Abstract: A system for maintaining relative position of separate fibers is provided. The system comprises a fiber holder and fibers extending parallel along a Z-axis. The fibers include a first and second fiber, both having a coating and a core section. The fiber holder has a first and second alignment slots. The first alignment slot defines a first recess in a first surface of the fiber holder. The first recess is configured to receive the first fiber therein to provide frictional resistance to the first fiber. The second alignment slot defines a second recess in the first surface. The second recess is configured to receive the second fiber therein to provide frictional resistance to the second fiber. The first alignment slot is positioned in a fixed spaced apart manner from the second alignment slot to maintain at least a relative position of the first fiber and the second fiber.

Abstract: Disclosed herein is a fiber optic system including at least one fiber optic cable assembly having a multimode optical fiber for communication of an optical data signal at an operating wavelength and a devices having a single-mode fiber stub with a mode field diameter within 20% of the mode field diameter of the fundamental mode of the multimode optical fiber at the operating wavelength. The single-mode fiber stub is secured to a ferrule, and a center of a core of the single-mode fiber stub is within 0.5 ?m of a center of the ferrule. An end of the single-mode fiber stub that extends to or beyond the back end of the ferrule and forms an optical connection with the multimode optical fiber where the center of the single-mode fiber stub is within 2 ?m of a center of the multimode optical fiber.

Abstract: Disclosed herein are wavelength-division multiplexing devices using different angles of incidence (AOIs) at the WDM filters to provide for variable placement and orientation of WDM filters and channel ports, thereby decreasing the device footprint and allowing for shorter overall optical signal paths to increase signal performance and reliability. Also disclosed are stacked WDM filters for increased signal isolation.

Abstract: Disclosed herein are multi-layer wavelength-division multiplexing (WDM) devices that include a first optical signal router to route first demultiplexed signals from a common layer to a first channel layer and a second optical signal router to route second demultiplexed signals from the common layer to a second channel layer.

Abstract: The high-density FAU comprises a support substrate having a grooved front-end section that supports glass end sections of the small diameter low-attenuation optical fibers. A cover is disposed on the front-end section and secured thereto to hold the glass end sections in place. The substrate and the cover can be made of the same glass or glasses having about the same CTE. The glass end sections have a diameter d4 so that the pitch P2 of the fibers at the front end of the FAU can be equal to or greater than d4, wherein d4=2r4, with r4 being the radius of the glass end section as defined by the optical fiber cladding. The glass end section has a radius r4 less than 45 microns, allowing for a high-density FAU and a high-density optical interconnection device.

Abstract: A fiber array unit (FAU) includes a substrate, a cover element, and a plurality of optical fibers each including a splice joint connecting fibers of different mode-field diameters with a recoating material arranged over at least a portion of the fibers overlapping the substrate, wherein stripped portions of the fibers are arranged in grooves between the substrate and the cover element. A method for fabricating a compact FAU includes splicing ends of stripped sections of first and second optical fiber segments of different mode-field diameters, applying a recoating material over at least portions of the stripped sections, positioning portions of stripped sections of the second optical fiber segments in grooves defined in a substrate, and arranging a cover over the grooves. Certain embodiments include stripping recoating material portions of the second optical fiber segments before they are placed in the grooves.

Abstract: Disclosed herein is a wavelength-division multiplexing device with a unified passband. In particular, disclosed is a wavelength-division multiplexing (WDM) device with at least a common port, a channel port, and a WDM filter. The common port is configured for optical communication of a multiplexed signal to the WDM filter. A demultiplexed signal of the multiplexed signal includes a first secondary demultiplexed signal within a first wavelength range and a second secondary demultiplexed signal within a second wavelength range, which are separated from each other by a third wavelength range. The first WDM filter has a single unified passband including the first wavelength range, the second wavelength range, and the third wavelength range, such that the first WDM filter is configured to pass the first secondary demultiplexed signal and the second secondary demultiplexed signal to the first channel port.

