BACKGROUND

Field of the Invention

The present invention is directed to a splice element for splicing a first plurality of optical fibers and a second plurality of optical fibers.

Related Art

Communication network owners and operators are faced with increasing demands to deliver faster and better service to their customers. They can meet these needs for greater bandwidth by incorporating fiber optics in their networks. Optical fiber cables are used in the optical network to transmit signals between access nodes to transmit voice, video, and data information.

Some conventional optical fiber cables include optical fiber ribbons that includes a coated group of optical fibers that are arranged in a planar array. Optical fibers in the ribbon are generally disposed parallel to each other. Optical fiber ribbons are typically interconnected using multi-fiber optical connectors, for example, MPO/MTP connectors which can be used in data centers or other points in the network where parallel optical interconnections are needed.

Data centers rely on 10 Gb/s and 40 Gb/s transmission rates which are relatively mature technologies. The global data center Internet protocol (IP) traffic is anticipated to grow by 31 percent annually between 2016 and 2021 due to changes in the way people are using internet. See Hassen, O, "Three Trends Driving the 100G Ethernet Market", Data Center Knowledge

(Jan. 25, 2016) (http://www.datacenterknowledge.com/archives/2016/01/25/thre e-trends-driving- 1 OOg-ethernet-market/). Cloud computing, mobile devices access video and social media content around the globe are driving data centers to migrate from 10 Gb/s and 40 Gb/s transmission rates to 100 Gb/s and 400 Gb/s transmission rates.

Data centers are moving toward 40 Gb/s - 100 Gb/s transmission rates which utilize multiple parallel network links that are then aggregated to achieve higher overall data rates. Polarity in fiber optic cabling is essentially the matching of the transmit signal (Tx) to the receive equipment (Rx) at both ends of the fiber optic link by providing transmit-to-receive connections across the entire fiber optic system. Polarity is managed by use of transmit and receive pairs (duplex cabling), but becomes more complex with multi-fiber connectivity which support multiple duplex pairs such as MPO/MTP connectors. Higher bandwidth links will require more power to assure signal transmission integrity. Today, heat dissipation from the electronics is already a concern and increasing the power further will amplify the issues that data centers are already facing. This increasing need for more power as well as the desire to install future flexible structured cabling systems is driving interconnection performance to low loss performance (less than 0. ldB per connection point).

Conventional single fiber ferrule type connectors offer easy reconfiguration, but have the drawback of high optical loss (0.2 - 0.3dB) and even higher loss for multi-fiber ferruled connectors such as MPO/MTO connectors (0.35 - 0.7dB). Ferruled connectors must be cleaned every time that they are mated. In addition, space required for ferruled connectors limits the interconnection density.

Fusion splicing is another conventional interconnection method, which creates low loss permanent reliable splices. However, the handling of 250 micron fiber during preparation, fuse, and storage can be troublesome. Today, such fusion splices typically require their own splice rack in the data center.

Finally, traditional gel type mechanical splices offer permanent and reliable fiber slices with insertion loss better than connectors and approaching that of fusion splices. However, these mechanical splices employ index matching gels which are not solid materials and therefore, provide no structural integrity.

Thus, need exists for new multi-fiber interconnect technology that offer "fusion-like" optical performance to facilitate datacenter bandwidth migration from 10 Gb/s and 40 Gb/s transmission rates, today, to tomorrow's 100 Gb/s and 400 Gb/s transmission rates.

SUMMARY

According to a first embodiment of the present invention, a multifiber splice device is described that can be used to splice a plurality of first and second optical fibers. The multifiber splice device comprises a multifiber splice element having a body, having a plurality of alignment channels configured to receive the plurality of first and second optical fibers in an end-to-end manner, wherein each of the first plurality of alignment channel has an arched profile; a clamp plate, wherein at least one of the body and clamp plate being formed from a coefficient of thermal expansion silica material, and an optical coupling material is disposed in at least a portion of the plurality alignment channels such that the optical coupling material is positioned between the plurality of first and second optical fibers. The silica material used to make at least one of the body and clamp plate is a net shape cast and cure silica material. In another aspect of the first embodiment, the clamping plate of the multifiber splice device is a thin flexible glass clamping plate that is flexed to further align and secure terminal ends of the plurality of first and second optical fibers in an interconnection region of the multifiber splice element. The multifiber splice device further includes a means of imparting a pressing force on the clamp plate which causes the clamping plate to flex aligning and securing terminal ends of the plurality of first and second optical fibers in the alignment channels in an interconnection region of the multifiber splice element.

According to a second embodiment of the present invention, a multifiber splice device is described that can be used to splice a plurality of first and second optical fibers. The multifiber splice device comprises a multifiber splice element having a body, having a plurality of alignment channels configured to receive the plurality of first and second optical fibers in an end-to-end manner; a clamp plate, wherein the clamping plate is a thin flexible glass clamping plate that is flexed to align and secure terminal ends of the plurality of first and second optical fibers in an interconnection region of the multifiber splice element; wherein at least one of the body and clamp plate being formed from a coefficient of thermal expansion silica material, and an optical coupling material is disposed in at least a portion of the plurality alignment channels such that the optical coupling material is positioned between the plurality of first and second optical fibers. The silica material used to make at least one of the body and clamp plate is a net shape cast and cure silica material.

In one aspect of the embodiments, the optical coupling material is at least one of an index matching material or an optical adhesive, and when the optical coupling material is an optical adhesive, the optical adhesive is curable via actinic radiation to make a permanent multifiber optical splice. In particular, the optical adhesive is a blue light curable adhesive. The exemplary optical adhesive comprises an adhesive composition containing non-aggregated, surface- modified silica nano-particles dispersed in an epoxy resin.

In another aspect of the embodiments, the alignment channel of the multifiber splice device has an arched profile that includes a generally planar portion at entrance openings at either end of the alignment channel, the alignment channel gently rises between the entrance openings and an interconnection region centrally located on the body and where the alignment channel crests in a shallow dome within the interconnection region.

According to a third embodiment of the present invention, an optical cassette is described that comprises an enclosure having a top, a bottom and a plurality of side walls disposed between the top and the bottom, and an element housing disposed through one of the plurality of sidewalls. A multifiber splice element is disposed in the element housing to interconnect terminal ends of a plurality of outside optical fibers to a plurality terminal ends of fibers disposed within the enclosure, wherein the multifiber splice element has a body, having a plurality of alignment channels configured to receive the plurality of first and second optical fibers in an end-to-end manner; a clamp plate, wherein at least one of the body and clamp plate being formed from a coefficient of thermal expansion matched silica material; and an optical coupling material disposed in at least a portion of the plurality alignment channels such that the optical coupling material is positioned between the plurality of first and second optical fibers.

A plurality of signal paths exit the cassette through one of the plurality of sidewalls. In some embodiments, the plurality of signal paths comprise a connection point at the sidewall where the plurality of signal paths exit the cassette. The connection point can be an optical fiber connector connection point or an optical fiber splice connection point. The connection point(s) can be configured as either single fiber connection points or multifiber connection points. In an exemplary use in which the cassette comprises single fiber connection points, the plurality of single fiber connector connection points are paired, such that the first of the pair of single fiber connection points is designated as a transmit port and the second of the pair of single fiber connection points is designated as a receive port. In this aspect, signals carried by the plurality of outside optical fibers can be reordered within the cassette such that the signals leave the cassette in a different order than the enter the cassette.

