Abstract: A light diffusing element diffuses light output from an output facet of an optical fiber that enters the light diffusing element at a first end and outputting the diffused light from a second end. The light diffusing element is equipped with a semireflective surface for reflecting a portion of the light, provided at a predetermined portion of the light diffusing element corresponding to the core of the output facet. The semireflective surface intersects at least with the optical axis of the optical fiber. Thereby, propagation of light in directions away from the optical axis of the optical fiber can be promoted during the step of reflecting the portion of the light that enters the light diffusing element.

Abstract: An electronic device may be provided with imaging modules or communications modules. Imaging modules and communications modules may be improved with the use of plasmonic light collectors. Plasmonic light collectors exploit the interaction between incoming light and plasmons in the plasmonic light collector to redirect the path of the incoming light. Plasmonic light collectors may be used to form lenses for image pixels in an imaging module or to form light pipes or lenses for use in injecting optical communications into a fiber optic cable. Plasmonic lenses may be formed by lithography of metallic surfaces by implantation or by stacking and patterning of layers of materials having different dielectric properties. Plasmonic image pixels may be smaller and more efficient than conventional image pixels. Plasmonic light guides may have significantly less signal loss than conventional lenses and light guides.

Abstract: The invention relates to an optical scattering element suitable for dispersing or scattering light transmitted by optical device by Mie scattering. The optical scattering element comprises a phase-separated or porous borosilicate glass having dispersed phase particles with a particle size of 200 to 500 nanometers or pores with a size of 200 to 500 nanometers, at a number density of 108 to 1012 mm?3. The optical scattering element can be prepared by subjecting a borosilicate glass to a controlled heat treatment to induce phase separation, and then optionally leaching out one of the phases with an acid leach. The optical scattering element can be, for example, attached to an end of an optical fiber or bundle of optical fibers. The invention also relates to a method of dispersing or scattering light by transmitting the light through the optical scattering element.

Abstract: The inventive concept provides optic couplers, optical fiber laser devices, and active optical modules using the same. The optic coupler may include a first optical fiber having a first core and a first cladding surrounding the first core, a second optical fiber having a second core transmitting a signal light to the first optical fiber and a third cladding surrounding the second core, third optical fibers transmitting pump-light to the first optical fiber in a direction parallel to the second optical fiber; and a connector connected between the first optical fiber and the second optical fiber, the connector extending the third optical fibers disposed around the second optical fiber toward the first optical fiber, the connector comprising a third core connected between the first core and the second core and a fifth cladding surrounding the third core.

Abstract: The optical semiconductor device includes a spot-size converter formed on a semiconductor substrate. The spot-size converter has a multilayer structure including a light transition region. The multilayer structure includes a lower core layer, and an upper core layer having a refractive index higher than that of the lower core layer. The width of the upper core layer is gradually decreased and the width of the lower core layer is gradually increased in the light transition region. Both sides and an upper side of the multilayer structure are buried by a semi-insulating semiconductor layer in the light transition region. Light incident from one end section of the spot-size converter is propagated to the upper core layer. The light transits from the upper core layer to the lower core layer in the light transition region, is propagated to the lower core layer, and exits from the other end section thereof.

Abstract: An optical coupling system having an optical coupler and a light-transmissive external medium, the optical coupler comprising a light guide which extends parallel to a main plane of the optical coupler, a mirror surface which is inclined relative to the main plane by an angle of inclination and an outer surface of the coupler which abuts on the medium, the waveguide.

Abstract: The thermal processing device includes a stage, a continuous wave electromagnetic radiation source, a series of lenses, a translation mechanism, a detection module, a three-dimensional auto-focus, and a computer system. The stage is configured to receive a substrate thereon. The continuous wave electromagnetic radiation source is disposed adjacent the stage, and is configured to emit continuous wave electromagnetic radiation along a path towards the substrate. The series of lenses is disposed between the continuous wave electromagnetic radiation source and the stage, and are configured to condense the continuous wave electromagnetic radiation into a line of continuous wave electromagnetic radiation on a surface of the substrate. The translation mechanism is configured to translate the stage and the line of continuous wave electromagnetic radiation relative to one another. The detection module is positioned within the path, and is configured to detect continuous wave electromagnetic radiation.

