Abstract: MEMS-actuated optical switches can be implemented on photonic chips. These switches are compact, essentially planar, simple to implement and include only one moving MEMS component per switch. The switches exhibit low optical loss, require low power to operate, and are simple to control and easy to integrate with other optical devices. Each switch has two optical waveguides that are optically coupled in an ON switch state and not coupled in an OFF switch state. An end or a medial section of one of the two waveguides may translate between the ON and OFF states to affect the coupling. Alternatively, a coupling frustrator may translate between the ON and OFF states to affect the coupling.

Abstract: A semiconductor detector (100) for electromagnetic radiation within a wavelength range is disclosed, comprising a first waveguide portion (110), a funnel element (130) configured to funnel incident electromagnetic radiation into a first end (112) of the first waveguide portion, and a second waveguide portion (120) extending in parallel with the first waveguide portion. The second waveguide portion is coupled to the first waveguide portion and configured to out-couple electromagnetic radiation from the first waveguide portion, within a sub-range of the wavelength range. Further, a photodetector (140) including a photoactive layer (144) is arranged at a second end (114) of the first waveguide portion and at an end (124) of the second waveguide portion, and configured to separately detect electromagnetic radiation transmitted through and exiting the first waveguide portion and the second waveguide portion.

Abstract: An optical system includes a laser source that provides a beam of light, a photonic integrated circuit (PIC) with an input aperture, and an alignment fixture that has at least one actuator. The alignment fixture may be mounted on the PIC. The optical system is aligned such that the beam of light travels from the laser source to the alignment fixture and from the alignment fixture to the input aperture of the PIC. The alignment fixture can move in at least one direction upon actuation of the at least one actuator to adjust coupling between the laser source and the PIC. The at least one actuator may be a micro-electro-mechanical system (MEMS) structure actuated by an electrical signal.

Abstract: A wave conductor for electromagnetic waves, waveguide connector and communications link A wave conductor for electromagnetic waves, preferably a millimeter-wave wave conductor, in particular for a digital communication application, with a conductor core and a one conductor sheathing. The conductor sheathing surrounds the conductor core at least partially in the longitudinal direction and at least partially in the circumferential direction of the wave conductor. One longitudinal section of the wave conductor has cross-sections which deviate from a circle at the outside of the wave conductor and/or at the outside of the conductor sheathing. Further, a waveguide connector for electromagnetic waves, preferably millimeter-wave waveguide connectors, in particular flying or installable waveguide connectors for a wave conductor. The waveguide connector has a wave conductor plug-in recess in which a longitudinal section of the wave conductor is directly placeable.

Abstract: A retention assembly for coupling a cable including a plurality of optical fibers to a support may include a retention anchor configured to be coupled to a support and a retention coupler configured to be coupled to a cable. The retention anchor may include a mounting plate configured to be coupled to a support and defining an entry hole extending through the mounting plate and an engagement slot extending from a periphery of the entry hole. The retention coupler may include a retention support and a retainer blade coupled to a first coupler face of the retention support via an extension. The retainer blade may be configured to be passed through the entry hole, such that the extension extends through the entry hole of the mounting plate, and the extension slides within the engagement slot of the mounting plate.

Abstract: A two-fiber Quad Small Form-factor Pluggable electro-optical transceiver (QSFP) currently connects to two optical fibers, one for transmission and one for reception. In accordance with an embodiment of the disclosure, a three-port optical circulator may be employed in order to achieve bidirectional transmission (BiDi) on a single fiber. The disclosure provides in accordance with an embodiment of the disclosure a miniature optical circulator that clips onto the two-fiber QSFP without protruding from the QSFP extraction lever, and is configured to mate with the two QSFP fiber connectors on one side and a single optical fiber on the other. Another embodiment provides an integrated bidirectional QSFP that is configured to mate with a single bidirectional fiber.

Abstract: An example system for multi-wavelength optical signal splitting is disclosed. The example disclosed herein comprises a first splitter, a second splitter, and a modulator. The system receives a multi-wavelength optical signal and an electrical signal, wherein the multi-wavelength optical signal comprises a plurality of optical wavelengths and has a power level. The first splitter is to split the plurality of optical wavelengths into a plurality of optical wavelength groups. The second splitter is to split the multi-wavelength optical signal or the plurality of optical wavelength groups into a plurality of lower power signal groups. The modulator is to encode the electrical signal into the plurality of optical wavelength groups, the plurality of lower power signal groups, or a combination thereof.

