JP2007233144A - Multi-mold optical fiber and optical interconnection method and optical circuit device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-mold optical fiber which is bendable laterally and thereby provides the high degree of freedom of an optical interconnection in the optical interconnection or the like in optical equipment or on an optical circuit substrate. <P>SOLUTION: The multi-mold optical fiber 1 has a structure in which a plurality of optical fibers 2 are wired in a desired wiring pattern and the whole wiring pattern is molded with resin. The cross section of the mold resin 3 of the multi-mold optical fiber 1 is made into, for example, a non-flat rectangular cross section, for example, a square or the like, thus such a problem that the bending in width direction is impossible is solved, unlike an optical fiber ribbon or an optical fiber sheet, and the freedom of bending is enhanced. Thus, the freedom of the optical interconnection is enhanced and the optical interconnection is made easier in the optical interconnection in the optical equipment or the optical interconnection on the optical circuit substrate. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a multi-core molded optical fiber used when optical wiring is integrated with a plurality of optical fibers, an optical wiring method using the same, and an optical circuit device.

When optically wiring a plurality of optical fibers along the surface of an optical substrate in an optical device or on an optical circuit board, a method for optical wiring by drawing each optical fiber individually is naturally performed. In many cases, the optical fiber is integrated and optical wiring is performed using a flexible substrate (circuit) with an optical connector on which an optical wiring pattern of the optical fiber is formed. The configuration of the flexible substrate is generally one in which a plurality of optical fibers are arranged on a base material (bottom plate) and a resin coating such as polyimide is overlaid. Furthermore, there is a wiring board using a film that is more flexible than polyimide (Patent Document 1 and others).
Patent 2574611

The flexible substrate is thin and generally wide, so it is easy to bend in the thin direction, that is, in the thickness direction, but as the number of optical fibers increases, the optical fibers are not twisted in the width direction. It may be difficult to bend, and the degree of freedom of bending is low. That is, the degree of freedom of optical wiring is low.
Therefore, when the optical connector is attached to the protruding end of the flexible substrate, when the optical connector is positioned and connected to an optoelectronic element such as a bicell on the optical circuit board side, the optical axis direction of the photoelectric element and the connection of the optical connector Although it is necessary to match the direction, when it is necessary to bend the flexible substrate in the width direction due to the layout, it is necessary to bend the projecting end portion.
In an optical connector using a positioning member such as a fitting pin, the optical fiber is twisted because the fitting pin is mechanically pushed in and fixed at a position where the optical axis of the photoelectric element and its own optical axis match. In addition, the connecting direction of the optical connector attached to the tip of the optical connector is applied with a twisting force different from the initial direction, and as a result, there is a problem that it is difficult to connect to the optoelectronic device. For this reason, when there is a design change in the pattern of the optical circuit board, it is difficult to cope with the change in the optical connector connection position on the flexible board side. This problem became greater as flexible substrates became multi-core and wide.
That is, since the wiring pattern is fixed, there is a problem that it cannot cope with a design change of the substrate circuit.
As a countermeasure, it is conceivable to use a wiring member such as an optical fiber cord that has a round cross section and is relatively flexible in an arbitrary direction. However, in order to use on an optical circuit board, the displacement in the width direction needs to be small like a flexible board. If there is a high degree of freedom in the movement in the width direction, there is a risk of causing communication failure due to contact with circuit components on the optical circuit board, so it is necessary to fix the optical circuit board in some places. Providing means for mechanical fixing is not preferable in design. Further, a multi-core optical fiber cord separated by a single core and attached with optical connectors at both ends can be used for optical wiring. However, for the same reason, it cannot be used as it is for wiring on an optical circuit board.

  The present invention was made to eliminate the above-mentioned conventional drawbacks, and is suitable for use in a case where a plurality of optical fibers are integrated and optically wired on an optical circuit board. Multi-core molded optical fiber that has good flexibility not only in the vertical direction but also along the surface direction of the optical circuit board and that can maintain its own wiring shape, and an optical wiring method using the same, and an optical circuit An object is to provide an apparatus.

The multi-core molded optical fiber of the invention of claim 1 that solves the above problems is
A plurality of optical fibers are wired with a desired wiring pattern, and the entire wiring pattern is resin-molded.

  A second aspect of the present invention provides the multi-core molded optical fiber according to the first aspect, wherein an optical connector is attached to the optical fiber and resin-molded with the optical connector so that the optical fiber insertion port of the optical connector is also filled with the resin. Thus, a boot portion for protecting the optical connector mouth portion of the optical fiber is formed.

