A device for combining several light beams, the device including several hollow input waveguides, at least one per light beam, as well as a hollow output waveguide which is the same for the different light beams, each input waveguide having an input opening to let the corresponding light beam enter, and, at the opposite, an output opening through which it emerges in the output waveguide, the output waveguide, as well as each input waveguide being laterally delimited by one or more metallic reflecting surfaces, and wherein at least a section of the output waveguide is divergent and widens in the direction of an output opening of the output waveguide.

An assembly for redirecting light emitted by an end-emitting optical fiber into an inner lumen of a body is provided. According to one implementation, the body includes one or more surfaces disposed on or in the body onto which the light is configured to impinge when the end emitting optical fiber is activated, the one or more surfaces being configured to alter the trajectory of the light so that the light is directed to impinge on a light reflector of a cap removably attached to the body, the light reflector of the cap being configured to redirect the light distally into the inner lumen of the body.

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.

A system for sensing analyte in at least partly translucent material, including one or more radiation sources configured for successively providing radiation at a first and a second wavelength, respectively, two or more waveguides for simultaneously transmitting the radiation at each wavelength provided by the radiation source, a first waveguide being a reference waveguide and a second being a sensing waveguide; and measuring means for measuring a phase difference between the radiation waves from the reference waveguide and the measuring waveguide, resp. The present method can be used for measuring contaminants such as Fe, Sn, and/or Pb in oil related products, such as carburant or lubricant.

Infrared Remote Over Video Fiber (IROVF) transports any combination of uncompressed/unprocessed/native full quality, full bandwidth, zero latency, and mixed analog and digital signals including audio, video, data, Ethernet, USB, S/PDIF, and TOSLINK, over a fiber optic based cable added with integrated infrared remote control capabilities to remote control uni/bi-directional audio video and IR devices remotely from either sides of the cable Without requiring additional processing adapters, nor processing or reducing the specs of the other carried audio-video data signals which stays original uncompressed, untouched, and unprocessed for a perfect as-is full original functionality and quality.

The invention provides a light guide element comprising a light guide and a layer element, wherein the light guide comprises a light guide face and wherein the layer element comprises an optical layer, wherein said optical layer is in contact with at least part of the light guide face, wherein the optical layer has a first index of refraction (n1) smaller than the refractive index of seawater, wherein the light guide comprises a UV radiation transmissive light guide material.

A head-mounted device may have displays that provide images. Waveguides may be used in conveying the images to eye boxes. The waveguides may overlap lenses in a glasses frame or other head-mounted support structure. The waveguides and lenses may be transparent. This allows real-world objects to be viewed from the eye boxes. Infrared-light reflectors may overlap the lenses. Gaze tracking system light sources may supply infrared light that reflects from the infrared-light reflectors to the eye boxes to illuminate a user's eyes. Gaze tracking system cameras capture gaze tracking images of the eyes from the eye boxes to track the user's gaze. Fiducials associated with the infrared-light reflectors may be monitored using the gaze tracking system cameras. This allows components such as the gaze tracking system cameras to be calibrated.

An optical device includes a concave-convex structure layer having a concavo-convex structure on a surface thereof, the concavo-convex structure formed of a plurality of convexities or a plurality of concavities which are arranged with a sub-wavelength period, a high refractive index layer made of a material having a refractive index higher than that of the concavo-convex structure layer and located on the concavo-convex structure while having a surface conforming to the concavo-convex structure, and a low refractive index layer made of a material having a refractive index lower than that of the high refractive index layer and located on the high refractive index layer. The high refractive layer includes first grating high refractive index portions located at a bottom of the concavo-convex structure to form a first sub-wavelength grating, and second grating high refractive index portions located at a top of the concavo-convex structure to form a second sub-wavelength grating.

A terahertz hollow core waveguide includes several successively cascaded waveguide units, and the waveguide units includes fiber core and cladding. The fiber core is composed of air, and the cladding is composed of dielectric rings, air rings, support strips, and an outer cladding. The medium rings and the air rings are successively surrounded on the outside of the fiber core, and the outer cladding is surrounded on the outside of the outermost air ring. All support strips in the same air ring of the same waveguide unit form a support strip group, and the support strips in the support strip group are arranged along the circumferential direction to connect two adjacent dielectric rings in the same waveguide unit or to connect the outermost dielectric ring and the outer cladding in the same waveguide unit.

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.