According to a fourth embodiment of the present invention, a method of splicing a plurality of first optical fibers to a plurality of second optical fibers is described. The method comprises inserting the plurality of first fibers into a plurality of alignment channels formed in a multifiber silica splice element, wherein the plurality of alignment channels are configured to receive the plurality of first and the second optical fibers in an end-to-end manner, inserting the plurality of second fibers into the plurality of alignment channels such that terminal ends of the plurality first fibers are brought in close proximity to ends of the plurality of second fibers; and curing an optical adhesive disposed in the plurality of alignment channels by directing an effective amount of actinic radiation towards the optical adhesive. In some aspects, the curing step comprises directing an effective amount of blue light through at least one of the plates towards the optical adhesive.

According to a fifth embodiment of the present invention, a plug and splice interconnect system is described that comprises a multi-fiber splice device comprising an element housing and a multifiber splice element disposed in the element housing to interconnect terminal ends of optical fibers of a pair of fiber ribbons, wherein the multifiber splice element has a body, having a plurality of alignment channels configured to receive terminal ends of the optical fibers in an end-to-end manner; a clamp plate, wherein at least one of the body and the clamp plate is formed from a low coefficient of thermal expansion silica material; and a multifiber bare-fiber holder that houses prepared ends of optical fibers from one of the pair of ribbons, wherein the prepared ends are introduced into the alignment channels of multifiber splice element when the multifiber bare-fiber holder is connected to multi-fiber splice device.

The exemplary interconnection system can include a clamping plate that is a thin flexible glass clamping plate that is flexed to align and secure terminal ends of optical fibers in an interconnection region of the multifiber splice element.

The multifiber bare-fiber holder of the interconnection system comprises a ribbon anchor, a fiber alignment mechanism to align and protect the prepared ends of the plurality of optical fibers from one of the pair of fiber ribbons and a locking mechanism to secure the multifiber bare-fiber holder to the multi-fiber splice device. In some aspects, the fiber alignment mechanism is a fiber alignment collar that is slideably mounted in the multifiber bare-fiber holder, and in other aspects the locking mechanism is a locking sleeve configured to connect to the element housing of the multifiber splice device.

The exemplary interconnection system can further comprise an optical coupling material disposed in at least a portion of the plurality alignment channels such that the optical coupling material is positioned between the terminal ends of the optical fibers.

In some embodiments, the exemplary interconnection system is used to form an optical fiber harness assembly when the multifiber splice device and the multifiber bare-fiber are connected.

In other embodiments, the exemplary interconnection system is disposed at least partially in a sidewall of a housing to form a fanout cassette.

"Actinic radiation" is radiation capable of initiating a photoreaction process. Actinic radiation can be produced by any light source that provides sufficient intensity at a wavelength appropriate for the photoinitiator or photosensitizer used in the photoreactive composition.

The above summary of the present invention is not intended to describe each illustrated embodiment or every implementation of the present invention. The figures and the detailed description that follows more particularly exemplify these embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be further described with reference to the accompanying drawings, wherein: Figs. 1 A-1C are three views of a splice element according to a first embodiment of the invention.

Figs. 2A-2C are three views of a splicing process utilizing the splice element of Figs. 1 A and IB.

Figs. 3 A and 3B are two cross sectional views of the splice elements shown in Figs. 2B and 2C, respectively.

Fig. 4 shows one application for a multifiber a plug and splice interconnect of the present invention.

Figs. 5A and 5B are two exploded views showing a multi-fiber splice device and a multifiber bare-fiber holder of the multifiber a plug and splice interconnect shown in Fig. 4.

Figs. 6A-6C illustrate splicing of an optical fiber ribbon in the plug and splice

interconnect system of Figs 5A-5D.

While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the appended claims.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In the following Detailed Description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as "top," "bottom," "front," "back," "leading," "forward," "trailing," etc., is used with reference to the orientation of the Figure(s) being described. Because components of embodiments of the present invention can be positioned in a number of different orientations, the directional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention.

Telecommunications standards, such as the TIA 568.3-D Optical Fiber Cabling

Components standard, have defined three basic methods for handling polarity by managing various polarity components within the network links to assure that transmit-to-receive pairings are met. The three basic methods use multi-fiber cable assemblies with MPO/MTO connectors in various configurations of "key up to key up" links and "key up to key down" links with straight through fiber ribbons or "pair wise flipped" fibers in the ribbons. In one embodiment of the invention, traditional multifiber optical connectors that are rarely or never disconnected can be replaced by a more permanent connectivity, such as a multifiber optical fiber splice technology as described herein.

In a first embodiment, the optical fiber splice comprises an alignment mechanism and an optical coupling material. The alignment mechanism can be formed using a sol casting resin to generate net shape silica ceramic parts. In one aspect, the optical coupling material can be an optical adhesive that can be used to permanently secure the plurality of parallel optical fibers in the exemplary splice element. An exemplary optical adhesive can be cured with actinic radiation via a rapid and straightforward procedure using a visible, e.g., blue, LED light source. In an alternative aspect, the optical coupling material can be an index matching material configured to optimize he signal transmission thought the optical fiber splice, the exemplary splice element provides for an optical fiber splice with very low optical loss to achieve near-fusion splice levels of optical loss and reflectivity performance, thus providing a reliable, low loss, permanent termination which may be accomplished by a minimally trained craft person.

In a first embodiment, Figs. 1 A-1C show a bare fiber holding plate or splice element 100 configured to join a plurality of parallel optical fibers 54, 54' of first and second optical fiber ribbons 50 as shown in Fig 2C. The body can have the shape of a generally rectangular solid, semi-cylindrical solid or other shape having at least one generally flat major surface. The splice element 100 comprises a splice body 101 having a first end 101a and a second end 101b. Splice body 101 has an integral alignment mechanism comprising a plurality of alignment grooves or channels 112 that extend from the first end to the second end of the splice body. Each alignment channel is configured to guide and support a single optical fiber. In the exemplary embodiment shown in Fig. 1 A, the splice element has 12 parallel alignment channels to splice together 2-12 fiber optical ribbons in an end-to-end configuration. In alternative embodiments, the exemplary optical fiber slice element can have fewer or more alignment channels depending on the final application and the number of optical fibers to be spliced. Thus, in some embodiments, the splice element can have two parallel alignment channels for joining a pair of duplex optical fiber cables.

In one embodiment, alignment mechanism is configured to align a plurality of optical fibers, which are then bonded or spliced together end-to-end using an optical adhesive, or a mechanical clamping device with or without an index matching gel. In some embodiments, the alignment channels 112 can be substantially flat or planar as they extend from the first and second ends to the interconnection region 105, which can be centrally disposed on splice element

100. In another aspect, the alignment channels can have a generally arched profile to aid insertion of the optical fibers into the alignment channels in the proper position. For example, alignment channel 112 can include a generally planar portion 112a at the entrance openings or apertures 113a and 113b which gently rises in rising portion 112b between the entrance openings and the interconnection portion 105 where the alignment channel crests in a shallow dome 112c within the interconnection region as shown in Fig. 3 A.

In an alternative embodiment, the alignment channels can be substantially flat as they extend from the first end of the splice element to the second end of said element.

Alignment channels 112 can be continuous or can be discontinuous. In the exemplary embodiment shown in Fig. 1 A, the alignment channels are continuous structures extending from the first entrance opening 113a at the first end 101a of splice body 101 to the second entrance opening 113b at the second end 101a of splice body 101.

