Abstract: An fiber-optic connector assembly includes a fiber optic ferrule and a connector, which engage an optical transceiver component. The fiber optic ferrule engages a mating plane of a lens array in the optical transceiver component and floats within the connector. The engagement of the assembly and the optical transceiver component may be removable rather than fixed. The fiber optic ferrule also engages a mechanical interface to account for three degrees of freedom, while the engagement of the mating surfaces account for another three degrees of freedom.

Abstract: Example embodiments provide a device that includes a rigid block body with a reservoir with two angled walls, a channel dug into a center axis of a bottom of the two angled walls, a stop wall at one end of the channel and an open end at a second end of the channel, a hole at a bottom portion of the stop wall, and a cut-out funnel shaped area on an opposite side of the stop wall from the channel, and the cut-out funnel shaped area funnels into the hole.

Abstract: An fiber-optic connector assembly includes a fiber optic ferrule and a connector, which engage an optical transceiver component. The fiber optic ferrule engages a mating plane of a lens array in the optical transceiver component and floats within the connector. The engagement of the assembly and the optical transceiver component may be removable rather than fixed. The fiber optic ferrule also engages a mechanical interface to account for three degrees of freedom, while the engagement of the mating surfaces account for another three degrees of freedom.

Abstract: An opto-mechanical coupler and corresponding method of manufacture are provided. The coupler may include a body defining a bottom surface, a receiving surface, and a reflective surface. The reflective surface may redirect optical signals between a first direction and a second direction. The receiving surface may position one or more optical fibers along the second direction such that an optical signal from the plurality of optoelectronic transceivers may be directed into the one or more optical fibers or an optical signal received from the one or more optical fibers may be directed into the plurality of the optoelectronic transceivers. The receiving surface may also define grooves to locate each optical fiber at a height relative to a first optical path in the second direction.

Abstract: An ophthalmic illumination system includes a light source generating a source light beam and a beam splitter splitting the source light beam into first and second light beams. A first attenuator is located in a path of the first light beam and a second attenuator is located in the path of the second light beam, the first and second attenuators operable to change the intensities of the first and second light beams, respectively. A first optical fiber port is configured for connection to a first optical fiber for delivering the first light beam to a patient's eye and a second optical fiber port is configured for connection to a second optical fiber for delivering the second light beam to the patient's eye. A control unit is communicatively coupled to the first and second attenuators and is operable to adjust the attenuators to control the intensities of the light beams delivered to the patient's eye.

Abstract: An opto-mechanical coupler and corresponding method are provided. The coupler may include a first end and a second end configured to receive optical fibers and a top surface and bottomed surface defining a through hole extending between the top and bottom surfaces. The coupler may include a reflective surface that redirects the optical signals between a first direction and a second direction substantially perpendicular to the first direction. The coupler may position one or more optical fibers along a second direction such that an optical signal from the plurality of optoelectronic transceivers is directed into one or more optical fibers or an optical signal from the one or more optical fibers is directed into a plurality of the optoelectronic transceivers, with the coupler accommodating different diameters of optical fiber including POF, SMF, and/or MMF fiber.

Abstract: An optical connector connectable to another optical connector includes an optical waveguide that includes a core, an attachment part to which the optical waveguide is attached, a lens part in which a positioning hole is formed, and a positioning pin that is provided on the attachment part and inserted through the positioning hole. The lens part and the attachment part are joined with the positioning pin being inserted into the positioning hole.

Abstract: This document discusses, among other things, a connector for an optical imaging probe that includes one or more optical fibers communicating light along the catheter. The device may use multiple sections for simpler manufacturing and ease of assembly during a medical procedure. Light energy to and from a distal minimally-invasive portion of the probe is coupled by the connector to external diagnostic or analytical instrumentation through an external instrumentation lead. Certain examples provide a self-aligning two-section optical catheter with beveled ends, which is formed by separating an optical cable assembly. Techniques for improving light coupling include using a lens between instrumentation lead and probe portions. Techniques for improving the mechanical alignment of a multi-optical fiber catheter include using a stop or a guide.

