MXPA01007219A - Passive platform for holding optical components - Google Patents

Abstract

A passive platform (34) for holding optical components includes a raised loading area comprising a series of finger members (42) disposed along the platform floor (34), the finger members (42) abutting each other and defining between them tunnels for holding optical components in place. A coil guide member (58) projects upward from the floor abutting the raised loading area, the outer perimeter of the coil guide (58) and the raised loading area defining a racetrack region (56) of the floor for winding optical fiber leads extending from optical components being held in the tunnels, the optical fiber passing between the finger members (42) and around the racetrack (56).

Description

STATIC PLATFORM FOR ATTACHING OPTICAL COMPONENTS This application claims the priority benefit under 35 U.S.C. § 120 of the patent application of E.U.A. provisional with Serial No. 60/116182, filed on January 14, 1999, whose content is based and incorporated herein by reference in its entirety.

FIELD OF THE INVENTION The present invention relates generally to improvements in systems and methods for making devices containing optical components, and very particularly to a system and methods for holding optical components in position in a device and for splicing their terminals.

BACKGROUND OF THE INVENTION Devices and systems employing optical fiber almost always include several optical components that must be interconnected to form an optical path for data transmission. In one approach, the optical components are mounted on a printed circuit board, and then the fiber optic terminals are spliced. However, the splicing procedure is complicated due to the relative fragility of the optical fiber, which can be damaged by bending, excessive tension or other forces. The attenuation of excess signals due to the folding of the fiber is also important. In addition, the splicing procedure may require more than one attempt, if it is determined that the splice was not performed well. In this case, the improper connection must be broken, the terminals must be cut again and a new connection made. Finally, the fiber continuous loop resulting from a splice must be adequately concealed to avoid damage to the fiber. Figure 1 is a perspective view of an approach for mounting an optical component 10 on a strip. The optical component 10 includes fiber optic terminals 12 extending from either end. A cable tie 14, or loop, is used to join the optical component 10 to a fastener 16, which is made from a polymer filled with glass or other suitable material whose coefficient of thermal expansion is close to that of the optical fiber , that is moldable and can be machined, but that it remains rigid, and has other useful properties. Finally, the fastener 16 is fixed to a strip by a pair of plastic edges 18. This procedure is carried out for all the optical components used in the device being processed. Once all the optical components on the terminal board have been securely mounted, then their fiber terminals must be spliced together to create an optical path for data transmission. However, the task of splicing fiber optic terminals is much more complex than splicing the terminals of electrical components.