Abstract: Two input waveguides are made of a semiconductor material. One output waveguide is made of a semiconductor material. A multi-mode-interference part is made of a semiconductor material. The multi-mode-interference part has an incoming end surface connected to the input waveguides, and an outgoing end surface opposite to the incoming end surface and connected to the output waveguide. The multi-mode-interference part has a waveguide width wider than the waveguide widths of the input waveguides and the waveguide width of the output waveguide. Two unwanted-light waveguides are made of a semiconductor material. The unwanted-light waveguides are connected to the outgoing end surface of the multi-mode-interference part so as to sandwich the output waveguide. The unwanted-light waveguides each satisfy a single-mode condition.

Abstract: An array substrate and a magneto-optical switch display. The array substrate includes: a thin film transistor T, a coil connected with the thin film transistor, and a magneto-optic crystal interposed in the coil, the coil and the magneto-optic crystal constituting a magneto-optical switch structure, and the magneto-optical switch structure can change a transmission rate of emergent light transmitting through the array substrate.

Abstract: An electro-optical link is provided. In an example embodiment, the electro-optical link includes a number of vertical cavity surface emitting lasers (VCSELs); one or more drivers that operate the VCSELs such that each of the VCSELs selectively emits an optical signal; one or more multiplexers that multiplex a number of optical signals into an optical fiber, each optical signal emitted by one of the VCSELs; and one or more optical fibers. At least two optical signals are multiplexed into each optical fiber of the one or more optical fibers. In some example configurations eight or sixteen optical signals are multiplexed into one optical fiber.

Abstract: An optical signal transmission system comprising a multimode optical fiber link. The multimode optical fiber link is for transmission of a plurality of optical signals in a plurality of spatial modes supported by the multimode optical fiber link. The optical signal transmission system comprises a photonic device in the form of a spatial mode add drop multiplexer coupled to the multimode optical fiber link and configured for at least one of coupling into the multimode optical fiber link an optical signal of the plurality of optical signals into a spatial mode of the plurality of spatial modes and coupling out of the multimode optical fiber link and into an optical fiber the optical signal of the spatial mode.

Abstract: Consistent with the present disclosure, an apparatus for producing a control signal for a laser source is provided, comprising an etalon configured to receive light from the laser source and control circuitry that provides the control signal, wherein the control signal is indicative of a comparison of (a) a difference between a forward transmission signal of the etalon and a backward reflection signal of the etalon and (b) the light received by the etalon from the laser source. Alternatively, the control signal is indicative of a comparison of (a) a difference between a forward transmission signal of the etalon and a backward reflection signal of the etalon and (b) a combination of the forward transmission signal of the etalon and the backward reflection signal of the etalon.

Abstract: A sensor line, a measuring arrangement and a method detect a change in an ambient variable. The sensor line serves for detecting a change in an ambient variable, in particular the temperature. The sensor line has a first optical waveguide, a second optical waveguide and also a material that changes its transparency depending on the value of the ambient variable. The material is positioned between the first optical waveguide and the second optical waveguide in such a way that light from the first optical waveguide is able to be coupled into the second optical waveguide in an event of a change in the transparency.

Abstract: An optoelectronic system comprising a first member and a second member, said first member and said second member comprising a plurality of layers, wherein each member has a profiled mating surface, the first member being connected to the second member such that the growth direction of the layers of the first member are orthogonal to the growth direction of the layers of the second member and the profiled mating surfaces fit together, the first member comprises a waveguide circuit comprising a waveguide and the second member comprises an optoelectronic device with its own optical output which is connected to the waveguide of the first member, the first and second members also being electrically connected.

Abstract: An illumination device and method including multiple illumination sources such as LEDs, lasing diodes or the like operatively connected to a multi-branch light guide adapted to collect and co-align beams from the illumination sources for delivery of high intensity, spatially uniform illumination.

Abstract: An optical fiber cord includes: a multi-fiber cord section that includes an outer cover that encloses an optical fiber unit where a plurality of coated optical fibers are gathered; a plurality of branch cord sections where the coated optical fibers are housed in branch tubes; and a branch protection section that includes an exterior member that covers a branch portion where the plurality of coated optical fibers are branched from the multi-fiber cord section toward the branch cord sections.