Abstract: In one embodiment, in an optical device, a bar-shaped optical waveguide has either a polygonal or circular cross-sectional shape. A light entry portion is formed in a circumferential area of a first-end surface of the optical waveguide. The light entry portion includes a sloping surface having a normal vector containing a component in a circumferential direction of the first-end surface. An incident light beam travels towards a second-end surface of the optical waveguide while repeating total reflections on a side surface of the optical waveguide. The incident light beam travels without passing through a central portion in a cross section of the optical waveguide. A light exit portion is formed in the side surface of the optical waveguide. The light exit portion is configured to let the light beam in the optical waveguide out of the optical waveguide.

Abstract: A side-coupling optical fiber assembly comprises a first substrate (200), on a surface of which at least one concave groove is provided; an optical fiber (210) disposed in the concave groove; and a second substrate (220) disposed on the first substrate (200) and pressed on the optical fiber (210). The end of the optical fiber (210) between the first substrate (200) and the second substrate (220) is set as a slant surface (240), which is used for performing total reflection for the light beam transmitted in the optical fiber (210). A method for making the side-coupling optical fiber assembly is provided.

Abstract: An optical coupling device includes an optical fiber holder configured to hold an optical fiber, a wavelength conversion member including a phosphor and an optical characteristic matching member and a wavelength conversion member holder configured to hold the wavelength conversion member. The optical coupling device includes a first region which is formed on an end face of the optical fiber and an end face of the wavelength conversion member, which are optically coupled, when bonding the optical fiber holder and the wavelength conversion member holder, and in which foreign bodies that shield the laser beam are removed from an optical axis of the optical fiber and an optical axis of the wavelength conversion member and a second region which is formed outside the first region when bonding the optical fiber holder and the wavelength conversion member holder, and in which the foreign bodies removed from the first region flow.

Abstract: An novel fiber pump signal combiner is disclosed in which a fiber bundle array is coupled to a double-clad fiber with a taper section that is formed by etching a tapered outer surface into the cladding of a fiber rod to produce a high quality tapered outer surface free of defects with an inner core that has a constant diameter.

Abstract: Exemplary apparatus for obtaining information for a structure can be provided. For example, the exemplary apparatus can include at least one first optical fiber arrangement which is configured to transceive at least one first electro-magnetic radiation, and can include at least one fiber. The exemplary apparatus can also include at least one second focusing arrangement in optical communication with the optical fiber arrangement. The second arrangement can include a ball lens, and be configured to focus and provide there through the first electro-magnetic radiation to generate the focused electro-magnetic radiation. Further, the exemplary apparatus can include at least at least one dispersive third arrangement which can receive a particular radiation (e.g., the first electro-magnetic radiation(s) and/or the focused electro-magnetic radiation), and forward a dispersed radiation thereof to at least one section of the structure.

Abstract: The invention relates to methods and devices for shaping plastic optical fibres (POFs), more specifically for optically modifying and yet more specifically for rapidly joining two portions of the plastic optical fibres to create a new optical connection. The plastic optical fibres may be heated under controlled conditions, to soften them and lens, sensor or patterns may be imprinted on portions of the fibre. Methods are provide to optical joints, and combined physical and optical joints.

Abstract: A sensing device for detecting a physical parameter exemplified by pressures, strains, temperatures, indices of refraction, and combinations thereof. The sensing device comprises a probe having a housing for sealably mounting therein an optical fiber. The optical fiber is provided at its distal end with at least two spaced apart fiber Bragg gratings. The proximal end of the probe is engagable with a holder, and is in communication with fiber Bragg grating interrogation systems. Spacers and seals may be provided about the optical fiber between the fiber Bragg gratings. An orifice may be provided and sealed with a resilient membrane to provide a contained airspace around each fiber Bragg grating. The contained airspace may be optionally filled with a fluid or a gas.

