In various embodiments, wavelength beam combining laser systems incorporate optical cross-coupling mitigation systems and/or engineered partially reflective output couplers in order to reduce or substantially eliminate unwanted back-reflection of stray light.

A temperature sensor and temperature sensing system for sensing changes in temperature up to a predetermined temperature is disclosed. The temperature sensor includes a microstructured optical fiber where the microstructured 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 disclosed embodiments generally relate to extruding multiple layers of micro- to nano-polymer layers in a tubular shape. In particular, the aspects of the disclosed embodiments are directed to a method for producing a Bragg reflector comprising co-extrusion of micro- to nano-polymer layers in a tubular shape.

An apparatuses relating generally to a test wafer, processing chambers, and method relating generally to monitoring or calibrating a processing chamber, are described. In one such an apparatus for a test wafer, there is a platform. An optical fiber with Fiber Bragg Grating sensors is located over the platform. A layer of material is located over the platform and over the optical fiber.

A method for determining a curvature and/or torsion of an optical waveguide of a fibre-optic sensor, comprising at least two Bragg gratings introduced into the optical waveguide and extending through a common cross-sectional plane, situated in a radial direction, through the optical waveguide, wherein the Bragg gratings are introduced in the core and/or on the boundary between the core and the cladding and/or in an inner edge region of the cladding within an evanescence region of the light, the method comprising: providing reference data of intensities of reflected light portions of light coupled into the optical waveguide, in particular depending on known reference deformations of the optical waveguide, measuring at least one light intensity of reflected light portions of light coupled into the optical waveguide, wherein the optical waveguide has a deformation to be determined, and determining the deformation by comparing the light intensity with the reference data.

Fiber Bragg grating interrogation and sensing used for strain and temperature measurements. A simple, broadband light source is used to interrogate one or more fiber Bragg grating (FBG). Specifically, a packaged LED is coupled to fiber, the light therefrom is reflected off a uniform FBG. The reflected light is subsequently analyzed using a filter and a plurality of Si photodetectors. In particular, the filter is a chirped FBG or an optically coated filter, in accordance with some embodiments. Measurement analysis is performed by ratio of intensities at the plurality of detectors, at least in part.

An optical system adapted to detect an object including a beam splitting and combing element, a catheter, a focusing element, a deformation detecting module, and an object detecting module is provided. The catheter sleeves outside an optical fiber, and the optical fiber has at least one fiber Bragg gratings. The deformation detecting module and the object detecting module are coupled to the beam splitting and combing element. A first light is reflected by the at least one fiber Bragg gratings and then transmitted to the deformation detecting module. A second light is transmitted to and reflected by the object, so as to be transmitted to the object detecting module. A first wavelength range of the first light is different from a second wavelength range of the second light.

An apparatuses relating generally to a test wafer, processing chambers, and method relating generally to monitoring or calibrating a processing chamber, are described. In one such an apparatus for a test wafer, there is a platform. An optical fiber with Fiber Bragg Grating sensors is located over the platform. A layer of material is located over the platform and over the optical fiber.

A system and method for detecting dynamic strain of a housing. The system includes an optical fiber linearly affixed along a surface of a length of the housing and an interrogator comprising a laser source and a photodetector. The optical fiber comprises at least one pair of fiber Bragg gratings (FBGs) tuned to reflect substantially identical wavelengths with a segment of the optical fiber extending between the FBGs. The segment of the optical fiber is linearly affixed along the surface of the housing. The interrogator is configured to perform interferometry by shining laser light along the optical fiber and detecting light reflected by the FBGs. The interrogator outputs dynamic strain measurements based on interferometry performed on the reflected light.

A multi-channel receiver optical sub assembly module for a fiber Bragg grating sensor according to an embodiment of the present invention includes a housing, a connection socket, an optical bench, a thermoelectric cooler, an arrayed waveguide grating chip, a photodiode array disposed on the optical bench and including a plurality of photodiode chips connected to the optical channels of the arrayed waveguide grating chip, and a printed circuit board which is connected to the other side of the housing while passing through the other side of the housing, of which a portion of a body is disposed on the optical bench, and which is connected to the photodiode array.