Abstract: A dynamic optical circulator device applicable to UPC-type and PC-type optical connectors is provided, including a first UPC/PC-type optical connector, a second UPC/PC-type optical connector, a third UPC/PC-type optical connector, a passive optical circulator, a reflected light detector and a transform element. The first, second and third UPC/PC-type optical connectors provide connections to optical fibers for receiving and transmitting optical signals. The first UPC/PC-type optical connector, the second UPC/PC-type optical connector and the third UPC/PC-type optical connector are connected to the three ports of the passive optical circulator, respectively, with the reflected light detector placed between the second UPC/PC-type optical connector and the second port of the passive optical circulator, while the transform element can be placed between any port of passive optical circulator and corresponding UPC-type and PC-type optical port.

Abstract: Beam couplers and splitters are disclosed herein. An example of a beam coupler and splitter includes a first waveguide having a first waveguide bevel and a bend, the first waveguide bevel to totally internally reflect at least some light incident thereon. A second waveguide includes a second waveguide bevel complementarily shaped to the first waveguide bevel, the second waveguide being coupled to the first waveguide such that i) the first waveguide bevel is offset from the second waveguide bevel so that a first portion of the first waveguide bevel is in direct contact with a first portion of the second waveguide bevel, a second portion of the first waveguide bevel is exposed, and a second portion of the second waveguide bevel is exposed, and ii) a predetermined coupling ratio is achieved.

Abstract: An optical branching element includes: an input waveguide; a tapered waveguide connected to the input waveguide; two branched waveguides that are connected to the tapered waveguide and arranged so as to form a Y-shape with the input waveguide and the tapered waveguide; and a plurality of strip-like waveguides that are provided so as to connect between the two branched waveguides and not to protrude outside the two branched waveguides, and formed so as to decrease in width as becoming distant from the tapered waveguide.

Abstract: Disclosed is a three-wavelength optical multiplexer which is compact, and which multiplexes light having different wavelength incident to three single-mode optical fibers, particularly light of red, green, and blue at transmittance above a certain reference.

Abstract: A photonic integrated circuit comprises a plurality of optical waveguides. Some waveguides cross some other waveguides at respective crossing locations. Some waveguides have varying widths wherein a width of a waveguide at a respective crossing location is smaller than the wavelength of the optical signal.

Abstract: Techniques for combining initially separate single mode and multimode optical beams into a single “Dual Mode” fiber optic have been developed. Bi-directional propagation of two beams that are differentiated only by their mode profiles (i.e., wavefront conditions) is provided. The beams can be different wavelengths and or contain different modulation information but still share a common aperture. This method allows the use of conventional micro optics and hybrid photonic packaging techniques to produce small rugged packages suitable for use in industrial or military environments.

Abstract: Beam couplers and splitters are disclosed herein. An embodiment of a beam coupler and splitter includes a first waveguide including a bevel and a bend, and a second waveguide including a bevel complementarily shaped to the first waveguide bevel. The first waveguide bevel is configured to totally internally reflect at least some light incident thereon. The second waveguide is coupled to the first waveguide such that i) the second waveguide bevel is adjacent to at least a portion of the first waveguide bevel, and ii) a predetermined coupling ratio is achieved.

Abstract: An optical bus. Optical sub-assemblies are used to connect lengths of optical fiber to form a single optical fiber that is a bus. A master transceiver may be connected to one end of the fiber and nodes can be connected to the optical sub-assemblies. Each optical sub-assembly includes a center fiber with a mirror that enables each connector to reflect optical signals out of the fiber and that enables a node to launch optical signals on the optical bus. The optical bus can also be connected with a second transceiver that may be used to deliver optical power to the attached nodes. Some nodes include two optical subassemblies to enable bidirectional communication on the optical bus.

Abstract: An innovative micro-size photonic switch is presented. The photonic switch is comprised of: a mirror having a reflecting surface; an input waveguide; and an output tapered waveguide structure. The photonic switch further includes a switching mechanism disposed adjacent to the reflecting surface and operable to change the refractive index along the reflective surface and thereby shift the angle at which the optical signal reflects from the mirror. More specifically, the switching mechanism may operate to change concentration of free carrier distribution along the reflective surface and thereby displace the effective reflecting interface of the mirror. In this way, the optical signal can be directed to one of two or more output ports of the output tapered waveguide structure and finally exited by one output waveguide channel that is connected to the selected port of the output tapered waveguide structure.

