公开(公告)号：JP2000036630A

公开(公告)日：2000-02-02

申请号：JP18806699

申请日：1999-05-28

Applicant: LITTON SYSTEMS INC

Inventor： ROZELLE DAVID M ,  MICHAL RONALD J ,  LAM LEO K ,  CAPPI JOHN F

IPC: H01S3/094 ,  G01C19/72 ,  H01S3/06 ,  H01S3/067

Abstract: PROBLEM TO BE SOLVED: To eliminate the backward reflection of exciting light by providing a stimulation light source which gives stimulation light to an optical fiber and guides the light to a first light shutter. SOLUTION: An optical light source is constituted in such a way that the light outputted from a first light shutter 18 is inputted to a wavelength multiplexer 26 and a gain fiber 34 is connected to the multiplexer 26 so that the wide-band light which is optically stimulated by stimulation light and outputted may be propagated to the multiplexer. In addition, an output optical fiber 29 is also connected to the multiplexer 26 so that part of the wide-band light sent from the gain fiber 34 may be guided to a second light shutter 50 and inputted to a fiber optic rotation sensor.

公开(公告)号：WO0003201A3

公开(公告)日：2000-04-20

申请号：PCT/US9914495

申请日：1999-06-25

Applicant: LITTON SYSTEMS INC

Inventor： MICHAL RONALD J ,  LAM LEO K ,  ROZELLE DAVID M

IPC: G01C19/72 ,  H01S3/067 ,  H01S3/06

CPC classification number: H01S3/06795 ,  G01C19/721

Abstract: A system for performing scale factor stabilization of a broadband optical signal source used in fiber optic gyroscopes in radiation environments. A filter device is positioned in-line with the broadband light emitted by the gain fiber to attenuate light outside of the bandwidth of the filter device. The filter device allows a bandwidth of light narrower than the spectral width of the broadband light source to propagate through while attenuating all wavelengths of light outside of its operating bandwidth. Only the portion of the broadband source spectrum contained within the bandpass of the filter is selected out, thus narrowing the spectral width of the broadband fiber source. This narrower spectral width reduces the shift of centroid wavelength of the broadband fiber source which results when the gain fiber and other sensitive optical components are exposed to ionizing radiation.

Abstract translation: 用于在辐射环境中用于光纤陀螺仪的宽带光信号源进行比例因子稳定的系统。 过滤装置与由增益光纤发射的宽带光线成一直线排列以衰减过滤装置的带宽以外的光。 滤波器装置允许比宽带光源的光谱宽度窄的光的带宽传播，同时衰减其工作带宽以外的所有波长的光。 选择包含在滤波器带通内的宽带源频谱的部分，从而使宽带光纤源的频谱宽度变窄。 这种较窄的光谱宽度减小了当增益光纤和其他敏感光学元件暴露于电离辐射时导致的宽带光纤源的质心波长的偏移。

公开(公告)号：WO9603620A3

公开(公告)日：1996-05-30

申请号：PCT/US9509427

申请日：1995-07-26

Applicant: LITTON SYSTEMS INC

Inventor： PAVLATH GEORGE A ,  MICHAL RONALD J ,  PATTERSON RALPH A ,  HUANG SIDNEY XI-YI

IPC: G01C19/72 ,  G01R33/032

CPC classification number: G01C19/721

Abstract: A fiber optic sensing coil formed in a polarization-maintaining optical fiber has two optical fiber leads extending therefrom. A multifunction integrated optics chip linearly polarizes optical signals input to the sensing coil. Fiber optic leads formed of polarization-maintaining optical fiber extend from the multifunction integrated optics chip. The fiber optic multifunction integrated optics chip leads are arranged such that the linear polarization of optical signals output from the multifunction integrated optics chip is directed along one of the principal axes of birefringence of each of the fiber optic multifunction integrated optics chip leads. Splices are formed between corresponding the first sensing coil leads and the multifunction integrated optics chip leads. The sensing coil leads and the multifunction integrated optics chip leads are arranged such that their corresponding principal axes of birefringence are at angles of approximately 45° relative to one another. The first splice is formed a distance from the multifunction integrated optics chip such that a selected phase change between polarization components occurs in optical waves that propagate the distance L1 in the first multifunction integrated optics chip lead.