Abstract: The invention provides a method and system of controlling illumination characteristics of a plurality of lighting segments. According to the invention, there is provided an illumination system, comprising: a plurality of lighting segments; a detecting subsystem configured to detect an illumination intensity and/or color of lights emitted from each lighting segment; a controller configured to receive the detecting subsystem's output signals representing illumination intensity and/or color of lights emitted from each lighting segment and to generate sets of driving signals to respectively adjust the driving currents of each lighting segment in response to the output signals, so as to adjust the illumination intensity and/or color of the lights emitted from each lighting segment in accordance with a predetermined illumination setting, wherein each set of driving signals has a unique period feature which is distinguished from that of other sets of driving signals corresponding to other lighting segments.

Abstract: An optical module includes an optical waveguide that transmits and outputs signal light; a circuit board that transmits the signal light output from the optical waveguide, and includes a low refractive-index portion that neighbors and surrounds a transmissive portion and has a lower refractive index than the transmissive portion, which transmits the signal light; and a light-receiving element that includes, on a side toward the circuit board, a light-receiving portion that receives the signal light that has transmitted through the circuit board, where the signal light is reflected toward the light-receiving element at a boundary surface between the transmissive portion and the low refractive-index portion.

Abstract: An illumination system that includes at least one light-diffusing optical fiber is disclosed. The illumination system includes at least one low-scatter light-conducting optical fiber that optically couples the at least one light-diffusing optical fiber to at least one light source. The light-diffusing optical fiber includes a light-source fiber portion having a length over which scattered light is continuously emitted. The light-source fiber portion can be bent, including wound into a coil shape. The light-diffusing optical fiber includes a plurality of nano-sized structures configured to scatter guided light traveling within the light-diffusing optical fiber out of an outer surface of the fiber.

Abstract: A lighting system has one or more light guides capable of guiding light, each comprising a core and two optically smooth faces. A cavity adjacent to two of the optically smooth faces has an opening and a reflective-transmissive surface opposite the opening. A cover having a light source is proximate to and occludes the opening. A major portion of any light emitted from the light source is reflected by the reflective-transmissive surface of the cavity and is injected into the light guides, and a minor portion of any light emitted by the light source is transmitted through the reflective-transmissive surfaces of the cavity and emitted from the lighting system. A light injection coupler is also disclosed that has an optically transmissive housing and suitable for use to couple ends of at least one light guide thereby making a lighting system.

Abstract: Disclosed is an optical fiber having a core with an alkali metal oxide dopant in an peak amount greater than about 0.002 wt. % and less than about 0.1 wt. %. The alkali metal oxide concentration varies with a radius of the optical fiber. By appropriately selecting the concentration of alkali metal oxide dopant in the core and the cladding, a low loss optical fiber may be obtained. Also disclosed are several methods of making the optical fiber including the steps of forming an alkali metal oxide-doped rod, and adding additional glass to form a draw perform. Preferably, the draw preform has a final outer dimension (d2), wherein an outer dimension (d1) of the rod is less than or equal to 0.06 times the final outer dimension (d2). In a preferred embodiment, the alkali metal oxide-doped rod is inserted into the centerline hole of a preform to form an assembly.

Abstract: A light coupling structure, a method of manufacturing a memory cell, and a magnetic recording head are provided. The light coupling structure includes a light coupling layer having a cavity; a waveguide having a cladding layer and a core layer; wherein the cladding layer of the waveguide is disposed in the cavity of the light coupling layer and the core layer of the waveguide is disposed over the light coupling layer and the cladding layer of the waveguide; wherein the light coupling layer is configured to receive light from a light source and couple the received light into the core layer of the waveguide.

