WO2013150089A1

WO2013150089A1 - Mechanical alignment device for positioning optical fibers

Info

Publication number: WO2013150089A1
Application number: PCT/EP2013/057073
Authority: WO
Inventors: Jan Watte; Stefano Beri; Juergen Van Erps; Michael VERVAEKE; Christof Debaes; Hugo Thienpont
Original assignee: Tyco Electronics Raychem Bvba
Priority date: 2012-04-04
Filing date: 2013-04-04
Publication date: 2013-10-10

Abstract

A micro -mechanical positioning system may be used to precisely position a bare optical fiber (50, 150A, 150B, 251, 253) for optical coupling. A plurality of alignment fingers (40, 40A-40D, 40', 407, 407A-407D) can be used to provide support to the optical fiber (50, 150A, 150B, 251, 253) as well as to center and/or align the optical fiber along a predetermined axis. The alignment fingers (40, 40A-40D, 40', 407, 407A-407D) can engage the optical fiber (50, 150A, 150B, 251, 253) and provide retention of the optical fiber that resists axial movement of the optical fiber.

Description

MECHANICAL ALIGNMENT DEVICE FOR POSITIONING OPTICAL FIBERS

TECHNICAL FIELD

The present disclosure relates generally to mechanical alignment devices. More particularly, the present disclosure relates to mechanical alignment devices for precisely positioning and/or aligning optical fibers.

BACKGROUND

Modern optical devices and optical communications systems widely use fiber optic cables. Optical fibers are strands of glass fiber processed so that light beams transmitted through the glass fiber are subject to total internal reflection wherein a large fraction of the incident intensity of light directed into the fiber is received at the other end of the fiber.

One common type of fiber optic connector includes a ferrule (i.e., a cylindrical plug) mounted at the distal end of a connector body. The ferrule supports an end of an optical fiber which is adhesively bonded within the ferrule. The optical fiber typically includes a polished end face positioned at a distal end of the ferrule. The fiber optic connector also includes a spring that biases the ferrule in a distal direction. To provide an optical coupling between two of the fiber optic connectors, the fiber optic connectors desired to be optically coupled together are inserted within opposite ports of a fiber optic adapter. The fiber optic adapter includes an alignment sleeve that receives and aligns the ferrules of the fiber optic connectors such that the end faces of the optical fibers secured within the ferrules oppose one another with the optical fibers being placed in end-to-end co-axial alignment with one another. In this way, optical signals can be transmitted between the optical fibers. Precision holes are drilled or molded through the center of each ferrule (e.g., a ceramic or metal ferrule) for receiving the corresponding optical fiber. Precise fiber alignment depends on the accuracy of the central hole of each ferrule. Disadvantageously, drilling of such a central hole that is accurate enough for aligning can be difficult. In addition, a connector containing a ferrule has very high manufacturing costs. Therefore looking for adequate alignment solutions containing ferrule less connectors would be more desirable.

V-grooves are commonly used in prior-art devices to co-axially align optical fibers without the use of a ferrule (e.g., see US 6,516,131). In use of a V-groove alignment system, two optical fibers are positioned within the same V-groove so that line contact with the sides of the V-groove functions to align the optical fibers. However, the effectiveness of this technique is dependent upon the optical fibers being aligned having the same outer cladding diameter. Hence, effective alignment using this technique requires the outer cladding diameters of the optical fiber being aligned to be precisely toleranced. Systems using flexible clamping members for providing optical fiber positioning and/or alignment are disclosed at DE 4322660 Al; DE10304977 Al; US 7,166,806 B2; and US 6,595,698 B2.

A need still exists for an improved alignment system for aligning optical fibers.

SUMMARY

The present disclosure relates generally to a micro -mechanical positioning system used to precisely position a bare optical fiber for optical coupling. In certain embodiments, alignment fingers are used to provide support to the optical fiber as well as to center and/or align the optical fiber along a predetermined axis. In certain embodiments, the alignment fingers can engage the optical fiber and provide retention of the optical fiber that resists axial movement of the optical fiber. It will be appreciated that aspects of the present disclosure can be used in a variety of different applications where it is desired to precisely position and retain an optical fiber at a predetermined location. Example applications include fiber-to-fiber mechanical alignment; fiber-to fiber alignment in ferrule-less connection systems, pre-spliced cladding alignment; optical fiber alignment prior to fusion splicing, and fiber-to-optical component alignment. In the case of fiber-to-fiber mechanical alignment, two optical fibers can be coaxially aligned with one another so as to provide a mechanical splice between the two optical fibers such that optical signals can be readily transferred between the two optical fibers. In other embodiments, aspects of the present disclosure can be used to align to optical fibers in preparation for fusion splicing.

In accordance with some aspects, an optical fiber alignment device includes a body defining a through-opening forming a fiber insertion region; and a plurality of alignment fingers radially extending into the through-opening from a circumference of the through- opening. The alignment fingers cooperate to provide passive self-centering to any optical fiber being inserted through the through-opening.

It is an object of the present invention to provide a device and method for aligning two fibers end-to-end. Co-axial alignment can be provided between the optical fibers of two fiber optic connectors so as to provide an optical coupling between the optical fibers. In such an embodiment, the optical connectors can be ferrule-less optical connectors. Co-axial alignment can also be provided between the end of an optical fiber of a fiber optic cable and a stub end of an optical fiber supported by a ferrule. In certain embodiments, fiber alignment devices in accordance with the principles of the present disclosure can accurately align optical fiber while using a minimal number of parts to reduce cost and facilitate assembly.

The term "fiber" as used herein relates to a single, optical transmission element having a core and a cladding. The core is the central, light-transmitting region of the fiber and the cladding is the material surrounding the core to form a guiding structure for light propagation within the core. In some implementations (e.g., single-mode fibers), the core has diameter of 8-12 μιη and a cladding has a diameter of 120-130 μιη. The core and cladding can be coated with a primary coating usually comprising one or more organic or polymer layers surrounding the cladding to provide mechanical and environmental protection to the light-transmitting region. The primary coating may have a diameter ranging e.g. between 200 and 300 μιη. The core, cladding and primary coating usually are coated with a secondary coating, a so-called "buffer", a protective polymer layer without optical properties applied over the primary coating. The buffer or secondary coating usually has a diameter ranging between 300-1100 μιη, depending on the cable manufacturer. In other implementations (e.g., multi-mode fibers), the core has diameter of 50-65 μιη.

The term "light" as used herein relates to electromagnetic radiation, which comprises a part of the electromagnetic spectrum that is classified by wavelength into infrared, the visible region, and ultraviolet.

