JP2541011Y2 - Stacked multicore optical fiber connector ferrule - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connector ferrule used in an optical connector for interconnecting optical fibers, and more particularly to a V-groove used for an optical connector for connecting a plurality of optical fibers at once. The present invention relates to a connector ferrule for positioning an optical fiber by using the same.

[0002]

2. Description of the Related Art In an optical cable with a connector, an optical connector is attached to each of a plurality of optical fiber tapes constituting the optical cable. FIG. 6 shows a mechanically transferable (MT) connector which is an example of such an optical connector. One pair of MT connectors 20 ₁ and 20 ₂
Each have a connector ferrule 23 in which each optical fiber 22 is a core wire of the optical fiber ribbon 21 is exposed on the end face in a row, in one MT connector 20 ₁ of the connector ferrule 23, guide pin 24 are provided so as to protrude. The guide pin 24 is connected to the other M
Holes provided in T connector 20 _{and second} connector ferrule 23 adapted to be inserted (not shown), by the guide pin 24, both the MT connector 20 _1, 20
Positioning ₂ is performed. MT connector 20 _1, 20 ₂ of the interconnect, the guide pins 24 by abutting the end face mutual connector ferrule 23 is inserted into the hole to abut, MT connector 20 ₁ of both After that, 2
This is performed by fitting and fixing both with a clip-shaped thing, for example, so that O ₂ does not separate.

[0003] In a cable with a connector using such an optical connector, for example, in the case of a commonly used optical cable with a 1000-fiber connector composed of eight-fiber optical fiber tapes, one end of the optical cable has 125 ( = 1000/8) optical connectors are attached. Therefore, when connecting 1,000 optical fibers with connectors to each other, it is necessary to perform fitting and connection work between the optical connectors 125 times.
If it takes about 2 minutes per fitting / connection,
In order to interconnect the optical cables, it takes 250 minutes (4 hours and 10 minutes) or more just for fitting and connecting the optical connectors. In addition, the work of winding and storing the extra length of 125 optical fiber tapes is also required. Therefore, the actual working time of about 6 hours excluding the preparation time from the working time of a day is 1000 hours. It is difficult to complete the interconnection work of the attached optical cables.

On the other hand, a so-called FTTH (Fiber To The Home) plan for laying optical fibers to homes is being implemented, and the implementation of this plan requires thousands of optical cables. It is thought that it is necessary. If only one optical connector can connect, for example, only about eight optical fibers, it takes an enormous amount of time to connect such thousands of optical fibers with connectors, and to implement the FTTH plan. It is inevitable that the construction of the optical line will be hindered.

[0005] Therefore, an optical connector having a larger number of fibers (several tens of fibers or more) has been proposed. For example, there is a plastic connector ferrule in which 50 to 200 optical fiber insertion holes are two-dimensionally arranged in one plastic connector ferrule to form a 50 to 200 core optical connector ("Plasitic molded singl").
e-mode fifty-fiber connector ", Optical Fiber Commu
nication Conference, 1988). In this case, the plastic connector ferrule is manufactured by injection molding using a mold having a large number of pins corresponding to holes for inserting optical fibers.

[0006]

In the above-described optical connector having 50 to 200 cores using a plastic connector ferrule, the positioning accuracy of the fiber insertion hole in the molding die cannot be sufficiently ensured, and the molding is not possible. It is very difficult to maintain good connection characteristics for all the optical fibers arranged in one optical connector because the pressure at the time causes deformation or bending of the fiber insertion hole. There is a problem that is.

SUMMARY OF THE INVENTION An object of the present invention is to provide a connector ferrule which is used for an optical connector for interconnecting an optical cable with a multi-fiber connector and which enables low-loss connection and shortens the time required for connection between these optical cables. Is to provide.

[0008]

According to the present invention, there is provided a laminated multi-core collective optical fiber connector ferrule of the present invention provided on one surface so as to be parallel to each other, and one end reaching one side of the one surface to position a guide pin. And a V-groove portion provided between the first grooves on the one surface and having a plurality of mutually parallel V-grooves having one end reaching the one side; Two second grooves provided on the other surface corresponding to the one groove for positioning the guide pin, and capable of fitting to the V groove provided on the other surface corresponding to the V groove; A plurality of the substrates are stacked so that each side is on the same plane, using a substrate having a projection having a shape.

[0009]

A V-groove having a plurality of V-grooves is provided on one surface of the substrate, and a projection is provided on the other surface of the substrate so as to fit into the V-groove. Since the first and second grooves for positioning the guide pins are provided on each of the substrates and a plurality of the substrates are laminated, the V grooves and the projections are fitted to each other so that the substrates can be positioned with high precision. When interconnecting an optical connector in which an optical fiber is fixed in a V-groove by using this multi-core multi-fiber optical fiber connector ferrule, the first and second grooves are formed by laminating the substrates. By inserting guide pins into the holes to be formed and positioning the connectors with each other by the guide pins, the positioning between the optical fibers can be accurately performed.