Abstract: Disclosed herein are wavelength-division multiplexing devices using different angles of incidence (AOIs) at the WDM filters to provide for variable placement and orientation of WDM filters and channel ports, thereby decreasing the device footprint and allowing for shorter overall optical signal paths to increase signal performance and reliability. Also disclosed are stacked WDM filters for increased signal isolation.

Abstract: A fiber array unit (FAU) includes a substrate, a cover element, and a plurality of optical fibers each including a splice joint connecting fibers of different mode-field diameters with a recoating material arranged over at least a portion of the fibers overlapping the substrate, wherein stripped portions of the fibers are arranged in grooves between the substrate and the cover element. A method for fabricating a compact FAU includes splicing ends of stripped sections of first and second optical fiber segments of different mode-field diameters, applying a recoating material over at least portions of the stripped sections, positioning portions of stripped sections of the second optical fiber segments in grooves defined in a substrate, and arranging a cover over the grooves. Certain embodiments include stripping recoating material portions of the second optical fiber segments before they are placed in the grooves.

Abstract: A fiber array unit (FAU) connector includes a support substrate having a rear-end section and an elevated front-end section. The front-end section has a top surface with fiber grooves that support bare glass sections of optical fibers, which have respective fiber end faces that reside at a front end face defined by the front-end section. Two alignment pins reside in parallel alignment pin channels on opposite sides of the fiber grooves. The alignment pin channels terminate at respective front-end recessed surfaces that are axially spaced from the front end face. The alignment pins extend from the alignment pin channels to be even with the front end face. A cover secured to the front-end section holds the bare glass sections of the optical fibers and the alignment pins in place. Alignment sleeves are used to establish pin-to-pin alignment of confronting FAU connectors.

Abstract: The high-density FAU comprises a support substrate having a grooved front-end section that supports glass end sections of the small diameter low-attenuation optical fibers. A cover is disposed on the front-end section and secured thereto to hold the glass end sections in place. The substrate and the cover can be made of the same glass or glasses having about the same CTE. The glass end sections have a diameter d4 so that the pitch P2 of the fibers at the front end of the FAU can be equal to or greater than d4, wherein d4=2r4, with r4 being the radius of the glass end section as defined by the optical fiber cladding. The glass end section has a radius r4 less than 45 microns, allowing for a high-density FAU and a high-density optical interconnection device.

Abstract: Disclosed herein are multi-layer wavelength-division multiplexing (WDM) devices that include a first optical signal router to route first demultiplexed signals from a common layer to a first channel layer and a second optical signal router to route second demultiplexed signals from the common layer to a second channel layer.

Abstract: Disclosed herein is a wavelength-division multiplexing device with a unified passband. In particular, disclosed is a wavelength-division multiplexing (WDM) device with at least a common port, a channel port, and a WDM filter. The common port is configured for optical communication of a multiplexed signal to the WDM filter. A demultiplexed signal of the multiplexed signal includes a first secondary demultiplexed signal within a first wavelength range and a second secondary demultiplexed signal within a second wavelength range, which are separated from each other by a third wavelength range. The first WDM filter has a single unified passband including the first wavelength range, the second wavelength range, and the third wavelength range, such that the first WDM filter is configured to pass the first secondary demultiplexed signal and the second secondary demultiplexed signal to the first channel port.

Abstract: A polarization maintaining fiber array includes a substrate, a cover, and at least two polarization maintaining optical fibers. The substrate includes at least two main grooves, a first additional groove, and a second additional groove, wherein the main grooves are positioned between the first additional groove and the second additional groove. The fiber array includes at least two polarization maintaining optical fibers positioned in the at least two main grooves, a first dummy fiber positioned in the first additional groove, and a second dummy fiber positioned in the second additional groove. The cover is positioned such that it contacts the polarization maintaining optical fibers, the first dummy fiber, and the second dummy fiber.

