Abstract: A measurement device including an etalon, the reflection power spectrum of which includes multiple power peaks distributed within a working range, the free spectral range of the etalon being less than or equal to 5 nm. The etalon including a waveguide, and a Bragg grating formed in the waveguide, the Bragg grating including at least three identical patterns aligned one behind the other along a longitudinal axis of the waveguide and separated from one another by a constant spacing. The spacing of the Bragg grating is configured for the power spectrum of the grating to have multiple discernible harmonics with an order greater than one hundred in the working range, these harmonics thus forming the power peaks of the power spectrum of the etalon.

Abstract: The field of integrated health monitoring using Bragg grating optical fibre sensors including a sensor and methods for locating and installing this sensor on a support. The Bragg grating optical fibre sensor includes an optical fibre wherein at least one set of patterns forming a Bragg grating is written, the optical fibre further including a set of microstructures in the vicinity of each Bragg grating, the microstructures being separate from the patterns forming the Bragg grating, each microstructure being capable of scattering a portion of a light beam within a predetermined range of scattering wavelengths.

Abstract: An erosion sensor includes one or more optical fibres each having one or more cores and an optical sheath surrounding the one or more cores, a variable pitch measurement Bragg grating inscribed in one of the cores of one of the optical fibres over a measurement section to be eroded, and one or more reference Bragg gratings each inscribed in one of the cores. The reference Bragg grating is used to correct the physical length of the measurement section determined from the width of the spectrum reflected by the measurement Bragg grating, taking into account the thermomechanical parameters imposed on the erosion sensor.

Abstract: A Bragg grating temperature sensor includes an optical fiber including a core, an optical cladding surrounding the core and a Bragg grating incorporated in the core and extending along a sensitive segment of the optical fiber. The core of the temperature sensor includes a core gap extending along a core gap segment of the optical fiber, the core gap segment being located in the vicinity of the sensitive segment. The optical cladding includes a cladding gap extending along a cladding gap segment of the optical fiber, the cladding gap segment including the sensitive segment.

Abstract: The field of integrated health monitoring using Bragg grating optical fibre sensors including a sensor and methods for locating and installing this sensor on a support. The Bragg grating optical fibre sensor includes an optical fibre wherein at least one set of patterns forming a Bragg grating is written, the optical fibre further including a set of microstructures in the vicinity of each Bragg grating, the microstructures being separate from the patterns forming the Bragg grating, each microstructure being capable of scattering a portion of a light beam within a predetermined range of scattering wavelengths.