The splicing task is almost always accurate. If the cores of the two spliced fiber terminals are not properly aligned, the optical path can be interrupted. In that case, the unsuitable splice must be broken and another splice must be made. In this way, fiber optic terminals tend to be quite long compared to the terminals of electrical components in order to give a worker an adequate amount of fiber to make several attempts at an appropriate splice. However, in turn, this means that the splicing of two optical component terminals results in a continuous fiber loop, the length of which depends on the amount of fiber needed to achieve an appropriate splice. Since optical fiber is easily damaged, it is generally not desirable to have long fiber loops that float freely within an optical device. Instead, the fiber loops resulting from splices should be hidden so that they do not damage the fiber by bending, tension or other mechanical forces. Figure 2 is a partial perspective view of a system for controlling the continuous optical fiber loops that result in the splicing of optical terminals. The system provides a matrix of curved guides 20, 22a-d, made of a polymer filled with glass or other suitable material, which are mounted on a strip 24. As described below, the optical fiber loops resulting from splices are protected from damage by rolling them in the curved guides in a predetermined pattern. The length of these loops is accurately measured using grids 28a and 28b, so that an optimum level of play is maintained in the loops after being wound in the curved guides, the tension in the loops is sufficient to hold them in place in the loops. guides without causing damage to the fiber or degrade the optical characteristics of the fiber. The curved guide array includes a group of six central roll guides 20 which are positioned to form a central roll. These central roll guides 20 are formed, and are positioned in mutual relation, so that the optical fiber can be wound around them without causing damage to the fiber. In addition, the curved guide array includes pairs of auxiliary guides 22 a-b, 22 c-d which are mounted on the strip 24 on either side of each optical component 10 a, 10 b. Each of these pairs of auxiliary curved guides is formed and positioned in relation to the central roll and the optical components, so that the auxiliary curved guides, 22a-b, 22c-d provide safe winding paths for the optical fiber terminals 12 from their resive optical components 2a-b, 22c-d to the central roll. 10a, 10b The functions of the central roll guides 20 can be better understood with reference to a sfic example. Figure 2 illustrates the first and second optical components 10a, 10b, on the strip 24. (For reasons of clarity only one fastener 16a is illustrated, although in a real device each optical component is held on its own fastener). Each of these optical components 10a, 10b has a pair of optical fiber terminals 12a-b, 12c-d, extending from either end. In this example, a first terminal 12a, extending from the left end of the first optical component 10a, is connected to a second terminal 12b, which extends from the right end of the second optical component 10b. Before actual splicing of the two terminals, each terminal must first be accurately measured and then trimmed so that the fiber continuous loop resulting from the splice is of the correct length. The measuring grids 28a, 28b are located on the strip 24 to allow the worker to determine precisely the point at which the two terminals 12a, 12d are to be spliced. Of course, the point chosen for the splice 30 must provide clearance for a splice sleeve 26 between the central roll guides 20. Once the splice point is determined, using a measurement grid, the length of the first terminal 12a is marked and the second terminal 12d along the measurement grid. The terminals 12a, 12d are then peeled, cleaned and split at the marked splice point, so that the terminals will meet at the appropriate point and the splice sleeve 26 is on a straight execution. If the operation is carried out successfully, the splice sleeve 26 is then acrylated at the location on the splice 30, to form a long continuous fiber loop 32 extending from the left end of the first component 10a to the right end of the splice sleeve 30. second component 10b. If the splice 30 is properly measured and executed, the length of the continuous loop 32 is such that it will fit over the guides in central rolls 20, and the splice sleeve 26 is removed to its predetermined position. The strip includes rows of optical components 10 with terminals 12 extending out of either end. Since the position of each optical component is fixed and since the splice point for each pair of terminals must be measured and executed carefully within a narrow tolerance, this method for splicing fiber optic terminals is called the fiber wrapping process. " deterministic. " As the complexity and number of optical communication system modules increases, several disadvantages of the deterministic procedure have become evident. First, the method described above for wrapping fiber requires a high degree of skill on the part of the worker performing the splicing procedure. The procedure for splicing optical fiber is a careful and difficult task that is complicated by trying to achieve sufficient fiber clearance after re-wrapping it in the guides in central rolls. If the fiber is too tight, loss of light may occur and even the fiber may break. If the fiber is too loose, it can slip out of the guides and play inside the device, which can cause other components to press it or otherwise damage it. Second, the method described above requires the use of a rigid platform to make an assembly that largely has optical components and relatively few electronic components.

Static platforms can be made with less expensive materials, which is cheaper. Third, the loading of a platform with rigid guides and fasteners is a laborious and time-consuming procedure. Finally, it is not efficient to go through the arduous loading, splicing and wrapping process only to know in a final test that a component loaded at the beginning is not operable and should be replaced. These and other matters are addressed in the invention described herein. The optical components are loaded in a specially designed static platform module which is preferably made of foam, elastomer or other workable material. In a first embodiment of this invention, the platform is made from a fairly dense foam material, the example of which is a foam having an approximate density of 64.07 gram / liter. The foam is a very economical material; Even manufactured, its cost is much lower than the rigid guides and fasteners on a printed circuit board, as described above. The foam will not damage the optical fiber, even if it has a rigid texture. At present, to address these problems, a so-called "deterministic" system can be used, in which the position of the optical component is fixed, for example, by a firm assembly in place on a strip, which requires that the splice be perform at a precise location at the ends of the pairing fiber terminals. As described below, this system has several disadvantages, due to the cost and the high degree of skill necessary to execute the splice in the proper position. The present invention addresses these and other disadvantages.