The fibers can be inserted into the alignment mechanism through entrance openings or apertures 113a and 113b. In some aspects, the entrance apertures 113a, 113b can comprise a funneling inlet portion formed by the tapering of the partitions 114 between adjacent channels to provide for more straightforward fiber insertion. In other embodiments, the entrance apertures can be fully or partially cone or funnel-shaped to guide the insertion of the optical fibers into the alignment channels 112.

The entrance openings 113a, 113b are characterized by a channel pitch (i.e. the distance between the centerline of adjacent alignment channels). In the embodiment, shown in Figs. 1 A and IB, the channel pitch at the first end of the splice element is the same as the channel pitch at the second end of the splice element. In this exemplary embodiment, the channel pitch is approximately the same as the inter-fiber spacing in a conventional 12 fiber ribbon. In an alternative embodiment, the channel pitch at the first end of the splice element and the channel pitch at the second end of the splice element can be different. For example, the channel pitch at the first end of the splice element can be set to the fiber spacing of a conventional optical fiber ribbon, while the channel pitch at the second end of the splice element can be at a different value such as when splicing individual optical fibers or when splicing two or more smaller optical fiber ribbon ribbons or optical fiber modules to a larger ribbon fiber.

In the exemplary embodiment of Figs. 1 A and IB, the entrance openings 113a, 113b are disposed in a common plane and all of the fibers being joined by the exemplary splice element enter the guide channels along this common plane. Alternatively, some of the entrance openings can be disposed on a different plane that is vertically offset from the entrance openings. This can be useful when the inter-fiber spacing on one side of the splice element is different than the inter-fiber spacing on the second side of the splice element. In another aspect, splice element 100 can include a fiber comb portion 115 disposed adjacent to the entrance openings or apertures 113a and 113b on each side of body 101. The fiber comb can be used to support, align and guide the optical fibers being terminated in the exemplary splice element 100. The alignment channels 112 pass through the comb portion. The partitions between the adjacent alignment channels in the comb portion can be taller than along other portions of the alignment channels. The taller partition portions 114a (Figs. 1 A and 3 A) allow the individual fibers to be out of position by up to a half fiber diameter while still feeding into the correct alignment channels providing a self-centering mechanism for the optical fibers in the alignment channels.

Splice element 100 can also include a clamp plate 120 (shown in Figs. IB and 1C), wherein the clamp plate can be a flat transparent plate disposed over at least the interconnection region 105 of the splice element. Positions posts 119 extend from the upper surface of body 101 adjacent to the interconnection region to assure and maintain the proper positioning of clamping plate 120 over the interconnection region.

Alignment channels 112 can be formed in either body 101 or clamp plate 120, or alignment channels can be formed in both body 101 and clamp plate 120. The alignment channels 112 can have a semi-circular cross section, a trapezoidal cross section, a rectangular cross section or a v-shaped cross section. In the embodiment of Figs. 1 A and IB, alignment groove 112 is formed in body 101, while clamp plate 120 has a flat-shaped major surface. The body and the clamp plate are brought together to hold one or more fibers in place in the alignment groove prior to curing of the optical adhesive or mechanical clamping of the splice element. An optical adhesive usable with the exemplary optical splice elements described herein, is described for example in US Patent Publication No. 2018/0072924, which is incorporated herein in its entirety. For example, the optical adhesive can be an epoxy-based adhesive composition containing non-aggregated, surface-modified silica nano-particles dispersed in an epoxy resin that is cured by exposure to blue light.

Exemplary light sources for curing the adhesive compositions described herein can have an output density from about 500 mW/cm ² to about 3000 mW/cm ² and may include a

conventional blue light source such as a Paradigm™ DeepCure LED curing light available from 3M Company (St. Paul, MN) or can be LED curing array. In an exemplary aspect, the LED light source provides not only the photonic initiation of the polymerization reaction, but can also have sufficient energy to photonically heat the bonding area, enabling the adhesive to achieve a higher glass transition temperature (Tg) than can be generated by the photonic initiation alone. The higher Tg of the adhesive can create more stable optical splices when used to bond optical fibers in an optical splice device, allowing the resulting splice connections to pass more rigorous environmental stress tests.

In an exemplary aspect, the LED array will have a wavelength that is optimized for material curing and modification. Various form factors and features may include an LED array curing device designed to be a portable, hand held unit, for example, an LED light pen, an LED array, etc. to cover a targeted area (e.g. radial, segmented, and organic shapes). Selective control of particular LEDs in the array permits smaller material regions to be exposed. The thermal flux can be managed by a large surface area heat sink and/or forced air flow through the array.

Current approaches to optical curing often involve targeting a reactive material with large external lamps. Uniform radiometric emission levels may need to be on the order of 100 mW/cm ² or much higher. When using LED-based light sources, the spectral width of the LEDs, placement and layouts are carefully defined to provide a uniform light distribution for curing at the desired wavelengths and intensities.

In an exemplary aspect, the LEDs can be arranged in a one-dimensional array, while in other aspects, the LEDs can be arranged in a two-dimensional array. In an exemplary aspect, the LEDs can be arranged in a plurality of banks or strips that are then configured into a two- dimensional array to allow selective exposure over a given cure region. LEDs can be arranged in a regular array with uniform spacing, for example with linear, hexagonal or other geometric placement to maximize light uniformity, minimize number of LEDs used, or for other reasons. In an exemplary aspect, an array of LEDs may be configured to be evenly distributed over the area intended to be cured, plus a reasonable perimeter, from a small fraction of the total area, to several times the total area, to insure uniform curing of a sample from center to edges.

In one aspect, the exemplary adhesive can be cured using an LED array curing source after about a 60 second exposure, preferably after about a 30 second exposure.

Clamping plate 120 can be a thin flexible glass clamping plate. The clamping plate can be placed in a first or unflexed position to allows space for insertion of the optical fibers and in a second flexed or clamped position upon application of an external force that the flexible glass clamping plate to close any clearance or free space as well as to align and secure the fibers in the interconnection region. In an exemplary embodiment, an optical adhesive can be irradiated to cure the adhesive permanently fixing the optical fibers in the splice element 100. In one aspect, the force exerted on the clamping plate is permanent, while in other aspects the force can be released after the adhesive is cured. Figs. 2A-2C illustrate making a splice connection with splice element 100, which will be explained in detail below. In an exemplary aspect, the clamping plate can be rectangular, square, circular or other polygonal shape as needed for a given splice device.

In an alternative aspect, the clamping plate can be a non-silica based flexible clamping plate. For example, the non-silica based flexible clamping plate can be formed of a thin piece of metal such as Invar or stainless steel or a low CTE polymers including a glass filled liquid crystal polymer material such as VECTRA® A130 LCP Glass Reinforced available from Ticona Engineering Polymers (Florence, KY). In an exemplary embodiment, the clamping plate can have a thickness between about 25 microns to about 250 microns, preferably between about 75 microns and about 125 microns.

