An apparatus for heat deposition in additive manufacturing may include: a first optical beam source configured to generate a first optical beam; a second optical beam source configured to generate a second optical beam; and/or an optical system. The optical system may be configured to move the generated first optical beam over a target area. The optical system may be further configured to move the generated second optical beam over the target area so that a path of the second optical beam moving over the target area is dithered about a path of the first optical beam moving over the target area. The optical system may be configured to focus the generated first optical beam at a plane of a target area. The optical system may be further configured to focus the generated second optical beam at the plane of the target area.

According to one implementation an assembly is provided that facilitates a coupling of one or more light diffusing optical fibers to one or more light emitting diodes. According to one implementation the assembly includes a light emitting diode positioned inside a cavity of a frame that is equipped with means to directly or indirectly electrically couple the anode and cathode of the light emitting diode to a printed circuit board. A proximal end portion of the light diffusing optical fiber is supported inside a through opening of a lid positioned over a front side of the frame. The light diffusing optical fiber includes a core that is surround by a cladding. According to some implementations the proximal end of the light diffusing optical fiber is butt-coupled to the light emitting diode with there being no gap between the proximal end of the fiber and the light emitting side of the light emitting diode.

According to one implementation an assembly is provided that facilitates a coupling of one or more light diffusing optical fibers to one or more light emitting diodes. According to one implementation the assembly includes a light emitting diode positioned inside a cavity of a frame that is equipped with means to directly or indirectly electrically couple the anode and cathode of the light emitting diode to a printed circuit board. A proximal end portion of the light diffusing optical fiber is supported inside a through opening of a lid positioned over a front side of the frame. The light diffusing optical fiber includes a core that is surround by a cladding. According to some implementations the proximal end of the light diffusing optical fiber is butt-coupled to the light emitting diode with there being no gap between the proximal end of the fiber and the light emitting side of the light emitting diode.

Disclosed herein is a method comprising injecting light of a first wavelength .sub.1 into a wavelength division multiplexer; injecting light of a second wavelength .sub.2 into the wavelength division multiplexer; combining the light of the first wavelength .sub.1 and the light of the second wavelength .sub.2 in the wavelength division multiplexer to produce light of a third wavelength .sub.3; and reflecting the light of the third wavelength .sub.3 in a dual-Brillouin peak optical fiber that is in communication with the wavelength divisional multiplexer; wherein the dual-Brillouin peak optical fiber has at least two Brillouin peaks, such that an amplitude A.sub.1 of at least one of said Brillouin peaks is within 50% to 150% of an amplitude A.sub.2 of another Brillouin peak 0.5A.sub.2A.sub.11.5A.sub.2; wherein the dual-Brillouin peak optical fiber generates a Brillouin dynamic grating that reflects an improved back-reflected Brillouin signal of the combined light.

Disclosed herein are various implementations of a fiber optic shape-sensing system comprising a plurality of optical fibers helically twisted and rigidly bonded to form a linearly-running shape-sensing bundle for measuring position, bend, and twist of the shape-sensing bundle, wherein each optical fiber from among the plurality of optical fibers comprises a single core. Several such implementations of the systems further comprise an array of Fiber Bragg Gratings (FBGs) disposed within the core of each single-core optical fiber from among the plurality of single-core optical fibers.

An optical system performs a method for measuring an acoustic signal in a wellbore. The optical system includes a light source, an optical fiber and a detector. The light source generates a light pulse. The optical fiber has a first end for receiving the light pulse from the light source and a plurality of enhancement scatterers spaced along a length of the optical fiber for reflecting the light pulse. A longitudinal density of the enhancement scatterers increases with a distance from the first end to increase a signal enhancement generated by the enhancement scatterers distal from the first end. The detector is at the first end of the optical fiber and measures a reflection of the light pulse at the enhancement scatterers to determine the acoustic signal.

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.

Systems and methods of dispersion compensation in an optical device are disclosed. A holographic optical element may include a set of different holograms in a grating medium. Each hologram in the set may have a corresponding grating vector with a grating frequency and direction. The directions of the grating vectors may vary as a function of the grating frequency. Different holograms in the set may diffract light in a particular direction so that the light emerges from a boundary of the grating medium in a single given direction regardless of wavelength. A prism may be used to couple light into the grating medium. The prism may be formed using materials having dispersion properties that are similar to the dispersion properties of the grating material. The prism may have an input face that receives perpendicular input light. The prism may include multiple portions having different refractive indices.

An opening and closing detection sensor of the present invention includes a fixed base, a moving base, an optical fiber, and a moving member. The moving base is disposed so as to be movable relative to the fixed base. The optical fiber includes an FBG part where a Bragg wavelength varies responding to an interval between the fixed base and the moving base. The moving member moves between a first position corresponding to either one of an opened state or a closed state of an object and a second position corresponding to the other state. The moving member includes a locking part. The locking part abuts on the moving base between a third position located between the first position and the second position, and the second position, thereby moving the moving base together with the moving member, and moving the moving base in a direction separated from the fixed base.

A system installed on an aircraft. The system includes a memory storing static information in one or more optical fibre gratings; and an interrogator. The interrogator includes a light source configured to transmit interrogation light to the memory, a receiver configured to receive return light from the memory, and an analyser configured to analyse the return light to obtain the static information.