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Patent Searching and Data


Title:
ブラッグ回折格子圧力センサ
Document Type and Number:
Japanese Patent JP2004506869
Kind Code:
A
Abstract:
A fiber grating pressure sensor includes an optical sensing element 20, 600 which includes an optical fiber 10 having a Bragg grating 12 impressed therein which is encased within and fused to at least a portion of a glass capillary tube 20 and/or a large diameter waveguide grating 600 having a core and a wide cladding and which has an outer transverse dimension of at least 0.3 mm. Light 14 is incident on the grating 12 and light 16 is reflected from the grating 12 at a reflection wavelength lambd1. The sensing element 20, 600 may be used by itself as a sensor or located within a housing 48, 60, 90, 270, 300. When external pressure P increases, the grating 12 is compressed and the reflection wavelength lambd1 changes. The shape of the sensing element 20, 600 may have other geometries, e.g., a "dogbone" shape, so as to enhance the sensitivity of shift in lambd1 due to applied external pressure and may be fused to an outer shell 50. At least a portion of the sensing element may be doped between a pair of gratings 150, 152, to form a compression-tuned laser or the grating 12 or gratings 150, 152 may be constructed as a tunable DFB laser. Also, the axial ends of element 20, 600 where the fiber 10 exits the tube 20 may have an inner tapered region 22 and/or a protruding tapered (or fluted) axial section 27 to provide strain relief or improved pull strength for the fiber 10. A temperature grating 270 may be used to measure temperature and allow for a temperature-corrected pressure measurement. The sensor may be suspended within an outer housing 112, by a fluid, spacers, or other means. The invention may also be used as a force transducer.

Inventors:
Fernardo, Mark Earl.
Byray, Timothy Jay.
Mirror, Matthew Bee.
Sullivan, James M.
Dunphy, James Earl.
Davis, Michael A.
Kelsey, Arandy.
Wright, Christopher Jay.
Putnan, Martin A.
Burkato, Robert N.
Sanders, Paul Yi.
Application Number:
JP2000589924A
Publication Date:
March 04, 2004
Filing Date:
December 06, 1999
Export Citation:
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Assignee:
Weatherford/Rum Incorporated
International Classes:
G01L1/24; G01J3/18; G01L11/00; G01L11/02; G02B5/18; G02B6/00; G02B6/02; (IPC1-7): G01L1/24; G01L11/02; G02B5/18; G02B6/00; G02B6/10
Domestic Patent References:
JPS61502980A1986-12-18
JPH05503170A1993-05-27
Foreign References:
WO1998031987A11998-07-23
WO1995030926A11995-11-16
US5844667A1998-12-01
US5612778A1997-03-18
US4932263A1990-06-12
DE19648403C11998-04-02
GB2299203A1996-09-25
WO1998017968A11998-04-30
US5757540A1998-05-26
US5745626A1998-04-28
US5113070A1992-05-12
Attorney, Agent or Firm:
Fujiya Shiga
Tsuyoshi Hashimoto
Tomioka Kiyoshi