The present disclosure generally relates to optical connections and, more particularly, to waveguide connector assemblies having a waveguide substrate with a plurality of waveguides.
In optical communication networks, optical fibers may be routed from a junction point to a plurality of individual subscribers, such as residences, businesses, data center servers, and the like. Thus, an enclosure may be used to receive a plurality of optical fibers, and then provide optical connections to route individual optical fibers to individual subscribers. As an example, a multi-fiber connector may be provided as an input to an enclosure. A plurality of output optical connectors may also be provided at the enclosure. The output optical connectors are routed to individual subscribers. Optical paths within the enclosure route the optical signals from the multi-fiber connector to the output connectors to provide optical signals to and from the individual subscribers. Typically, the optical signals are routed within the enclosure by optical fibers. However, the management and organization of many optical fibers within the enclosure may be challenging. Further, the presence of many optical fibers may require the enclosure to be large and bulky.
In one embodiment, a waveguide module assembly includes a first shell housing, and a second shell housing coupled to the first shell housing. The first shell housing and the second shell housing define a cavity. The waveguide module assembly further includes a waveguide substrate including at least one waveguide, a first surface, and a second surface opposite the first surface. The waveguide substrate is at least partially disposed within the cavity such that at least a portion of the first surface and at least a portion of the second surface are covered by at least one of the first shell housing and the second shell housing.
In another embodiment, a waveguide module assembly for receiving optical connectors includes a first shell housing and a second shell housing coupled to the first shell housing. The first shell housing and the second shell housing define, a cavity, at least one input connector opening for receiving an input connector, and at least one output connector opening for receiving an output connector. The waveguide module assembly further includes a waveguide substrate having at least one waveguide, a first surface, and a second surface opposite the first surface. The waveguide substrate is at least partially disposed within the cavity.
In another embodiment, a waveguide module assembly for receiving optical connectors includes a first shell housing having a first cavity portion, and a second shell housing coupled to the first shell housing. The second shell housing has a second cavity portion, and the first cavity portion and the second cavity portion define a cavity when the first shell housing is mated to the second shell housing. The waveguide module assembly further includes a waveguide substrate having at least one waveguide, a first surface, and a second surface opposite the first surface. The waveguide substrate is at least partially disposed within the cavity when the first shell housing is positioned over the first surface of the waveguide substrate and the second shell housing is positioned over the second surface of the waveguide substrate.
In another embodiment, a waveguide module assembly for receiving optical connectors includes a first shell housing having a first cavity slot, and a second shell housing coupled to the first shell housing. The second shell housing has a second cavity slot, and the first cavity slot and the second cavity slot define a cavity. The waveguide module assembly further includes a waveguide substrate having at least one waveguide, a first surface, and a second surface opposite the first surface. The waveguide substrate is at least partially disposed within the cavity.
In another embodiment, a method of assembling a waveguide module assembly, includes positioning a waveguide substrate into a cavity defined by a first shell housing coupled to a second shell housing. The waveguide substrate includes at least one waveguide, a first surface and a second surface. The waveguide substrate is at least partially disposed within the cavity such that at least a portion of the first surface and at least a portion of the second surface are covered by at least one of the first shell housing and the second shell housing.
It is to be understood that both the foregoing general description and the following detailed description are merely exemplary, and are intended to provide an overview or framework to understanding the nature and character of the claims. The accompanying drawings are included to provide a further understanding, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments, and together with the description serve to explain principles and operation of the various embodiments.
Embodiments described herein are directed to waveguide substrate connector assemblies that route optical signals by a plurality of waveguides within the waveguide substrate. Optical communication networks are used to provide data to a plurality of subscribers. Optical fibers are thus routed to individual subscribers, such as businesses, residences, data center servers, and the like. In some cases, optical fibers of a multi-fiber optical cable are individually routed to individual subscribers. For instance, it may be desirable to break-out traffic from a multifiber optical cable into smaller subsets of one or more optical fibers for routing the optical signals toward the desired location in the optical network. Thus, space-efficient means for routing optical signals of a multi-fiber optical connector between different, individual locations (e.g., individual subscribers) are desired. For example, individual optical fibers optically coupled to one or more multi-fiber optical connectors may be routed within a communication enclosure, and then routed to individual destinations from the enclosure. However, fiber-management of the many optical fibers within the enclosure may become unwieldy, and may require a large enclosure.