Abstract: The present invention provides an optical branching device and an optical communication system which are easy to connect with optical fibers. In the optical branching device, when light emitted from an optical fiber in a front stage is incident on an entrance port of a multicore optical fiber, the light propagates through a first core and then is distributed from the first core to four second cores by core-to-core crosstalk between the first and second cores. The light beams distributed to the four second cores propagate through the respective cores and are emitted to four optical waveguides optically coupled core-to-core thereto within a fan-out part at exit ports.

Abstract: Optical elements (light sources 16 or photodetectors 18) are arranged in a two-dimensional array, and the relative positional relationship between the optical elements and optical waveguides 12 is defined such that optical waveguides 12 extend between the optical elements in the two-dimensional array substantially parallel to substrate 19 for increased parallelism. Micromirrors 15 are disposed in respective optical waveguides 12 to bend light beams through 90 degrees to realize a highly efficient optical coupling between the optical elements and optical waveguides 12. The optical waveguides are stacked in multiple stages, and light beams are lead to the optical waveguides in the multiple stacks through micromirrors 15 across the stacked plane of the optical waveguides, thereby realizing parallel connection between the two-dimensional array of optical elements and a two-dimensional array of optical waveguides.

Abstract: A waveguide stub is connected to a pillar-type square-lattice photonic crystal waveguide. Within the waveguide stub, the diameter of a defect is made larger than that of the original photonic crystal waveguide thereby reducing the group velocity of a guided light. The original waveguide and the waveguide stub are smoothly connected via a taper waveguide. Because of low group velocity of light in the waveguide stub, free spectral range (FSR) decreases thereby allowing the size of the waveguide stub to be reduced.

Abstract: An optical bus. Optical sub-assemblies are used to connect lengths of optical fiber to form a single optical fiber that is a bus. A master transceiver may be connected to one end of the fiber and nodes can be connected to the optical sub-assemblies. Each optical sub-assembly includes a center fiber with a mirror that enables each connector to reflect optical signals out of the fiber and that enables a node to launch optical signals on the optical bus. The optical bus can also be connected with a second transceiver that may be used to deliver optical power to the attached nodes. Some nodes include two optical subassemblies to enable bidirectional communication on the optical bus.

Abstract: A mirror-embedded light transmission medium according to the present invention comprises: a light transmission medium including a light transmission layer, light being transmitted through the light transmission layer; a rough surface which terminates the light transmission layer, a direction of the rough surface being parallel or oblique to a light transmission direction of the light transmission layer; a reflection enhancing layer that adherently covers the rough surface; and a smooth surface formed over the reflection enhancing layer, the smooth surface reflecting the light transmitted through the light transmission layer.

Abstract: This document discusses, among other things, a connector for an optical imaging probe that includes one or more optical fibers communicating light along the catheter. The device may use multiple sections for simpler manufacturing and ease of assembly during a medical procedure. Light energy to and from a distal minimally-invasive portion of the probe is coupled by the connector to external diagnostic or analytical instrumentation through an external instrumentation lead. Certain examples provide a self-aligning two-section optical catheter with beveled ends, which is formed by separating an optical cable assembly. Techniques for improving light coupling include using a lens between instrumentation lead and probe portions. Techniques for improving the mechanical alignment of a multi-optical fiber catheter include using a stop or a guide.

Abstract: An optical-path turning device is interposed between paired first and second optical components of pin-fitting alignment system that have their optical paths mutually different in direction, for an optic coupling between the optical components, and has a device body 16 of a block shape.

Abstract: An analytical cell including a lightguide with a plurality of conduits filled with a migration medium. The medium, the lightguide and a surrounding medium have refractive indices selected such that light entering the lightguide is internally reflected within the lightguide to provide substantially uniform illumination of the conduits.

Abstract: A system and methods for dividing an optical beam in a hollow metallized waveguide are disclosed. The method includes directing an optical signal into a first section of a hollow metallized waveguide. The optical signal is adiabatically expanded in a second section of the hollow metallized waveguide coupled to the first section. The optical signal is split with an in-plane optical beam splitter located in a third section of the hollow metallized waveguide coupled to the second section.

Abstract: A double clad fiber includes a core, a first cladding provided so as to cover the core, and a second cladding provided so as to cover the first cladding. The second cladding has a plurality of pores extending in a length direction and arranged so as to surround the first cladding. In at least one fiber end, the second cladding has been removed by mechanical processing so that the at least one fiber end is formed by the core and the first cladding.