Abstract: Disclosed is an optical gas sensor. The optical gas sensor includes: a light source which emits light; a gas collector which includes a cavity to be filled with gas to be sensed; an optical wave guider which guides light emitted from the light source to be output to the cavity, and guides the output light to be output again to the cavity after passing through the cavity of the gas collector; and an optical detector which detects light output from the optical wave guider. Thus, a path of light exposed to the gas to be sensed is increased within the cavity, thereby achieving miniaturization and sensing gas of low-concentration.

Abstract: Disclosed is an optical semiconductor device which can be improved in light shift precision and restrained from undergoing a loss in light transmission. In this device, an inner side-surface of a first optical coupling portion of an optical coupling region and an inner side-surface of a second optical coupling portion of the region are increased in line edge roughness. This manner makes light coupling ease from a first to second optical waveguide. By contrast, the following are decreased in line edge roughness: an outer side-surface of the first optical coupling portion of the optical coupling region; an outer side-surface of the second optical coupling portion of the region; two opposed side-surfaces of a portion of the first optical waveguide, the portion being any portion other than the region; and two opposed side-surfaces of a portion of the second optical waveguide, the portion being any portion other than the region.

Abstract: In photonic integrated circuits implemented in silicon-on-insulator substrates, non-conductive channels formed, in accordance with various embodiments, in the silicon device layer and/or the silicon handle of the substrate in regions underneath radio-frequency transmission lines of photonic devices can provide breaks in parasitic conductive layers of the substrate, thereby reducing radio-frequency substrate losses.

Abstract: An information processing system, device and method wherein a base board is configured to couple to both back and midplane systems as well as optical modules for use in a data center rack system. Specifically, a base board adapter is configured to electrically couple to an integrated backplane/midplane electronic interface of the base board and translate the signals to one or more optical interface module connectors such that one or more optical interface modules are able to be coupled to the base board.

Abstract: An optical module includes an optical element having a group of first pads which is formed on a first surface thereof, a substrate having a group of second pads which is formed on a second surface thereof facing the first surface so as to correspond to the group of first pads, respectively, and a group of solders that respectively bonds the group of first pads and the group of second pads to each other, wherein, in a plan view, the corresponding first and second pads partially overlap each other, and a center of gravity of the group of first pads coincides with a center of gravity of the group of second pads.

Abstract: Aspects of the subject disclosure may include, receiving a signal, and launching, according to the signal, an electromagnetic wave along a transmission medium, where the electromagnetic wave propagates along the transmission medium without requiring an electrical return path, and where the electromagnetic wave has a phase delay profile that is dependent on an azimuth angle about an axis of the transmission medium. Other embodiments are disclosed.

Abstract: An optical module for connecting photoelectric conversion device on a substrate to a ferrule connected to an optical fiber includes a body configured to be mounted on the substrate, a first lens disposed on the body at a side thereof connectable to the ferrule, a second lens disposed on the body at a side thereof facing the substrate, and a core disposed in the body between the first lens and the second lens, wherein a refractive index of the core is higher than a refractive index of the body.

Abstract: A light device using a light cylinder is disclosed. The light device includes a cover, a light source section combined with at least part of an inside surface of the cover and configured to output a light, and a light cylinder configured to include one entrance part and a plurality of output parts. The entrance part is combined with the light source section, and the light incident through the entrance part is outputted through the output parts.

Abstract: To effectively prevent the acceleration of the drift phenomenon generated by the application of a high electric field to a substrate through a bias electrode in a waveguide type optical element. A waveguide type optical element includes a substrate (100) having an electro-optic effect, two optical waveguides (104 and 106) disposed on a surface of the substrate, a non-conductive layer (120) which is disposed on the substrate and is made of a material having a lower dielectric constant than the substrate, and a control electrode (150) which is disposed on the non-conductive layer and is intended to generate a refractive index difference between the two optical waveguides by respectively applying electric fields to the two optical waveguides, and the non-conductive layer is constituted of a material which includes silicon oxide, an oxide of indium, and an oxide of titanium and has a ratio between a molar concentration of the titanium oxide and a molar concentration of indium oxide of 1.