  According to a third aspect of the present invention, in the multi-core molded optical fiber according to the first or second aspect, the other end of the optical fiber bundle having the multi-fiber optical connector attached to one end is branched, and the optical connector is attached to the tip of the branched optical fiber. The optical fiber bundle and the branch optical fiber are both resin-molded.

  According to a fourth aspect of the present invention, in the multi-core molded optical fiber according to any one of the first to third aspects, the cross-sectional shape of the mold resin of the optical fiber is a non-flat rectangular cross-sectional shape, It is characterized by being bendable.

  According to a fifth aspect of the present invention, there is provided an optical wiring method in which the multi-core molded optical fiber according to any one of the first to fourth aspects is disposed on an optical circuit board, the multi-fiber optical connector is an end side of the optical circuit board, Optical wiring is performed with the optical connector inside the substrate.

  An optical circuit device according to a sixth aspect of the invention includes the multi-core molded optical fiber according to any one of the first to fifth aspects disposed on an optical circuit board, the multi-fiber optical connector as an end side of the optical circuit board, and the branch optical fiber side. The optical wiring is provided with the optical connector inside the substrate.

The multi-core molded optical fiber of the present invention is wired with a desired wiring pattern obtained by bending a plurality of optical fibers, resin-molded as a whole, and having a vertical to horizontal dimension ratio that can be bent in both vertical and horizontal directions. For example, by using a rectangular cross-section, the problem of being unable to bend in the width direction without changing the directionality of the optical connector attached to the tip is eliminated because twisting occurs unlike a flexible substrate, and the degree of freedom in bending is high. Become. This may be bendable to the same extent in the present invention.
Therefore, for example, when an optical connector is attached to this multi-core molded optical fiber, and the optical connector is connected to an optoelectronic device on the optical circuit board side, the multi-core single fiber is formed as a portion corresponding to the protruding end of the flexible board. Since the optical fiber is branched at the core and the optical connector is attached to the tip of the optical fiber, the degree of freedom of wiring is maintained even when a plurality of optical circuit elements are mounted on the optical circuit board.
In addition, even if the layout on the optical circuit board side is slightly changed, there is no problem that the multi-core molded optical fiber needs to be bent so that the optical connector can be easily connected to the optoelectronic device.
For this reason, it is possible to easily cope with the design change of the pattern of the optical circuit board on the multi-fiber mold optical fiber side of the present invention.
From the above, the optical wiring in the optical device, or the optical wiring on the optical circuit board or in the optical circuit device becomes easy.

  According to the second aspect of the present invention, since the boot portion is formed at the optical fiber insertion portion at the same time when the plurality of optical fibers are integrated with the resin, it is separately provided to protect the optical connector mouth portion of the optical fiber. No part boots are required, and the cost of optical wiring can be reduced.

  Hereinafter, a multi-core molded optical fiber, an optical wiring method, and an optical circuit device embodying the present invention will be described with reference to the drawings.

  1A is a perspective view of a multi-core molded optical fiber 1 according to an embodiment of the present invention, and FIG. 1B is a diagram showing a bent state of an optical fiber 2 in the multi-core molded optical fiber 1. FIG. 2 is a cross-sectional view of the multi-core molded optical fiber 1. The molded optical fiber 1 is, for example, one in which four optical fibers 2 are wired with a desired wiring pattern bent in a mold, and a resin mold is poured into the resin. The molded resin is indicated by 3. Silicone rubber or the like can be used as the resin, but the resin is not limited to this and may be any resin that is flexible to some extent.

FIG. 3 shows a lower mold 4 among molds for resin-molding the multi-core molded optical fiber 1. The mold 4 includes a bent groove 5 corresponding to a desired wiring pattern. Although not shown, the upper mold may be simply a flat mold that forms the ceiling surface of the groove 5.
When the multi-core molded optical fiber 1 is resin-molded using this mold 4, for example, as shown in FIGS. 4 and 5, a spacer 6 that holds the optical fiber 2 at a predetermined height may be used. The illustrated spacer 6 has a plate shape having a holding groove 6 a that sandwiches the optical fiber 2. With the spacer 6 attached to the optical fiber 2 as shown in the figure, the optical fiber 2 is wired in the groove 5 of the mold 4, covered with a flat upper mold, covered, and resin is injected into the groove 5. Then, a multi-core molded optical fiber 1 in which a plurality of optical fibers 2 are molded with a resin 3 as shown in FIGS. 1 and 2 is obtained. In this case, the spacer 6 remains embedded in the resin 3, but it is preferable to use the same material as the resin 3 as the material of the spacer 6.