BRIEF DESCRIPTION OF THE INVENTION A first embodiment of the invention provides a platform for holding optical components and their spliced terminals. The platform includes an embossed load area comprising a series of fasteners placed along the floor of the platform to hold optical components in place. Furthermore, the platform includes a roll guide element projecting upwards from the floor, adjacent to the fastening elements, the outer perimeter of the roll guide and the fastening elements define a region of the floor track, inside the floor. which the fiber optic terminals are wound. The platform module of the present invention results in advantages over the packaging of the optical device of the prior art. For example, splices between the components loaded in the platform module are made within the favorable limits of the platform module fiber. Once the splices are completed successfully, the module joins as a single unit on a terminal strip or, alternatively, on a unification busbar architecture. After having attached the module to the terminal strip, any additional splicing can be performed between the components within the platform and the components mounted on the terminal strip within the platform. Another advantage of the present invention is the concept of "free fiber path" modalized in the method that is used to load the components and splice their terminals. The fiber terminals are measured and marked before splicing, however, since the static foam platform uses a "track" to accommodate the fibers instead of wrapping them in the rigid guides, it is no longer necessary to locate the splice in a Fixed and precise point on the strip to achieve the desired result. Instead, the static foam platform provides a relatively wide variety of acceptable locations for the splice point, as described in more detail below. Another advantage of one embodiment of the present invention is the ability to employ an elastic material, the example of which is soft foam from which the platform module is made. The use of a soft foam material protects the fibers from the common problems of sharp edges that can cut, bend or otherwise interrupt the functionality of the fibers. This material is easy to form and consequently offers greater economy than the use of polymers filled with machine-made or molded glass. In addition, the splicing of the fiber optic terminals becomes easier because they do not require very precise lengths; therefore the assembly time and the related production costs decrease.

Another advantage of the present invention as it is modalized in a platform concept is that the fair winding of optical fibers around rigid guides is no longer required. This is because the outer walls retain fibers inside the track; in this way, the losses associated with the just winding are eliminated. Another advantage of the present invention as it is modalized in the modularization of optical circuit components allows the testing of modules before the final assembly. This module test facilitates the location of non-functional problems or modules before assembling a complex optical device that has a large number of components. Additional features and advantages of the invention will be explained in the following detailed description, and will be readily apparent to those skilled in the art from the description or will be recognized by practice of the invention, as described in the description. written and the claims of the same, as well as the attached drawings. It should be understood that the foregoing general description and the following detailed description are only examples of the invention and are intended to provide a general overview or framework for understanding the nature and character of the invention as claimed. The accompanying drawings are included to provide another understanding of the invention and are incorporated and constitute a part of this specification. The drawings illustrate one or more embodiments of the invention and together with the description serve to explain the principles and operation thereof.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of a system for mounting an optical component on a strip. Figure 2 is a partial perspective view of a strip that modalizes a system for splicing fiber optic terminals and hiding the resulting continuous loop of fiber. Figure 3 is a perspective view of a static platform in which the present invention is modalized. Figure 4 is a perspective view of a first embodiment of retention elements that will be employed in conjunction with the static platform illustrated in Figure 3. Figure 5 is a flow diagram of a splice method for use with the illustrated static platform in Figure 3. Figure 6 is a top view of a strip incorporating the static platform illustrated in Figure 3. Figure 7 is a perspective view of a second embodiment of a static platform in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION In the following, the present invention will be described in greater detail with reference to the accompanying drawings, in which the preferred embodiments of the present invention are illustrated. However, the invention described can be modalized in var ways and should not constitute a limit to the exemplary embodiments explained herein. Instead, these representative embodiments are described in detail, so that this description will be sufficient and complete and will convey the structure, operation, functionality and potential scope of the applicability of the invention to those skilled in the art. Figure 3 is a perspective view of a first embodiment of a platform 34 in accordance with the present invention. The platform 34 is gummed or molded on a firm base 36 or frame. The example of the firm base is a rigid material that has a thickness of approximately 0.77 cm. The firm base 36 gives the platform 34 some rigidity for joining purposes. In addition to the base, all components of the platform are made from foam or other suitable elastic materials. The platform 34 includes an interior floor 38 at the bottom, and a wall 40 on its perimeter. The interior of the platform 34 includes two main sections. On the left side of the platform is an embossed loading area 42. The embossed loading area 42 is divided between a series of slits 44., each of which extends from the top of the embossed loading area 42 to the interior floor 38 of the platform 34, in a plurality of fastening elements 46 that are side by side. Each slit 44 leads to a tunnel of the component 48 which has been hollowed between the adjacent fastening elements 46a and 46b and which are shaped to receive an optical component. The figure of each tunnel of the component 48, if desired, can be tailored to have a particular optical component, in profile, for example, square or round, and in length. The access to each tunnel of the component 48 is through the separation of the two fastening elements 46a and 46b in which the tunnel of the component 48 is formed. This causes the slit 44a to be opened between the two fastening elements 46a and 46b , which exposes the tunnel of the component 48. The ends 50 of the fastening elements are rounded, with radii selected to avoid any bending of the optical fiber terminals 12 wound around them. In one of the present embodiments of the invention, it is contemplated that the terminals of the optical fiber may be wound in any direction on the track 56, which is described below, after leaving the tunnel of the component 48. The only exception is that the fiber optic terminals extending from an optical component that is clamped between the first and second fasteners on the left side of the embossed loading area. In order to avoid damage to the fiber terminals, the upper terminal can only be rolled to the right, and the lower terminal can only be rolled to the left, viewed from above.