Abstract: An optical apparatus including a 360-degree star coupler with derivative structure(s) and applications to optical imaging, optical communications and optical spectroscopy.

Abstract: A miniature mechanical transfer (MT) optical coupler (“MMTOC”) for optically connecting a first plurality of optical fibers with at least one other plurality of optical fibers. The MMTOC may comprise a beam splitting element, a plurality of collimating lenses, and a plurality of alignment elements. The MMTOC may optically couple a first plurality of fibers disposed in a plurality of ferrules of a first MT connector with a second plurality of fibers disposed in a plurality of ferrules of a second MT connector and a third plurality of fibers disposed in a plurality of ferrules of a third MT connector. The beam splitting element may allow a portion of each beam of light from the first plurality of fibers to pass through to the second plurality of fibers and simultaneously reflect another portion of each beam of light from the first plurality of fibers to the third plurality of fibers.

Abstract: Provided is an optical device, which includes a substrate, a first cladding disposed on the substrate, a first optical waveguide extended in a first direction on the first cladding, and having a first refractive index, a side grating formed in at least one side of the first optical waveguide, a second optical waveguide filling a space of the side grating, extended in a second direction across the first direction on the first cladding, and having a second refractive index, and a second cladding disposed on the second optical waveguide, and having a third refractive index, wherein the first refractive index is greater than the second refractive index, and the second refractive index is greater than the third refractive index.

Abstract: An improved laser source for use in a distributed temperature sensing (DTS) system (and DTS systems employing the same) includes a laser device and drive circuitry that cooperate to emit an optical pulse train at a characteristic wavelength between 1050 nm and 1090 nm. An optical amplifier, which is operably coupled to the laser device, is adapted to amplify the optical pulse train for output over the optical fiber sensor of the DTS system. In the preferred embodiment, the laser device operates at 1064 nm and outputs the optical pulse train via an optical fiber pigtail that is integral to its housing. The optical power of the optical pulse train generated by the laser source is greater than 100 mW, and preferably greater than 1 W, at a preferred pulse repetition frequency range between 1 and 50 kHz, and at a preferred pulse width range between 2 and 100 ns.

Abstract: This document discusses, among other things, a connector for an optical imaging probe that includes one or more optical fibers communicating light along the catheter. The device may use multiple sections for simpler manufacturing and ease of assembly during a medical procedure. Light energy to and from a distal minimally-invasive portion of the probe is coupled by the connector to external diagnostic or analytical instrumentation through an external instrumentation lead. Certain examples provide a self-aligning two-section optical catheter with beveled ends, which is formed by separating an optical cable assembly. Techniques for improving light coupling include using a lens between instrumentation lead and probe portions. Techniques for improving the mechanical alignment of a multi-optical fiber catheter include using a stop or a guide.

Abstract: An optical component including an acceptance fiber, e.g. a photonic crystal fiber, for propagation of pump and signal light, a number of pump delivery fibers and a reflector element that reflects pump light from the pump delivery fibers into the acceptance fiber. An optical component includes a) a first fiber having a pump core with an NA1, and a first fiber end; b) a number of second fibers surrounding the pump core of the first fiber, at least one of the second fibers has a pump core with an NA2 that is smaller than NA1, the number of second fibers each having a second fiber end; and c) a reflector element having an end-facet with a predetermined profile for reflecting light from at least one of the second fiber ends into the pump core of the first fiber.

Abstract: A method of manufacturing an optical device involves forming patterns on a dielectric substrate. The patterns include a waveguide pattern having a folded part, a conductor pattern positioned on an outer peripheral side of the folded part, and a dummy pattern that connects the folded part and the conductor pattern. The method further involves performing heat diffusion processing on the dielectric substrate on which the patterns have been formed at the forming, to make the waveguide pattern into an optical waveguide.

Abstract: A photonic crystal is configured with wavelength converting material to act as a concentrator for electromagnetic energy. The concentrator may also be configured with energy conversion devices to convert the electromagnetic energy into another form of energy.

Abstract: Fiber optic sensors commonly require a 180 degree turnaround to form a continuous optical circuit. Methods and apparatus for providing 180 degree turnarounds in a fiber optic system that include a shorter radius turnaround then provided by micro-bending the optic fiber are desired. An embodiment of a turnaround apparatus includes a first optic fiber pigtail, a second optic fiber pigtail, and an optical waveguide forming a U-shaped path having an input end optically connected to a first end of the first pigtail and an output end optically connected to a first end of the second pigtail.