Abstract: In an optical modulator, a light-receiving element, and an output port are disposed in a substrate. In addition, at least a part of an electrical line, which electrically connects the light-receiving element and the output port to each other, is formed in the substrate. In addition, a plurality of the optical modulation sections are provided. In addition, among a plurality of the light-receiving elements which are provided to the optical modulation sections, at least one light-receiving element is disposed at a position different from positions of the other light-receiving elements in a light wave propagating direction. A plurality of the output ports are disposed in an arrangement in the light wave propagating direction in correspondence with an arrangement of the plurality of the light-receiving elements in the light wave propagating direction.

Abstract: Systems, methods, and apparatus for an optical sub-assembly (OSA) are disclosed. In one or more embodiments, the disclosed apparatus involves a package body, and a lock nut, where a first end of the lock nut inserted into a first cavity of the package body. The apparatus further involves a transistor outline (TO) can, where a first end of the TO can is inserted into a second cavity of the package body. Also, the apparatus involves an optical fiber, where a portion of the jacket from an end of the optical fiber is stripped off, thereby exposing bare optical fiber at the end of the optical fiber. The end of the optical fiber is inserted into a second end of the lock nut such that the bare optical fiber passes into the package body and at least a portion of the bare optical fiber is inserted into the TO can cavity.

Abstract: A temperature insensitive DEMUX/MUX device whose wavelength does not change by environment temperature is provided for WDM application. The temperature insensitive DEMUX/MUX device includes a waveguide-based delay-line-interferometer configured to receive an input light bearing multiplexed wavelengths and output a first output light bearing the same multiplexed wavelengths but with a shifted intensity peak position. The first output light is transmitted into a DEMUX device through a first free space coupler and a grating fiber or waveguide to be demultiplexed for forming a plurality of second output lights each bearing an individual wavelength. The DEMUX device includes a second free space coupler for refocusing each second output light to corresponding output channel. The shifted intensity peak position of the first output light is tunable to make each second output light free from any temperature-induced drift off corresponding output channel.

Abstract: An optical multi-mode HIC (high index contrast) waveguide (102, 104, 201, 301) for transporting electromagnetic radiation in the optical waveband, the waveguide comprising a guiding core portion (204) with higher refractive index, and cladding portion (206) with substantially lower refractive index configured to at least partially surround the light guiding core in the transverse direction to facilitate confining the propagating radiation within the core, the waveguide being configured to support multiple optical modes of the propagating radiation, wherein the waveguide incorporates a bent waveguide section (202) having bend curvature that is configured to at least gradually, preferably substantially continuously, increase towards a maximum curvature of said section from a section end.

Abstract: Ferrule for an optical connector, an optical connector containing such a ferrule, and a method for assembling such a ferrule. The ferrule includes a base, at least one cover, at least one fiber section running through a channel between the base and the cover from a cable connection side to an opposite contact face exposing distal ends of the fiber sections. The fibers are adhered to the base and/or to the cover at a bonding section at a distance from the contact face.

Abstract: A system, apparatus, or method may include an optical connector that is configured to be fixed to a substrate including an optical waveguide. The substrate may also include a reference mark spaced away from the optical waveguide and extending from a substrate edge. The optical connector may define a first alignment aperture and a second alignment aperture through which the optical connector may be aligned with the substrate (e.g., the optical waveguide). The first alignment aperture may be configured to be aligned with the reference mark and the second alignment aperture may be configured to be aligned with the substrate edge.

Abstract: A photoelectric conversion device includes a circuit board, a light emitting module, a light receiving module, and an optical coupling lens. The circuit board includes two positioning portions apart from each other. The light emitting module and the light receiving module are mounted on the circuit board, and are spaced apart from each other. The optical coupling lens includes a bottom surface facing the light emitting module and the light receiving module, two first converging portions formed on the bottom surface, and two locating portions. Centers of the positioning portions are aligned with centers of the locating portions to ensure perfect alignment of the light emitting module and the light receiving module with the first converging portions.

Abstract: The present invention provides a water quality sensor for household appliance which is installed inside of a washing appliance, including a housing and a detecting module contained therein. The detecting module includes a light emitting element for emitting a detecting beam passing through the transparent panel, and a light receiving element for receiving a backscattered beam generated from the detecting beam and backscattered by the cleaning medium. The light emitting element and the light receiving element are positioned on a same plane of a circuit board parallel to the transparent panel, and the detecting beam emitted from the light emitting element is blocked by a sensor holder from being directly received by the light receiving element, such that the water quality sensor determines the water quality of the cleaning medium contained in the household appliance based on the backscattered beam.