Embodiments of the present disclosure are directed to waveguide connector assemblies that include a waveguide substrate having waveguides that may replace the optical fibers within the enclosure, thereby reducing the size and cost of the enclosure. As a non-limiting example, the embodiments of the present disclosure enable the use of existing connectors while interfacing with a waveguide substrate having written waveguides within an enclosure. The module may serve as an exit point for a subscriber drop, with some optical signals “passing through,” or the enclosure may serve as a shuffle, reorienting and redirecting waveguides into new arrangements, or for wavelength division multiplexing, etc. It should be understood that other uses for the waveguide substrates described herein are possible.
Further, the waveguide connector assemblies described herein include a robust shell housing that surrounds and protects the waveguide substrate within a cavity. The concepts disclosed herein may be used with waveguide substrates having any suitable wiring scheme. The concepts of waveguide substrates may be used as a replacement for the large and bulky modules or enclosures that physically route optical fibers within a box. The concepts disclosed are advantageous since they can take less space than conventional modules or enclosures, thereby improving density. Additionally, the waveguide substrates allow adaptability for moves, adds and changes to the optical network.
As described in more detail below, embodiments provide for easy and fast assembly time and therefore an inexpensive manufacturing process. The parts are designed to snap together with the precision needed for the application. Further the waveguide connector assemblies described herein have a low cost, simplified bill of materials. A single overmolding step with coarse precision is used for connector receptacle recesses, package substrate and cover, and, in some embodiments additional alignment pins and latches. In some embodiments, no additional adhesives are needed, which prevents potential reliability issues associated with long-term creep, shrinkage and thermal degradation of the adhesive.
The waveguides within the waveguide substrates described herein may be fabricated by a laser-writing process wherein a short pulsed laser is used to create three dimensional waveguides within the material of the waveguide substrate (e.g., glass material). A short pulse (sub-picosecond) laser tightly focused into the waveguide substrate changes the material structure and locally raises the refractive index. By controlling the laser position (e.g., via translation stages), these waveguides can be created anywhere within the waveguide substrate. Further, by controlling the laser power and scan speed, single mode waveguides of low optical loss are possible.
The waveguides may extend from one edge of the waveguide substrate to another. However, waveguides at the end of the waveguide substrate may necessitate effective interconnects to transfer a signal in a waveguide into an optical fiber where it may be routed to a new destination. Embodiments of the present disclosure provide component parts and integral features for optically connecting waveguides to optical fibers within input and output optical connectors. One or more engagement and/or alignment features may be provided on edges and/or surfaces of the waveguide substrate that mate with corresponding engagement and/or alignment features of one or more optical connectors.
Alignment features on the glass sheet may include coarse alignment features and fine alignment features, both cooperating to allow a passive alignment of, for example, an LC connector and an MT-style connector to an edge of the waveguide substrate. Such coarse alignment features may include, but are not limited to, cuts in the shape of a “V” that extend from a top surface to a bottom surface of the waveguide, effectively “notching” the edge of the waveguide substrate. Corresponding features on a shell housing engage the coarse alignment features to bring engagement paths for a fiber optic connector to within axial proximity of the waveguides of the waveguide substrate. Pin bores and other features may also be fabricated on the edges of the waveguide substrate. “Float,” or rather built-in freedom of movement, allows for fine alignment as in the manner of mating two optical connectors, e.g., guide pins and split sleeves.
These alignment and/or engagement features may be fabricated into the waveguide substrates described herein by a laser-damage-and-etch process. When the laser power is increased, the material (e.g., glass) of the waveguide substrate becomes damaged such that subsequent exposure to chemical etchant causes a high selective anisotropic etching in the regions exposed to the laser. Because the etch rate of the material is higher at the regions damaged by the laser than regions not damaged by the laser, this process may be used to create alignment and/or engagement features for attaching fibers.
Referring now to
As the waveguide substrate 10 routes signals of light, it may be referred to as a photonic integrated circuit (PIC).