The cross-sectional shape of the multi-core molded optical fiber 1 of this embodiment is substantially square. Therefore, the multi-fiber mold optical fiber 1 is mounted in the left-right direction (mounted on the optical circuit board) in which the optical fibers 2 are arranged in the cross-sectional view of FIG. In some cases, it can be bent with the same ease of bending whether it is bent in the direction of the substrate surface) or in the vertical direction perpendicular to this (when mounted on the optical circuit board, the direction perpendicular to the substrate). it can.
Therefore, as a conventional flexible substrate or a similar one, unlike the wide optical fiber tape and the optical fiber sheet, the problem that the bending flexibility in the width direction is small is solved, and the bending flexibility is increased. Therefore, for example, when an optical connector is attached to the multi-fiber optical fiber 1 as will be described later, and the optical connector is connected to an optoelectronic element on the optical circuit board side, what is the layout on the optical circuit board side? Even if it is a thing, the problem which must be bent so that the said multi-core mold optical fiber 1 may be twisted does not arise, but the connection to the optoelectronic device of an optical connector becomes easy.
For this reason, it becomes possible to easily cope with the design change of the pattern of the optical circuit board on the multi-core molded optical fiber 1 side of the present invention.
From the above, the optical wiring in the optical device, the optical wiring on the optical circuit board, or the optical circuit device is facilitated.

FIG. 6 shows another embodiment of the present invention, and is a perspective view of a mold 14 used for resin molding of a multi-core molded optical fiber. This mold 14 is formed by reducing the depth of the groove 15 for accommodating the optical fiber 2.
In this case, for example, as shown in FIG. 7 (a), a simple linear spacer 16 is arranged on the bottom surface of the groove 15, and the optical fiber 2 is wired thereon, and in this state, an upper mold (not shown) is mounted. Covering and covering and injecting the resin into the groove 15, as shown in FIG. 7 (b), a multi-fiber optical fiber 11 is obtained in which the optical fiber 2 is close to one side of the resin 3 having a rectangular cross section. It is done. In this case, the linear spacer 16 remains embedded.

  In the multi-core molded optical fiber 11 of this embodiment, the vertical dimension of the mold resin 3 is about half that of the horizontal dimension as compared with that of FIG. 2, but it is still in the case of an optical fiber tape or an optical fiber sheet. In comparison, bending in the lateral direction (width direction) is much easier.

FIG. 8 shows still another embodiment of the present invention. In this embodiment, the mold 14 shown in FIG. 6 is used in the same manner as described above. However, the optical fiber 2 is placed directly on the bottom surface of the groove 15 and is resin-molded. A multi-core molded optical fiber is indicated at 21.
In this case, as shown in FIG. 8 (B), the optical fiber 2 is embedded in the resin 3 in such a manner that it is partially exposed on one side surface.

As a method for obtaining a multi-core molded optical fiber in which the optical fiber 2 is embedded in the central portion with a substantially square cross section like the multi-core molded optical fiber 1 of FIG. 2 without using a spacer, the methods shown in FIGS. Is possible.
FIG. 9A is a cross-sectional view of the groove 15 portion of the lower mold 14 used in the first step, which is the same as the mold 14 of FIG. First, resin molding as shown in the embodiment of FIG. 8 is performed using the mold 14 and the optical fiber 2 is embedded in the resin 3 in a manner that is partially exposed on one side surface, as shown in FIG. A resin molded product 1a ′ is obtained on the way. The bent shape of the resin molded product 1a ′ is the same as that of the multi-core molded optical fiber 1 shown in FIG.
In the next step, a mold 24 having a groove 25 shown in FIG. The bending pattern of the groove 25 of the mold 24 is a bent shape in which the resin molded product 1a ′ is turned backward (upside down), and the depth of the groove 25 is about 2 of the depth of the groove 15 in FIG. Is double.
A resin molded product 1 a ′ that has been previously resin-molded in the groove 25 of the mold 24 is accommodated as shown in FIG. Next, when a flat upper mold is placed on the lid and the resin is poured into the groove 25, the optical fiber 2 is embedded in the center of the mold resin 3 having a substantially square cross section as shown in FIG. A molded optical fiber 1 ′ (generally the same as that shown in FIG. 2) is obtained.