At least one of the slice element body 101 and clamp plate 120 is formed from a silica material, especially a net shape, cast and cure silica materials, is described for example in International Publication No. WO 2018/044565 and US Publication No. 2018/0067262, each of which is incorporated herein in its entirety. In an alternative embodiment, both the splice element body 101 and a clamp plate 120 are formed from a net shape cast and cure silica material. In an exemplary embodiment, parts made from net shape cast and cure silica material are transparent. For example, net shape cast and cure silica material can have a transparency of greater than about 90% at a wavelength of light between 430 nm to about 480 nm. Such a transparent net shape cast and cure silica material allows for the use of a visible light source to be directed through one of the splice element body or the clamping plate from the outside of the structure to cure the optical adhesive disposed therein. By utilizing a net shape cast and cure silica alignment mechanism and an adhesive composition containing silica nano-particles, the temperature performance of the splice element can be stable across a wide temperature range, as the thermal properties of the optical fibers and splice element are essentially the same.

In some embodiments, the surfaces of silica splice element 100 and/or clamp plate 120 may be coated with an aluminum, copper, or Parylene coating (having a thickness of, e.g., between 3 μπι and 25 μπι). While not required, such conformable materials may be useful to optimize the fiber retention, fiber stress, and concentric alignment. For example, Parylene is transparent, can be easily applied by evaporation, and is stable in high temperatures. For example, Parylene C, available from Specialty Coating Systems (Indianapolis, IN), is conventionally used to coat printed circuit boards and human implants.

In one exemplary aspect, the exemplary multifiber splice device can be used to join two separate multifiber cables as described previous, while in an alternative embodiment the exemplary multifiber splice device can be used to repair a damaged multifiber cable, by simply cutting out the damaged portion of the cable and splicing the two cable portions as if they were two discrete multifiber cables.

The exemplary splice element can be disposed in a structure or housing to protect the splice and/or provide eye safety or facilitate handling when in use as will be described below in reference to Figs. 4 and 5A-5C. In addition, the housing can include features to facilitate fiber alignment, splice actuation and in some embodiment a means to allow for initiation and cure of the optical coupling material.

An exemplary splicing process is shown in Figs. 2A-2C, where a first fiber ribbon 50 comprising a plurality of first optical fibers 54 can be spliced to a second fiber ribbon (not shown) comprising a plurality of second optical fibers 54'. Optical fibers are oriented in a parallel planar array in the fiber ribbon and are surrounded by a ribbon jacket 52. The optical fibers in the exemplary ribbons can be standard single mode or multimode optical fibers, such as

SMF 28, OM2, OM3, OM4, OM5 fiber ribbon cables (available from Corning Inc.).

First a section of the ribbon jacket 52 is removed from the terminal end of ribbon fiber 50 to expose optical fibers 54. The protective acrylate coating on the optical fibers can be stripped to the desired length. In one aspect, acrylate coating on the optical fibers can be stripped and cleaved to a length of between 2 mm and 15 mm, preferably about 5 mm. In one exemplary embodiment, the fibers can be cleaved so that the end face of the optical fiber is perpendicular to the longitudinal axis of the optical fiber (i.e. cleaved flat). In an alternative embodiment, the fibers can be cleaved at an angle that deviates from perpendicular by 2° to about 10°, preferably between 4° to about 8°. In some embodiments, a post-cleave end finishing step may be employed to shape or bevel the ends of the optical fibers. Exemplary post-cleave end finishing processes can include abrasive polishing and/or laser finishing.

The ends of optical fibers 54 of the first fiber ribbon 50 are inserted into entrance openings 113a at the first end 101a of the splice element 100 as indicated by directional arrow 99 shown in Fig 2A. The fibers are slid through alignment channels 112 until the ends of the optical fibers are disposed in the center of interconnection region 105.

The second fiber ribbon is then prepared as described above. The second optical fibers

54' (Fig. 2B) of the second ribbon 50 are inserted into entrance openings 113b at the second end 101b of the splice element 100 and slid through the corresponding alignment channels until the ends of the optical fibers are disposed in the center of interconnection region 105 and abut against the ends of first optical fibers 54, as shown in Fig. 2B and 3 A. Next as shown in Figs.

2C and 3B a force, F, is applied to clamp plate 120 causing a portion of the clamp plate to flex toward splice element 100 to close any clearance or free space between the clamp plate and the fibers as well as to align the fibers in the interconnection region. The fiber ends are contacted in the interconnection region where the fiber ends can be generally concentrically gripped when the splice element and clamp plate are pressed together.

In an exemplary aspect, splice element 100 can be preloaded with an optical adhesive (not shown) in the interconnection region. After applying the force to the clamp plate, the optical adhesive can be irradiated with an appropriate wavelength of light to cure the adhesive permanently fixing the optical fibers in the splice element 100. Once actuated, a light source (not shown), such as a conventional blue light source, can be utilized to provide the necessary actinic radiation through the transparent clamp plate 120 (or transparent body 101) to cause the optical adhesive to cure.

In another embodiment, an exemplary field termination process is provided. During transportation, the splice element and pre-loaded adhesive can be protected from dirt and light exposure using known peel tape tabs on the splice element and/or black or optically opaque to visible light blister packaging. Field fibers can be cleaved using an instrument such as the 3M™ Easy Cleaver, or another commercial cleaver such as CI-01 provided by Ilsintech (Korea).

Field fibers can be inserted into the entrance openings 113a, 113b of the splice element 100. The clamp plate 120 can be displaced axially, such as described above. A Paradigm light pen (available from 3M Company, Item # 76962), battery operated LED array, a corded light source, etc. that emit blue light in the range of 430 nm to 480 nm. can be used to cure the adhesive. An installation tool with a nest (not shown) can be provided to align and hold the light source over the splice window region, during the approximate 20-30 second splice adhesive cure cycle. This type of docking operation can remove craft variability, ensuring intended light exposure to reach the adhesive.

The exemplary multifiber devices can be used in a wide range of applications where low loss optical connections are needed, especially when the connections are semi-permanent or permanent. In some embodiments, the exemplary multifiber devices can be used in fiber optic cassettes, terminals, patch panels, etc. where the splice can be located at a bulkhead or through the wall of an enclosure. For example, an optical cassette or terminal can comprise an enclosure having a top, a bottom and a plurality of side walls disposed between the top and the bottom, and an element housing disposed through one of the plurality of sidewalls. A multifiber splice element can be disposed in the element housing to interconnect terminal ends of a plurality of outside optical fibers to a plurality terminal ends of fibers disposed within the enclosure. In one aspect, the multifiber splice element can be a multifiber splice element that is similar to splice element 100 described above, where the multifiber splice element has a body, having a plurality of alignment channels configured to receive the plurality of first and second optical fibers in an end-to-end manner; a clamp plate, wherein at least one of the body and clamp plate being formed from a coefficient of thermal expansion matched silica material; and an optical coupling material disposed in at least a portion of the plurality alignment channels such that the optical coupling material is positioned between the plurality of first and second optical fibers.

A plurality of signal paths exit the cassette or through one of the plurality of sidewalls. In some embodiments, the plurality of signal paths comprises a connection point at the sidewall where the plurality of signal paths exit the cassette. The connection point can be an optical fiber connector connection point or an optical fiber splice connection point. The connection point(s) can be configured as either single fiber connection points or multifiber connection points. In an exemplary use, the cassette or terminal can comprise single fiber connection points where the plurality of single fiber connector connection points are paired, such that the first of the pair of single fiber connection points is designated as a transmit port and the second of the pair of single fiber connection points is designated as a receive port. In this aspect, signals carried by the plurality of outside optical fibers can be reordered within the cassette or terminal such that the signals leaving the cassette are in a different order than they enter the cassette. In some embodiments, this reordering of the signal paths is used to manage the polarity of the rend and receive ports.

