An embodiment of an optical structure includes a core having first and second ends and a first side with a first grating profile having a first phase shift distributed between the first and second ends, and a cladding disposed around the core. Such an optical structure can be used in an electro-optic modulator (EOM), and can render the EOM smaller in size than currently available EOMs.

An intravascular or other 2D or 3D imaging apparatus can include a minimally-invasive distal imaging guidewire portion. A plurality of thin optical fibers can be circumferentially distributed about a cylindrical guidewire core, such as in an spiral-wound or otherwise attached optical fiber ribbon. A low refractive index coating, high numerical aperture (NA) fiber, or other technique can be used to overcome challenges of using extremely thin optical fibers. Coating and ribbonizing techniques are described. Also described are non-uniform refractive index peak amplitudes or wavelengths techniques for FBG writing, using a depressed index optical cladding, chirping, a self-aligned connector, optical fiber routing and alignment techniques for a system connector, and an adapter for connecting to standard optical fiber coupling connectors.

A device may be provided comprising at least one optoelectronic component and at least one optical waveguide, which are configured to transfer light between the optoelectronic component and the optical waveguide, wherein the optical waveguide contains at least one first longitudinal portion in which at least one Bragg grating is introduced, which has a grating constant which is variable along the longitudinal extent of said Bragg grating, and the optoelectronic component is arranged at a lateral distance from the optical waveguide. Alternatively or in addition, a method may be provided for transferring light between at least one optoelectronic component and at least one optical waveguide.

Structures for a filter and methods of fabricating a structure for a filter. The filter is coupled to a waveguide core. The filter includes a first plurality of grating structures positioned adjacent to a first section of the waveguide core and a second plurality of grating structures positioned adjacent to a second section of the waveguide core. The first plurality of grating structures are configured to cause laser light in a first portion of a wavelength band to be transferred between the first section of the waveguide core and the first plurality of grating structures. The second plurality of grating structures are configured to cause laser light in a second portion of a wavelength band to be transferred between the second section of the waveguide core and the second plurality of grating structures.

A fiber laser device includes: an amplifying fiber; a delivery fiber in which laser light that has been outputted from the amplifying fiber is guided; and a Raman filter that reflects part of Raman scattered light that is generated by stimulated Raman scattering caused to the laser light.

Systems, apparatuses, and methods are described for modifying a beam parameter product of a laser beam. The modified beam parameter product may increase the number of tasks that may be performed using a given laser with its original beam parameter product. By increasing the beam parameter product of a laser, an initial low beam parameter product beam may be used to perform tasks requiring a higher beam parameter product. The beam may be modified to redirect portions of the beam at different angles via one or more non-imaging refracting optical components or by one or more Fiber Bragg gratings.

An eyepiece for an augmented reality display system. The eyepiece can include a waveguide substrate. The waveguide substrate can include an input coupler grating (ICG), an orthogonal pupil expander (OPE) grating, a spreader grating, and an exit pupil expander (EPE) grating. The ICG can couple at least one input light beam into at least a first guided light beam that propagates inside the waveguide substrate. The OPE grating can divide the first guided light beam into a plurality of parallel, spaced-apart light beams. The spreader grating can receive the light beams from the OPE grating and spread their distribution. The spreader grating can include diffractive features oriented at approximately 90 to diffractive features of the OPE grating. The EPE grating can re-direct the light beams from the first OPE grating and the first spreader grating such that they exit the waveguide substrate.

An optical fiber is made of silica-based glass and includes a core, a first cladding that surrounds the core and that has a refractive index lower than a refractive index of the core; and a second cladding that surrounds the first cladding and that has a refractive index lower than the refractive index of the core and higher than the refractive index of the first cladding. At least a part of the first cladding contains a photosensitive material whose refractive index increases by irradiation with light having a specific wavelength. A difference n between a refractive index of a portion of the first cladding, the portion being nearest to the core, and the refractive index of the core is in a range of 0.25% to 0.30%. The radius ra of the core is larger than 4.3 m and smaller than or equal to 5.0 m.

An optical fiber sensing apparatus, system, and method capable of in operando and/or in situ monitoring a state of charge (SOC) of an energy storage device such as a capacitor or a battery is provided. The apparatus comprises an optical fiber having a surface plasmon resonance (SPR)-stimulating structure, exemplarily including a tilted grating in a core, and a SPR-active layer coating a cladding, of the optical fiber. The apparatus is configured such that when arranged in a close proximity with an electrode of the energy storage device, SPR waves are stimulated upon receiving an actuating light. Through analysis of signals of the SPR waves, the SOC of the energy storage device can be determined. The apparatus can also be utilized to capture non-SPR optical waves, analysis of which can further derive information such as temperature, pressure, strain, etc. of the energy storage device and/or be used for calibration.

A structured film for forming a pattern on a substrate includes a polymeric support layer, an adhesive layer, an etch resist layer disposed between the polymeric support layer and the adhesive layer, a structured resin layer disposed between the polymeric support layer and the etch resist layer, and one or more unstructured layers disposed between the etch resist layer and the adhesive layer. The structured resin layer has a structured major surface including a plurality of engineered structures. The etch resist layer at least partially fills spaces between adjacent engineered structures to substantially planarize the structured major surface. Methods of using the structured film to form a pattern on a substrate are described.