Abstract: The present invention is a method and an apparatus for tuning an optical delay line. In one embodiment, an optical delay line includes at least one ring resonator in which light is guided or is confined and at least one heater positioned laterally from the ring resonator. The heater produces heat in a localized area, allowing for the tuning of individual delay elements with minimal crosstalk.

Abstract: Structural joint strain monitoring apparatus 92 comprises jacket means 52 in the form of first and second jacket elements 62, each having a primary jacket part 62a and substantially perpendicular secondary jacket part 62b which together define a compartment for receiving a joint, between two pipes 54, 56, to be monitored. The jacket means 52 additionally comprises two primary web elements 76, 78 provided between the primary and secondary jacket parts 62a, 62b. Three fiber Bragg grating (FBG) strain sensors 96, 98, 100 and an FBG temperature sensor 102 are provided within an optical fiber 104, bonded to the primary web elements 76, 78 and each end of the second jacket element 62 respectively, for measuring strain or temperature at their respective locations. The FBG sensors 96, 98, 100, 102 are optically coupled, via optical fiber 104, to optical fiber sensor interrogation apparatus 94, operable to interrogate each FBG sensor.

Abstract: An optical resonator includes an optical waveguide with a core surrounded by a clad of lower refractive index. The optical waveguide includes a non-terminated ring-type optical waveguide for resonant propagation of light and an input-output optical waveguide, unitarily coupled to the ring-type optical waveguide, for output of light from the ring-type optical waveguide, or input of light to and output of light from the optical ring waveguide. The ring-type optical waveguide and input-output optical waveguide can be formed simultaneously as silicon-wire waveguides. The unitary coupling simplifies fabrication of the optical resonator.

Abstract: An optical communication module includes a base substrate; a wavelength branching filter arranged on the base substrate, in which a light is allowed to go through or be reflected according to a wavelength thereof; a photodetector arranged on the base substrate to receive a light passed through the wavelength branching filter and to convert the light into an electric signal; and a light emitting device arranged on the base substrate to provide a transmission light. The transmission light is outputted through the wavelength branching filter. The optical detector comprises a light receiving portion which is formed to have a first length and a second length, which is shorter than the first length. The first length of the light receiving portion is perpendicular to an optical axis of an input light on a plane parallel to a surface of the substrate, and a second length of the light receiving portion is parallel to the optical axis of the input light.

Abstract: The present invention provides a system, method and apparatus for improved electrical-to-optical transmitters (100) disposed within printed circuit boards (104). The heat sink (110, 200) is a thermal conductive material disposed within a cavity (102) of the printed circuit board (104) and is thermally coupled to a bottom surface (112) of the electrical-to-optical transmitter (100). A portion of the thermal conductive material extends approximately to an outer surface (120, 122 or 124) of a layer (114, 116 or 118) of the printed circuit board (104). The printed circuit board may comprise a planarized signal communications system or an optoelectronic signal communications system. In addition, the present invention provides a method for fabricating the heat sink wherein the electrical-to-optical transmitter disposed within a cavity of the printed circuit board is fabricated. New methods for flexible waveguides and micro-mirror couplers are also provided.

Abstract: A photonic crystal is configured with wavelength converting material to act as a concentrator for electromagnetic energy. The concentrator may also be configured with energy conversion devices to convert the electromagnetic energy into another form of energy.

Abstract: Embodiments of the present invention provide a current sensing device. The current sensing device includes, inter alia, a three-by-three (3×3) optical coupler made of polarization-maintaining (PM) fibers and thus being a PM fiber coupler; a light source and at least one photon-detector connected to a first side of the 3×3 PM fiber coupler; and a fiber coil connected to a second side of the 3×3 PM fiber coupler. The 3×3 PM fiber coupler is adapted to split an input light from the light source into first and second optical signals while maintaining their respective polarization directions; and is adapted to cause coherent interference of third and fourth optical signals, related respectively to the first and second optical signals and received from the fiber coil.