  11 to 13 show another embodiment of the present invention. In this embodiment, an optical connector is attached to an optical fiber and resin-molded with the optical connector so that the resin is filled in the optical fiber insertion port 36a of the optical connector 36 as shown in FIG. The boot portion 3a for protecting the optical connector mouth portion of the optical fiber is formed.

In this case, as shown in FIG. 12, in the illustrated example, four optical fibers 2 are attached to an optical connector (ferrule) 36 in advance. The optical connector 31 is, for example, a so-called MT connector, and the bare fiber 2a from which the coating has been removed is inserted into the optical fiber hole 36b, and the adhesive 33 is filled from the adhesive filling window 36c to be bonded and fixed. In this case, as shown in FIG. 12B, the optical fiber insertion port 36a is not filled with an adhesive.
Moreover, as a metal mold | die, the metal mold | die 34 which has the recess 34a which accommodates an optical connector is used like FIG. 13 which showed the part. The optical connector 36 to which the optical fiber 2 is previously attached is accommodated in the recess 34a for accommodating the optical connector of the mold 34, the optical fiber 2 is disposed in the groove 35, and the lid is covered with the upper mold in this state. When the resin is injected into the groove 35, as shown in FIG. 11, a multi-core molded optical fiber 31 with an optical connector having a boot portion 3a for protecting the optical connector mouth portion of the optical fiber 2 is obtained.

  According to this multi-core molded optical fiber 31 with an optical connector, a separate boot is not required for protecting the optical connector opening portion of the optical fiber, and the cost of the optical wiring can be reduced.

  FIG. 14 shows a multi-core molded optical fiber 41 with an optical connector according to another embodiment of the present invention. This multi-fiber optical fiber 41 with an optical connector is applied in the case of a wiring pattern for branching an optical fiber bundle, and the other end of the optical fiber bundle having a multi-fiber optical connector 46 attached to one end is branched. The optical connectors 47, 48, and 49 are attached to the ends of the branched optical fibers, and the optical fiber bundle and the branched optical fibers are both resin-molded. , 48 and 49, a boot portion 3a is formed in the optical fiber insertion port portion as in FIG.

FIG. 15 schematically shows an embodiment in which the multi-fiber optical fiber 41 with optical connectors is wired on the optical circuit board 50. In this figure, an optical circuit board 50 is mounted with optoelectronic elements 52, 53, 54, etc., and on the optical circuit board 50, a multi-core molded optical fiber 41 with an optical connector is connected to optical connectors 47, 48, 49 is connected to the optoelectronic elements 52, 53, and 54 to constitute an optical circuit device 51. In the illustrated example, the multi-fiber optical connector 46 on one end side is fixed to the edge of the optical circuit board 50, and an optical connector (not shown) is connected.
In this case, since the multi-core molded optical fiber 41 can be easily bent not only in the direction perpendicular to the substrate surface but also in the direction parallel to the substrate surface, the component arrangement on the optical circuit board 50 can be routed around. Thus, it is possible to easily cope with a design change of the pattern of the optical circuit board 50.

  FIG. 16 shows a mold 44 for manufacturing the multi-core molded optical fiber 41 with the optical connector. The pattern of the groove 45 of the mold 44 has a bent shape that matches the bending mode of the multi-core molded optical fiber 41 to be manufactured. The mold 44 has recesses 44a, 44b, 44c, and 44d for receiving optical connectors similar to the recesses 34a for receiving optical connectors in FIG. In the same manner as described above, the optical connectors 46, 47, 48, and 49 are accommodated in the recesses 44 a, 44 b, 44 c, and 44 d for accommodating the optical connectors of the mold 44, respectively. In this state, when the resin is poured into the groove 45 by covering with an upper mold, the multi-fiber optical fiber 41 with an optical connector shown in FIG. 14 is obtained.