Abstract: A cladding stripper includes a plurality of transversal notches or grooves in the outer surface of an exposed inner cladding of a double clad optical fiber. Position and orientation of the notches can be selected to even out cladding light release along the cladding light stripper, enabling more even temperature distributions due to released cladding light. The notches on the optical fiber can be made with a laser ablation system.

Abstract: Embodiments of the invention describe systems, apparatuses and methods for providing athermicity and a tunable spectral response for optical filters. Finite impulse response (FIR) filters are commonly implemented in photonic integrated circuits (PICs) to make devices such as wavelength division multiplexing (WDM) devices, asymmetric Mach-Zehnder interferometers (AMZIs) and array waveguide gratings (AWGs). Athermicity of an FIR filter describes maintaining a consistent frequency transmission spectrum as the ambient temperature changes. A tunable spectral response for an FIR filter describes changing the spectrum of an FIR filter based on its application, as well as potentially correcting for fabrication deviations from the design. In addition, embodiments of the invention reduce energy dissipation requirements and control complexity compared to prior art solutions.

Abstract: A modalmetric fiber sensor comprising a multimode sensor fiber; a light source for launching light into the multimode sensor fiber to produce a multimode speckle pattern of light at an end of the multimode sensor fiber; a single mode fiber to receive light from the multimode speckle pattern; a detector connected to the single mode fiber to detect the received light from the speckle pattern; and a further multimode fiber disposed between the end of the sensor fiber and the single mode fiber such that the single mode fiber receives light from the speckle pattern by transmission through the further multimode fiber and the received light includes higher order modes regenerated in the further multimode fiber, wherein the further multimode fiber is overfilled with received light from the speckle pattern.

Abstract: Described herein are an apparatus, system, and method for providing a vertical optical coupler (VOC) for planar photonics circuits such as photonics circuits fabricated on silicon-on-insulator (SOI) wafers. In one embodiment, the VOC comprises a waveguide made from a material having refractive index in a range of 1.45 to 3.45, the waveguide comprising: a first end configured to reflect light nearly vertical by total internal reflection between the waveguide and another medium, a second end to receive the light for reflection, and a third end to output the reflected light. The VOC couples with a Si waveguide having a first region including: a first end to receive light; and an inverted tapered end in the direction of light propagation to output the received light, wherein the inverted tapered end of the Si waveguide is positioned inside the waveguide.

Abstract: An optical fiber combiner 1 has: a plurality of input optical fibers 20; a plurality of divergence angle reducing members 50 which lights emitted from the respective input optical fibers 20 enter and which emits the lights from the input optical fibers 20 at divergence angles made lower than divergence angles upon entrance; a bridge fiber 30 which the lights emitted from the respective divergence angle reducing members 50 enter and which has a tapered portion 34 which has a portion in which the lights propagate and a diameter of which is gradually reduced apart from a divergence angle reducing member 50 side; and an output optical fiber 40 which a light emitted from a side of the bridge fiber 30 opposite to the divergence angle reducing member 50 side enters.

Abstract: Systems and methods for coupling light into a transparent sheet. The systems include a light source and a light-diffusing optical fiber optically coupled to the light source. The light-diffusing optical fiber has a core, a cladding and a length, with at least a portion of the core comprising randomly arranged voids configured to provide substantially continuous light emission from the core and out of the cladding along at least a portion of the length, and into the transparent sheet.

Abstract: Provided is a lens array that can reliably obtain monitor light and is easy to manufacture. In the provided lens array, light incident on a first lens surface (11) from light-emitting elements is split by a reflective/transmissive layer (17) between a first optical surface (14a) and a first prism surface (16a) and sent, respectively, towards a second lens surface (12) and a third lens surface (13). Monitor light included in the light sent towards the third lens surface (13) is sent by the third lens surface (13) towards a light-receiving element (8). The path of light incident on the first optical surface (14a) is collinear with the path of light outgoing from the second optical surface (14b).