Fig. 4 shows one exemplary optical fan-out cassette 200 having a plurality of single fiber connections 220 on one side of the cassette and a plug and splice interconnect system 250 on the other side the cassette. In this embodiment, the plug and splice interconnect is a two-piece connection system comprising a plug and receptacle arrangement.

Optical cassette 200 is an enclosure or housing 201 having a top (not shown) and a bottom 202 and a plurality of side walls 203, 204 disposed between the top and the bottom. The enclosure has an interior cavity within the side walls for receiving and supporting fan-out optical fibers. A plurality of single fiber connections can be made through ports on the front side wall

204. In particular, the ports can be a plurality of single fiber connector adapters 222 that are mounted in front side wall 204. Single fiber connector adapters 222 can be any standard format connector adapter such as LC-format connector adapters, SC-format connector adapters, etc. The connector adapters shown in Fig. 4 are duplex LC connector adapters.

Side wall 203 can be a single continuous side wall that extend from one end of front side wall 204 around the circumference of the enclosure to the second end of the front side wall. In an exemplary aspect side wall 203 can comprise a plurality of wall segments 203a-203e. A multifiber plug and splice interconnect 250 can be disposed in side wall 203. In the embodiment shown in Fig. 4, the plug and splice interconnect 250 is disposed in wall segment 203c. The multifiber plug and splice interconnect 250 comprises a multi-fiber splice device 260 (i.e. the receptacle portion of the two-piece connection system) mounted in the optical fan-out cassette 200 and a multifiber bare-fiber holder 280 (i.e. the plug portion of the two-piece connection system) which can be secured in the multi-fiber splice device in the field. In an exemplary aspect, the multi-fiber splice device can be factory assembled onto the end of multifiber stub 212 and mounted into side wall 203 of optical fan-out cassette 200. In an exemplary aspect, the multifiber stub can be an array of individual optical fibers, a fiber ribbon or a collection of individual fibers that have been ribbonized to gather the individual fibers into a single, readily handleable configuration. In an alternative embodiment, a multifiber plug and splice

interconnect 250 can be disposed in the front side wall of the cassette (such as sidewall 204).

Fan-out optical fibers 210 can be arranged in a generally planar array or a two- dimensional array such as a radial array or a hexagonal array. Each of the individual fan-out optical fibers is terminated with an optical fiber connector 225 at one end which are plugged into the single fiber connector adapters 222 disposed in the front wall 204 of cassette 200 and is joined into a multifiber stub 212 at their other end. In some applications, such as those encountered in fiber to the home (FTTH) applications, the optical fiber connector on a given fan- out optical fiber 210 can be routed to the port in the cassette that corresponds to the position that the fan-out optical fiber occupies in the multifiber stub, such that the first fanout fiber 210a that occupies the first position in the multifiber stub is routed to the first port 222a in the optical cassette 200.

In other applications, the ports in the optical cassette are matched in a duplex pair. For example, in high speed data systems used in wireless and datacenter applications, ports 222a and 222b can form a duplex pair. The send and receive fibers for a given duplex pair may not be disposed adjacent to each other in the incoming ribbon fiber cable 50. In this case, the exemplary optical cassette can be configured such that the fanout fiber 210a, which is in the first position in the multifiber stub, corresponds to the transmit optical fiber in the first duplex pair in ribbon fiber cable 50 and can be routed to port 222a of optical cassette 200, and fanout fiber 210b, which is in the twelfth position in the multifiber stub, corresponds to the receive optical fiber in the first duplex pair in ribbon fiber cable 50 and can be routed to port 222b of the optical cassette.

One of ordinary skill in the art would recognize that the fanout fibers 210 could adopt other alternative routings within the cassette. In addition, while the cassette shown in Fig. 4 is exemplified as having twelve fanout fibers in the multifiber stub, multifiber stubs with other fiber counts (e.g. 8 fanout fibers, 16 fanout fibers, 24 fanout fibers, etc.) are considered within the scope of the present disclosure. Additionally, the exemplary cassette may include more than one plug and splice interconnect 250.

A plurality of cassettes can be gathered together and mounted in a rack system in a datacenter or central office. In an alternative embodiment, the cassette can be a sealed enclosure or terminal to provide added environmental protection.

In a first aspect, cassettes or terminals according to the present invention can include a plurality terminal ends of fibers disposed within the enclosure factory installed into the multifiber splice element. In a second aspect, the plurality terminal ends of fibers disposed within the enclosure can be field installed into the multifiber splice element of the cassette or terminal. In a third aspect, all optical connections disposed within the exemplary cassette or terminal made in the factory and assembled into the cassette or terminal allowing the terminal to be factory sealed such that an interior of the cassette is inaccessible thereafter.

Multifiber plug and splice interconnect 250 is configured to allow the field

interconnection of optical fan-out cassette 200 in applications where repeated reconfiguration is not needed. The exemplary technology described herein provides optical splice connection performance with the handleabilty of an optical fiber connector. In some embodiments, the exemplary multifiber a plug and splice interconnect system can eliminate the need for the field preparation of bare optical fibers, including conventional multifiber stripping, cleaving, cleaning and polishing operations typically required for field termination of optical fiber cables.

The multi-fiber splice device 260 of the multifiber a plug and splice interconnect 250 include an exemplary splice element 265 that is disposed within element housing 270. The splice element 265 is generally similar to splice element 100, except that the body 266 of splice element 265 has a semi cylindrical shape compared to the substantially cuboid platelet shape of splice element 100. Splice element 265 includes an integral alignment mechanism comprising a plurality of alignment grooves or channels 267 that extend from the first end 266a to the second end 266b of splice body 266, wherein each alignment channel is configured to guide and support a single optical fiber.

Element housing 270 has a generally tubular shape that includes a central passageway 271 extending from a first end 270a to a second end of the element housing that is configured to hold and protect splice element 266 within the passageway. The element housing can include a flange 274 disposed mid-way along the element housing to aid in positioning the multi-fiber splice device 260 in the sidewall 203 of optical fan-out cassette 200. The flange abuts against one side of sidewall 203 and a holding mechanism can be positioned on the other side of the sidewall to secure the multi-fiber splice device in the cassette. The element housing can include a mounting area between the flange and the second end of the element housing that can be configured to accommodate the holding mechanism in the form of an actuation cam. In one embodiment, the holding mechanism can be a spring clip (not shown) that can be locked into a groove (not shown) formed in the surface of the mounting area adjacent to the side wall. In an alternative embodiment, the holding mechanism can be a threaded or mechanical fastener (not shown) that can be secured onto a mounting area that has a threaded surface. In another alternative embodiment, the element housing can be permanently bonded in the sidewall by a structural adhesive or by a conventional welding technique. In yet another embodiment, the element can be integrally formed with the sidewall of the cassette.

In the exemplary embodiment shown in Fig. 5 A, a strain relief boot 269 can be fitted over the mounting area. The mounting area can have at least one annular barb 273 or annular rows of teeth to that is configured to secure the strain relief boot to the element housing. In this embodiment, the strain relief boot can serve as the holding mechanism that secures the multi- fiber splice device 260 in the side wall of the cassette.

