公开(公告)号：US11965732B2

公开(公告)日：2024-04-23

申请号：US17177785

申请日：2021-02-17

Applicant: University of Southampton

Inventor： Christopher Holmes ,  Janice Barton ,  Daniel Bull

IPC: G01B11/16 ,  G02B6/124 ,  G02B6/13 ,  G02B6/12

CPC classification number: G01B11/168 ,  G01B11/165 ,  G02B6/124 ,  G02B6/13 ,  G02B2006/12107 ,  G02B2006/12138

Abstract: A method of measuring strain includes providing laminated material having ply layers, and a thickness along a direction orthogonal to the ply layers, and a strain sensor embedded between adjacent ply layers, wherein: the strain sensor includes first and second planar optical waveguide, each of the waveguides having a waveguiding core defining an optical propagation direction parallel to the laminated material and a Bragg grating in the waveguiding core, the optical propagation directions of the optical waveguides being non-parallel; interrogating the first optical waveguide Bragg grating with transverse electric (TE) and transverse magnetic (TM) polarized light, to obtain a TE spectral response and a TM spectral response; interrogating the second optical waveguide Bragg grating with TE and TM polarized light to obtain a TE spectral response and a TM spectral response; and processing the TE spectral responses and the TM spectral responses to extract a through-thickness component of strain.