A temperature sensor and temperature sensing system for sensing changes m temperature up to a predetermined temperature is disclosed. The temperature sensor includes a microstructured optical fiber where the micro-structured optical fiber includes a plurality of longitudinal channels extending along the microstructured optical fiber. The sensor also includes a fiber Bragg grating formed in the microstructured optical, fiber by generating a periodic modulation in the refractive index along a core region of the microstructured optical fiber. The fiber Bragg grating is operable to produce band reflection at a reflection wavelength that varies in accordance with changes in temperature at the core region of the optical fiber.

The invention relates to installations for fibre optic monitoring of articles, and apparatus and methods for forming such installations, including a modular system and components for forming a fibre optic monitoring installation. Applications of the invention include the monitoring of vessels, chambers, and fluid conduits in industrial processing plants, and the invention has particular application to monitoring large vessels, for example temperature monitoring of vessels used in catalytic reforming processes. Convenient installation on or removal from the article being monitored is achieved by providing a support structure for the fibre optic length, which presents the fibre optic length in a preconfigured orientation suitable for monitoring the article. In a particular embodiment of the invention, the fibre optic length is disposed on a panel in a plurality of dense spiral patterns.

The invention relates to installations for fibre optic monitoring of articles, and apparatus and methods for forming such installations, including a modular system and components for forming a fibre optic monitoring installation. Applications of the invention include the monitoring of vessels, chambers, and fluid conduits in industrial processing plants, and the invention has particular application to monitoring large vessels, for example temperature monitoring of vessels used in catalytic reforming processes. Convenient installation on or removal from the article being monitored is achieved by providing a support structure for the fibre optic length, which presents the fibre optic length in a preconfigured orientation suitable for monitoring the article. In a particular embodiment of the invention, the fibre optic length is disposed on a panel in a plurality of dense spiral patterns.

A light interference system is provided. The light interference system includes a light source configured to generate a measurement light; a fiber configured to propagate therethrough the measurement light; and a measurement device. The fiber includes a single-mode fiber, a multimode fiber and a connector connecting the single-mode fiber and the multimode fiber. A tip end of the fiber is formed of the multimode fiber, and an end surface of the tip end of the fiber is configured to emit the measurement light to a measurement target object and receive a reflection light from the measurement target object. The measurement device is configured to measure physical property of the measurement target object based on the reflection light.

The present invention relates to a system, method and computer-program for evaluating the photoluminescence of a photonic marker as well as to a photonic marker for temperature sensing and/or security marking and to the use of the photonic marker for temperature sensing and/or security marking. The photonic marker according to an aspect of the present invention comprises a host material selected from the group consisting of a rare earth element oxysulfide and strontium aluminate, wherein the host material is doped with Eu.sup.3+ or Eu.sup.2+ as a dopant.

The present invention relates to a system, method and computer-program for evaluating the photoluminescence of a photonic marker as well as to a photonic marker for temperature sensing and/or security marking and to the use of the photonic marker for temperature sensing and/or security marking. The photonic marker according to an aspect of the present invention comprises a host material selected from the group consisting of a rare earth element oxysulfide and strontium aluminate, wherein the host material is doped with Eu.sup.3+ or Eu.sup.2+ as a dopant.

Distributed fiber optic sensing systems (DFOS) methods, and structures that employ DVS / DAS point sensors and a two-stage processing methodology / structure that advantageously enable point sensors to send sensor data at any time - thereby providing significant processing advantages over the prior art.

Distributed fiber optic sensing systems (DFOS) methods, and structures that employ DVS / DAS point sensors and a two-stage processing methodology / structure that advantageously enable point sensors to send sensor data at any time - thereby providing significant processing advantages over the prior art.

In some examples, a temperature distribution sensor may include a laser source to emit a laser beam that is tunable over a wavelength range. The wavelength range may be less than a Raman bandwidth in a device under test (DUT), or of-the-order-of the Raman bandwidth in the DUT. A pulsed source may apply a pulse drive signal to the laser beam or to a modulator to modulate the laser beam that is to be injected into the DUT. A bandpass filter may be operatively disposed between the laser source and the DUT, and may be configured to an anti-Stokes wavelength that is narrower than the Raman bandwidth. A photodiode may be operatively disposed between the bandpass filter and the DUT to acquire, from the DUT, anti-Stokes optical time-domain reflectometer traces for two preset wavelengths of the laser beam to determine a temperature distribution for the DUT.

In some examples, a temperature distribution sensor may include a laser source to emit a laser beam that is tunable over a wavelength range. The wavelength range may be less than a Raman bandwidth in a device under test (DUT), or of-the-order-of the Raman bandwidth in the DUT. A pulsed source may apply a pulse drive signal to the laser beam or to a modulator to modulate the laser beam that is to be injected into the DUT. A bandpass filter may be operatively disposed between the laser source and the DUT, and may be configured to an anti-Stokes wavelength that is narrower than the Raman bandwidth. A photodiode may be operatively disposed between the bandpass filter and the DUT to acquire, from the DUT, anti-Stokes optical time-domain reflectometer traces for two preset wavelengths of the laser beam to determine a temperature distribution for the DUT.