The example waveguide substrate 10 has four waveguides 17, although it should be understood that any number of waveguides may be provided in one or multi-dimensional arrays. Each waveguide 17 is defined by a line on or within the waveguide substrate 10 having a refractive index that is different from the material outside of the waveguide 17 such that light is maintained within the waveguide 17 when propagating through the waveguide substrate 10. Any known or yet-to-be-developed methods of writing waveguides 17 into the waveguide substrate 10 may be utilized. For example, an ion-exchange process may be used to write the plurality of waveguides 17 by using a mask to change the refractive index of the material along lines defining the desired plurality of waveguides 17. As another example, a pulsed laser may be applied to apply two-dimensional or three-dimensional waveguides 17 within a bulk of the waveguide substrate 10. The waveguide index of refraction profile may be step index (i.e., uniform) or graded in the direction perpendicular to the waveguide core axis which is also the direction of light propagation.
In the illustrated example, input ends of the plurality of waveguides 17 are relatively closely spaced (i.e., have a small pitch between the waveguides) at an input 12 on the input edge 18, and branch out to be relatively largely spaced (i.e., have a large pitch as compared to the pitch at the input edge 18) at outputs 14. As a non-limiting example, and described in detail below, the input 12 may be configured to receive a MTP or MTO multiple fiber optical connector, while the outputs 14 may be configured to receive multiple SC or LC single fiber connectors. As a non-limiting example, pairs of outputs 14 may be configured to receive a duplex LC connector.
As shown in
Still referring to
The input alignment features and the output alignment features may be fabricated by a laser damage and etch process. A pulsed laser beam may be applied to regions of the input edge 18 and the output edge 19 at the desired locations of the alignment features. The pulsed laser beam modifies the material of the waveguide substrate 10. The waveguide substrate 10 is then subjected to an etching solution to etch away the damaged regions to form the desired alignment features, as well as any other features. The etch rate of the damaged regions is greater than the etch rate of the material outside of the damaged regions. Therefore, the etching solution forms the desired features of the waveguide substrate 10.
It may be desirable to use the same laser used to form the plurality of waveguides 17 as the desired features, such as the alignment features. In this manner, the alignment features may be precisely registered to the plurality of waveguides 17. For example, one or more waveguides 17 may be first written into the waveguide substrate 10 by a laser. Then, the same laser may be used to damage the waveguide substrate 10 in regions corresponding with desired alignment features by referencing one or more regions of the one or more waveguides 17 as alignment reference fiducials. Similarly, the damaged regions corresponding to the alignment features may be first formed by the laser and then used as one or more reference fiducials to write the one or more waveguides.
It should be understood that the configuration of the waveguide substrates described herein may take on other configurations. For example, any number of waveguides may be provided, and embodiments are not limited to the branching out (i.e., fanning out) configuration shown in
By way of explanation, the waveguide substrate 10 may break-out of waveguides from a larger grouping such as 8, 12, 24, 36, 48, etc. waveguides at the input to smaller subsets such as 2, 4, 8, 12, etc. at the output. The break-out of optical signals from a large connection point to smaller connection points allows the routing of optical signals toward different locations in the optical network. For instance, breakouts may also allow for the management of transmit-receive pairs for duplex transmission or groupings of transmit and receive channels for parallel transmission applications.
Additional example configurations for waveguide substrates that may be provided in the shell housings described herein are provided in U.S. Pat. Appl. Nos. PCT/US19/25295 filed on Apr. 2, 2019 and PCT/US19/25294 filed on Apr. 2, 2019, which are hereby incorporated by reference in their entireties.
Referring now to
The waveguide module assembly 100 generally includes the waveguide substrate 10 and a clamshell housing 101 comprising a first shell housing 110 and a second shell housing 120. As described in more detail below, the clamshell housings described herein define a cavity in which the waveguide substrate 10 is disposed. At least a portion of the first surface 11 and the second surface 20 of the waveguide substrate are covered by first shell housing 110 and the second shell housing 120, respectively.