A series of holes 52 is located in the outer wall of the platform 40. The holes 52 correspond and are in alignment with the tunnels of the component 48 between the fastening elements 46. There is a hole 52 in the end 50 of each fastener 46. Each of the holes 52 is intercepted by an access slit 54 in its upper part extending through the outer wall 40. Once an optical component 10 has been properly seated in a tunnel of the component 48 , the optical fiber terminals 12 extending from the optical component 10 are inserted into a corresponding hole 52 in the outer wall 40 separating the access slit 54 corresponding to the hole 52, whereby the hole 52 is exposed and allows the Fiber optic terminal 12 is replaced in it. This is done to "fix" the terminals of the optical fiber 12 outside and away from the component 10. In addition, the holes 52 can be used to retain the optical fibers for a future splice and prevent them from being pressed or tensioned when the platform is loaded. 34. In the embodiment of the present invention illustrated in Figure 3, the right side of the platform 34 includes a generally rectangular roll guide 58, with a pair of circular inner sections 60. Each circular inner section 60 has an orifice on track 56. In this way, the roll guide 58 has an E shape. The "E" shape of the roll guide 58 minimizes the amount of material employed, while maximizing strength and stability. The corners 62 of the roll guide 58 are rounded, with radii selected to allow bending and to reduce as much as possible the tension in the fiber loop 32 wound around the roll guide 58. Also, as illustrated in Figure 3 , the roll guide 58 terminates one of the fasteners 46, which defines between them a slit through which the optical fiber can pass. This slit provides a "turn" that can be used to change the winding direction of the optical fiber, that is, from right to left or vice versa. The outer perimeters of the roll guide 58 and the embossed loading area 42, the floor of the platform 38 and the inner perimeter of the outer wall 40 define a "track" 56. A track is a closed loop path around the track. which rolls up the excess fiber. Unlike an optical device manufactured by the use of polymer filled with rigid glass, the guide fiber to place a splice and the excess of rolled fiber, the precise tension of the optical fiber wound on track 56 is not decisive for the proper fabrication. There are several notches 64 in the outer wall 40 that surround the track 56. These notches 64 serve to provide access to the fibers from the outside of the module and as a gauge for use in determining the point of two fiber optic terminals. that are going to join. However, as described below, this embodiment of the present invention tolerates a relatively wide variety of location deviation from the measured junction point. In a splice example, the ends of the terminals of the optical fiber 12 are spliced and then protected by a splice sleeve 26. An important issue is that the splice sleeve 26 is in an immediate section of the track 56. In this way a splice can not be made in a corner of the track 56. The outer wall 40 can also include cutting sections 66 to allow the optical fibers to enter the platform 34 for splicing. These cutting sections 66 would be used, for example, to connect separate modules. Although Figure 3 shows the cutting sections located between the fastening elements 46 and the roll guide 56 can be located anywhere on the outer wall 40. Figure 4 shows a perspective view of four retainers 67a-d. These retainers 67a-d fit over track 56 and hold the optical fibers in place. In a modality, the retaining elements 67a-d have a thickness of approximately 0.31 cm, and are made from foam or other elastic material. The retainers 67a-d are held in place on the track 56 by friction. The thicknesses of the retainers 67a-d are determined by the amount of fiber in the track and the depth of the track. Figure 5 illustrates a flow chart of one embodiment of a splice method 68 of the present invention, wherein the platform 34 illustrated in Figure 3 is used. In step 70, each optical component is in a tunnel of the component 48 by dispersing the corresponding slit 44 apart to expose the tunnel of the component 48 between the fastening elements 46. Then the foam is put back around the component. In step 72, the access slits 54 leading to the holes 52 in the outer wall 40 opposite the tunnels 48 are opened, so that the terminals of the optical fiber can be threaded into the holes 52 to "fix" them outside and away from the components. The holes 52 also serve to contain the terminals for a future splice and prevent them from being pressed or tensed when loading the platform. Once all the optical components 10 in the tunnels of the receiving component 48 are suitably secured, and all the terminals of the optical fiber 12 are properly strung through the corresponding holes 52 in the outer wall 40, the terminals of the optical fiber 12 are spliced. In step 74, each pair of pairing optical fiber terminals 12 