公开(公告)号：US12259296B2

公开(公告)日：2025-03-25

申请号：US17432709

申请日：2020-01-10

Applicant: NATIONAL RESEARCH COUNCIL OF CANADA

Inventor： Cyril Hnatovsky ,  Dan Grobnic ,  Stephen Mihailov ,  Ping Lu ,  Kasthuri De Silva ,  Huimin Ding ,  David Coulas ,  Robert Walker

IPC: G01M3/04

Abstract: An apparatus, method and system are set forth for detection of fluids using Bragg grating sensors, wherein the Bragg grating sensing element comprises an optical fiber having a Bragg grating inscribed therein characterized by optical properties that are dependent upon the periodicity and effective refractive index of the grating, and a package for subjecting the Bragg grating to a change in strain when contacted by a fluid such that periodicity and effective refractive index of the grating changes, whereby when interrogated with laser light any such change in periodicity and effective refractive index may be detected.

公开(公告)号：US12164144B2

公开(公告)日：2024-12-10

申请号：US17924434

申请日：2020-05-13

Applicant: NATIONAL RESEARCH COUNCIL OF CANADA

Inventor： Cyril Hnatovsky ,  Nurmemet Abdukerim ,  Dan Grobnic ,  Stephen Mihailov ,  Rune Lausten ,  Ping Lu ,  Huimin Ding ,  David Coulas ,  Kasthuri De Silva

IPC: G02B6/02 ,  G02B5/18

Abstract: A method and apparatus for inscribing a Bragg grating in an optical waveguide, comprising: providing electromagnetic radiation from an ultrashort pulse duration laser, wherein the electromagnetic radiation has a pulse duration of less than or equal to 5 picoseconds, and wherein the wavelength of the electromagnetic radiation has a characteristic wavelength in the wavelength range from 150 nanometers (nm) to 2.0 microns (μm): providing cylindrical focusing optics corrected for spherical aberration: providing a diffractive optical element that when exposed to the focused ultrashort laser pulse, creates an interference pattern on the optical waveguide, wherein the irradiation step comprises irradiating a surface of the diffractive optical element with the focused electromagnetic radiation, the electromagnetic radiation incident on the optical waveguide, from the diffractive optical element, being sufficiently intense to cause the permanent change in the index of refraction in the core of the optical waveguide.