Abstract: A polarization maintaining fiber array includes a substrate, a cover, and at least two polarization maintaining optical fibers. The substrate includes at least two main grooves, a first additional groove, and a second additional groove, wherein the main grooves are positioned between the first additional groove and the second additional groove. The fiber array includes at least two polarization maintaining optical fibers positioned in the at least two main grooves, a first dummy fiber positioned in the first additional groove, and a second dummy fiber positioned in the second additional groove. The cover is positioned such that it contacts the polarization maintaining optical fibers, the first dummy fiber, and the second dummy fiber.

Abstract: A wavelength-division multiplexing (WDM) optical assembly with multiple collimator sets is disclosed herein. The WDM optical assembly includes a WDM optical core subassembly including at least one optical signal router, at least one WDM filter, and a first and second WDM collimator sets. The first WDM collimator set includes a first common optical collimator and at least two channel collimators and the second WDM collimator set includes a second common optical collimator and at least two channel collimators. At least a portion of the first WDM collimator set is optically positioned on a first surface of at least one substrate, and at least a portion of the second WDM collimator set is optically positioned on a second surface of the at least one substrate opposite the first surface. The WDM optical core subassembly increases lane density while decreasing size and minimizing complexity by using a plurality of WDM common ports.

Abstract: Disclosed is a compact device for wavelength-division multiplexing applications. In particular, disclosed is a device that includes a housing and a core at least partially positioned within the housing. The core includes a first single fiber stub, a second single fiber stub, and at least one functional layer positioned between a first fiber of the first single fiber stub and a second fiber of the second single fiber stub. The at least one functional layer is configured to: (i) permit routing of a transmission signal of a multiplexed signal along an optical path from the first fiber stub to the second fiber stub, and (ii) prevent routing of a non-transmission signal of the multiplexed signal along the optical path from the first fiber stub to the second fiber stub. A distance between a first ferrule of the first fiber stub and a second ferrule of the second fiber stub is less than about 0.05 mm.

Abstract: Disclosed is a compact device for wavelength-division multiplexing applications. In particular, disclosed is a device that includes a housing and a core at least partially positioned within the housing. The core includes a first single fiber stub, a second single fiber stub, and at least one functional layer positioned between a first fiber of the first single fiber stub and a second fiber of the second single fiber stub. The at least one functional layer is configured to: (i) permit routing of a transmission signal of a multiplexed signal along an optical path from the first fiber stub to the second fiber stub, and (ii) prevent routing of a non-transmission signal of the multiplexed signal along the optical path from the first fiber stub to the second fiber stub. A distance between a first ferrule of the first fiber stub and a second ferrule of the second fiber stub is less than about 0.05 mm.

Abstract: Disclosed herein is a routing band-pass filter for routing optical signals between multiple optical channel sets. In particular, disclosed is a wavelength-division multiplexing (WDM) optical assembly including a first WDM filter, a second WDM filter, and a first routing filter. The first and second WDM filter are in communication with first and second sets of channel ports, respectively. The routing filter has a routing passband and forms a primary routing optical path for signals outside the routing passband between the first WDM filter and a common port. The routing filter also forms a secondary routing optical path for signals within the routing passband between the second WDM filter and the common port. The routing band-pass filter increases the number of channel ports in optical communication with a common port while maintaining signal integrity and increasing speed.

Abstract: Disclosed herein is a routing band-pass filter for routing optical signals between multiple optical channel sets. In particular, disclosed is a wavelength-division multiplexing (WDM) optical assembly including a first WDM filter, a second WDM filter, and a first routing filter. The first and second WDM filter are in communication with first and second sets of channel ports, respectively. The routing filter has a routing passband and forms a primary routing optical path for signals outside the routing passband between the first WDM filter and a common port. The routing filter also forms a secondary routing optical path for signals within the routing passband between the second WDM filter and the common port. The routing band-pass filter increases the number of channel ports in optical communication with a common port while maintaining signal integrity and increasing speed.