Index matching gel can be used with alignment devices in accordance with the principles of the present disclosure to improve the optical connection between the open light transmission paths of the first and second optical fibers. The index matching gel preferably has an index of refraction that closely approximates that of an optical fiber is used to reduce Fresnel reflection at the surface of the bare optical fiber ends. Without the use of an index- matching material, Fresnel reflections will occur at the smooth end faces of a fiber and reduce the efficiency of the optical connection and thus of the entire optical circuit.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a plan view of an optical fiber alignment device in accordance with the principles of the present disclosure; Figure 2 is a perspective view of the optical fiber alignment device of Figure 1;

Figure 3 is a cross-sectional view taken along section line 3-3 of Figure 1;

Figure 4 is an alternative optical fiber alignment device in accordance with the principles of the present disclosure;

Figure 5 illustrates a plate incorporating the optical fiber alignment device of Figure i;

Figure 6 illustrates an optical fiber alignment system using a plurality of plates of the type shown at Figure 5;

Figure 7 illustrates another optical fiber alignment system in accordance with the principles of the present disclosure, the embodiment of Figure 7 includes an intermediate layer or plate positioned between two alignment plates;

Figure 8 shows an optical fiber alignment system in accordance with the principles of the present disclosure, the optical fiber alignment system includes alignment plates with mating structures for aligning the plates;

Figure 9 shows another optical fiber alignment system in accordance with the principles of the present disclosure, the system includes plates each having both male and female interconnect/alignment structures;

Figure 10 illustrates an optical fiber alignment system in accordance with the principles of the present disclosure for aligning optical fibers within an optical component;

Figure 11 shows another optical fiber alignment system in accordance with the principles of the present disclosure for aligning optical fibers with an optical component;

Figure 12 shows another example fiber alignment system including two alignment plates which are aligned relative to one another by guide pins;

Figure 13 shows another example fiber alignment system including a plurality of alignment plates which are aligned relative to one another by guide pins; Figure 14 shows another example fiber alignment system including a male alignment plate and at least a first female alignment plate that are aligned relative to one another by guide pins;

Figure 15 shows another example fiber alignment system including two alignment plates which are aligned relative to one another by guide pins;

Figure 16 shows another example alignment plate having a body defining guide pin openings and an alignment structure; and

Figure 17 is an enlarged, front, elevational view of the alignment structure of the alignment plate of Figure 16.

DETAILED DESCRIPTION

In general, the present disclosure is directed to optical fiber alignment devices including deflectable/compressible micro-cantilevers that behave as springs to provide passive self-centering functionality to optical fibers being inserted therethrough. Each alignment device includes a body defining a through-opening. One or more fingers extend radially into the through-opening from a circumference of the through-opening. The fingers cooperate to center an optical fiber during insertion through the through-opening. In some implementations, the fingers are compressible/deflectable. In other implementations, the fingers are mounted to beams that are compressible/deflectable. In other implementations, compressible/deflectable fingers may be mounted to compressible/deflectable beams. The alignment devices enable passive self-centering of fibers having a variety of cross dimensions.

Figures 1-3 show an optical fiber alignment device 20 in accordance with the principles of the present disclosure. The optical fiber alignment device 20 includes a fiber alignment structure 22 having a first side 24 (see Figures 2 and 3) and an opposite second side 26 (see Figures 2 and 3). The fiber alignment structure 22 also includes a frame portion 28 surrounding a fiber alignment opening 30 that extends through the fiber alignment structure 22 from the first side 24 to the second side 26. The frame portion 28 defines a plurality of relief openings 32 (e.g., slots) that extend through the fiber alignment structure 22 from the first side 24 to the second side 26. The relief openings 32 are positioned around the fiber alignment opening 30 such that the frame portion 28 includes a plurality of resilient beams 34 having first sides 36 positioned at the relief openings 32 and second sides 38 positioned at the fiber alignment opening 30. As the term is used herein, "resilient" implies that the structure has at least some elastic characteristics. The term "resilient" is not intended to indicate a perfect elasticity. Rather, the structure may exhibit some plastic deformation as well as resiliency. The fiber alignment structures 22 also includes a plurality of fiber alignment fingers

40 having base ends 42 connected to the resilient beams 34 and free ends 44 that cooperate to define a fiber insertion region 46 of the fiber alignment opening 30. The fiber insertion region 46 surrounds a fiber insertion axis 48 along which an optical fiber 50 (see FIG. 2) is inserted when the optical fiber 50 is inserted into the fiber alignment structure 22. In certain implementations, the free ends 44 of the alignment fingers 40 have a concave tip (i.e., fillet radius) to accommodate the optical fiber 50. The fiber insertion axis 48 extends through the fiber alignment structure 22 from the first side 24 to the second side 26. The optical fiber 50 is shown having a core 50a and a cladding 50b (see Figure 2).

Referring to Figures 1 and 2, the resilient beams 34 have opposite ends 52 that are secured (e.g., integrally connected) with a remainder of the frame portion 28 of the fiber alignment structure 22. The fiber alignment fingers 40 are connected to the resilient beams 34 at locations that are generally centered between the opposite ends 52 of the resilient beams 34.

The fiber alignment fingers 40 have lengths L that preferably extend primarily in a radial direction relative to the fiber insertion axis 48. In the depicted embodiments, the lengths L of the fiber alignment fingers 40 have a pure radial orientation relative to the fiber insertion axis 48. When the optical fiber 50 is inserted into the fiber insertion region 46 along the fiber insertion axis 48, a compressive load is transferred through the fiber alignment fingers 40 in a direction parallel to the lengths L of the fiber alignment fingers 40. This compressive load is transferred from the fiber alignment fingers 40 to the resilient beams 34 thereby causing the resilient beams 34 to elastically deform/flex relative to their opposite ends 52. The elastically deformed resilient beams 34 cause the free ends 44 to apply centering forces that center the optical fiber 50 along the fiber insertion axis 48. Such centering forces also resist axial movement of the optical fiber 50 via friction between the optical fiber 50 and the pre-ends 44 of the fiber alignment fingers 40.

The fiber alignment fingers 40 also have depths D that extend between the first and second sides 24, 26 of the fiber alignment structure 22, and widths W that are perpendicular relative to the depths D and the lengths L. In the depicted embodiment, the widths W of the fiber alignment fingers 40 are larger at the base ends 42 of the fiber alignment fingers 40 as compared to at the free ends 44 of the fiber alignment fingers 40. As shown at Figure 1, the widths W of the fiber alignment fingers 40 taper inwardly as the fiber alignment fingers 40 extend toward the free ends 44.