Referring to
The first and second shell housings 110, 120 are brought together as indicated by arrows A and B such that the waveguide substrate 10 is disposed therebetween. Particularly, the first cavity portion 116 and the second cavity portion 126 cooperate to form a cavity 136 of the clamshell housing 101 where the waveguide substrate 10 is disposed (
As shown in
The at least one first output connector recess 114 and the at least one second output connector recess 124 cooperate to form at least one output connector opening 134. Although
Referring now to
Coarse alignment between the input optical connector 140 and the waveguides 17 is provided by features of the body 141 of the input optical connector 140 and features of the interior surfaces defining the input connector opening 132. Fine alignment between the optical fibers of the input optical connector 140 and the waveguides 17 is provided by insertion of the alignment pins 142 of the input optical connector 140 into the first pin bore 13A and the second pin bore 13B of the waveguide substrate 10. In other embodiments, no alignment pins or pin bores are provided. Rather, alignment is achieved by other features, such as features integrated into the body 141 of the input optical connector 140 and/or features integrated into the input connector opening 132.
The output connector opening 134 is shaped and configured to receive an output optical connector 145. In the illustrated embodiment, the output optical connector 145 is a single fiber optical connector, such as a SC optical connector, or a duplex optical connector having two connector bodies each maintaining an optical fiber (not shown), such as a LC duplex optical connector. The output optical connector 145 may be any suitable optical connector. The optical fiber within an output connector body 147 is optically coupled to an individual waveguide 17 at an output 14 of the waveguide substrate 10 (
Fine alignment between the optical fiber of the output optical connector 145 and a waveguide 17 at the output 14 of the waveguide substrate 10 is provided by the interaction between the central positive feature 15 (which acts as a ferrule of the waveguide substrate 10) and a ferrule 146 of the output optical connector 145. The optical fiber (not shown) of the output optical connector 145 is disposed within the ferrule 146 and terminates at the end face of the ferrule 146. During mating the end face of the ferrule 146 of the output optical connector 145 abuts the end face of the central positive feature 15 such that the individual waveguide 17 is optically coupled to the optical fiber of the output optical connector 145. Although not shown in
The first and second shell housings 110, 120 may be made of any suitable material that will protect the waveguide substrate 10 from environmental damage or damage due to handling. As a non-limiting example, one or both of the first and second shell housings 110, 120 may be made of a transparent material, such as a transparent polymer, that allows the waveguide substrate 10 to be visually inspected for troubleshooting purposes. The transparent material described herein is transmissive to optical radiation in the visible spectrum such that the waveguide substrate is at least partially visible to an observer.
The first shell housing 110 may be secured to the second shell housing 120 by a variety of means. As an example, the first shell housing 110 may be permanently secured to the second shell housing 120, such as by an adhesive. In other embodiments, the first shell housing 110 and the second shell housing 120 are removably secured to one another. In one non-limiting example shown in
In the embodiment illustrated by
In the embodiment of
The second shell housing 120″ includes female alignment features configured as bores 158 wherein a lower, base diameter db is larger than an opening diameter do such that the tabs 159 are compressed inwards upon insertion of the pins 157 into the opening of the bores 158 until the tabs 159 reach the larger diameter base, where they then spring outward allowing the first shell housing 110″ to be secured to the second shell housing 120″.
Embodiments described herein may have a clamshell housing that attached from the left and right rather from top to bottom as illustrated in
As shown in
In the illustrated example, the first shell housing 210 defines at least one input connector opening 232 for receiving at least one input optical connector, and the second shell housing 220 defines at least one output connector opening 234 for receiving at least one output optical connector. Unlike the embodiments of
The first shell housing 210 may be coupled to the second shell housing 220 by a variety of methods. In the illustrated embodiment, the first shell housing 210 has an end 255 that mates with and engages and end 256 of the second shell housing 220. The end 255 of the first shell housing 210 has an engagement feature configured as latching arms 257. The end 256 of the second shell housing 220 has grooves 258 that receive the latching arms 257. The latching arms 257 and the walls defining the grooves 258 are tapered to enable the latching arms to slide into and out of the grooves 258 so that the first shell housing 210 may be detached from the second shell housing 220. For example, when the end 255 of the first shell housing 210 contacts the end 256 of the second shell housing, the tapered surface allows for the latching arms 257 to flex outwardly until they reach the grooves 258, where then then snap back and are seated in the grooves 258.