is released from the hole 52 in the outer wall 40. In step 76 a splice sleeve 26 is placed in one of the two fiber optic terminals 12. In the step 78, each terminal of the optical fiber 12 is wound on track 56 in opposite directions. Before attempting the splice for the first time, the fiber optic terminals 12 are wound around track 56 at least 3 times beyond the point on the track in which they are located, to allow repeated splicing attempts. In step 80, the notches 64 in the outer wall 40 surrounding the track 56 are used to measure the splice point to ensure that it is in the immediate section of the track 56 to accommodate the splice sleeve 26. In step 82 , the terminals of the optical fiber 12, once measured and marked, are unwound from the track 56, and the connection is made in a conventional manner. In step 84, the splice is tested to determine whether the splice operation was successful or not. If the splice fails, then in step 86, the splice is broken and steps 78-86 are repeated until an adequate splice is made. Once the acceptable splice is obtained, the splice sleeve 26 is sealed in place using an acrylate, and the resulting continuous fiber loop 32 is wound on the track 56, in step 88. Steps 72-88 are repeated until in step 90 there are no additional terminals to be spliced. After finishing the splicing operation, then in step 92, the retainers 67a-d are placed on top of the fiber terminals by holding them in place by friction. The use of a platform 34 in accordance with the present invention will be appreciated because instead of having just optical fiber windings and very specific locations for the splices, the optical fiber remains free within a region of the platform. At the actual point where the terminals are spliced do not correspond exactly to the measured splice point, it has no consequences, since the fiber loop 32 compensates for this deviation in the placement around the track 56 by moving closer or farther away from the ends. walls, as needed. This allows assemblers with less experience to work with products with greater complexity and higher volumes. This also eliminates the problem of fiber tension inherent in the deterministic fiber winding. The splicing of the terminals from the elements located outside the platform 34, such as larger optical components, lasers, spiral connector terminals or other optical devices is also made on track 56 of platform 34. The outer terminals enter the track through one of the cutting sections 66, or other orifice 64, on the outer wall 40. After entering the platform 34, the outer terminals are wound on the track 56 and, as described above, the splicing procedure continues. These articles are spliced after mechanically attaching the platform module to the main assembly or strip 24. Figure 6 is a top view of a pair of static platforms 34a, 34b in accordance with one embodiment of the present invention that have been attached to a terminal 24a. The strip 24a in FIG. 6 performs the same electronic and optical functions as the strip 24 in FIGS. 3A and 3B. It will be appreciated that this embodiment of the present invention drastically reduces the number of parts that must be attached to the strip 24A. First of all, there are no Ultem component fasteners or associated physical elements. Second, although some rigid auxiliary fiber guides 22 are still used to provide paths of fiber optic windings 104 from the optical components of the terminal 102 in the static foam platforms, it will be apparent that the terminal strip 24A of FIG. 6 employs many less of these auxiliary guides 22 unlike the terminal 24 in Figures 3A and 3B. Finally, Figure 7 shows an alternative embodiment of the present invention, in which, the track 56 is defined by the outer perimeter of the embossed load area 42. Similar to the embodiment in Figure 3, in the embodiment of the 7, the embossed loading area 42 includes a plurality of fastening elements 46, which are separated by the access slits 44 leading to tunnels of the component 48. The slots 106 in the outer wall 40 have been opened in some way , replacing the holes 52 with access slots 54 of the embodiment illustrated in Figure 3. The cutting sections 66 are provided to receive external terminals and to interconnect separate modules. This smaller version of the invention can be used, for example, where there are relatively few optical components to be spliced or where the space available for assembling and splicing optical components is limited. In addition, the embodiment of Figure 7 includes a return groove 94, which allows changing the direction in which the terminal of the optical fiber 12 is wound on the track 56. It will be apparent to those skilled in the art that various modifications can be made. and variations in the present invention without departing from the spirit and scope thereof. Accordingly, it is intended that this patent encompass the modifications and variations of the invention, as long as they fall within the scope of the appended claims and their equivalents.