In certain embodiments, the lengths L of the fiber alignment fingers 40 are from 100 to 800 microns. In certain embodiments, this sizing allows the fiber alignment fingers 40 to be used in a system having a footprint compatible with the footprints of typical fiber optic connectors while still providing the necessary fiber centering and retention forces. In certain embodiments, the depth D of the fiber alignment structure 22 measured between the first and second sides 24, 26 of the fiber alignment structure 22 is from 100 microns to 4 millimeters. In certain implementations, the depth D of the fiber alignment structure measured between the first and second sides 24, 26 of the fiber alignment structure 22 ranges from about 200 microns to about 2,000 microns. In a preferred embodiment, the depth D of the fiber alignment structure measured between the first and second sides 24, 26 of the fiber alignment structure 22 is from 500 microns to 1,000 microns. In other implementations, the fiber alignment structure 22 may have an even greater or lesser depth.

In some implementations, the fiber alignment fingers 40 and the resilient beams 34 have a spring constant ranging from about 10,000 Newtons per meter to about 500,000 Newtons per meter. In certain implementations, the fiber alignment fingers 40 and the resilient beams 34 have a spring constant ranging from about 20,000 Newtons per meter to about 100,000 Newtons per meter. In certain implementations, the fiber alignment fingers 40 and the resilient beams 34 have a spring constant ranging from about 370,000 Newtons per meter to about 470,000 Newtons per meter. In certain embodiments, the fiber alignment fingers 40 and the resilient beams 34 are designed to have a spring constant from 30,000 Newtons per meter to 60,000 Newtons per meter. In an example embodiment, the fiber alignment fingers 40 and the resilient beams 34 provide a spring constant of about 40,000 Newtons per meter.

Referring to Figure 3, the fiber alignment structure 22 can include structure adapted for facilitating inserting the optical fiber 50 into the fiber insertion region 46. For example, the fiber insertion region 46 can have a funnel-shape 47 that converges inwardly toward the fiber insertion axis 48 as the fiber insertion region 46 extends in a fiber insertion direction 60 along the fiber insertion axis 48 (see Figure 3). As shown a Figure 3, the fiber insertion region 46 has a major and minor cross dimensions CD1, CD2 measured in an orientation perpendicular to the fiber insertion axis 48. In a preferred embodiment, the major-cross dimension CD1 is larger than 125 microns and the minor cross dimension CD2 is smaller than 125 microns. In certain embodiments, the minor cross dimension is in the range of 118 to 125 microns, or in the range of 122 to 123 microns.

Referring back to Figure 1 , the fiber alignment fingers 40 can include a first fiber alignment finger 40A, a second fiber alignment finger 40B, a third fiber alignment finger 40C and a fourth fiber alignment finger 40D. The fiber alignment fingers 40A-40D are shown being uniformly angularly spaced about the fiber insertion axis 48. In the depicted embodiment, the first and third fiber alignment fingers 40A, 40C form a first pair of opposing fiber alignment fingers, and the second and fourth fiber alignment fingers 40B and 40D form a second pair of opposing fiber alignment fingers. In this embodiment, the fiber alignment structure 22 includes an even number of fiber alignment fingers with the fiber alignment fingers being arranged in pairs of opposing fiber alignment fingers. The configuration of the alignment fingers allows the optical fiber 50 to be effectively centered on the fiber insertion axis 48 regardless of the outer diameter defined by the cladding of the fiber 50. Thus, unlike alignment systems that utilize V-grooves, the alignment system disclosed herein can effectively align optical fibers having different outer cladding diameters. This is significant because when alignment is performed mechanically using a V-groove, the tolerance in the cladding diameter is a main source of optical loss. The use of the self-centering alignment structure disclosed herein eliminates this problem as it allows the centers of the mating optical fibers to be aligned independently of the cladding diameter. In certain embodiments, optical performance can be improved from 0.25db to 0.1 db limited by the eccentricity of the optical cores of the optical fibers. In certain embodiments, the fiber alignment fingers 40 can be configured to flex along their length as the optical fiber 50 is inserted into the insertion region. Such flexing of the lengths of the fiber alignment fingers 40 can provide another source of spring

force/stored energy for directing the optical fiber 50 to the centered position relative to the fiber insertion axis 48 and can also provide spring loading for resisting axial movement of the optical fiber relative to the fiber alignment structure 22. In some implementations, the alignment fingers 40 are configured to flex so that the free ends 44 move laterally relative to the length of the fibers 40. In other implementations, the alignment fingers 40 may be compressible along their length L to flex radially outwardly. Figure 4 shows an alternative fiber alignment structure 22' in accordance with the principles of the present disclosure. The fiber alignment structure 22' is similar to the fiber alignment structure 22, except the fiber alignment structure 22' includes an odd number of fiber alignment fingers 40'. Specifically, the fiber alignment structure 22' is shown having three fiber alignment fingers 40'. Additionally, the fiber alignment structure 22' is shown having a generally triangular fiber alignment opening 30' and a frame portion 28' that surrounds the generally triangular fiber alignment opening 30'. The fiber alignment structure 22' further includes resilient beams 34' and relief openings 32' corresponding to each side of the fiber alignment opening 30'. In use of any of the optical fiber alignment devices described herein, the optical fiber

50 is inserted into the fiber insertion region 46 along the fiber insertion axis 48. Preferably, the optical fiber 50 is initially inserted into the funnel structure 47 of the fiber insertion region 46 at the second side 26 of the fiber alignment structure 22. In this way, funnel structure 47 assists in guiding the optical fiber 50 toward the fiber insertion axis 48.

Continued insertion of the optical fiber 50 in the fiber insertion direction 60 causes the optical fiber 50 to slide into the portion of the fiber insertion region 50 having the minor cross dimension CD2. The minor cross dimension CD2 is smaller than the outer diameter defined by the cladding 50b of the fiber 50. Thus, as the optical fiber 50 is inserted into the minor cross dimension CD2, the fiber alignment fingers 40 are forced radially outwardly. The outward radial movement of the fiber alignment fingers 40 is allowed at least in part by the resilient beams 34, which elastically and/or plastically deform to accommodate the outward radial movement of the fiber insertion fingers 40. Specifically, the resilient beams 34 can flex about their opposite ends 52. When the resilient beams 34 are elastically deformed, the elastic beams 34 provide a spring load which is applied through the fiber alignment fingers 40 to the optical fiber 50. Specifically, the free ends 44 of the fiber alignment fingers 40 engage the optical fiber 50 and apply centering forces equally on four sides of the cladding 50b of the optical fiber 50 so as to center the optical fiber 50 on the fiber insertion axis 48. Friction between the optical fiber 50 and the free ends 44 of the fiber alignment fingers 40 also assist in retaining the optical fiber 50 within the fiber alignment structure 22.