Abstract: A fiber coupler with an inner tube, an inner fiber arranged within the inner tube and several outer fibers arranged around the inner fiber, is disclosed, wherein said fiber coupler tapers in the longitudinal direction of the inner fiber from a main section to a terminal section and the inner cross section on the inner tube corresponds to the diameter of the inner fiber along the tapering section of the fiber coupler.

Abstract: Embodiments of the invention provide apparatuses and methods for phase correlated seeding of parametric mixer and for generating coherent frequency combs. The parametric mixer may use two phase-correlated optical waves with different carrier frequencies to generate new optical waves centered at frequencies differing from the input waves, while retaining the input wave coherent properties. In the case when parametric mixer is used to generate frequency combs with small frequency pitch, the phase correlation of the input (seed) waves can be achieved by electro-optical modulator and a single master laser. In the case when frequency comb possessing a frequency pitch that is larger than frequency modulation that can be affected by electro-optic modulator, the phase correlation of the input (seed) waves is achieved by combined use of an electro-optical modulator and injection locking to a single or multiple slave lasers.

Abstract: An optical resonator supports three resonance modes and having third-order optical nonlinearity. One or more waveguides are coupled to the three resonant modes. A waveguide input port is more strongly coupled to the first resonant mode than to the second and third resonant modes. A waveguide output port is more strongly coupled to at least one of the second and third resonant modes than to the first resonant mode. An optical filter has at least two optical resonators. The optical filter provides a passband having at least two poles and a transmission zero positioned outside the two poles. An optical demultiplexer includes first optical filter coupled in series with a second optical filter. Both optical filters provide a passband having at least two poles and a zero positioned outside the two poles. The zero of the first filter is located within the passband of the second filter.

Abstract: An optical waveguide includes a clad layer, a core layer and a clad layer which are laminated together in this order from a lower side thereof. Within the core layer, a core portion and a side clad portion provided adjacent to the core portion so as to surround side surfaces of the core portion are formed. Further, a part of the side clad portion prevents a left side end of the core portion from being exposed outside. A mirror formation region is constituted from a region consisting of such a part of the side clad portion and a part of each of the clad layers located thereabove and therebelow. This mirror formation region is subjected to digging processing so that a concave portion is formed. An inner surface of this concave portion serves as the mirror. From the mirror, a material other than a material constituting the core portion, that is, a material constituting each of the clad layers and a material constituting the side clad portion are exposed.

Abstract: An optical module includes a substrate including an optical device chip disposed on a top surface thereof, a spacer having at least one through hole and combined with the substrate on the substrate to insert the optical device chip into the through hole, a cover combined with the spacer on the spacer to stop the through hole, and an optical fiber combined with the cover on the cover in a position corresponding to a position of the optical device chip. The optical module is configured such that light transmitted through the optical fiber is incident to the optical device chip or light emitted from the optical device chip is incident to the optical fiber. The optical module may be downscaled and produced in large quantities at low cost.

Abstract: A photonic integrated circuit is provided that may include a substrate; one or more optical sources, on the substrate, to output light associated with a corresponding one or more optical signals; one or more waveguides connected to the one or more optical sources; a multiplexer connected to the one or more waveguides; and one or more light absorptive structures, located on the substrate adjacent to one of the one or more optical sources, one of the one or more waveguides, and/or the multiplexer, to absorb a portion of the light associated with at least one of the corresponding one or more optical signals.

Abstract: A solid state light source comprising a light pump outputting light energy; a waveguide optically coupled to the light pump source for receiving the light energy; and a down-converter for converting the light energy from the waveguide to a lesser light energy.

Abstract: An energy collection system is provided. The system can include an energy collection device and an energy concentration device disposed proximate at least a portion of the energy collection device. The energy concentration device includes a non-periodic, sub-wavelength, dielectric grating.

