公开(公告)号：GR3032556T3

公开(公告)日：2000-05-31

申请号：GR20000400252

申请日：2000-02-02

Applicant: UNITED TECHNOLOGIES CORP ,  FINMECCANICA SPA

Inventor： MELTZ GERALD ,  VARASI MAURO ,  VANNUCCI ANTONELLO ,  SIGNORAZZI MARIO ,  FERRARO PIETRO ,  IMPARATO SABATO INSERRA ,  VOTO CLAUDIO ,  DUNPHY JAMES R

IPC: G01B11/16 ,  G01D21/02 ,  G01K5/72 ,  G01L1/24 ,  G01K11/12 ,  G01K11/32 ,  G01M11/08 ,  G01D5/353 ,  G01D5/34 ,  G01D5/26

Abstract: An embedded optical sensor has a plurality of layers 10-20 and an optical fiber 21 with a fiber grating 28, disposed between the layers 14,16. The layers 10-20 comprise filaments 22 and resin 24 which have different thermal expansion coefficients and the filaments 22 are oriented so as to create unequal transverse residual stresses that act through the geometry of a resin-rich region that surrounds on the grating 28 in the fiber 21. The unequal transverse residual stresses cause birefringence in the grating 28, thereby causing the grating 28 to reflect light 32 having two wavelengths with a predetermined separation, each along a different polarization axis. The wavelength separation and average wavelength between such separation have different sensitivities to temperature and strain, thereby allowing independent temperature and strain measurements using only a single grating. The birefringence is maximized when the filaments 22 of the adjacent layers 10,12 are oriented at 90 degrees with respect to the longitudinal (Z-axis) of the fiber 21.

公开(公告)号：DK0753130T3

公开(公告)日：2000-04-25

申请号：DK95913985

申请日：1995-03-08

Applicant: UNITED TECHNOLOGIES CORP

Inventor： MELTZ GERALD ,  VARASI MAURO ,  VANNUCCI ANTONELLO ,  SIGNORAZZI MARIO ,  FERRARO PIETRO ,  IMPARATO SABATO INSERRA ,  VOTO CLAUDIO ,  DUNPHY JAMES R

IPC: G01L1/24 ,  G01B11/16 ,  G01D21/02 ,  G01K5/72 ,  G01K11/12 ,  G01K11/32 ,  G01M11/08 ,  G01D5/353 ,  G01D5/26 ,  G01D5/34

Abstract: An embedded optical sensor has a plurality of layers 10-20 and an optical fiber 21 with a fiber grating 28, disposed between the layers 14,16. The layers 10-20 comprise filaments 22 and resin 24 which have different thermal expansion coefficients and the filaments 22 are oriented so as to create unequal transverse residual stresses that act through the geometry of a resin-rich region that surrounds on the grating 28 in the fiber 21. The unequal transverse residual stresses cause birefringence in the grating 28, thereby causing the grating 28 to reflect light 32 having two wavelengths with a predetermined separation, each along a different polarization axis. The wavelength separation and average wavelength between such separation have different sensitivities to temperature and strain, thereby allowing independent temperature and strain measurements using only a single grating. The birefringence is maximized when the filaments 22 of the adjacent layers 10,12 are oriented at 90 degrees with respect to the longitudinal (Z-axis) of the fiber 21.