Figure 5 shows an alignment plate 70 that incorporates the fiber alignment structure 22 of Figure 1. The alignment plate 70 includes openings 72 configured for receiving pins (e.g., guide pins, alignment pins, guide members, etc.) that are used to align the alignment plate 70 relative to another structure such as a further alignment plate or an optical component (e.g., a planar wave guide, a beam expander, etc.). In some implementations, the alignment plate 70 has a footprint compatible with a footprint of an existing ferrule (e.g., an MPO ferrule). In certain embodiments, the guide pins can each have a diameter between 300 microns and 1,500 microns, and more preferably between 600 microns and 1,000 microns. By selecting the guide pins to have diameters of about 700 microns, this will ensure mateability with certain legacy connectors such as legacy MPO connectors. Structures such as V-grooves can be incorporated into the opening 72 or elsewhere to facilitate enhancing precise positioning between the guide pins and the pertinent structure provided on the alignment plate.

Figure 6 shows a fiber alignment system 79 including two of the alignment plates 70 which are aligned relative to one another by guide pins 74. Once the plates 70 have been aligned with respect to one another, in certain embodiments, the plates 70 can be connected together by such techniques as laser welding, ultrasonic welding, hot-plate welding, adhesive, mechanical fasteners or other techniques. As shown at Figure 6, the alignment plates 70 are oriented with the first sides 24 of the fiber alignment structures 22 facing each other. In this way, the funnel structures 47 are positioned on opposite sides of the alignment plates 70 and the minor cross-dimension portions CD2 of the fiber insertion regions 46 are positioned adjacent to each other at a fiber interface plane P. In this way, the tolerances of the system are maximized at the fiber interface plane P where an optical coupling can be made between two optical fibers. For example, as shown in Figure 6, first and second optical fibers 150A, 150B are inserted through the alignment plates 70 so that end faces 76 of the optical fibers 150A, 150B oppose one another and are coaxially aligned. The system of Figure 6 can also include additional plates 78 stacked with the alignment plates 70 and aligned by the guide pins 74. In certain embodiments, the plates 78 can provide different functions. For example, the plates 78 can include cleaning layers/materials, dust trapping layers/materials or other materials.

Figure 7 shows an alternative system which is similar to the system of FIG. 6 except an intermediate plate 80 is positioned between the alignment plates 70. In the depicted embodiment, the intermediate plate 80 functions as a spacer that prevents physical contact between the end faces of the optical fibers 150A, 150B that are placed in coaxial alignment by the alignment plates 70. In certain embodiments, the intermediate plate can be a relatively hard material such as poly methyl, metha crylate (acrylic glass) or another material. In still other embodiments, the intermediate layer can be a softer material such as a coupling gel or an index matching material. If the separation layer does not provide index matching capability, index matching materials such as gels, oils or films can be dispensed or otherwise provided. In certain embodiments, micro-optic components (e.g., beam expanders, wave guides, etc.) can be provided between the alignment plates 70 to further improve coupling efficiency.

It will be appreciated that structures other than guide pins can be used to provide alignment between the alignment plates 70. For example, alignment structures can be integrated into the alignment plates 70 such that the alignment plates 70 or other plates can snap together or otherwise couple together. For example, Figure 8 shows alignment plate 70A having male projections 154 that fit within corresponding female recesses 156 defined in alignment plate 70B. By mating the male projections 154 to the female recesses 156, alignment between the plates 70A, 70B can be provided. Furthermore, interconnect structures (e.g., snap fit structures) can be provided on the integral alignment features to allow the plates 70A, 70B to lock or otherwise fasten together.

Figure 9 shows another alignment and coupling arrangement for two alignment plates 70C, 70D. In this embodiment, each of the alignment plates 70C, 70D is provided with a male coupling feature 158 and a female coupling feature 160.

Figure 10 shows the alignment plates 70 being used in combination with an optical component 90. Guide pins 92 are used to provide alignment between the optical component 90 and the plates 70. V-grooves can be fabricated into the optical components to precisely position the center of the optical component relative to the centers of the guide pins 92. As previously described, other layers can be also incorporated into the assembly to provide numerous functions such as fiber protection, improved coupling or minimizing return loss. Figure 11 shows still another embodiment where the fiber alignment structures 22 fit within receptacles 162 integrally formed within an optical component 164.

In the depicted embodiment, the stored energy for applying centering and retention forces to the optical fiber are provided by the cantilevers that support the base ends 42 of the fiber alignment fingers 40. Thus, the stored energy component of the fiber alignment structure 22 is incorporated into the frame portion 28 of the fiber alignment structure 22. In other embodiments, the fiber alignment fingers 40 themselves may flex or bend to provide the required elastic deformation. Such elastic deformation may take place axially along the lengths of the fiber alignment fingers 40 or may be the result of the fiber alignment fingers bending or flexing laterally along the lengths of the fiber alignment fingers 40.

Figure 12 shows another example fiber alignment system 200 including two alignment plates 210 which are aligned relative to one another by guide pins 212. The two alignment plates 210 are sandwiched between two guide plates 240. Each of the alignment plates 210 incorporates a fiber alignment structure 220 that aligns with the opening 245 of the adjacent guide plate 240.

The fiber alignment structure 220 includes a frame portion surrounding a fiber alignment opening 225 that extends through the fiber alignment structure 220 from the first side 224 to the second side 226. The frame portion defines a plurality of relief openings 223 (e.g., slots) that extend through the fiber alignment structure 220 from the first side 224 to the second side 226. The relief openings 223 are positioned around the fiber alignment opening 225 such that the frame portion includes a plurality of resilient beams having first sides positioned at the relief openings 223 and second sides positioned at the fiber alignment opening 225.

The fiber alignment structures 220 also includes a plurality of fiber alignment fingers having base ends connected to the resilient beams and free ends that cooperate to define a fiber insertion region 235 of the fiber alignment opening 225. The fiber insertion region 235 surrounds a fiber insertion axis 238 along which an optical fiber 50 (see FIG. 2) is inserted when the optical fiber 50 is inserted into the fiber alignment structure 220. The fiber insertion region 235 can form a passage having a generally constant cross-dimension along the fiber insertion axis 238.