Abstract: A structure includes a combination of a stub fabricated on a polymer and a groove fabricated on a silicon (Si) chip, with which an adiabatic coupling can be realized by aligning a (single-mode) polymer waveguide (PWG) array fabricated on the polymer with a silicon waveguide (SiWG) array fabricated on the silicon chip. The stub fabricated on the polymer is patterned according to a nano-imprint process along with the PWG array in a direction in which the PWG array is fabricated. The groove fabricated on the silicon chip is fabricated along a direction in which the SiWG array is fabricated.

Abstract: A pluggable optical transceiver that enhances the heat dissipation function is disclosed. The optical transceiver provides the MPO connector that receives an external MT ferrule, the assembly substrate that installs a semiconductor optical device, a lens block that bends the optical axis of the semiconductor optical device by about 90°, the circuit board electrically connected to the assembly substrate, the inner fiber optically couples the MPO connector with the lens block, and the top and bottom housings that installs the MPO connector, the assembly substrate, the circuit board, and the inner fiber therein. The bottom housing mounts the circuit board, while, the assembly substrate is thermally and physically in contact to the top housing through a thermal grease.

Abstract: The invention relates to the field of display technology, and particularly to a surface light source, a backlight module and a display device. The surface light source of the invention comprises at least one optical fiber and at least one light source, wherein the at least one light source is provided at one end of the at least one optical fiber one to one, the at least one optical fiber each is provided with a plurality of light outgoing windows along its length direction, a light beam emitted from each light source propagates in a corresponding optical fiber, and outgoes from the optical fiber through the plurality of light outgoing windows. The surface light source and the backlight module adopting the surface light source have advantages of wide gamut, high efficiency and high light focusing effect. The display device adopting the backlight module has better display effect.

Abstract: A temperature insensitive DEMUX/MUX device whose wavelength does not change by environment temperature is provided for WDM application. The temperature insensitive DEMUX/MUX device includes a waveguide-based delay-line-interferometer configured to receive an input light bearing multiplexed wavelengths and output a first output light bearing the same multiplexed wavelengths but with a shifted intensity peak position. The first output light is transmitted into a DEMUX device through a first free space coupler and a grating fiber or waveguide to be demultiplexed for forming a plurality of second output lights each bearing an individual wavelength. The DEMUX device includes a second free space coupler for refocusing each second output light to corresponding output channel. The shifted intensity peak position of the first output light is tunable to make each second output light free from any temperature-induced drift off corresponding output channel.

Abstract: The optical fiber connector assembly includes a first connector and a second connector. The first connector includes at least two positioning pillars corresponding to the optical fibers. The first connector defines at least two optical fiber holes for receiving and positioning the optical fiber. Each optical fiber hole passes through a distal end of a corresponding positioning pillar. The second connector defines at least two positioning holes corresponding to the positioning pillars. Each positioning hole includes an end surface in the second connector. The second connector includes at least two first lenses corresponding to the optical fibers. Each first lens is positioned on the end surface of a corresponding positioning hole. The optical fibers are respectively aligned with the first lenses by an engagement of the positioning posts and the positioning holes.

Abstract: The present invention relates to a compact tunable laser device that can change the oscillation laser wavelength.

Abstract: An integrated optical semiconductor device includes a substrate including first and second regions; a plurality of light receiving devices disposed in the second region; a multimode interference coupler disposed in the first region, the multimode interference coupler including output optical waveguides optically coupled to the corresponding light receiving devices; first and second conductive layers disposed on a back surface of the substrate in the first and second regions, respectively; and a plurality of capacitors disposed in the second region, each of the capacitors including a first electrode connected to one of the light receiving devices and a second electrode connected to the second conductive layer. The second conductive layer is electrically insulated from the first conductive layer. The substrate is made of a semi-insulating semiconductor. The multimode interference coupler and the light receiving devices include the same n-type semiconductor layer disposed on a principal surface of the substrate.

Abstract: Suspended structures are provided using selective etch technology. Such structures can be protected on all sides when the selective undercut etch is performed, thereby providing excellent control of feature geometry combined with superior material quality.

Abstract: A device for Laser based Analysis using a Passively Q-Switched Laser comprising an optical pumping source optically connected to a laser media. The laser media and a Q-switch are positioned between and optically connected to a high reflectivity mirror (HR) and an output coupler (OC) along an optical axis. The output coupler (OC) is optically connected to the output lens along the optical axis. A means for detecting atomic optical emission comprises a filter and a light detector. The optical filter is optically connected to the laser media and the optical detector. A control system is connected to the optical detector and the analysis electronics. The analysis electronics are optically connected to the output lens. The detection of the large scale laser output production triggers the control system to initiate the precise timing and data collection from the detector and analysis.

