measurement data acquisition part, data related to velocity, position, and attitude angle is acquired as inertially-derived data based on an output of an inertial measurement part having a three-axis gyro and a three-axis accelerometer attached to a moving body. In the comparison data acquisition part, data related to velocity is acquired as comparison data from a source other than the inertial measurement part. In the recording part, inertially-derived data and comparison data are recorded in association with each other. In the inertial measurement part, a bias stability is acquired that allows error arising from plumb line deviation to be distinguished to a predetermined degree.

Geoid measurement method, geoid measurement apparatus, geoid estimation device, and geoid calculation data collection device

The present invention reduces measurement time. A gyroscope of the present invention includes a planar ion trap part, a microwave irradiation part, a laser irradiation part and a measurement part. The planar ion trap part includes two rf electrodes and two DC electrode rows, and forms ion traps that trap one ion on a substrate, a normal direction of the surface of the planar ion trap part corresponds to a z direction. The rf electrodes are disposed in the x direction on the substrate at a predetermined interval. The DC electrode rows are disposed in the x direction on the substrate so as to sandwich the two rf electrodes. The DC electrode rows each include at least five DC electrodes in the x direction. The trapped ions are spaced so as not to interfere with each other. The microwave irradiation part irradiates the ions with &#x3c0;/2 microwave pulses.

Gyroscope and angle measurement method

A change in geoid height is measured easily. A geoid measurement method of the present invention executes an inertial measurement data acquiring step, a comparison data acquiring step, a state variable estimating step, and a geoid calculating step. In the inertial measurement data acquiring step, data related to velocity, position, and attitude angle is acquired as inertially-derived data based on the output of an inertial measurement part having a three-axis gyro and a three-axis accelerometer attached to a moving body. In the comparison data acquiring step, data related to velocity is acquired as comparison data from a source other than the inertial measurement part. In the state variable estimating step, state variables including a plumb line deviation are estimated by using the inertially-derived data and the comparison data to apply a Kalman filter in which the plumb line deviation is included in the state variables.

Growing community of inventors

Kanagawa, Japan

Mikio Kozuma