To facilitate fiber insertion, the guide plates 240 are configured to guide the optical fibers 50 to the fiber insertion region 235 of the alignment structures 220. Each guide plate 240 defines an opening 245 extending through the guide plate 240 from a first side 242 to a second side 244 of the guide plate 240. A cross-dimension (e.g., diameter) of each opening 245 tapers inwardly from the first side 242 to the second side 244 of the respective guide plate 240. The guide plates 240 are arranged so that the first side 242 faces away from the alignment plates 210 and the second side 244 faces towards the alignment plates 210, thereby arranging the openings 245 to funnel towards the alignment plates. In this way, the tolerances of the system are maximized at the fiber interface plane P where an optical coupling can be made between two optical fibers.

Figure 13 shows another example fiber alignment system 250 including a plurality of alignment plates 260 which are aligned relative to one another by guide pins 262. The alignment plates 260 are configured to align two optical fibers 251, 253. In general, the alignment plates 260 of Figure 13 may have any of the fiber alignment structures 22, 22', 220 disclosed herein. The alignment plates 260 are stacked together to provide alignment along a length of the optical fibers 251, 253 being interfaced together. In the example shown, first and second alignment plates 260 are oriented to face each other to define the fiber interface plane P. A first additional plate 260 is oriented in the same direction as the first alignment plate 260 and a second additional plate 260 is oriented in the same direction as the second alignment plate 260.

Using multiple alignment plates 260 to align a single optical fiber enables a reduction in the elastic constant of each individual alignment structure compared to a system using a single alignment plate per fiber. The elastic constant of the resilient beams (i.e., the force applied by the alignment fingers) is multiplied by the number of plates provided. In some implementations, the alignment system 250 uses two plates per optical fiber. In certain implementations, the alignment system 250 uses five plates per optical fiber. In certain implementations, the alignment system 250 uses ten plates per optical fiber. In other implementations, the alignment system 250 may use any even greater number of plates.

Figure 14 shows another example fiber alignment system 300 including a male alignment plate 310 and at least a first female alignment plate 320 that are aligned relative to one another by guide pins 312. The guide pins 312 protrude upwardly from the male alignment plate 310. In certain implementations, the guide pins 312 are molded to the male alignment plate 310 to facilitate alignment of the two plates 310, 320. Each female alignment plate 320 defines guide apertures 322 that are positioned to align with the guide pins 312 of the male alignment plate. The guide pins 312 have a length (height) that is sufficient to accommodate a desired number of female alignment plates 320. In certain implementations, one or more of the female alignment plates 320 may face in a common direction with the male alignment plate 310 to form an alignment arrangement for one optical fiber. In such implementations, one or more female alignment plates 320 are oriented in an opposite direction to face the male and female alignment plates 310, 320 to align a mating optical fiber. Figure 15 shows another example fiber alignment system 330 including two alignment plates 340 which are aligned relative to one another by guide pins 350. Each alignment plate 340 includes a fiber alignment structure 345 configured to align an optical fiber extending through an insertion region. In some implementations, at least one of the alignment plates 340 also defines pin alignment structures 342 that are configured to align the guide pins 350. In the example shown, a top one of the plates 340 includes molded guide pins 350 and a bottom one of the plates 340 includes the pin alignment structures 342. In other implementations, both of the plates 340 may include the pin alignment structures 342. The pin alignment structures 342 may have the same structure as any of the fiber alignment structures disclosed herein. In the example shown, each of the pin alignment structures 342 has the same structure as the fiber alignment structure 345. In certain implementations, the pin alignment structures 342 are substantially larger than the fiber alignment structures 345 since the pins 350 have a substantially larger cross dimension than the optical fibers. In certain implementations, the pin alignment structures 342 have shorter alignment fingers than the corresponding fiber alignment structures.

Figure 16 shows another example alignment plate 400 having a body 401 defining guide pin openings 402 and an alignment structure 405. The alignment structure 405 defines an opening 406 extend between front and rear sides 403, 404 of the plate body 401.

Protruding sections extend radially into the opening 406 to form alignment fingers 407. In the example shown, three alignment fingers 407 extend radially into the opening 406. In other implementations, however, a greater or lesser number of fingers 407 may extend into the opening 406.

In some implementations, the alignment plate body 401 is formed from an elastic or otherwise resilient material. Accordingly, the alignment fingers 407 are each compressible at least along a compression axis AC1, AC2, AC3 extending radially into the opening 406. In other implementations, only a portion of the plate body 401 surrounding the alignment structure 405 is formed from a compressible material. In still other implementations, the plate body 401 is formed from a deformable material. Figure 17 is an enlarged, front, elevational view of the alignment structure 405 of the alignment plate 400. The alignment structure 405 is formed by etching away material from the plate body 401. In the example shown, the opening 406 is formed by etching three circles 406A, 406B, 406C into the body 401. The circles 406A, 406B, 406C are positioned to define three pointed sections 407 A, 407B, 407C that form the fingers 407 of the alignment structure 405. In other implementations, a greater or lesser number of circles may be etched into the plate body 401. For example, in one implementation, four fingers 407 may be formed by etching four circles into the body 401. In still other implementations, other shapes may be etched into the plate body 401 to form the fingers 407.

In some implementations, the etching is performed using deep proton writing (DPW) or other such material removal techniques. For example, in Figure 17, each of the circles 406A-406C corresponds with a bombardment zone for high energy protons shot through a mask. The bombarded regions are then etched to provide a chamfered structure. A mold can be constructed around the chamfered structure to dull the pointed edges between the circles to planes that can push against an optical fiber without damaging the fiber. In other implementations, other etching, printing, or molding techniques may be used.

It will be appreciated that the fiber alignment structures can be made of a variety of different material types. Example materials include metal materials, and polymeric materials (e.g., polysulfone). A preferred material is a thermo -plastic material such as acrylic glass or other thermo-plastic. In other implementations, the plates and/or structures may be formed from metal. In still other implementations, the plates and/or structures may be formed from rubber, foam, or another compressible material. In certain embodiments, the fiber alignment structures can be manufactured using methodology such as etching, hot embossing, and micro-injection molding or other molding processes.