Abstract: An optical device includes a transparent substrate and a conductive layer disposed over an upper surface of the transparent substrate. The conductive layer defines at least one groove inwardly extending from an upper surface and includes an aperture that is spaced apart from the at least one groove. An interface between the upper surface of the conductive layer and an ambient medium defines an optical branch along which surface plasmon polariton modes are excited in response to at least partially coherent light being received by the optical device.

Abstract: Optical devices that include one or more structures fabricated from polar-dielectric materials that exhibit surface phonon polaritons (SPhPs), where the SPhPs alter the optical properties of the structure. The optical properties lent to these structures by the SPhPs are altered by introducing charge carriers directly into the structures. The carriers can be introduced into these structures, and the carrier concentration thereby controlled, through optical pumping or the application of an appropriate electrical bias.

Abstract: The modulator includes a ring resonator having a phase modulator that tunes blocked wavelengths within phase modulator bandwidths. The blocked bands include blocked wavelengths at which the intensity of an output light signal is minimized. Each of the blocked bands is associated with the phase modulator bandwidth within which the blocked wavelength is tuned. A bandwidth shifting device is configured to shift a selection of wavelengths that falls within each of the phase modulator bandwidths. Electronics are configured to operate the bandwidth shifting device so as to shift the phase modulator bandwidths from a location where a first target wavelength falls within a first one of the phase modulator bandwidths to a location where a second target wavelength falls within a second one of the phase modulator bandwidths.

Abstract: An artificial electromagnetic material is provided. The artificial electromagnetic material includes at least one material sheet. Each material sheet includes a laminary substrate and a plurality of artificial microstructures attached to the substrate. The substrate is made from transparent material. Because the substrate is made from transparent material, therefore the artificial electromagnetic material is capable of generating responses to visible light wave and convergence, divergence, deflection of visible light wave and so on can be achieved.

Abstract: A connector provided on a projector has an RF chip. A plug connected to the connector has an RF chip at a position opposite to the RF chip of the connector. When a protruding section of the plug is inserted and fit into an aperture section of the connector, the RF chip of the plug and the RF chip of the connector perform wireless communication with each other in a non-contact state. Thus, a connecting tool can be easily attached to/detached from a receiving tool without breaking a terminal due to contact such as in a case where a conventional contact type terminal is used.

Abstract: An all optical radio frequency converter. The invention relates to a microtoroid optomechanical oscillator that can provide a local oscillation frequency and a mixing functionality. The microtoroid optomechanical oscillator can be fabricated from a silica-on-silicon wafer. When an input optical signal having an optical carrier frequency carrying a modulated RF signal representing information is applied to the microtoroid optomechanical oscillator, a signal including the baseband information modulated on the optical carrier is provided as output. The output signal can be detected with a photodetector. Information carried by the optical signal can be recorded and/or displayed to a user. Injection locking of the microtoroid optomechanical oscillator can be accomplished by providing a signal of suitable frequency. The frequency and the phase of operation of the microtoroid optomechanical oscillator can be locked to the respective frequency and phase of the injected locking signal.

Abstract: Optical devices that include one or more structures fabricated from polar-dielectric materials that exhibit surface phonon polaritons (SPhPs), where the SPhPs alter the optical properties of the structure. The optical properties lent to these structures by the SPhPs are altered by introducing charge carriers directly into the structures. The carriers can be introduced into these structures, and the carrier concentration thereby controlled, through optical pumping or the application of an appropriate electrical bias.

Abstract: Embodiments disclosed herein generally relate to optical couplers for transmitting an optical signal between a waveguide in an optical device to an external light-carrying medium and vice versa. The couplers include first and second portions that extend away from the waveguide towards an optical interface that faces the light-carrying medium. The first portion is attached to the waveguide, while the second portion is not. In one example, a first end of the first portion is attached to the waveguide, while a second end, opposite the first end, faces the optical interface. The first portion may taper as it extends from the first end to the second. The second portion of the coupler may be physically separated from both the first portion and the waveguide. However, in one embodiment, the first and second portions extend in the same direction towards the optical interface.