As a material for the substrate, a material having a low linear expansion coefficient is preferably used in order to avoid a decrease in positioning accuracy due to the influence of heat. Here, the material having a low linear expansion coefficient is, for example, silicon, ceramic, glass, or the like, and has a smaller linear expansion coefficient than a commonly used metal (linear expansion coefficient is on the order of 10 ⁻⁶ K ⁻¹ ). Things. Also,
The V-groove may have a recess formed on one surface of the substrate and a V-groove provided on the bottom surface of the recess, and the protrusion may be fitted into the recess.

[0011]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view showing a configuration of a connector ferrule according to an embodiment of the present invention, FIG. 2 is a perspective view of a board used in the connector ferrule of FIG. 1, and FIG. FIG. 4 is a perspective view illustrating the state of lamination of the substrates, and FIG. 5 is a front view illustrating the state of lamination of the substrates in the connector ferrule according to another embodiment of the present invention.

The connector ferrule shown in FIG. 1 is based on the laminated multicore optical fiber connector ferrule of the present invention, and is adapted to a six-core optical fiber tape. And a plastic layer 6 provided so as to bundle a laminate of the substrates 1. In this figure, the optical fiber 7 is already fixed to the optical fiber tape, and the guide pin 8
Is inserted into the guide pin insertion hole 5. Of the end surfaces of the substrates 1 where the V-grooves 2 are exposed, the front end surfaces (shown surfaces) are on the same plane, and the plastic layer 6 is not provided on the end surfaces.

First, the substrate 1 will be described with reference to FIG. The substrate 1 is a substantially rectangular member made of a material having a low linear expansion coefficient such as silicon or ceramic glass. Substrate 1
Are formed with two first grooves 5a so as to be parallel to one of the two opposing sides. The first groove 5a is for positioning the guide pin 8, and is provided so as to extend from one of the two opposing sides to the other. A concave portion 3 is provided between the two first grooves 5a, and six V-grooves 2 are formed on the bottom surface of the concave portion 3.
Are provided in parallel with each other. Each V-groove 2 is also provided so as to extend from one of the two opposite sides to the other. The concave portion 3 and each V-groove 2 constitute a V-groove portion.

In the illustrated lower surface of the substrate 1, two first grooves 5 are provided.
A second groove 5b is provided at a position directly behind each of "a". The protrusion 4 is provided at a position directly behind the recess 3. The shape of the projection 4 fits into the recess 3. In this case, in the fitted state, the projecting portion 4 may enter into the V-groove 2, but a space for inserting an optical fiber to be used does not remain in the V-groove 2. Not be. In this embodiment, the projection 4 comes into contact with the エ ッ ジ -shaped edge between the adjacent V grooves 2.

Next, a method of manufacturing the connector ferrule will be described with reference to FIGS. First, the board | substrate 1 shown in FIG. 2 is laminated | stacked so that the protrusion part 4 may fit in the recessed part 2. FIG. At this time, of the end faces where the V-groove 2 is exposed, the end faces on the front side are aligned on the same plane.
FIG. 3 shows a state in which four substrates 1 are stacked. At this time, the lengths of the substrates 1 in the direction parallel to the V-grooves 2 are set to be different from each other, and as shown in FIG. 4, the lower one of the two overlapping substrates 1 is longer than the upper one. It is good to keep it. By doing so, workability in fixing the optical fiber to the connector ferrule is greatly improved. V-groove 2
The size of the space surrounded by the projection 4 and the projection 4 should be such that the optical fiber to be used can be inserted exactly. The first groove 5a provided on the upper surface of the substrate 1 and the second groove 5b provided on the lower surface of the substrate 1 correspond to each other. A guide pin insertion hole 5 into which the guide pin is inserted is formed by the two grooves 5a and 5b.

Subsequently, the uppermost one and the lowermost one of the stacked substrates 1 are sandwiched between each other, and at least a part of the side surface (the surface where the V-groove 2 is not exposed) of each substrate 1 is sandwiched. Is provided with a plastic layer 6 so as to be covered.
The plastic layer 6 is also for preventing the laminated substrate 1 from shifting. In order to prevent the stacked substrates 1 from being displaced, in addition to providing the plastic layer 5, a method of making a hole so as to penetrate the stacked substrates 1, and a method of fixing with a metal clamp. However, in consideration of ease and reliability of fixing, the method using the plastic layer 6 is preferable.

Next, a method of using the connector ferrule will be described. When four substrates 1 are stacked as shown in FIG. 1, there are three places where the concave portion 3 and the protrusion 4 are fitted. Each of these fitting portions corresponds to an optical fiber tape. V-groove 2
Since there is a space between the optical fiber 7 and the protruding portion 4 in which only the optical fiber 7 can be inserted exactly, the optical fiber 7 which is the core of the optical fiber tape is inserted into the space from the back side in the figure, and an adhesive or the like is applied. Use and fix. In this case, it is preferable that the optical fiber 7 protrudes from the front end surface to some extent. In general, if n V-grooves are cut in one substrate, it corresponds to an n-fiber optical fiber tape.
Since one connection can be made, connection of n-core (m-1) stages becomes possible. That is, if this connector ferrule is used, (m-1) n-core optical fiber tapes can be simultaneously connected, and nx (m-1) -core optical fibers can be connected at a time.