Parts List

20 an optical fiber alignment device

22 a fiber alignment structure

24 a first side

26 an opposite second side

28 a frame portion

30 a fiber alignment opening

32 a plurality of relief openings

34 a plurality of resilient beams

36 first sides

38 second sides

40, 40A-40D a plurality of fiber alignment fingers

42 base ends

44 free ends

46 a fiber insertion region

47 a funnel-shape

48 a fiber insertion axis

50 an optical fiber

50a a core

50b a cladding

52 opposite ends

60 a fiber insertion direction

D depth of fiber alignment structure

L length of alignment fingers

W width of alignment fingers

P a fiber interface plane

CD1 major cross dimension of the fiber insertion region

CD2 minor cross dimension of the fiber insertion region

22' an alternative fiber alignment structure

28' a frame portion

30' fiber alignment opening

32' relief openings

34' resilient beams

40' fiber alignment fingers 70, 70A-70D an alignment plate

72 openings

74 guide pins

78 additional plates

79 a fiber alignment system

80 an intermediate plate

90 an optical component

92 guide pins

150A a first optical fiber

150B a second optical fiber

154 male projections

156 female recesses

158 a male coupling feature

160 a female coupling feature

162 receptacles

164 an optical component

200 another example fiber alignment system

210 alignment plates

212 guide pins

220 fiber alignment structure

223 a plurality of relief openings

224 first side

225 a fiber alignment opening

226 second side

235 fiber insertion region

238 a fiber insertion axis

240 guide plates

242 a first side

244 a second side

245 opening

250 another example fiber alignment system

251 optical fiber

253 optical fiber

260 a plurality of alignment plates 262 guide pins

300 another example fiber alignment system

310 a male alignment plate

312 guide pins

320 a first female alignment plate

322 guide apertures

330 another example fiber alignment system

340 alignment plates

342 pin alignment structures

345 a fiber alignment structure

350 guide pins

400 another example alignment plate

401 a body

402 guide pin openings

403 front side

404 rear side

405 an alignment structure

406, 406A-406C opening

407, 407A-407D alignment fingers

AC1, AC2, AC3 compression axes

Claims

CLAIMS:

1. An optical fiber alignment device (20) comprising:

a fiber alignment structure (22, 22', 79, 220, 345, 405) having a first side (24, 224) and an opposite second side (26, 226), the fiber alignment structure (22, 22', 220, 345, 405) including a frame portion (28, 28') surrounding a fiber alignment opening (30, 30', 225, 406) that extends through the fiber alignment structure (22, 22', 79, 220, 345, 405) from the first side (24, 224) of the fiber alignment structure (22, 22', 220, 345, 405) to the second side (26, 226) of the fiber alignment structure (22, 22', 79, 220, 345, 405), the frame portion (28, 28') defining a plurality of relief openings (32, 32', 223) that extend through the fiber alignment structure (22, 22', 79, 220, 345, 405) from the first side of the fiber alignment structure (22, 22', 79, 220, 345, 405) to the second side of the fiber alignment structure (22, 22', 79, 220, 345, 405), the relief openings (32, 32', 223) being positioned around the fiber alignment opening (30, 30', 225, 406) such that the frame portion (28, 28') includes a plurality of resilient beams (34, 34') having first sides (36) positioned at the relief openings (32, 32', 223) and second sides (38) positioned at the fiber alignment opening (30, 30', 225, 406), the fiber alignment structure (22, 22', 79, 220, 345, 405) also including a plurality of fiber alignment fingers (40, 40A-40D, 40') that project from the frame portion (28, 28') into the fiber alignment opening (30, 30', 225, 406), the fiber alignment fingers (40, 40A-40D, 40') having base ends (42) connected to the resilient beams (34, 34') and free ends (44) that cooperate to define a fiber insertion region (46, 235) of the fiber alignment opening (30, 30', 225, 406), the fiber insertion region surrounding a fiber insertion axis (48, 238) along which an optical fiber (50, 150A, 150B, 251, 253), is inserted when the optical fiber is inserted into the fiber alignment structure (22, 22', 79, 220, 345, 405), the fiber insertion axis extending though the fiber alignment structure (22, 22', 220, 345, 405) from the first side to the second side of the fiber alignment structure (22, 22', 79, 220, 345, 405).

2. The optical fiber alignment device (20) of claim 1, wherein the fiber alignment fingers (40, 40A-40D, 40') have lengths which extend in a radial direction relative to the fiber insertion axis (48, 238).

3. The optical fiber alignment device (20) of claim 2, wherein the fiber alignment fingers (40, 40A-40D, 40') have depths that extend between the first and second sides of the alignment structure (22, 22', 79, 220, 345, 405), and widths that are perpendicular relative to the depths and the lengths.

4. The optical fiber alignment device (20) of claim 3, wherein the widths of the fiber alignment fingers (40, 40A-40D, 40') are larger at the base ends of the fiber alignment fingers as compared to at the free ends of the fiber alignment fingers (40, 40A-40D, 40').

5. The optical fiber alignment device (20) of any of claims 1-4, wherein the lengths of the fiber alignment fingers (40, 40A-40D, 40') are from 100 to 800 microns.

6. The optical fiber alignment device (20) of any of claims 1-5, wherein a depth of the fiber alignment structure (22, 22', 79, 220, 345, 405) measured between the first and second sides of the fiber alignment structure (22, 22', 79, 220, 345, 405) is from 100 microns to 4 millimeters.

7. The optical fiber alignment device (20) of any of claims 1-5, wherein a depth of the fiber alignment structure (22, 22', 79, 220, 345, 405) measured between the first and second sides of the fiber alignment structure (22, 22', 79, 220, 345, 405) is from 500 microns to 1000 microns.

8. The optical fiber alignment device (20) of any of claims 1-7, wherein each of the resilient beams (34, 34') has a spring constant ranging from about 10,000 Newtons/meter to about 500,000 Newtons/meter.

9. The optical fiber alignment device (20) of any of claims 1-7, wherein each of the resilient beams (34, 34') has a spring constant ranging from about 30,000 Newtons/meter to about 60,000 Newtons/meter.

10. The optical fiber alignment device (20) of any of claims 1-9, wherein the fiber insertion region (46, 235) has a funnel-shape that converges inwardly toward the fiber insertion axis (48, 238) as the fiber insertion region (46, 235) extends in a fiber insertion direction along the fiber insertion axis (48, 238).

11. The optical fiber alignment device (20) of any of claims 1-10, wherein the fiber insertion region (46, 235) has major and minor cross-dimensions measured in an orientation perpendicular to the fiber insertion axis (48, 238), the major and minor cross-dimensions being separated by a spacing that extends along the fiber insertion axis (48, 238), the major cross-dimension being larger than 125 microns and the minor cross-dimension being smaller than 125 microns.

