A lightweight stacked optical waveguide using two plastic substrates having nano-structure gratings and a single glass substrate sandwiched between them. The nano-structure gratings face each other, and are each encapsulated within the optical waveguide. The two plastic substrates are each adhesively secured to the central glass substrate rather than to each other to provide sufficient securing strength and precisely establish and maintain an air gap between the substrates. The thickness of the plastic substrates and the glass substrate are selected such that the stacked optical waveguide is lightweight, but also has sufficient drop performance. The stacked optical waveguide can be efficiently manufactured as the adhesive bonds a plastic substrate to a glass substrate.

A weldable strain sensor includes a strain sensor having two end portions in signal communication with signal lines for transmitting a measurement signal. A sensor carrier extends in a direction of the strain sensor and is firmly connected to the strain sensor. The sensor carrier includes two end portions having slots to thereby form tongues defining tongue ends which are directed in opposition to each other. Integrally surrounding the strain sensor and the end portions thereof is a protective cover of solid plastic which is firmly connected to the sensor carrier. The protective cover is configured in a region of the strain sensor narrow and flat and in a region of coupling points of the strain sensor with the signal lines at least twice as wide and at least twice as high as in a region of the strain sensor.

A fabrication method of a multi-core fiber Bragg grating (FBG) probe for measuring structures of a micro part based on the capillary self-assembly technique, wherein the diameter of the fiber (6) inscribed with FBG is reduced using a mechanical method or an etch method by the hydrofluoric acid; the fibers (6) inscribed with FBG, whose diameter has been reduced, are inserted into a tube (7) through its terminal with an inner taper angle; the FBG terminals of these fibers (6) are immersed into the UV adhesive (10) of a low viscosity and the UV adhesive (10) is raised in the gaps between the fibers (6); or the UV adhesive is dropped on these fibers (6) and the capillary bridge between the fibers (6) is formed; a most compact structure of the fiber bundle is formed as a result of the capillary self-assembly; the fiber bundle is cured using a UV light and the multi-core FBG (11) is therefore formed; the terminal of the multi-core FBG (11) is polished with an optic fiber polishing machine and then a spherical tip is fabricated with the melting fiber method or the installation method of a micro ball; therefore, a multi-core FBG (11) probe can be achieved. The method features low crosstalk between signal of FBG, inexpensive and low insertion loss.

A device and system for detecting dynamic strain. The device comprises a longitudinally extending carrier and an optical fiber embedded along an outer surface of a length of the carrier. The optical fiber comprises at least one pair of fiber Bragg gratings (FBGs) tuned to reflect substantially identical wavelengths. The system comprises the device and an interrogator comprising a laser source and a photodetector. 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 device and system for detecting dynamic strain. The device comprises a longitudinally extending carrier and an optical fiber embedded along an outer surface of a length of the carrier. The optical fiber comprises at least one pair of fiber Bragg gratings (FBGs) tuned to reflect substantially identical wavelengths. The system comprises the device and an interrogator comprising a laser source and a photodetector. 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.

An optical emitter package is disclosed. The optical emitter package can include a carrier, a switching die, and an optical emitter die mounted to the carrier. The optical emitter die can be directly electrically and mechanically connected to the carrier with a conductive adhesive. An energy storage device can be mounted to the carrier. The energy storage device can be directly electrically and mechanically connected to the carrier with a second conductive adhesive. The carrier can provide electrical communication between the switching die, the optical emitter die, and the energy storage device.

Assemblies, optical connectors, and methods for forming fiber arrays using laser bonded optical fibers are disclosed. In one embodiment, a method of forming a fiber array includes placing an optical fiber on a surface of a substrate, directing a laser beam into the optical fiber disposed on the surface of the substrate, melting, using the laser beam, a material of the substrate to create a first laser bond zone between the optical fiber and the surface of the substrate, applying an adhesive to the optical fiber and the substrate to create an adhesive bond zone between the optical fiber and the surface of the substrate, and cutting the optical fiber and the substrate to create a first section of the fiber array and a second section of the fiber array. The first section of the fiber array includes a first portion of the optical fiber, a first portion of the substrate, a first portion of the adhesive bond zone, and the first laser bond zone, and the second section of the fiber array includes a second portion of the optical fiber, a second portion of the substrate, and a second portion of the adhesive bond zone.

A FBG strain sensor arrangement includes a sensor carrier of steel sheet to which a FBG strain sensor is fastened. The FBG strain sensor includes an optical fiber having two end portions, with a Bragg grating provided between the end portions. An optical signal line is coupled to each end portion for transmission of a measurement signal. A protective cover has a first part configured thin and narrow and bonded to the sensor carrier along the optical fiber so that the optical fiber lying underneath is fixed with the Bragg grating on the sensor carrier. The protective cover is enlarged at each end portion of the optical fiber to thereby form a cavity underneath, with edges of the enlarged second part of the protective cover being bonded to the sensor carrier. Arranged in the cavity is an elastic filler which embeds the coupling points in a vibration damping manner.

Assemblies, optical connectors, and methods for bonding optical fibers to a substrate using a laser beam are disclosed. In one embodiment, a method of bonding an optical fiber to a substrate includes directing a laser beam into the optical fiber disposed on a surface of the substrate, wherein the optical fiber has a curved surface and the curved surface of the optical fiber focuses the laser beam to a diameter that is smaller than a diameter of the laser beam as it enters the optical fiber. The method further includes melting, using the laser beam, a material of the substrate at a bond area between the optical fiber and the surface of the substrate such that the optical fiber is bonded to the surface of the substrate.

Assemblies, optical connectors, and methods for forming fiber arrays using laser bonded optical fibers are disclosed. In one embodiment, a method of forming a fiber array includes placing an optical fiber on a surface of a substrate, directing a laser beam into the optical fiber disposed on the surface of the substrate, melting, using the laser beam, a material of the substrate to create a first laser bond zone between the optical fiber and the surface of the substrate, applying an adhesive to the optical fiber and the substrate to create an adhesive bond zone between the optical fiber and the surface of the substrate, and cutting the optical fiber and the substrate to create a first section of the fiber array and a second section of the fiber array. The first section of the fiber array includes a first portion of the optical fiber, a first portion of the substrate, a first portion of the adhesive bond zone, and the first laser bond zone, and the second section of the fiber array includes a second portion of the optical fiber, a second portion of the substrate, and a second portion of the adhesive bond zone.