JP2519748B2 - Optical connector ferrule - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an optical connector ferrule for positioning and holding optical fibers to realize coupling in optical communication.

(Prior Art) FIG. 4 is a vertical cross-sectional view of a typical conventional single-fiber optical connector ferrule. An optical fiber guide hole (51) and an optical fiber core wire guide hole (52) communicating with the optical fiber guide hole (51) are provided at the center with respect to the resin-molded (53) outer diameter of the optical fiber core wire and the optical fiber core wire. A bare optical fiber from which the coating at the tip of the optical fiber core has been removed is inserted, an adhesive is fixed, and then the end face of the tip is polished to obtain a smooth end face. The above-mentioned end face polishing includes rough polishing, medium polishing, and final polishing.
~ 4 steps are required, and in particular, in order to achieve stable optical contact by directly contacting naked optical fibers with each other to reduce coupling loss, it is necessary to polish the tip into a curved surface, which requires high precision. A special polishing machine was needed.

FIG. 5 is an external view of a conventional multi-fiber optical connector ferrule. As shown in the drawing, a plurality of optical fiber guide holes (56) are formed on the center line connecting the two guide pin holes (57) and the guide pin holes (57) inside the resin-molded ferrule body (55). The optical fiber is inserted here, fixed with an adhesive, and the end face is polished.

(Problems to be solved) As described above, in the conventional single-core optical connector ferrule and multi-core optical connector ferrule, the optical fiber is inserted into the optical fiber guide hole, fixed with the adhesive, and the end face is polished. The process is established. When attempting to install the optical connector ferrule on-site in these processes, especially in the polishing process, a dedicated polishing machine, polishing machine,
Since a large number of devices such as a polishing sheet are required, there is a problem that it is difficult to carry out the on-site installation work.

Further, water or a solution is usually required for the polishing step, and it is necessary to replenish it, which has been an obstacle to the on-site installation.

On the other hand, a short work time is required for on-site installation, but it takes 5 to 10 minutes for the polishing process, and 15 to 30 minutes for the entire installation process in the case of multi-core installation. Was there.

(Means for Solving the Problems) The present invention provides an optical connector ferrule that solves the above problems, and is characterized by a tip guide in which a pre-optical fiber is previously positioned and held and its tip is polished. The optical fiber guide member comprises a member and a guide member main body having an optical fiber guide hole communicating with the pre-optical fiber therein, and an end face of the guide member main body being in contact in the axial direction.

FIG. 1 is an explanatory view of a specific example of an optical connector ferrule of the present invention. FIG. 1A is a longitudinal sectional view, and FIG. 1B is a left end view of the tip guide member of FIG.

In the drawing, (1) is an optical fiber guide member, which is composed of a guide member main body (2) and a tip end guide member (3). The guide member main body (2) has a guide groove substrate (6) having an optical fiber guide groove (4) and an optical fiber core wire guide groove (5) communicating with the guide groove substrate (6) formed on the upper surface thereof.
The flat plate (7) is joined to form an optical fiber guide hole (4 ') and an optical fiber core wire guide hole (5') communicating therewith.

The tip end guide member (3) is formed by joining a flat plate (11) on a guide groove substrate (10) having an optical fiber guide groove (8) and a guide pin groove (9) formed on the upper surface,
A pre-optical fiber (12) is previously positioned and fixed by an adhesive in the optical fiber guide hole (8 ') formed by this, and is in contact with the tip end face (14) and the guide member main body (2). The rear end face (15) is polished.

The tip end guide member (3) and the guide member main body (2) are positioned and connected by communicating the optical fiber guide groove (8) in which the pre-optical fiber (12) is positioned and the optical fiber guide groove (4). ing.

As described above, the optical fiber guide member (1) in which the guide member body (2) and the distal end guide member (3) in which the pre-optical fiber (12) is positioned and fixed in advance are connected are concentric with the outside thereof. Resin molding (17) is performed together with the arranged metal pipe (16) to form an optical connector ferrule as shown in FIG.

According to such an optical connector ferrule, an optical fiber is inserted into the optical fiber guide hole (4) in the guide member main body (2) at the site, and the end face guide member (3) whose end face is preliminarily polished. By fixing the pre-optical fiber (12) with a butt adhesive, the conventional polishing step becomes unnecessary. As a result, not only the polishing device is unnecessary, but also the installation time is shortened and the work is facilitated. In summary, the basic principle of the optical connector ferrule of the present invention is that, if a pre-optical fiber is positioned and fixed in advance in the factory and an optical connector ferrule provided with a tip guide member whose end face is polished is prepared, it can be used locally. An optical connector can be easily realized by inserting an optical fiber into the main body of the guide member and fixing it by adhesion.

Furthermore, in the optical connector ferrule of the present invention, the optical fiber guide hole (4 ') and the optical fiber core wire guide hole (5') of the guide member main body (2) are made to facilitate the realization of the optical connector on site. A UV-curable adhesive that has the function of a refractive index matching agent is injected in advance, and an optical fiber is inserted at the site and irradiated with ultraviolet rays to combine the optical fiber with the pre-optical fiber (12). Fixing can be easily realized.