12. The optical fiber alignment device (20) of claim 11, wherein the minor cross- dimension is in the range of 118 to 124 microns.

13. The optical fiber alignment device (20) of claim 12, wherein the minor cross- dimension is in the range of 122 to 123 microns.

14. The optical fiber alignment device (20) of any of claims 1-13, wherein the relief openings (32, 32', 223) are relief slots.

15. The optical fiber alignment device (20) of any of claims 1-14, wherein the fiber alignment fingers (40, 40A-40D, 40') include first, second and third fiber alignment fingers (40, 40A-40D, 40').

16. The optical fiber alignment device (20) of claim 15, wherein the first, second and third fiber alignment fingers (40, 40A-40D, 40') are uniformly angularly spaced about the fiber insertion axis (48, 238).

17. The optical fiber alignment device (20) of any of claims 1-14, wherein the fiber alignment fingers (40, 40A-40D, 40') include first, second, third, and fourth fiber alignment fingers (40, 40A-40D, 40').

18. The optical fiber alignment device (20) of claim 17, wherein the first, second, third, and fourth fiber alignment fingers (40, 40A-40D, 40') are uniformly spaced about the fiber insertion axis (48, 238).

19. The optical fiber alignment device (20) of claim 17, wherein the first and third fiber alignment fingers (40, 40A-40D, 40') form a first pair of opposing fiber alignment fingers (40, 40A-40D, 40'), and the second and fourth fiber alignment fingers (40, 40A-40D, 40') form a second pair of opposing fiber alignment fingers (40, 40A-40D, 40').

20. The optical fiber alignment device (20) of any of claims 1-14, wherein the fiber alignment structure (22, 22', 220, 345, 405) includes an even number of the fiber alignment fingers (40, 40A-40D, 40'), and wherein the fiber alignment fingers (40, 40A-40D, 40') are arranged in pairs of opposing fiber alignment fingers (40, 40A-40D, 40').

21. The optical fiber alignment device (20) of any of claims 1-20, wherein the frame portion of the fiber alignment structure (22, 22', 79, 220, 345, 405) is part of an alignment plate (70, 70A-70D, 210, 260, 310, 320, 340, 400) of the fiber alignment structure (22, 22', 79, 220, 345, 405).

22. The optical fiber alignment device (20) of claim 21, wherein the alignment plate (70, 70A-70D, 210, 260, 310, 320, 340, 400) has a footprint compatible with a footprint of an existing ferrule.

23. A method of using the optical fiber alignment device (20) of any of claims 1-22, wherein an optical fiber is inserted into the fiber insertion region (46, 235) along the fiber insertion axis (48, 238), and wherein insertion the optical fiber into the fiber insertion region (46, 235) causes the optical fiber to engage the free ends of the fiber alignment fingers (40, 40A-40D, 40') which causes portions of the fiber alignment structure (22, 22', 220, 345, 405) to elastically deform such that the fiber alignment fingers (40, 40A-40D, 40') exert a retention force on the optical fiber and also axially co-align the optical fiber with the fiber insertion axis (48, 238).

24. An optical fiber alignment device (20) comprising:

a fiber alignment structure (22, 22', 220, 345, 405) having a first side and an opposite second side, the fiber alignment structure (22, 22', 79, 220, 345, 405) including a frame portion (28, 28') surrounding a fiber alignment opening (30, 30', 225, 406) that extends through the fiber alignment structure (22, 22', 79, 220, 345, 405) from the first side of the fiber alignment structure (22, 22', 79, 220, 345, 405) to the second side of the fiber alignment structure (22, 22', 79, 220, 345, 405), the fiber alignment structure (22, 22', 79, 220, 345, 405) also including a plurality of fiber alignment fingers (40, 40A-40D, 40') that project from the frame portion into the fiber alignment opening (30, 30', 225, 406), the fiber alignment fingers (40, 40A-40D, 40') having base ends connected to the frame portion and free ends that cooperate to define a fiber insertion region (46, 235) of the fiber alignment opening (30, 30', 225, 406), the fiber insertion region (46, 235) surrounding a fiber insertion axis (48, 238) along which an optical fiber is inserted when the optical fiber is inserted into the fiber alignment structure (22, 22', 79, 220, 345, 405), the fiber insertion axis (48, 238) extending though the fiber alignment structure (22, 22', 79, 220, 345, 405) from the first side to the second side of the fiber alignment structure (22, 22', 79, 220, 345, 405), and the fiber alignment fingers (40, 40A-40D, 40') having lengths that extend primarily in a radial direction relative to the fiber insertion axis (48, 238).

25. The optical fiber alignment device (20) of claim 24, wherein the fiber alignment structure (22, 22', 79, 220, 345, 405) includes elastic portions that elastically deform when an optical fiber is inserted along the fiber insertion axis (48, 238) into the fiber insertion region (46, 235).

26. The optical fiber alignment device (20) of claim 25, wherein the elastic portions are incorporated into the frame portion of the fiber alignment structure (22, 22', 79, 220, 345,

405).

27. The optical fiber alignment device (20) of claim 25, wherein the elastic portions are provided by the fiber alignment fingers which flex along their lengths during insertion of the optical fiber into the fiber insertion region (46, 235).

28. An optical fiber alignment device (20) comprising:

a fiber alignment structure (22, 22', 79, 220, 345, 405) having a first side and an opposite second side, the fiber alignment structure (22, 22', 79, 220, 345, 405) including a frame portion (28, 28') surrounding a fiber alignment opening (30, 30', 225, 406) that extends through the fiber alignment structure (22, 22', 79, 220, 345, 405) from the first side of the fiber alignment structure (22, 22', 79, 220, 345, 405) to the second side of the fiber alignment structure (22, 22', 79, 220, 345, 405), the fiber alignment structure (22, 22', 79, 220, 345, 405) also including at least four fiber alignment fingers (40, 40A-40D, 40') that project from the frame portion into the fiber alignment opening (30, 30', 225, 406), the fiber alignment fingers (40, 40A-40D, 40') having base ends connected to the frame portion and free ends that cooperate to define a fiber insertion region (46, 235) of the fiber alignment opening (30, 30', 225, 406), the fiber insertion region (46, 235) surrounding a fiber insertion axis (48, 238) along which an optical fiber (50, 150A, 150B, 251, 253) is inserted when the optical fiber is inserted into the fiber alignment structure (22, 22', 79, 220, 345, 405), the fiber insertion axis (48, 238) extending though the fiber alignment structure from the first side to the second side of the fiber alignment structure (22, 22', 79, 220, 345, 405), and the fiber alignment fingers (40, 40A-40D, 40') including an even number of the fiber alignment fingers (40, 40A-40D, 40'), and the fiber alignment fingers (40, 40A-40D, 40') being arranged in pairs of opposing fiber alignment fingers (40, 40A-40D, 40').