Claims (17)

NOVELTY OF THE INVENTION CLAIMS

1. - A platform for receiving optical components comprising: a substrate having a surface; a plurality of fasteners positioned along the surface to hold optical components in a plurality of predetermined positions; and a roll guide projecting upward from the surface adjacent to at least one of said plurality of fasteners, wherein the roll guide and the plurality of fasteners define a path for the winding of optical fibers.

2. The platform according to claim 1, further characterized in that each of the plurality of fasteners is adjacent to at least one of the plurality of fasteners, said adjacent fasteners define between them a cavity for securing the optical components.

3. The platform according to claim 2, further characterized in that the adjacent fasteners also define a passage for access to said cavity.

4. The platform according to claim 1, further characterized in that each of the plurality of fasteners includes rounded ends.

5. - The platform according to claim 1, further characterized in that the roll guide and at least one of the plurality of fasteners define between them a slit for receiving the optical fiber.

6. The platform according to claim 1, further characterized in that the roll guide has a rectangular figure in general.

7. The platform according to claim 6, further characterized in that the roll guide includes radio corners.

8. The platform according to claim 7, further characterized in that the roll guide includes: two interior depressions; and two passages, each one providing access to one of the two inner depressions.

9. The platform according to claim 2, further characterized in that it comprises: a wall extending upwards from said surface, the wall surrounds the plurality of fasteners and the roll guide.

10. The platform according to claim 9, further characterized in that the wall defines a plurality of holes, each of the plurality of holes is positioned to receive an optical fiber attached to one of the optical components.

11. The platform according to claim 10, further characterized in that the wall defines a plurality of holes.

12. - The platform according to claim 1, further characterized in that it is made from foam.

13. The platform according to claim 1, further characterized in that it comprises a rigid substrate attached to the platform.

14. A platform for receiving optical components, comprising: a surface; a plurality of fasteners positioned along the surface to hold the optical components in a plurality of predetermined positions; and a roll guide projecting up from the surface adjacent to at least one of the plurality of fasteners, wherein the roll guide and the plurality of fasteners define a path for the winding of optical fibers; wherein each of the plurality of fasteners is adjacent to at least one of the plurality of fasteners, said adjacent fasteners define between them a cavity for securing the optical components.

15. A method for developing an optical device comprising the steps of: placing a first optical component on a receiving platform, the first optical component having a plurality of optical waveguide fiber-optic terminals; placing a second optical component on the receiving platform, the second optical component having a plurality of fiber optic guide fiber terminals; selecting one of the plurality of optical wave guide fiber terminals of the first optical component; selecting one of the plurality of optical waveguide fiber optic terminals of the second optical component; select a splice point in each of the selected terminals; splice the selected terminals together, the splice occurs at the selected splice points; and store the spliced terminals on the receiving platform.

16. The method according to claim 15, further characterized in that the receiving platform comprises: a surface; a plurality of fasteners positioned along the surface to hold the optical components in a plurality of predetermined positions; and a roll guide projecting up from the surface adjacent to at least one of the plurality of fasteners, wherein the roll guide and the plurality of fasteners define a path for the winding of optical fibers; wherein each of the plurality of fasteners is adjacent to at least one of the plurality of fasteners, the adjacent fasteners define between them a cavity for securing the optical components.

17. The method of compliance with claim 16, further characterized in that the step for selecting a splice point in each of the selected terminals also comprises the steps of: winding the selected terminal of the optical waveguide fiber of the first optical component in one direction along the path, winding the selected terminal of the optical waveguide fiber of the second optical component in the opposite direction along the path; marking each of the selected terminals of the optical waveguide fiber so that a splice made in said marks is in predetermined position on the track.