The multifiber bare-fiber holder 280, as shown in Fig. 5B, of the multifiber plug and splice interconnect 250 hold and protect each of plurality of prepared ends of optical fibers that are configured for splicing via multi-fiber splice device 260. A plurality optical fibers 54 from fiber ribbon 50 are held by multifiber bare-fiber holder 280 (e.g., at a predetermined protrusion distance). The exemplary multifiber bare-fiber holder comprises a ribbon anchor, a fiber alignment mechanism to align and protect the prepared fiber ends and a locking mechanism to secure the multifiber bare-fiber holder to the multi-fiber splice device. In the exemplary embodiment shown in Figs. 5B and 6A-6C, the fiber alignment mechanism can be a fiber alignment collar 295 and the locking mechanism can be a locking sleeve.

The ribbon anchor 282 having a first end 282a and a second end 282b, a locking sleeve

290 disposed on the first end of the ribbon anchor and a spring-loaded fiber alignment collar 295 disposed within the first end of the ribbon anchor. A strain relief boot 289 can be disposed at the second end 282b of the ribbon anchor to provide strain relief and bend control for fiber ribbon 50 entering the ribbon anchor. Ribbon anchor 282 can have a generally hollow cylindrical structure formed from two half shells 283a, 283b when they are latched together by latch arms 287 fitted into latch receptacles 288, although other generally tubular structures are possible. The half shells include spaced apart internal positioning walls 284a, 284b within their interior that are configured to position a fiber ribbon 50 along the centerline of the ribbon anchor. Each of the positioning walls includes a slot 285 formed in the top surface thereof. The slot has dimensions such that when the half shells are mated together that the combined slot has interior dimensions that are only slightly larger than the ribbon fiber which will be mounted in the multifiber bare- fiber holder 280. The space between the positioning walls can be filled with a potting compound or an adhesive to secure the fiber ribbon within the ribbon anchor.

Fiber alignment collar 295 can be disposed within the first end of the ribbon anchor so that it is free to slide longitudinally with respect to the ribbon anchor from a first or extended position, shown in Fig. 6 A to a second or retracted position, shown in Fig. 6C. In a first aspect, the alignment collar can be generally cylindrical, as shown in Fig. 5B. The alignment collar can have a plurality of parallel bores 296 extending therethrough. The bores are sized to be marginally larger than and at the same pitch as the optical fibers 54 that will pass therethrough, so that the fibers are free to move longitudinally within the bores. A compression spring 298 is disposed in the first end of the ribbon anchor between positioning walls 284a and the fiber alignment collar.

Locking sleeve 290 is a substantially cylindrical tubular member that can be rotatably connected to the ribbon anchor. In an exemplary aspect, the locking sleeve can include slots extending through the locking sleeve. The slots engage with rotation control catches 286 near the first end of the ribbon anchor. The width of the catches is smaller than the width of the slot allowing the locking sleeve to rotate by a controlled amount. In an exemplary aspect, the locking sleeve can rotate by about 15 degrees to about 120 degrees, preferably about 30 degrees to about 90 degrees around the centerline of the ribbon anchor. The locking sleeve can secure multifiber bare-fiber holder 280 to the multi-fiber splice device 260 via a bayonet connection mechanism utilizing for example connection pegs 276 (Fig. 5A) on the multi-fiber splice device and the bayonet connection slots 292 on the locking sleeve. In an alternative, locking sleeve can secure multifiber bare-fiber holder 280 to the multi-fiber splice device 260 via a conventional threaded connection mechanism. In yet another alternative, the locking sleeve can secure multifiber bare-fiber holder 280 to the multi-fiber splice device 260 via an interference connection mechanism.

Figs. 6A-6C are a series of cross sectional detail views showing the interconnection of multifiber bare-fiber holder 280 with multi-fiber splice device 260 disposed in a sidewall 203 of cassette 200 to form multifiber plug and splice interconnect 250. Fig. 6A shows the multifiber bare-fiber holder and the multi-fiber splice device in a fully disconnected state with the fiber alignment collar 295 disposed in its forward position in the locking sleeve 290 protecting the ends of the cleave bare fiber ends (not shown). The multifiber bare-fiber holder is moved toward cassette 200 as indicated by directional arrow 299a until the front face of the fiber alignment collar 295 abuts against the second end of element housing 270 as shown in Fig. 6B. As the multifiber bare-fiber holder continues to move toward cassette 200 as indicated by directional arrow 299a, the fibers emerge through the bores in the alignment collar entering the alignment channels of splice element 265. After the fibers are fully inserted into the alignment channels, the bare fiber holder may be locked in place by turning the locking sleeve to engage the bayonet connection mechanism. Fig. 6C shows multifiber bare-fiber holder 280 fully engaged with multi-fiber splice device 260, such that the fiber alignment sleeve 295 is disposed adjacent to the end of the ribbon anchor 282.

In an alternative embodiment, multifiber plug and splice interconnect 250 can be used without a cassette housing 201 to make an optical fiber harness assembly. For example, multifiber plug and splice interconnect 250 may be used to directly connect fanout portion to a continuous transmission portion comprising a fiber ribbon 50 using the multi-fiber splice device 260 and a multifiber bare-fiber holder 280 which can be secured in the multi-fiber splice device in the field or in the factory. This can be especially advantageous when the fanout portion is made in a first location, the transmission portion is made at a second location and where the fanout portion to a continuous transmission portion are brought together at a third location.

In some exemplary embodiments where a permanent final connection is desired, the optical fibers held by the bare fiber holder 260 can be secured in splice element 265 by an adhesive. The adhesive can be a two-part epoxy adhesive, an anaerobic adhesive or a light curable adhesive. When the adhesive used is a light cured adhesive, the element housing should be made of a material that is transparent to the wavelength of light used to cure the adhesive. In some aspects, the splice element may also be transparent to the wavelength of light used to cure the adhesive.

The exemplary multifiber splice devices and multifiber splice connection systems described herein provide fusion-like performance without the need for fusion splicing, so no expensive or delicate optical fusion machine is required. Such fusion machines require a source of electrical power, time to heat to shrink the protective sleeve, and are precision instruments which are easily damaged if dropped.

An exemplary connection made in accordance with the present disclosure should have an insertion loss of less than 0.1 dB. a return loss variation of less than 10 dB when temperature cycled from -40°C to 75°C and have a pullout strength of greater than 0.5 lbf per fiber. List of embodiments

Embodiment 1 A is a multifiber splice device for splicing a plurality of first and second optical fibers. The multifiber splice device comprises a multifiber splice element having a body, having a plurality of alignment channels configured to receive the plurality of first and second optical fibers in an end-to-end manner, wherein each of the first plurality of alignment channel has an arched profile; a clamp plate, wherein at least one of the body and clamp plate being formed from a low coefficient of thermal expansion silica material, and an optical coupling material is disposed in at least a portion of the plurality alignment channels such that the optical coupling material is positioned between the plurality of first and second optical fibers.

Embodiment 2A is the multifiber splice device of embodiment 1 A, wherein the optical coupling material is at least one of an index matching material or an optical adhesive.

Embodiment 3 A is the multifiber splice device of embodiment 2A, wherein the optical adhesive is curable via actinic radiation to make a permanent multifiber optical splice.

Embodiment 4A is the multifiber splice device of either of embodiments 2A or 3 A, wherein the optical adhesive is blue light curable.

Embodiment 5A is the multifiber splice device of any of embodiments 2A-4A, wherein the optical adhesive comprises an adhesive composition containing non-aggregated, surface- modified silica nano-particles dispersed in an epoxy resin.

Embodiment 6A is the multifiber splice device of any preceding embodiment, wherein the body includes a first plurality of alignment channels formed on a major surface therein.