29. The optical fiber alignment device (20) of claim 28, wherein the fiber alignment structure (22, 22', 220, 345, 405) includes elastic portions that elastically deform when an optical fiber (50, 150A, 150B, 251, 253) is inserted along the fiber insertion axis (48, 238) into the fiber insertion region (46, 235).

30. The optical fiber alignment device (20) of claim 29, wherein the elastic portions are incorporated into the frame portion (28, 28') of the fiber alignment structure (22, 22', 79, 220, 345, 405).

31. The optical fiber alignment device (20) of claim 29, wherein the elastic portions are provided by the fiber alignment fingers (40, 40A-40D, 40') which flex along their lengths during insertion of the optical fiber (50, 150A, 150B, 251, 253) into the fiber insertion region (46, 235).

32. A system for aligning optical fibers (50, 150A, 150B, 251, 253) comprising:

a first element including a first plate (70, 70A-70D, 210, 260, 310, 320, 340, 400) having a first fiber alignment structure (22, 22', 79, 220, 345, 405) incorporated thereon, the fiber alignment structure (22, 22', 79, 220, 345, 405) being configured to align an optical fiber (50, 150A, 150B, 251, 253) with a predefined axis (48, 238) that passes through the first element;

a second element that aligns with the first element; and

an element alignment structure (72, 74, 92, 154, 156, 158, 160, 212, 262, 312, 322, 342, 350, 402) for aligning the first element relative to the second element.

The system of claim 32, wherein the element alignment structure includes guide pins (74, 92, 212, 262, 312, 350).

34. The system of claim 32, wherein the element alignment structure comprises mating projections (154, 158, 74, 92, 212, 262, 312, 350) and receptacles (156, 160, 72, 322, 342, 402) integrated with the first and second elements.

35. The system of any of claims 32-34, wherein the second element comprises an optical component (90).

36. The system of any of claims 32-34, wherein the second element comprises a second plate (70, 70A-70D, 210, 260, 310, 320, 340, 400) having a second fiber alignment structure (22, 22', 79, 220, 345, 405) incorporated thereon.

37. The system of claim 36, wherein the first and second elements are positioned directly adjacent to one another and are configured for aligning first and second optical fibers (50, 150A, 150B, 251, 253) along a common axis (48, 238).

38. The system of claim 36, wherein the first and second elements are separated by an intermediate plate (80) that prevents physical contact of first and second optical fibers (50, 150A, 150B, 251, 253) aligned along a common axis (48, 238) by the first and second fiber alignment structures (22, 22', 79, 220, 345, 405).

39. The system of any of claims 32-38, further comprising a supplemental function plate (90, 240) connected to the first and second elements, the supplemental function plate (90, 240) providing a function selected from the group consisting of fiber protection, dust protection, index matching, return loss reduction, funneling, and fiber cleaning.

40. An optical fiber alignment device comprising:

a body defining a through-opening (30, 30', 225, 406) forming a fiber insertion region (46, 235); and

a plurality of alignment fingers (40, 40A-40D, 40', 407, 407A-407D) radially extending into the through-opening (30, 30', 225, 406) from a circumference of the through- opening (30, 30', 225, 406), the alignment fingers (40, 40A-40D, 40', 407, 407A-407D) cooperating to provide passive self-centering to any optical fiber (50, 150A, 150B, 251, 253) being inserted through the through-opening (30, 30', 225, 406).

41. The optical fiber alignment device of claim 40, wherein the alignment fingers (40, 40A-40D, 40', 407, 407A-407D) include resilient micro-cantilevers extending radially inwardly from the body.

42. The optical fiber alignment device of claim 41, further comprising a plurality of resilient beams (34, 34'), each resilient beam (34, 34') being coupled to one of the alignment fingers (40, 40A-40D, 40') to provide deflection of the respective alignment finger (40, 40A-40D, 40') along a length of the alignment finger (40, 40A-40D, 40').

43. The optical fiber alignment device of any of claims 40-42, wherein each of the alignment fingers (40, 40A-40D, 40', 407, 407A-407D) is laterally deflectable along a length of the alignment finger (40, 40A-40D, 40', 407, 407A-407D).

44. The optical fiber alignment device of any of claims 40-42, wherein each of the alignment fingers (40, 40A-40D, 40', 407, 407A-407D) is compressible along a length of the alignment finger (40, 40A-40D, 40', 407, 407A-407D).

45. The optical fiber alignment device of claim 40, wherein the through-opening (30, 30', 225, 406) is generally round.

46. The optical fiber alignment device of claim 40, wherein the through-opening (30, 30', 225, 406) is formed from a plurality of overlapping circles (406A-406C).

47. The optical fiber alignment device of any of claims 40-46, wherein the body includes a plate (70, 70A-70D, 210, 260, 310, 320, 340, 400) and the through-opening (30, 30', 225,

406) extends through a depth of the plate (70, 70A-70D, 210, 260, 310, 320, 340, 400).

48. The optical fiber alignment device of claim 47, wherein the plate (70, 70A-70D, 210, 260, 310, 320, 340, 400) defines guide openings (72, 322, 402) through which guide pins (74, 92, 212, 262, 312, 350) may be inserted.

49. The optical fiber alignment device of claim 47, wherein the guide openings (72, 322, 402) form alignment devices (342) for the guide pins (74, 92, 212, 262, 312, 350).

50. The optical fiber alignment device of claim 47, wherein the plate (70, 70A-70D, 210, 260, 310, 320, 340, 400) includes integral guide pins (312) extending upwardly from a major surface of the plate (70, 70A-70D, 210, 260, 310, 320, 340, 400).

51. The optical fiber alignment device of any of claims 47-50, further comprising a plurality of additional plates (70, 70A-70D, 210, 260, 310, 320, 340, 400), each additional plate including a fiber alignment structure (22, 22', 79, 220, 345, 405) defining a through- opening (30, 30', 225, 406) that aligns with the through-opening (30, 30', 225, 406) of the body.

52. The optical fiber alignment device of any of claims 40-50, wherein each of the alignment fingers (40, 40A-40D, 40', 407, 407A-407D) has a depth that ranges from about 200 microns to about 2,000 microns.

53. The optical fiber alignment device of claim 52, wherein the depth ranges from about 500 microns to about 1,000 microns.