In the specific example shown in FIG. 1, if the outer peripheral portion of the tip end guide member (3) is processed with the groove (18), it is possible to prevent it from coming off from the molded resin portion (17).

FIG. 2 is an explanatory view of a specific example of the multi-fiber optical connector ferrule of the present invention, in which FIG. 2A is a vertical sectional view and FIG. 2B is a left sectional view of FIG.

As shown in the drawing, the optical fiber guide member (20) that constitutes the optical connector ferrule includes a distal end guide member (2
2) and the guide member main body (21) are connected and fixed to each other. The tip end guide member (22) has a flat plate (27) on a guide groove substrate (25) having a plurality of optical fiber guide grooves (29) and two guide pin grooves (30) formed on the upper surface.
The pre-optical fibers (27) are positioned and fixed by an adhesive in a plurality of optical fiber guide holes (29) formed by joining the guide pin holes (30 ').
A guide pin (31) for realizing the connection is inserted in and the end face (33) is ground in advance in a factory or the like. Further, the guide member main body (21) has a guide groove substrate (2 having a plurality of fiber guide grooves (32) formed on the upper surface.
3) It is formed by joining a flat plate (24) on top. In this case, the guide groove substrate (23) is longer than the flat plate (24), and when the end faces are joined and joined, part of the optical fiber guide groove (32) on the guide groove substrate (23) is exposed, and This facilitates insertion of the fiber (B) into the guide hole (32 '). Further, a step portion (28) is formed at the rear end of the guide groove substrate (23), and the optical fiber core wire (A) is fixed to this portion. Further, an ultraviolet curable adhesive (29) having a refractive index matching agent function is preliminarily injected into the optical fiber guide hole (32 '), and the pre optical fiber (27 ) And the optical fiber (B) can be easily fixed.

FIG. 3 is an explanatory view of another specific example of the multi-fiber optical connector ferrule of the present invention, in which FIG. 3 (a) is a longitudinal sectional view and FIG. 3 (b).
[Fig. 3] is a left end view of Fig.

As shown in the drawings, the tip guide member (42) and the guide member main body (41) of the optical fiber guide member (1) constituting the optical connector ferrule in this specific example are not of the completely separate type as shown in FIG. , The optical fiber section is divided. That is, the guide groove substrate (43) having the optical fiber guide groove (49) formed on the upper surface is an integral product, and the groove (48) deeper than the groove is formed in the direction perpendicular to the optical fiber guide groove (49). ing. Then, the flat plate (44) is joined to the tip (left side in the figure) from the recess (48), and the pre-optical fiber (47) is previously positioned and fixed by the adhesive in the optical fiber guide hole (49 ') inside the flat plate (44). Has been done,
It constitutes a tip end guide member (42). As described above, the tip end face of the tip guide member (42) is previously polished in a factory or the like. A flat plate (45) is joined behind the recess (48) of the guide groove substrate (43) to form a guide member body (41). The guide groove substrate (43) and flat plate (4
As for the relationship of the length of 5), the guide groove substrate (43) is longer than the flat plate (45) as in the specific example of FIG. 2 and one of the optical fiber guide grooves (49) on the guide groove substrate (43) is The part is exposed and the guide member body (41) for the optical fiber (B)
It is easy to insert inside. Further, a step portion (46) is formed at the rear end of the guide groove substrate (43), and the optical fiber core wire (A) is fixed to this portion. Further, the optical fiber guide groove (49) is An ultraviolet-curing adhesive (50) having a refractive index matching agent function has been injected in advance,
By irradiating ultraviolet rays on site, it is possible to easily realize the coupling and fixing of the pre-optical fiber (47) and the optical fiber (B).

(Operation) According to the optical connector ferrule of the present invention as described above, the adhesive fixing of the optical fiber, which conventionally took 5 minutes and generally 30 minutes by the high-speed adhesive, is completed in only about 30 seconds. The attachment of the optical connector to the optical connector ferrule is completed in about 1 minute even if all are included from the end treatment of the optical fiber.

After that, although the optical connector ferrule and its housing are assembled, the process is completed in a few minutes, so that it can be mounted with a sufficient margin in a total of 5 minutes. In particular, when attaching an optical connector to the optical fiber core, the housing is made of a material that is transparent to ultraviolet light in advance, and the optical fiber is simply inserted from the rear of the assembled optical connector plug, and the May be irradiated to couple with the pre-optical fiber. By using such a method, all steps are completed in about 1 minute, so that it can be dramatically shortened compared to the conventional 15 to 30 minutes.

Further, the technical idea of the present invention is to reduce the work at the site as much as possible. On the contrary, since the work at the site is greatly simplified, it is easy to automate, and if it is automated based on such a technology, it will take 30 seconds. / It will be easy to put the local high-speed automatic mounting device into practical use at the tact time of the optical connector.