Abstract: A system and methods for routing optical signals are disclosed. The system includes a first large core hollow waveguide having a reflective coating covering an interior of the waveguide and configured to guide a substantially collimated multi-mode coherent light beam. A second large core hollow waveguide with an interior reflective coating is coupled to the first waveguide with a coupling device. The coupling device is configured to redirect at least a portion of the coherent light beam from the first to the second waveguides through an optical path that is sufficiently short that a beam walk-off of the coherent light through the coupling device is less than half a width of the first large core hollow waveguide.

Abstract: The invention relates to a method and a device for coupling fiber optic cables. Said device comprises at least one module, which is equipped with at least one retaining unit for retaining at least two cassettes. The invention is characterized in that: a cassette is configured with at least one coupling element; at least one strand bundle can be fixed to the module, whereby said strand bundle can be split into at least two strands comprising at least one fiber optic cable; an excess length of strand can be retained by a cassette, the fiber optic cable or cables being connected to the coupling element and the cassette together with its retained strand being detachably connected to the retaining unit.

Abstract: The present invention provides a system, method and apparatus for improved electrical-to-optical transmitters (100) disposed within printed circuit boards (104). The heat sink (110, 200) is a thermal conductive material disposed within a cavity (102) of the printed circuit board (104) and is thermally coupled to a bottom surface (112) of the electrical-to-optical transmitter (100). A portion of the thermal conductive material extends approximately to an outer surface (120, 122 or 124) of a layer (114, 116 or 118) of the printed circuit board (104). The printed circuit board may comprise a planarized signal communications system or an optoelectronic signal communications system. In addition, the present invention provides a method for fabricating the heat sink wherein the electrical-to-optical transmitter disposed within a cavity of the printed circuit board is fabricated. New methods for flexible waveguides and micro-mirror couplers are also provided.

Abstract: The present invention provides a system, method and apparatus for improved electrical-to-optical transmitters (100) disposed within printed circuit boards (104). The heat sink (110, 200) is a thermal conductive material disposed within a cavity (102) of the printed circuit board (104) and is thermally coupled to a bottom surface (112) of the electrical-to-optical transmitter (100). A portion of the thermal conductive material extends approximately to an outer surface (120, 122 or 124) of a layer (114, 116 or 118) of the printed circuit board (104). The printed circuit board may comprise a planarized signal communications system or an optoelectronic signal communications system. In addition, the present invention provides a method for fabricating the heat sink wherein the electrical-to-optical transmitter disposed within a cavity of the printed circuit board is fabricated. New methods for flexible waveguides and micro-mirror couplers are also provided.

Abstract: An optical cavity structure for bending optical signals is provided. The optical cavity structure includes an input port for receiving input optical signals from a first waveguide. The optical cavity structure also includes an interconnecting structure that receives said input optical signals and interconnects said first waveguide to a second waveguide, the interconnecting structure further includes at least four straight edges that orthogonal and of a finite width. The optical cavity structure further includes an output port coupled to the interconnecting structure for providing the second waveguide with the input optical signals. Further, the optical cavity structure may be used to create three dimensional splitter devices and resonators.

Abstract: A photoelectronic device capable of maintaining the degree of freedom in designing for dealing with design changes and responding to producing a variety of kinds in a small amount, and the production method are provided: wherein a light emitting element for emitting a light to be a clock signal, a semiconductor chip provided with light receiving portions for receiving the light, and an optical waveguide sheet formed to be a sheet, wherein an outer circumference of a core is covered with a clad, adhered to said semiconductor chip are provided; and the optical waveguide sheet is configured to be irradiated at a light incident portion of a core with a light from the light emitting element and includes one or more T-shaped branch having a vertical opening portion having a vertical inner wall, which is vertical with respect to the direction within a surface of the optical waveguide sheet and becomes a mirror surface for dividing and reflecting the light, and a sloping opening portion having a sloping inner wall, w

Abstract: A 1×2 splitter design having low loss is described. The splitter has a non-adiabatic tapered waveguide (22) connected between a substantially single-mode input waveguide (20) and two output waveguides (24, 26). The non-adiabatic tapered waveguide widens in width towards the output waveguide, and merges substantially continuously with the input waveguide in a direction parallel to the optical axis of the input waveguide. This keeps radiation mode generation to a minimum which, in turn, keeps insertion loss low. In the described embodiment, the non-adiabatic taper shape is based on a perturbed cosine function. The 1×2 splitter can be cascaded with other such splitters in order to build a 1×2N splitter design.