After that, the front end face of the substrate 1 together with the protruding optical fiber 7 is polished so that the front end face is exactly on the same plane, and a cover (not shown) is attached to assemble the optical connector. . The optical connectors assembled in this manner are used as a pair of two optical connectors for connection between optical cables. In this connection, the common guide pin 8 is inserted across the corresponding guide pin insertion hole 5,
In addition, the connector ferrules of the two optical connectors are abutted and joined so that the front end faces of the substrate 1 abut against each other, and the optical connectors are fixed with a clip or the like so as not to be separated from each other. The size of the guide pin 8 is such that it fits exactly into the guide pin insertion hole 5. In this case, the V groove 2 and the guide pin insertion hole 5 of the connector ferrule of the paired optical connector must be mirror images of a plane including the front end face of the substrate 1.

By configuring the laminated multi-core collective optical fiber connector ferrule in this manner, the substrates 1 are accurately positioned relative to each other. For this reason, a configuration in which a plurality of optical fibers 7 are laminated in multiple stages is adopted. Even in this case, displacement of the optical fiber 7 can be prevented, and a stable low-loss connection can be performed. In particular, by using a material having a low coefficient of thermal expansion for the substrate 1, even when performing multi-layer lamination, misalignment between the optical fibers 7 due to a difference in thermal expansion due to uneven temperature is prevented, Stable connection characteristics can be maintained even with temperature changes. Therefore, by using this multi-core multi-fiber optical fiber connector ferrule, it is possible to connect tens to hundreds of optical cables with a pair of optical connectors.

Next, a connector ferrule according to another embodiment of the present invention will be described with reference to FIG. In this connector ferrule, unlike the above-described embodiment, the concave portion 3 is not provided in the substrate 1 '. Instead, a projection 4 ′ on the lower surface of the substrate 1 ′ is provided with linear irregularities corresponding to the V-groove 2. Therefore, when the substrates 1 ′ are stacked, the projections 4 ′ penetrate into the V-groove 2. That is, the V-groove 2 and the projection 4 are directly fitted. Even in this case, a space in which the optical fiber 7 is to be inserted is secured between the surface of the V-groove 2 and the surface of the protrusion 4. The method of manufacturing and using this connector ferrule is the same as that of the above-described embodiment.

[0021]

As described above, according to the present invention, a V-groove having a plurality of V-grooves is provided on one surface of a substrate, and a protruding portion which fits into the V-groove is provided on the other surface of the substrate. First and second grooves for positioning guide pins are provided on both surfaces of the substrate so as to correspond to each other, and by stacking a plurality of substrates, positioning between the optical fibers is accurately performed. Therefore, there is an effect that a connector ferrule that can be connected with low loss and that can reduce the time required for connection between multi-core optical cables can be obtained.

[Brief description of the drawings]

FIG. 1 is a front view showing a configuration of a connector ferrule according to one embodiment of the present invention.

FIG. 2 is a perspective view of a board used in the connector ferrule of FIG. 1;

FIG. 3 is a front view illustrating a laminated state of substrates.

FIG. 4 is a perspective view illustrating a laminated state of substrates.

FIG. 5 is a front view showing a state in which boards are stacked in a connector ferrule according to another embodiment of the present invention.

FIG. 6 is a perspective view showing a structure of an MT connector which is an example of a conventional optical connector.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1 'board 2 V groove 3 recess 4, 4' protrusion 5 guide pin insertion hole 5a first groove 5b second groove 6 plastic layer 7 optical fiber 8 guide pin

Claims (3)

(57) [Scope of request for utility model registration] 1. A connector ferrule which is used for an optical connector for connecting a plurality of optical fibers collectively and which positions an optical fiber by a V-groove, provided on one surface so as to be parallel to each other. One end reaches one side of the one surface to position the guide pin 2
A plurality of parallel V-shaped grooves provided between the first groove of the book and the first groove of the one surface and having one end reaching the one side.
A V groove having a groove, two second grooves provided on the other surface corresponding to the first groove for positioning the guide pin, and provided on the other surface corresponding to the V groove; A plurality of the substrates are laminated such that the sides are respectively on the same plane, using a substrate having a projection that can be fitted into the V-groove portion. Optical fiber connector ferrule. 2. The multi-fiber multilayer optical fiber connector ferrule according to claim 1, wherein the substrate is made of a material having a low coefficient of linear expansion. 3. The substrate according to claim 1, wherein the V-groove portion has a concave portion formed on one surface of the substrate, and a V-groove is provided on the bottom surface of the concave portion, and the projecting portion is fitted into the concave portion. 2. The multi-core collective optical fiber connector ferrule described in 1. above.