1 shows an embodiment of a multi-core molded optical fiber according to an embodiment of the present invention, in which (a) is a perspective view of the multi-core molded optical fiber, and (b) is a bend of the optical fiber in the multi-core molded optical fiber. It is the figure which showed the state. It is sectional drawing of the multi-core mold optical fiber of FIG. It is a perspective view of the metal mold | die used for resin molding of the said multi-core mold optical fiber. It is a perspective view of the spacer used when performing resin molding with the metal mold | die of FIG. It is a longitudinal cross-sectional view of the principal part at the time of resin molding of the said metal mold | die. FIG. 7 is a perspective view (a diagram corresponding to FIG. 3) of a mold used for resin molding of a multi-core molded optical fiber, showing another embodiment. (A) shows one mode of resin molding by the mold of FIG. 6, and is a longitudinal sectional view of the main part of the mold, and (b) is a sectional view of a multi-core molded optical fiber obtained by resin molding. (A) shows the other aspect of the resin molding by the metal mold | die of FIG. 6, and is a longitudinal cross-sectional view of the principal part of a metal mold | die, (b) is sectional drawing of the multi-core mold optical fiber obtained by resin molding. . FIG. 3 shows another embodiment of resin molding for obtaining the multi-core molded optical fiber having the cross-sectional shape of FIG. 2, wherein (a) is a cross-sectional view of a groove portion of a mold used in the first step of resin molding; ) Is a cross-sectional view of an intermediate resin molded product obtained in the first resin molding step. (A) is sectional drawing of the groove part of the metal mold | die used for the final resin molding process following FIG. 9, (b) is sectional drawing of the multi-core mold optical fiber obtained by the final resin molding process. The other Example of this invention is shown and it is sectional drawing of the optical connector part in the multi-core mold optical fiber with an optical connector. FIGS. 11A and 11B illustrate a process for obtaining a multi-core molded optical fiber with an optical connector in FIG. 11, where FIG. 11A is a perspective view of an optical connector portion attached to the optical fiber, and FIG. It is a perspective view which shows the connector accommodating part of the metal mold | die for resin-molding the multi-core mold optical fiber with an optical connector of FIG. The perspective view which shows the other Example of this invention, and shows the multi-core mold optical fiber with an optical connector which branched the other end side of the optical fiber bundle with which the multi-fiber optical connector was attached to one end side, and was attached to the optical connector It is. It is a typical top view of the optical circuit board of one Example optically wired using the multi-core mold optical fiber with an optical connector of FIG. It is a perspective view of the metal mold | die which obtains the multi-core mold optical fiber with an optical connector of FIG.

Explanation of symbols

1, 1 ', 11, 31 Multi-core molded optical fiber 1a' Resin molded product 2 Optical fiber 2a Bare fiber 3 Mold resin 3a Boot parts 4, 14, 34, 44 Mold (lower mold)
34a Recesses 5, 15, 25, 35, 45 Grooves 6, 16 Spacers 31, 41 Multi-fiber molded optical fiber 33 with optical connector Adhesive 36 Optical connector 36a Optical fiber insertion port 36b Optical fiber hole 36c Adhesion Agent filling window 46 Multi-fiber optical connectors 47, 48, 49 (on one end side) Optical connector 50 (on branch side) Optical circuit board 51 Optical circuit device 52, 53, 54 Optoelectronic device

Claims (6)

  A multi-fiber optical fiber characterized in that a plurality of optical fibers are wired with a desired wiring pattern, and the entire wiring pattern is resin-molded.   By attaching an optical connector to the optical fiber and resin molding with the optical connector attached, the optical fiber insertion port of the optical connector is also filled with resin, and the boot portion for protecting the optical connector port portion of the optical fiber The multi-core molded optical fiber according to claim 1, wherein:   The other end of the optical fiber bundle having a multi-fiber optical connector attached to one end is branched, an optical connector is attached to the tip of the branched optical fiber, and both the optical fiber bundle and the branched optical fiber are resin-molded. The multi-core molded optical fiber according to claim 1 or 2, wherein   The cross-sectional shape of the mold resin of the optical fiber is a non-flat rectangular cross-sectional shape, and the vertical / horizontal dimension ratio of the rectangular cross-sectional shape can be bent to the same extent in both the vertical and horizontal directions. The multi-core molded optical fiber described.   The multi-core molded optical fiber according to claim 1 is arranged on an optical circuit board, the multi-fiber optical connector is set to the end side of the optical circuit board, and the optical connector on the branch optical fiber side is set to the inside of the board to perform optical wiring. An optical wiring method.   The multi-core molded optical fiber according to claim 1 is disposed on an optical circuit board, the multi-fiber optical connector is set to the end side of the optical circuit board, and the optical connector on the branch optical fiber side is set to the inside of the board to perform optical wiring. An optical circuit device characterized by that.

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