Embodiment 7A is the multifiber splice device of embodiment 1 A, wherein the arched profile includes a generally planar portion at entrance openings at either end of the alignment channel, the alignment channel gently rises between the entrance openings and an

interconnection region centrally located on the body and where the alignment channel crests in a shallow dome within the interconnection region.

Embodiment 8A is the multifiber splice device of any preceding embodiment, wherein the clamping plate is a thin flexible glass clamping plate that is flexed to align and secure terminal ends of the plurality of first and second optical fibers in an interconnection region of the multifiber splice element.

Embodiment 9A is the multifiber splice device of any preceding embodiment, further comprising a means of imparting a pressing force on the clamp plate which causes the clamping plate to flex aligning and securing terminal ends of the plurality of first and second optical fibers in the alignment channels in an interconnection region of the multifiber splice element. Embodiment 10A is the multifiber splice device of embodiment 9A, wherein the means of imparting a pressing force comprises a spring clip.

Embodiment 11 A is the multifiber splice device of embodiment 10A, wherein the means of imparting a pressing force comprises an activation cam.

Embodiment 12A is the multifiber splice device of any preceding embodiment, wherein the body has a substantially rectangular shape.

Embodiment 13 A is the multifiber splice device of any preceding embodiment, wherein the body has a substantially semi-cylindrical shape.

Embodiment 14A is the multifiber splice device of any preceding embodiment, wherein the base plate further comprises funneling entrance openings at both ends of the alignment groove, wherein the entrance openings are wider than the alignment groove.

Embodiment 15A is the multifiber splice device of any preceding embodiment, wherein the plurality of alignment channels are parallel and spaced apart from each other on the major surface of the splice element.

Embodiment 16A is the multifiber splice device of any preceding embodiment, wherein the fiber splice experiences has an insertion loss of less than 0.1 dB.

Embodiment 17A is the multifiber splice device of any preceding embodiment, wherein the multifiber splice has a return loss variation of less than 10 dB when temperature cycled from -40°C to +75°C.

Embodiment 18A is the multifiber splice device of any preceding embodiment, wherein the multifiber splice has a pullout strength of greater than 0.5 lbf per fiber.

Embodiment 19A is the multifiber splice device of any preceding embodiment, wherein the silica material is a net shape cast and cure silica material.

Embodiment 20A is a multifiber ribbon repair device comprising the splice device of any of the previous embodiments.

Embodiment 21 A is a multifiber ribbon fanout cassette comprising the splice device of any of the previous embodiments.

Embodiment IB is an optical cassette that comprises an enclosure having a top, a bottom and a plurality of side walls disposed between the top and the bottom, and an element housing disposed through one of the plurality of sidewalls. A multifiber splice element is disposed in the element housing to interconnect terminal ends of a plurality of outside optical fibers to a plurality terminal ends of fibers disposed within the enclosure, wherein the multifiber splice element has a body, having a plurality of alignment channels configured to receive the plurality of first and second optical fibers in an end-to-end manner; a clamp plate, wherein at least one of the body and clamp plate being formed from a coefficient of thermal expansion matched silica material, and; an optical coupling material disposed in at least a portion of the plurality alignment channels such that the optical coupling material is positioned between the plurality of first and second optical fibers.

Embodiment 2B is the cassette of embodiment IB further comprising an optical coupling material disposed in at least a portion of the plurality alignment channels such that the optical coupling material is positioned between the plurality of first and second optical fibers.

Embodiment 3B is the cassette of either of embodiment IB or 2B, further comprising a plurality of signal paths exiting through one of the plurality of sidewalls.

Embodiment 4B is the cassette of embodiment 3B, wherein each of the plurality of signal paths comprises a connection point at the sidewall where the plurality of signal paths exit the cassette.

Embodiment 5B is the cassette of embodiment 4B, wherein the connection point comprises and optical fiber connector connection point.

Embodiment 6B is the cassette of embodiment 5B, wherein the optical fiber connector connection point is a multifiber connector connection point.

Embodiment 7B is the cassette of embodiment 6B, wherein the optical fiber connector connection point comprises a plurality of single fiber connector connection points.

Embodiment 8B is the cassette of embodiment 7B, wherein the plurality of single fiber connector connection points are paired, wherein the first of the pair of single fiber connection points is designated as a transmit port and the second of the pair of single fiber connection points is designated as a receive port.

Embodiment 9B is the cassette of embodiment 4B, wherein the connection point comprises an optical fiber splice connection point.

Embodiment 10B is the cassette of embodiment 9B, wherein the optical fiber connector connection point is a multifiber splice connection point.

Embodiment 1 IB is the cassette of embodiment 9B, wherein the optical fiber connector connection point comprises a plurality of single fiber connector connection points.

Embodiment 12B is the cassette of any of embodiments lB-1 IB, wherein signals carried by the plurality of outside optical fibers are reordered within the cassette such that the signals leave the cassette in a different order than the enter the cassette.

Embodiment 13B is the cassette of embodiment 12B, wherein the optical fibers are reordered to manage the polarity of the signals leaving the cassette. Embodiment 14B is the cassette of any of embodiments 1B-13B, wherein the plurality terminal ends of fibers disposed within the enclosure are factory installed into the multifiber splice element.

Embodiment 15B is the cassette of any of embodiments 1B-13B, wherein the plurality terminal ends of fibers disposed within the enclosure are field installed into the multifiber splice element.

Embodiment 16B is the cassette of any of embodiments 1B-13B, wherein all optical connections within the cassette are made and the cassette is factory assembled such that an interior of the cassette is inaccessible thereafter.

Embodiment 1C is a method of splicing a plurality of first optical fibers to a plurality of second optical fiber, comprising inserting the plurality of first fibers into a plurality of alignment channels formed in a multifiber silica splice element, wherein the plurality of alignment channels are configured to receive the plurality of first and the second optical fibers in an end-to-end manner, inserting the plurality of second fibers into the plurality of alignment channels such that terminal ends of the plurality first fibers are brought in close proximity to ends of the plurality of second fibers; and exerting a pressing force on a flexible clamp plate to cause the clamping plate to flex aligning and securing terminal ends of the plurality of first and second optical fibers in the alignment channels in an interconnection region of the multifiber splice element.

Embodiment 2C is the method of the embodiment 1C, further comprising the step of curing an optical adhesive disposed in the plurality of alignment channels by directing an effective amount of actinic radiation towards the optical adhesive.

Embodiment 3C is the method of the embodiments 2C, wherein the curing step comprises directing an effective amount of blue light through at least one of the plates towards the optical adhesive.

Embodiment ID is a multifiber splice device for splicing a plurality of first and second optical fibers. The multifiber splice device comprises a multifiber splice element having a body, having a plurality of alignment channels configured to receive the plurality of first and second optical fibers in an end-to-end manner, a clamp plate, wherein the clamping plate is a thin flexible glass clamping plate that is flexed to align and secure terminal ends of the plurality of first and second optical fibers in an interconnection region of the multifiber splice element; wherein at least one of the body and clamp plate being formed from a low coefficient of thermal expansion silica material, and an optical coupling material is disposed in at least a portion of the plurality alignment channels such that the optical coupling material is positioned between the plurality of first and second optical fibers. Embodiment 2D is the multifiber splice device of embodiment ID, wherein the optical coupling material is at least one of an index matching material or an optical adhesive.

Embodiment 3D is the multifiber splice device of embodiment 2D, wherein the optical adhesive is curable via actinic radiation to make a permanent multifiber optical splice.

