An optical device comprises a fiber having a cladding and a core, and a target PIC waveguide having a cladding and a core. The cladding on one side of the input fiber is removed at the end of the fiber and a flat surface is created along the fiber core, close to the core, exposing the fiber core. A flat-bottomed channel having an in-plane angle with respect to the symmetric axis of the PIC waveguide is fabricated on the top layer of the PIC waveguide in the coupling area, exposing the upper surface of the tapered planar waveguide. The flat surface of the fiber and the top surface of the waveguide is contacting, so the core of the fiber is intersected at an angle with respect to the symmetric axis of the target waveguide and close together at the intersection as an interacting region to define a hybrid waveguide.

The present invention provides a tapered side-polished fiber-optic biosensor (FOBS) and a method for preparing a tapered side-polished fiber (SPF). The biosensor includes a broadband light source, a first single-mode fiber, a tapered SPF, a second single-mode fiber, and a spectrometer. The broadband light source is connected to the tapered SPF through the first single-mode fiber, and the tapered SPF is connected to the spectrometer through the second single-mode fiber. The broadband light source is configured to emit a light wave. The spectrometer is configured to display a spectrum corresponding to a light wave passing through the first single-mode fiber, the tapered SPF, and the second single-mode fiber successively. In the present invention, a fiber side-polishing technology is combined with a fiber tapering technology to construct a tapered SPF, and a spectrum changes by changing a refractive index around a side-polished tapered region, thereby measuring the refractive index. In addition, the tapered SPF provided in the present invention can generate a Vernier effect, thereby improving the sensor's anti-electromagnetic interference and sensitivity to refractive index measurement.

An electro-optic beam controller, material processing apparatus, or optical amplifier, and corresponding methods, can include an actively controlled, waveguide-based, optical spatial mode conversion device. The conversion device can include a coupler, which can be a photonic lantern, configured to combine light beams into a common light beam; a sensor configured to measure at least one characteristic of the common light beam; and a controller configured to modulate optical parameters of the individual, respective light beams to set one or more spatial modes of the common light beam. Actively controlled and modulated devices can be used to maintain a stable, diffraction-limited beam for use in an amplification, communications, imaging, laser radar, switching, or laser material processing system. Embodiments can also be used to maintain a fundamental or other spatial mode in an optical fiber even while scaling to kilowatt power.

There is provided a method of manufacturing a cutting element for use in a hair cutting device, the cutting element comprising an optical waveguide, the method comprising providing a preform for an optical waveguide, the preform comprising a core and an outer layer, wherein the outer layer is arranged around the core along the length of the core; forming a shaped preform by removing a portion of the outer layer along the length of the core to expose part of the core, wherein a remaining portion of the outer layer is a support structure for the core; heating the shaped preform; and pulling the shaped preform in the direction of the axis of the core to reduce the cross-section of the shaped preform and form the optical waveguide. Also provided is a cutting element manufactured according to the above method and a cutting element for use in a hair cutting device, the cutting element comprising an optical waveguide comprising a core and a support structure, wherein the support structure contacts the core along the length of the core to support the core, and wherein part of the core is exposed along the length of the core to form a cutting face for contacting hair. The thickness of the support structure tapers linearly or non-linearly from a thin side at which the support structure contacts the core to a thick side.

The evanescent optical coupler is constituted by an IOX waveguide and an optical fiber. The IOX waveguide is formed in a glass substrate and has a tapered section that runs in an axial direction. The IOX waveguide supports a waveguide fundamental mode having an waveguide effective index N.sub.W0 that varies within a range N.sub.W0 as a function of the axial direction. The IOX waveguide can also support a few higher-order modes. The optical fiber supports a fiber fundamental mode having a fiber effective index N.sub.F0 that falls within the waveguide effective index range N.sub.W0 of the waveguide fundamental mode of the tapered section of the IOX waveguide. A portion of the optical fiber is interfaced with the tapered section of the IOX waveguide to define a coupling region over which evanescent optical coupling occurs between the optical fiber and the IOX waveguide.

A method of processing an optical fiber for coupling an external optical signal. The optical fiber has a longitudinal axis, an optical core, and an optical cladding. The method includes processing the optical cladding with a laser beam at a coupling point of the optical fiber along the longitudinal axis between a start and an end region. During the processing, an effective axis of the laser beam is arranged skew with respect to the longitudinal axis of the optical fiber so that the optical cladding is processed via an edge region of the laser beam, and the effective axis of the laser beam is guided along a movement axis which is parallel to or substantially parallel to the longitudinal axis of the optical fiber.

The evanescent optical coupler is constituted by an IOX waveguide and an optical fiber. The IOX waveguide is formed in a glass substrate and has a tapered section that runs in an axial direction. The IOX waveguide supports a waveguide fundamental mode having an waveguide effective index N.sub.W0 that varies within a range N.sub.W0 as a function of the axial direction. The IOX waveguide can also support a few higher-order modes. The optical fiber supports a fiber fundamental mode having a fiber effective index N.sub.F0 that falls within the waveguide effective index range N.sub.W0 of the waveguide fundamental mode of the tapered section of the IOX waveguide. A portion of the optical fiber is interfaced with the tapered section of the IOX waveguide to define a coupling region over which evanescent optical coupling occurs between the optical fiber and the IOX waveguide.

An optical device comprises a fiber having a cladding and a core, and a target PIC waveguide having a cladding and a core. The cladding on one side of the input fiber is removed at the end of the fiber and a flat surface is created along the fiber core, close to the core, exposing the fiber core. A flat-bottomed channel having an in-plane angle with respect to the symmetric axis of the PIC waveguide is fabricated on the top layer of the PIC waveguide in the coupling area, exposing the upper surface of the tapered planar waveguide. The flat surface of the fiber and the top surface of the waveguide is contacting, so the core of the fiber is intersected at an angle with respect to the symmetric axis of the target waveguide and close together at the intersection as an interacting region to define a hybrid waveguide.

Methods for coupling of waveguides with dissimilar mode field diameters, and related apparatuses, components, and systems are disclosed. In one example, a waveguide coupling assembly includes an input waveguide having a first mode, and a transition waveguide having a first transition waveguide section, a second transition waveguide section, and a tapered section. The first transition waveguide section has a second mode and is disposed proximate to the input waveguide such that a phase matching condition is achieved between the input waveguide and the first transition waveguide section, thereby evanescently coupling the input waveguide to the first transition waveguide section of the transition waveguide. The tapered section is optically connected between the first transition waveguide section and the second transition waveguide section, such that the second mode of the first transition waveguide section is converted to the third mode of the second transition waveguide section by the tapered section.

An optical network having at least one star coupler comprising transmit and receive optical mixers which are respectively optically coupled to transmitters and receivers of a plurality of optical-electrical media converters. Each optical-electrical media converter comprises a respective receiver optically coupled to the receive optical mixer by way of plastic optical fibers and a respective transmitter optically coupled to the transmit optical mixer by way of plastic optical fibers. The output plastic optical fibers attached to an output face of the receive optical mixer have a diameter less than the diameter of the input plastic optical fibers attached to an input face of the receive optical mixer.