A method of making an optical fiber sensor device for distributed sensing includes generating a laser beam comprising a plurality of ultrafast pulses, and focusing the laser beam into a core of an optical fiber to form a nanograting structure within the core, wherein the nanograting structure includes a plurality of spaced nanograting elements each extending substantially parallel to a longitudinal axis of optical fiber. Also, an optical fiber sensor device for distributed sensing includes an optical fiber having a longitudinal axis, a core, and a nanograting structure within the core, wherein the nanograting structure includes a plurality of spaced nanograting elements each extending substantially parallel to the longitudinal axis of the optical fiber. Also, a distributed sensing method and system and an energy production system that employs such an optical fiber sensor device.

A mode loss difference compensator of the present disclosure includes a main waveguide configured to allow propagation of N or more modes (where N is an integer of 3 or more), a first auxiliary waveguide having, at one end thereof, a first coupling portion configured to mode-convert an LP0n mode (where n is an integer of 2 or more) propagating in the main waveguide into a fundamental mode in the first auxiliary waveguide and transfer the fundamental mode from the main waveguide to the first auxiliary waveguide and having, at the other end thereof, a second coupling portion configured to mode-convert the fundamental mode propagating in the first auxiliary waveguide into the LP0n mode (where n is an integer of 2 or more) in the main waveguide and transfer the LP0n mode from the first auxiliary waveguide to the main waveguide, and a second auxiliary waveguide having, at one end thereof, a third coupling portion configured to convert a higher-order mode, other than any LP0n mode (where n is an integer of 2 or more), propagating in the main waveguide into a fundamental mode in the second auxiliary waveguide and transfer the fundamental mode from the main waveguide to the second auxiliary waveguide and having, at the other end thereof, a terminal end portion configured to eliminate the fundamental mode propagating in the second auxiliary waveguide from the second auxiliary waveguide, wherein the main waveguide includes a loss imparting portion configured to impart a loss to a fundamental mode propagating in the main waveguide between the first and second coupling portions.

The exemplary embodiments provide an optical fiber sensor and a vector measuring device which measure a motion of a subject using a double Bragg grating formed in a core with a helical structure and measure a chiral motion inflection point vector.

A Bragg grating temperature sensor includes an optical fiber including a core, an optical cladding surrounding the core and a Bragg grating incorporated in the core and extending along a sensitive segment of the optical fiber. The core of the temperature sensor includes a core gap extending along a core gap segment of the optical fiber, the core gap segment being located in the vicinity of the sensitive segment. The optical cladding includes a cladding gap extending along a cladding gap segment of the optical fiber, the cladding gap segment including the sensitive segment.

A Bragg grating optical fiber sensor for measuring temperatures and deformations and a method for manufacturing same, the manufacturing method including ablating a mechanical coating over a portion of an optical fiber so as to form an opening extending radially over the entire thickness of the mechanical coating, and inscribing a Bragg grating into the optical fiber through the opening.

The present invention relates to an apparatus for optical applications, a spectrometer system and method for producing an apparatus for optical applications, and in particular to an apparatus comprising an optical waveguide having a first refractive index along a light propagation axis interrupted by a plurality of scattering portions having a second refractive index. Each scattering portion has a long axis substantially perpendicular to the light propagation axis as well as a short axis substantially perpendicular to the light propagation axis and the long axis. A receiver unit or a transmitter unit is arranged on a side of the optical waveguide, the long axis being substantially perpendicular, i.e. normal to the plane of this side on which the receiver unit or transmitter unit is arranged. Accordingly, simplification and miniaturization of an optical apparatus can be realized.

A peripheral light-emitting linear light guide member is composed of an optical fiber including a core having an outer periphery surface exposed from a cladding at one end in a longitudinal direction, and a light-scattering member covering an entire periphery of the outer periphery surface at an exposed portion of the core over a predetermined axial length range. The light-scattering member scatters a light emitted from the outer periphery surface of the core. In the light-scattering member, light-scattering particles are dispersion-mixed with an optically transparent base material having a higher refractive index than a refractive index of the core. An amount of the light-scattering particles around an outer periphery of the core is higher at a distal end of the light-scattering member than at an end closer to the cladding.

A laser delivery device may include a connector portion at a proximal end of the laser delivery device and an optical fiber connecting the connector portion to a distal end of the laser delivery device. The connector portion may include a capillary at least partially surrounding a proximal portion of the optical fiber, and the capillary may include dimples on at least a portion of a circumferential surface thereof.

The present invention relates to an apparatus for optical applications, a spectrometer system and method for producing an apparatus for optical applications, and in particular to an apparatus comprising an optical waveguide having a first refractive index along a light propagation axis interrupted by a plurality of scattering portions having a second refractive index. Each scattering portion has a long axis substantially perpendicular to the light propagation axis as well as a short axis substantially perpendicular to the light propagation axis and the long axis. A receiver unit or a transmitter unit is arranged on a side of the optical waveguide, the long axis being substantially perpendicular, i.e. normal to the plane of this side on which the receiver unit or transmitter unit is arranged. Accordingly, simplification and miniaturization of an optical apparatus can be realized.

A manufacturing device of an optical fiber grating to write a grating in a core of an optical fiber by irradiating the optical fiber with laser light includes: a fixing device that fixes the optical fiber to at least one of a first position located more on an upstream side and a second position located more on a downstream side in a conveyance direction of the optical fiber than a laser light irradiating position of the optical fiber in a case of writing the grating; and a feeder having a structure capable of linearly reciprocating in the conveyance direction and adapted to feed a predetermined length of the optical fiber in the conveyance direction in a case where a fixed state of the optical fiber by the fixing device is released.