公开(公告)号：DE69409686T2

公开(公告)日：1998-08-13

申请号：DE69409686

申请日：1994-01-19

Applicant: LITTON SYSTEMS INC

Inventor： HUANG SIDNEY XI-YI ,  MICHAL RONALD J ,  PATTERSON RALPH A ,  PAVLATH GEORGE A

IPC: G01C19/72 ,  G02B6/00 ,  G02B6/44

Abstract: The compensated sensor coil includes arrangements formed at two leads of the sensor coil for compensating the bias shifts. One of such arrangements comprises at least one loop of optical fibre for compensating the effect induced by the magnetic field component oriented transverse to the axis of the sensor coil while the other comprises at least one loop oriented at a predetermined pitch angle for compensating the effect induced by a magnetic field component along the axis. The sensor coil is characterised by a number of randomly distributed fibre twist modes. In each case, a predetermined degree of twist of a preselected fibre twist mode is imposed upon the compensator loop for creating a counteracting, corrective Faraday effect The twist rate of a predetermined twist mode of the turn of the compensator is selected to offset the Faraday effect due to an applied magnetic field having a known orientation with respect to the axis of the sensor coil. The twist rate of the predetermined twist mode of the compensator is a function of the twist rate of the corresponding twist mode of the sensor coil.

公开(公告)号：DE69409686D1

公开(公告)日：1998-05-28

申请号：DE69409686

申请日：1994-01-19

Applicant: LITTON SYSTEMS INC

Inventor： HUANG SIDNEY XI-YI ,  MICHAL RONALD J ,  PATTERSON RALPH A ,  PAVLATH GEORGE A

IPC: G01C19/72 ,  G02B6/00 ,  G02B6/44

Abstract: The compensated sensor coil includes arrangements formed at two leads of the sensor coil for compensating the bias shifts. One of such arrangements comprises at least one loop of optical fibre for compensating the effect induced by the magnetic field component oriented transverse to the axis of the sensor coil while the other comprises at least one loop oriented at a predetermined pitch angle for compensating the effect induced by a magnetic field component along the axis. The sensor coil is characterised by a number of randomly distributed fibre twist modes. In each case, a predetermined degree of twist of a preselected fibre twist mode is imposed upon the compensator loop for creating a counteracting, corrective Faraday effect The twist rate of a predetermined twist mode of the turn of the compensator is selected to offset the Faraday effect due to an applied magnetic field having a known orientation with respect to the axis of the sensor coil. The twist rate of the predetermined twist mode of the compensator is a function of the twist rate of the corresponding twist mode of the sensor coil.

公开(公告)号：CA2172730A1

公开(公告)日：1996-02-08

申请号：CA2172730

申请日：1995-07-26

Applicant: LITTON SYSTEMS INC

Inventor： PAVLATH GEORGE A ,  MICHAL RONALD J ,  PATTERSON RALPH A ,  HUANG SIDNEY XI-YI

IPC: G01C19/72 ,  G01R33/032

Abstract: A fiber optic sensing coil formed in a polarization-maintaining optical fiber has two optical fiber leads extending therefrom. A multifunction integrated optics chip linearly polarizes optical signals input to the sensing coil. Fiber optic leads formed of polarization-maintaining optical fiber extend from the multifunction integrated optics chip. The fiber optic multifunction integrated optics chip leads are arranged such that the linear polarization of optical signals output from the multifunction integrated optics chip is directed along one of the principal axes of birefringence of each of the fiber optic multifunction integrated optics chip leads. Splices are formed between corresponding the first sensing coil leads and the multifunction integrated optics chip leads. The sensing coil leads and the multifunction integrated optics chip leads are arranged such that their corresponding principal axes of birefringence are at angles of approximately 45~ relative to one another. The first splice is formed a distance from the multifunction integrated optics chip such that a selected phase change between polarization components occurs in optical waves that propagate the distance L1 in the first multifunction integrated optics chip lead.

公开(公告)号：CA2105616A1

公开(公告)日：1994-08-13

申请号：CA2105616

申请日：1993-09-07

Applicant: LITTON SYSTEMS INC

Inventor： HUANG SIDNEY X ,  MICHAL RONALD J ,  PATTERSON RALPH A ,  PAVLATH GEORGE A

IPC: G01C19/72 ,  G02B6/00

Abstract: Apparatus for suppressing the bias errors induced by the Faraday effect in the output of a sensor coil exposed to a magnetic field. Arrangements are formed at two leads of the sensor coil for compensating the bias shifts. One of such arrangements comprises at least one loop of optical fiber for compensating the effect induced by the magnetic field component oriented transverse to the axis of the sensor coil while the other comprises at least one loop oriented at a predetermined pitch angle for compensating the effect induced by a magnetic field component along the axis. In each case, a predetermined degree of twist of a preselected fiber twist mode is imposed upon the compensator loop for creating a counteracting, corrective Faraday effect. Cross-coupling does not occur between the two compensators as their twist rate perodicities are unequal.