Various embodiments may provide an optical fiber for sensing an analyte. The optical fiber may include a dielectric core wall defining a hollow space. The optical fiber may also include a cladding layer surrounding the dielectric core wall and spaced apart from the dielectric core wall. The optical fiber may further include a plurality of supports extending from the cladding layer to the dielectric core wall. A thickness of the dielectric core wall may be greater than a thickness of each of the plurality of supports. The dielectric core wall may be configured to carry an optical light for sensing the analyte.

A fiber-optic salinity and temperature measurement includes a first Fabry-Perot interferometer and a second Fabry-Perot interferometer. Each of the Fabry-Perot interferometers includes a first optical fiber fusion spliced to a second optical fiber such that a relatively large cavity is formed between the fibers. The relatively large cavity forms the measurement chamber for each Fabry-Perot interferometer. The input port on each of the Fabry-Perot interferometers is coupled to an optical splitter such that a single optical signal input is provided to each Fabry-Perot interferometer. The output port on each of the Fabry-Perot interferometers is coupled to an optical combiner that combines the interference signal received from each of the Fabry-Perot interferometers. An optical signal analyzer coupled to an output port of the optical combiner determines the salinity and temperature of a sample material in the large cavity of the second Fabry-Perot interferometer.

Disclosed herein are Raman spectrographic systems and methods of assembling Raman spectrographic systems. The Raman spectrographic system includes a light source to emit ultraviolet incident light into a waveguide, and an interaction region traversed by the waveguide and that holds a sample to be identified. A spectrometer detects Raman scatter from an output light in the waveguide emerging from the interaction region following interaction between the incident light and the sample and output a spectral response. The spectrometer includes an array of detectors. Each detector of the array of detectors is a silicon carbide (SiC) detector to obtain information that includes an intensity corresponding with a wavelength of the Raman scatter. A controller identifies the sample based on the spectral response from the array of detectors.

A fiber optic temperature probe is disclosed. The fiber optic temperature probe includes a probe shaft containing an optical fiber. An optical temperature sensor element is coupled to the probe shaft and configured to be excited by light from the optical fiber and emit light back to the optical fiber. A thermally conductive plate is coupled to the probe shaft and interfaces with the optical temperature sensor element. Baffling extends from the probe shaft and surrounds the edges of the thermally conductive plate.

In a sensor device, a plurality of light guides having a respective first end and a respective second end are arranged on a common carrier, with the first end of each light guide of the plurality of light guides at a respective defined position on the carrier. At each of the second ends of the light guides there is provided at least one sensor element which exhibits an optical behavior dependent on an analyte. The second ends are at defined perpendicular distances to the carrier. At least two of the second ends differ with respect to the defined perpendicular distances.

A method of making an optical fiber-based sensor includes providing an optical fiber, and providing a sensing or protection layer on a surface of the optical fiber by an atomic layer deposition (ALD) process.

One or more embodiments relate to a sensor configuration system comprising at least one device configured to sense a first parameter; at least one device configured to sense a second parameter, and at least one interrogator device. The at least one device configured to sense the second parameter interfaces with the at least one device configured to sense the first parameter, and the at least one interrogator device interfaces both the at least one device configured to sense the first parameter and the at least one device configured to sense the second parameter where the at least one interrogator device spatially interrogates both the at least one device configured to sense the first parameter and the at least one device configured to sense the second parameter.

A method and device for monitoring oil field operations with a fiber optic distributed acoustic sensor (DAS) that uses a continuous wave laser light source and modulates the continuous wave output of the laser light source with pseudo-random binary sequence codes.

Provided is a spectroscopic analysis apparatus including: an optical probe; and a spectroscopic analysis portion to which the optical probe is attached. The optical probe includes an optical fiber that guides illumination light coming from a light source and signal light coming from an observation target and an optical member that is disposed at least at a distal end of the optical fiber. The spectroscopic analysis portion includes an information separation portion that generates wavelength dependent characteristics by optically dispersing the signal light and that separates, from information about the signal light, information about first return light returning from the optical member and information about second return light returning from the optical fiber, a problem determining portion that determines a problem occurring at the optical probe based on the separated first return light and second return light, and a notification portion that notifies information about the determined problem.

A pH photothermal spectrometer includes a container that receives an analyte medium and pH-sensitive chromophore. An excitation fiber and optical thermometer are disposed in the container. The optical thermometer include a light receiver disposed on a temperature detector fiber.