(Example) An optical fiber guide member as shown in FIG. 1 was formed by joining a silicon guide groove substrate and a flat plate. The length of the tip guide member is about 6 mm, and the guide pin is
0.35mmφ was used. A pre-optical fiber was previously inserted and fixed in the tip end guide member, the end surface of the guide member body side was polished, and the end surface of the tip end side was left untreated for peripheral grinding.

After such a tip end guide member was joined to the guide member main body, it was insert-molded together with the outer peripheral metal pipe in the mold. After molding, remove the guide pin, grind the outer periphery to the center of the hole to improve the eccentricity, and then grind the end face of the tip end guide member into a spherical shape, and then use the optical connector ferrule as shown in Fig. 1 (a). Got

An optical fiber was inserted and fixed in the guide member main body of the optical connector ferrule thus obtained, and the optical fibers were joined together and the total coupling loss was measured. As a result of testing using a single mode fiber, the average coupling loss is about 0.6 dB, about 0.3 dB between the optical connectors, and about 0.15 dB between the tip guide member inside the optical connector ferrule and the guide member main body. I understand. The conventional split sleeve and push-on type housing were used to connect this optical connector.

An ultraviolet curing adhesive with a refractive index matching agent function was used to fix the optical fiber, but the curing time is about 30 seconds, and it should be completed within 100 seconds to assemble one optical connector. It was confirmed.

Furthermore, the temperature characteristics of such an optical connector coupling were also examined, and it was found that the fluctuation range was within 0.2 dB at -40 ° C to + 80 ° C, which was a value that was not a problem for practical use.

(Effects of the Invention) As described above, according to the optical connector ferrule of the present invention, it is formed by the tip end guide member that preliminarily positions and holds the pre-optical fiber and the guide member main body that follows the front end guide member. Since it is only necessary to insert the optical fiber into the member main body and connect it to the pre-optical fiber, not only the polishing machine for the end face polishing that was conventionally required in the field is not required, but also the optical connector in the field can be used. Installation work has become extremely easy and can be performed in a short time.

Also, by using a guide groove substrate having an optical fiber guide groove as the optical fiber guide member,
Moreover, it can be realized with high productivity, and it has become easy to increase the number of cores.

[Brief description of drawings]

FIG. 1 is an explanatory view of a specific example of the single-fiber optical connector ferrule of the present invention, in which FIG. 1 (a) is a longitudinal sectional view and FIG. 1 (b) is (i).
It is a left end view of the optical fiber guide member of the figure. 2 and 3 are explanatory views of the multi-fiber optical connector ferrule of the present invention, and (a) is a longitudinal sectional view,
(B) is a left end view of (a). FIG. 4 is a longitudinal sectional view of an example of a conventional single-core optical connector,
The figure is an external view of an example of a conventional multi-fiber optical connector. A ... Optical fiber core wire, B ... Optical fiber, 1 ... Optical fiber guide member, 2 ... Guide member main body, 3 ... Tip guide member, 4 ... Optical fiber guide groove, 4 '... Optical Fiber guide hole, 5 ... Optical fiber core wire guide groove,
5 '... optical fiber core wire guide hole, 6, 10 ... guide groove substrate, 7, 11 ... flat plate, 8 ... optical fiber guide groove, 8' ... optical fiber guide hole, 9 ... guide pin Groove, 9 '... Guide pin hole, 12 ... Pre optical fiber, 13 ... Guide pin, 14 ... Tip end face, 15 ... Rear end face, 16 ... Outer peripheral metal pipe, 17 ... Resin molding Department, 18
...... Outer circumferential groove, 20, 40 ...... Optical fiber guide member, 21,
41 …… Guide member body, 22, 42 …… Tip guide member,
23, 25, 43 …… Guide groove substrate, 24, 26, 44, 45 …… Flat plate, 27, 47 …… Pre optical fiber, 28, 46 ……
Steps, 29, 50 ... UV curable adhesive, 48 ... Recesses.

Claims (5)

(57) [Claims] 1. An optical connector ferrule for positioning and holding an optical fiber to realize a coupling, a tip guide member having a pre-optical fiber positioned and held in advance, and a tip thereof being polished, and an optical fiber communicating with the pre-optical fiber inside. An optical connector ferrule comprising an optical fiber guide member in which an end face of the guide member main body provided with a fiber guide hole is in contact with and is axially connected. 2. The optical connector ferrule according to claim 1, wherein an ultraviolet curable adhesive having a refractive index matching agent function is previously injected into the optical fiber guide hole. 3. The pre-optical fiber of the tip end guide member and the optical fiber guide hole of the guide member main body are connected by a V-groove guide plate having an optical fiber guide V-groove. The optical connector ferrule according to the first section. 4. The optical connector ferrule according to claim 1, wherein an end surface of the tip end guide member on the guide member body side is also polished in advance. 5. The optical connector ferrule according to claim 1, wherein the polishing is realized by collectively grinding the optical fiber and its peripheral members.