Abstract: An optical assembly includes a combination of laser sources emitting radiation, focused by a combination of lenses into optical waveguides. The optical waveguide and the laser source are permanently attached to a common carrier, while at least one of the lenses is attached to a holder that is an integral part of the carrier, but is free to move initially. Micromechanical techniques are used to adjust the position of the lens and holder, and then fix the holder it into place permanently using integrated heaters with solder.

Abstract: An optical assembly includes a combination of laser sources emitting radiation, focused by a combination of lenses into optical waveguides. The optical waveguide and the laser source are permanently attached to a common carrier, while at least one of the lenses is attached to a holder that is an integral part of the carrier, but is free to move initially. Micromechanical techniques are used to adjust the position of the lens and holder, and then fix the holder it into place permanently using integrated heaters with solder.

Abstract: There are provided an optical fiber coupler configured to improve or optimize optical efficiency and coupling efficiency, a method of manufacturing the optical fiber coupler, and an active optical module. The optical fiber coupler includes a first optical fiber and second optical fibers. The first optical fiber includes a first core and a first cladding surrounding the first core, and the second optical fibers are coupled to the first cladding. The first cladding includes a first coupling facet to which ends of the second optical fibers are coupled.

Abstract: A method for installing an optical tap into an optical waveguide formed in a printed circuit board which comprises obtaining a printed circuit board having an optical waveguide formed therein, cutting a transverse groove that has a front plane and a back plane into the optical waveguide, such that the back plane of the groove forms an oblique angle relative to the incident beam of light, and inserting a pre-fabricated beamsplitter into the groove so that the beamsplitter is positioned at the oblique angle of incidence relative to the beam of light to enable a predetermined portion of the beam of light to be directed out of the waveguide.

Abstract: The present invention provides a compact optical fiber amplifier, which can minimize the size of an optical module and increase the degree of freedom in mounting the module on a board. The compact optical fiber amplifier according to the present invention includes: an optical module including a plurality of optical elements provided therein, an input port for introducing an optical fiber thereinto, and an outlet port for extract the optical fiber to the outside of the module; and a plurality of optical fibers introduced into or extracted from the optical module through the input port or the outlet port of the optical module and disposed above a predetermined radius of curvature on the outside of the optical module.

Abstract: A new concept of the light guide device has developed to have multi channels, the present invention comprises: a transparent body through which light can freely pass; channel condensing units disposed at predetermined intervals on the body to form a plurality of one-dimensional arrays; an optical module unit for independently sighting incident light, and re-sighting and focusing light which passes through the one-dimensional arrays formed by the channel condensing units disposed at predetermined intervals in the body; and a fiber channel module for creating independent light passages (fiber channels) which condense light from the left, right, up and down aspects of the optical module unit, at a one-to-one correspondence between the body and the optical module unit. The present device maximizes the efficiency of the solar energy utilization by reducing the guide distance of incident light.

Abstract: Methods and apparatus for light detecting and range sensing. In one approach, a light detecting and ranging (LiDAR) sensor uses an optical directing device; a multi-clad optical fiber, a light source, and a detector. The light source is optically coupled to the multi-clad optical fiber which is configured to receive optical rays transmitted from the light source and route the rays on an optical path leading to the optical directing device. The optical directing device is configured both to direct the transmitted optical rays routed through the multi-clad fiber towards a target to be sensed and direct optical rays reflected from the target on an optical path leading to the multi-clad optical fiber. The multi-clad optical fiber is configured to receive the reflected optical rays and route the reflected optical rays on an optical path leading to the detector. The detector is configured to detect the reflected optical rays.

Abstract: A light source is coupled to an input facet that directs light from the light source to a core layer of a waveguide and a gradient index material layer disposed beside the core layer along a portion of a propagation length of the waveguide. Light is launched from the light source into the input facet. In response, the gradient index material layer directs light to the core layer at least along the portion of the propagation length.

