	US 12,259,296 B2
	Apparatus, method and system for detecting presence of a fluid
Cyril Hnatovsky, Ottawa (CA); Dan Grobnic, Ottawa (CA); Stephen Mihailov, Kanata (CA); Ping Lu, Stittsville (CA); Kasthuri De Silva, Milton (CA); Huimin Ding, Nepean (CA); David Coulas, Greely (CA); and Robert Walker, Spencerville (CA)
Assigned to NATIONAL RESEARCH COUNCIL OF CANADA, Ottawa (CA)
Appl. No. 17/432,709
Filed by NATIONAL RESEARCH COUNCIL OF CANADA, Ottawa (CA)
PCT Filed Jan. 10, 2020, PCT No. PCT/IB2020/050187 § 371(c)(1), (2) Date Aug. 20, 2021, PCT Pub. No. WO2020/170047, PCT Pub. Date Aug. 27, 2020.
Claims priority of provisional application 62/809,092, filed on Feb. 22, 2019.
Prior Publication US 2022/0196508 A1, Jun. 23, 2022
Int. Cl. G01M 3/04 (2006.01)

CPC G01M 3/04 (2013.01)

4 Claims

1. A method for detecting presence of a fluid, comprising:

mounting a sensor array proximate a conduit for said fluid, said sensor array comprising a plurality of Bragg grating sensing elements within an optical waveguide, each Bragg grating sensing element being encapsulated in a package for subjecting the Bragg grating sensing element to a change in strain when contacted by said fluid; and

interrogating said sensor array with laser light to detect any change in the optical properties of the Bragg grating sensing elements due to the change in strain, wherein said package encapsulates the Bragg grating sensing element under an initial strain and decreases the strain to which the Bragg grating sensing element is subjected when contacted by said fluid.