Embodiment 4D is the multifiber splice device of either of embodiments 2D or 3D, wherein the optical adhesive is blue light curable.

Embodiment 5D is the multifiber splice device of any of embodiments 2D-4D, wherein the optical adhesive comprises an adhesive composition containing non-aggregated, surface- modified silica nano-particles dispersed in an epoxy resin.

Embodiment 6D is the multifiber splice device of any preceding embodiment, wherein the body includes a first plurality of alignment channels formed on a major surface therein.

Embodiment 7D is the multifiber splice device of any preceding embodiment, wherein each of the first plurality of alignment channel has an arched profile.

Embodiment 8D is the multifiber splice device of embodiment 7D, wherein the arched profile includes a generally planar portion at entrance openings at either end of the alignment channel, the alignment channel gently rises between the entrance openings and an

interconnection region centrally located on the body and where the alignment channel crests in a shallow dome within the interconnection region.

Embodiment 9D is the multifiber splice device of any preceding embodiment, further comprising a means of imparting a pressing force on the clamp plate which causes the clamping plate to flex aligning and securing terminal ends of the plurality of first and second optical fibers in the alignment channels in an interconnection region of the multifiber splice element.

Embodiment 10D is the multifiber splice device of embodiment 9D, wherein the means of imparting a pressing force comprises a spring clip.

Embodiment 1 ID is the multifiber splice device of embodiment 9D, wherein the means of imparting a pressing force comprises an activation cam.

Embodiment 12D is the multifiber splice device of any preceding embodiment, wherein the body has a substantially rectangular shape.

Embodiment 13D is the multifiber splice device of any preceding embodiment, wherein the body has a substantially semi-cylindrical shape.

Embodiment 14D is the multifiber splice device of any preceding embodiment, wherein the base plate further comprises funneling entrance openings at both ends of the alignment groove, wherein the entrance openings are wider than the alignment groove. Embodiment 15D is the multifiber splice device of any preceding embodiment, wherein the plurality of alignment channels are parallel and spaced apart from each other on the major surface of the splice element.

Embodiment 16D is the multifiber splice device of any preceding embodiment, wherein the fiber splice experiences has an insertion loss of less than 0.1 dB.

Embodiment 17D is the multifiber splice device of any preceding embodiment, wherein the multifiber splice has a return loss variation of less than 10 dB when temperature cycled from -40°C to +75°C.

Embodiment 18D is the multifiber splice device of any preceding embodiment, wherein the multifiber splice has a pullout strength of greater than 0.5 lbf per fiber.

Embodiment 19D is the multifiber splice device of any preceding embodiment, wherein the silica material is a net shape cast and cure silica material.

Embodiment 20D is a multifiber ribbon repair device comprising the splice device of any of the previous embodiments.

Embodiment 2 ID is a multifiber ribbon fanout cassette comprising the splice device of any of the previous embodiments.

Embodiment IE is a plug and splice interconnect system that comprises a multi-fiber splice device comprising an element housing and a multifiber splice element disposed in the element housing to interconnect terminal ends of optical fibers of a pair of fiber ribbons, wherein the multifiber splice element has a body, having a plurality of alignment channels configured to receive the plurality of first and second optical fibers in an end-to-end manner; a clamp plate, wherein at least one of the body and the clamp plate is formed from a low coefficient of thermal expansion silica material; and a multifiber bare-fiber holder that houses prepared ends of the optical fibers from one of the pair of ribbons, wherein the prepared ends are introduced into the alignment channels of multifiber splice element when the multifiber bare-fiber holder is connected to multi-fiber splice device.

Embodiment 2E is the interconnection system of embodiment IE, wherein a multi-fiber splice device wherein the clamping plate is a thin flexible glass clamping plate that is flexed to align and secure terminal ends of optical fibers in an interconnection region of the multifiber splice element.

Embodiment 3E is the interconnection system of either of embodiments IE or 2E, wherein the plurality of alignment channel has an arched profile. Embodiment 4E is the interconnection system of any of embodiments 1E-3E, at least one of the body and clamp plate being formed from a low coefficient of thermal expansion silica material.

Embodiment 5E is the interconnection system device of any of embodiments 1E-4E, wherein the silica material is a net shape cast and cure silica material.

Embodiment 6E is the interconnection system device of any of embodiments 1E-4E, wherein multifiber bare-fiber holder comprises a ribbon anchor, a fiber alignment mechanism to align and protect the prepared ends of optical fibers from one of the pair of fiber ribbons and a locking mechanism to secure the multifiber bare-fiber holder to the multi-fiber splice device.

Embodiment 7E is the interconnection system device of embodiment 6E, wherein the fiber alignment mechanism is a fiber alignment collar that is slideably mounted in the multifiber bare-fiber holder.

Embodiment 8E is the interconnection system device of embodiment 7E, wherein the fiber alignment collar is free to slide longitudinally with respect to the ribbon anchor from a first or extended position to protect the prepared ends of optical fibers from one of the pair of fiber ribbons to a retracted position that exposes the prepared ends so that they can be inserted into the alignment channels of the multifiber splice element.

Embodiment 9E is the interconnection system device of any of embodiments 6E-8E, wherein the locking mechanism is a locking sleeve configured to connect to the element housing of the multifiber splice device.

Embodiment 10E is the interconnection system device of any of embodiments 6E-8E, the locking mechanism is a locking sleeve configured to connect to the element housing of the multifiber splice device via a bayonet connection mechanism.

Embodiment 1 IE is the interconnection system of any of embodiments 1E-10E, further comprising an optical coupling material disposed in at least a portion of the plurality alignment channels such that the optical coupling material is positioned between the plurality of first and second optical fibers.

Embodiment 12E is the interconnection system of any of embodiments lE-1 IE, wherein one of the pair of fiber ribbons comprises a fanout portion and another of the pair of fiber ribbons comprises a transmission portion.

Embodiment 13E is the interconnection system of embodiment 12E, wherein terminal ends of optical fibers of a fanout portion are factory installed into the alignment channels of the multifiber splice element. Embodiment 14E is the interconnection system of embodiment 12E, wherein terminal ends of optical fibers of a transmission portion are factory installed into the multifiber bare-fiber holder.

Embodiment 15E is the interconnection system of embodiment 12E, wherein the terminal ends of optical fibers of a transmission portion are factory installed into the alignment channels of the multifiber splice element.

Embodiment 16E is the interconnection system of embodiment of embodiment 12E, wherein terminal ends of optical fibers of a fanout portion are factory installed into the multifiber bare-fiber holder.

Embodiment 17E is the interconnection system of embodiment any of embodiments 12E- 16E, wherein the connection of the multifiber splice device and the multifiber bare-fiber holder form an optical fiber harness assembly.

Embodiment 18E is the interconnection system of any of embodiments 1E-17E, wherein the connection of the multifiber splice device and the multifiber bare-fiber holder are disposed at least partially in a sidewall of a housing to form a fanout cassette.

Embodiment 19E is the interconnection system of any of embodiments 1E-18E, wherein the multifiber splice device and the multifiber bare-fiber holder are connected in the field.

Embodiment 20E is the interconnection system of any of embodiments 1E-18E, wherein the multifiber splice device and the multifiber bare-fiber holder are connected in the factory.

Various modifications, equivalent processes, as well as numerous structures to which the present invention may be applicable will be readily apparent to those of skill in the art to which the present invention is directed upon review of the present specification.