Abstract: A frequency-chirped nano-antenna provides efficient sub-wavelength vertical emission from a dielectric waveguide. In one example, this nano-antenna includes a set of plasmonic dipoles on the opposite side of a SiYV4 waveguide from a ground plane. The resulting structure, which is less than half a wavelength long, emits a broadband beam (e.g., >300 nm) that can be coupled into an optical fiber. In some embodiments, a diffractive optical element with unevenly shaped regions of high- and low-index dielectric material collimates the broadband beam for higher coupling efficiency. In some cases, a negative lens element between the nano-antenna and the diffractive optical element accelerates the emitted beam's divergence (and improves coupling efficiency), allowing for more compact packaging.

Abstract: An optical connector having a plurality of directional taps and connecting between a plurality of optical waveguides (e.g., such as a connector between a waveguide that is part of, or leads from, a seed laser and/or an initial optical-gain-fiber power amplifier, and a waveguide that is part of, or leads to, an output optical-gain-fiber power amplifier and/or a delivery fiber), wherein one of the directional taps extracts a small amount of the forward-traveling optical output signal from the seed laser or initial power amplifier (wherein this forward-tapped signal is optionally monitored using a sensor for the forward-tapped signal), and wherein another of the directional taps extracts at least some of any backward-traveling optical signal that may have been reflected (wherein this backward-tapped signal is optionally monitored using a sensor for the backward-tapped signal).

Abstract: A coupling device for an optical waveguide includes an optical waveguide connection for a first optical waveguide. The coupling device includes an optical filter arranged in a beam path between a laser light source and the optical waveguide connection which reflects light of a first wavelength range or a first polarization direction and transmits light of a second wavelength range or a second polarization direction.

Abstract: An optical coupling module includes a substrate, a circuit board defining two through holes, an optical waveguide positioned between the substrate and the circuit board, and an optical assembly. The optical waveguide includes a core and a clad, each core comprises two coupling surfaces corresponding to the two through holes. At least one coupling surfaces is in an arcuate shape. The clad covers the core, except for the two coupling surfaces exposing out of the clad. The optical assembly formed on the circuit board comprises an optical emitting element and an optical receiving element. The optical emitting element and the optical receiving element are positioned above the two through holes, respectively. Light emitted from the optical emitting element enters the optical waveguide via one of the coupling surface, and leaves from another coupling surface to reach the optical receiving element. The coupling surface is capability of focusing light.

Abstract: An optical adapter includes a loading plate and a coupling lens. The coupling lens includes a main body, a first optical reflector, and a second optical reflector. The first optical reflector is positioned on the loading plate. The main body includes a top plate made of transparent material and spaced a predetermined distance from the loading plate. The second optical reflector is positioned on the first top plate. The first loading plate loads a portion of a planar optical waveguide of an optical printed circuit board. An optical signal from the planar optical waveguide is reflected by the first optical reflector to the second optical reflector, then is reflected by the second optical reflector to the outside of the optical adapter.

Abstract: A Mach-Zehnder interferometer (MZI) incorporates a tunable multimode interference (MMI) coupler comprising a tunable MMI coupler with a tuning electrode on a surface of a tunable MMI region and an electrically insulating region provided within the tunable MMI region. The MMI region is tunable in response to detection of a photocurrent by a photodetector section. Such a tunable MZI is particularly advantageous in enabling a split ratio of an optical splitter, the split ratio and the splitter to be controlled in a particularly efficient manner.

Abstract: An apparatus consisting of stacked slab waveguides whose outputs are vertically staggered is disclosed. At the input to the stacked waveguides, the entrances to each slab lie in approximately the same vertical plane. A spot which is imaged onto the input will be transformed approximately to a set of staggered rectangles at the output, without substantial loss in brightness, which staggered rectangles can serve as a convenient input to a spectroscopic apparatus. A slit mask can be added to spatially filter the outputs so as to present the desired transverse width in the plane of the spectroscopic apparatus parallel to its dispersion.