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.

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.

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 fiber optic light source in which input light with short and narrow band wavelength is converted/transformed into multi-band visible white light with high intensity output power is provided. The new light source comprises at least one homogenizing light guide element, and at least one photoluminescence element. It may also comprise at least one input element and an optical fiber. All or some of the elements may be integrated into an optical waveguide. In some embodiments, the at least one input element increases light transfer efficiency from a ray source to the at least one homogenizing light guide element component of the fiber optic light source. The at least one photoluminescence element can be a point or an extended form like a line or surface. The fiber optic light source output beam may also contain the input ray wavelength, which in turn can be from a fiber optic laser. In operation, an input ray travels through at least one homogenizing light guide element and irradiates at least one photoluminescence element present in preselected positions of the device to cause large area or spacious illumination at a desired target. This source can be an information source to communicate information through light modulation not noticeable to the naked human eye. Information is sent from the optical light source to information receivers, technical devices like smart phones, TV-Displays, or other devices, which could replace the common use of LAN or WLAN networks. Here a known luminescent detector can be used to efficiently collect the information in its optical form and to lead it to a suitable photo detector. This enables free-space optical light information transfer especially in areas where traditional infrastructure using transmitting fibers is difficult to establish.

Method for creating an optical sensing fiber having a reflective structure integrally disposed therein, comprising: providing an optical fiber having a core and a cladding layer disposed in optical contact with the core, and having a polymer coating layer disposed in contact with and surrounding the cladding layer, the coating layer at least partially transparent in the wavelengths of 390-600 nm; providing a source of electromagnetic radiation having a wavelength in the range of 390-600 nm; and delivering a selected wavelength of the electromagnetic radiation through the coating layer to a selected location within the fiber core or cladding such that the delivered electromagnetic radiation alters the core or cladding to create at least one reflective structure in the core or cladding at the selected location.

A bending detecting system includes a light guide, a first grating and a light detector. The light guide has elongated shape and is configured to guide an incident light in a propagating direction. The light guide includes a core and a cladding disposed around the core. The first grating is disposed in a boundary area, the boundary area including an outer surface of the core, and an adjacent area that is adjacent to the outer surface. The first grating includes a first periodic structure along the propagating direction with a first pitch, and is configured to generate a first diffracted light from the incident light. The light detector is configured to detect the first diffracted light from the first grating, and detect a bending of the light guide based upon an optical feature amount of the first diffracted light.

An optoelectronic device (20, 50) includes a planar substrate (30), an optical bus (40, 82, 84, 96, 140, 150, 180, 182, 224) disposed on the substrate and configured to convey coherent radiation through the bus, and an array (32, 72) of sensing cells (34, 74, 90, 160, 170, 200, 212, 380) disposed on the substrate. Each sensing cell includes at least one tap (92, 94, 144, 146, 226, 228) coupled to extract a portion of the coherent radiation propagating through the optical bus, an optical transducer (36, 108, 162, 172, 202, 204, 214) configured to couple optical radiation between the sensing cell and a target external to the substrate, and a receiver (114, 174, 178, 216, 218), which is coupled to mix the coherent radiation extracted by the tap with the optical radiation received by the optical transducer and to output an electrical signal responsively to the mixed radiation.

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.

An optical fiber made of silica glass includes a core having a maximum refractive index n1, a depressed portion surrounding the core and having an average refractive index n2, and cladding surrounding the depressed portion and having an average refractive index n3. In the optical fiber, n1>n3>n2. The optical fiber has a local maximum value of chromatic dispersion within a wavelength range of 1530 nm to 1610 nm, and the local maximum value is 2 ps/nm/km or greater and below 0 ps/nm/km. (86 words)

A high backscattering optical fiber comprising a perturbed segment in which the perturbed segment reflects a relative power such that the optical fiber has an effective index of n.sub.eff, a numerical aperture of NA, a scatter of R.sub.p.fwdarw.r.sup.(fiber) that varies axially along the optical fiber, a total transmission loss of ?.sub.fiber, an in-band range greater than one nanometer (1 nm), and a figure of merit (FOM) in the in-band range. The FOM being defined as: $FOM=\frac{R_{p.fwdarw.r}^{\left(\mathrm{fiber}\right)}}{{{?}_{\mathrm{fiber}}\left(\frac{\mathrm{NA}}{2n_{\mathrm{eff}}}\right)}^2}.$