Referring now to
The clamshell shell housings described above completely enclose the waveguide substrate 10. However, in some embodiments, the clamshell shell housing may be designed to simply wrap around the waveguide substrate on the two connector edges (i.e., the input edge 18 and the output edge 19) leaving some side portions of the waveguide substrate exposed and uncovered.
In some embodiments, the cavity defined by the clamshell housing is larger than the waveguide substrate in at least one of the X-axis and the Y-axis to allow lateral movement of the waveguide substrate in one or two lateral directions. Freedom of the waveguide substrate to float within the clamshell housing may allow for more precise alignment of the input optical connectors and the output optical connectors with respect to the waveguide substrate because tolerance errors of the first and second shell housings and/or the bodies of the optical connectors will not contribute to misalignment. Rather, the waveguide substrate may move to be precisely positioned due to the fine alignment of the alignment pin and bores with respect to the input and the ferrule sleeves with respect to the outputs (or other fine alignment features). Additionally, the ability of the waveguide substrate to float improves force loading on the waveguide substrate due to the connection of the input optical connector and the one or more output optical connectors.
Referring to the example waveguide module assembly 400 of
Similarly, the first shell housing 110 may include one or more resilient members 133 attached to a sidewall 513. The resilient members 133 may be spring tabs 133 as shown in
Each of the spring tabs 133, 135 are adjacent an edge of the waveguide substrate 10 when the waveguide substrate is disposed within the cavity defined by the first shell housing 110 and the second shell housing 120. In the illustrated embodiment, the spring tabs 133, 135 are adjacent to the input edge 18 of the waveguide substrate 10.
The spring tabs 133, 135 (or other resilient members) may take up any length difference between the waveguide substrate 10 exterior and the walls of the cavity defined by the first shell housing 110 and the second shell housing 120. This prevents the glass substrate from excessive “rattle” movement inside the cavity.
Referring now to
Spring tabs or other resilient members configured as biasing features may also be incorporated into the clamshell shell housing to properly bias the waveguide substrate in the vertical direction (i.e., the Z-axis direction) within the cavity, thereby accommodating variations in the thickness of the waveguide substrate.
The clamshell shell housing may also include molded covers that may be easily transitioned from an open position to a closed position to protect connector openings from dust and debris.
The output cover 760B of the example embodiment also has a U-shape in cross section with hook portions 762 that are seating in grooves 717B in both the first shell housing 710. In the illustrated embodiment, the output cover 760B has apertures 763 that allow access to the output connector openings 134 so that output optical connectors may be inserted therein.
It should be understood that other cover embodiments are also possible. For example the cover may be on a molded arm that swings to block the connector openings.
The waveguide connector assemblies described herein may also be disposed in larger enclosures depending on the application.
As shown in
The enclosure housing 880 may be configured to enclose one or multiple waveguide connector assemblies 800.
The first and/or second shell housing may include additional structures and features. Referring to
It should now be understood that embodiments of the present disclosure are directed to waveguide connector assemblies comprising a clamshell shell housing that maintains a waveguide substrate having a plurality of waveguides. The clamshell shell housing has integrated input and output connector openings for receiving input and output connectors. The clamshell shell housing also includes internal features that align the waveguides of the waveguide substrate to the input and output connector openings.
It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the disclosure. Since modifications, combinations, sub-combinations and variations of the disclosed embodiments incorporating the spirit and substance of the disclosure may occur to persons skilled in the art, the disclosure should be construed to include everything within the scope of the appended claims and their equivalents.
This application is a continuation of International Application No. PCT/US2020/040961 filed Jul. 7, 2020, which claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Application Ser. No. 62/875,550 filed on Jul. 18, 2019, the content of which is relied upon and incorporated herein by reference in its entirety.
Number | Date | Country | |
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62875550 | Jul 2019 | US |
Number | Date | Country | |
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Parent | PCT/US2020/040961 | Jul 2020 | US |
Child | 17573022 | US |