JP3770961B2 - Optical connector and assembly method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention mainly relates to a multi-fiber optical connector, and more particularly to a connector that can satisfactorily assemble a non-polished optical connector at a work site.
[0002]
[Prior art]
As a multi-fiber optical connector, there is a resin square MT (Mechanically Trasferable) connector, which has been put into practical use. The following description will be given for the case where the MT connector is used. However, the present invention is not limited to the MT connector, and can be applied to other optical connectors.
[0003]
For convenience of explanation, the MT connector will be briefly described first.
An example is shown in FIG.
20 is the whole ferrule,
22 is a fiber hole (the optical fiber 12 is inserted),
24 is a guide pin hole (a guide pin (not shown) is inserted),
Reference numeral 26 denotes a window (inserting adhesive from here as described later).
Reference numeral 10 denotes the entire tape core.
[0004]
Next, a conventional method for assembling a connector without polishing in the field will be described with reference to FIG.
(1) A positioning block 30 is used ((a) in the figure). This is a rectangular block shape in which at least one surface is precisely polished.
The ferrule 20 whose tip surface is polished is abutted against the polishing surface of the positioning block 30 and a pressing force F is applied.
This is usually performed on a jig (not shown).
(2) Insert the optical fiber 12 of the tape core wire 10 into the fiber hole of the ferrule 20, apply a pressing force F to the tape core wire 10, and press the tip of the optical fiber 12 against the positioning block 30 (FIG. )).
(3) Adhesive 28 is injected from the window 26 to fix the tape core wire 10 and the ferrule 20 (FIG. 3C).
{Circle around (4)} The ferrule 20 is separated from the positioning block 30 (and the jig) to complete the assembly ((d) in the figure).
[0005]
[New proposed technology 1]
However, one of the problems with the MT connector assembly is that the optical conduction of the connector cannot be confirmed until completion. If the assembled connector is defective, it must be discarded.
[0006]
In order to solve this problem, the following method has been proposed.
This will be briefly described below with reference to FIG.
{Circle around (1)} As shown in FIG. 5A, a short tape core wire 11 and an optical power meter 32 are attached to the reference plug 21S of the MT connector.
{Circle around (2)} The ferrule 20 whose tip surface has been polished is coupled to the reference plug 21 using a guide pin 34 and a clamp spring 36 as shown in FIG.
A matching oil is applied to the abutting surfaces.
(3) Then, the optical fiber 12 of the tape core wire 10 is inserted into the fiber hole 22 of the ferrule 20 as shown in FIG.
(4) Then, for example, light is sent from the light source 38 placed at the end of the tape core wire 10 and monitored by the optical power meter 32 to determine whether the ferrule 20 is good or bad. Discard defective products at this stage.
(5) Only non-defective products are fixed to the tape core 10 by injecting an adhesive 28 into the window 26 as shown in FIG.
{Circle around (6)} Finally, the reference plug 21S and the light source 38 are removed to complete the non-polishing assembly ((e) in the figure).
[0007]
[New proposed technology 2]
In addition, the assembly method of FIG. 4 requires the positioning block 30, and also requires the work of attaching and detaching the ferrule 20 to the positioning block 30. In particular, in the case of work on a pillar, etc., simplification is desired. ing.
[0008]
In order to solve this problem and eliminate the need to use the positioning block 30, the following method has been proposed.
This will be briefly described below with reference to FIG.
(1) In the figure (a), 21 is a ferrule already attached to the tape core wire 11 at the factory. The empty ferrule 20 is coupled to this using a guide pin 34 and a clamp spring 36, and matching oil is applied to the joint surface.
(2) The optical fiber 12 of the tape core wire 10 is inserted into the fiber hole 22 of the ferrule 20 and the tip of the optical fiber 12 is pressed against the ferrule 21 as shown in FIG.
(3) Adhesive 28 is injected from the window 26 to fix the tape core wire 10 and the ferrule 20 as shown in FIG.
As a result, the polishing assembly of the ferrule 20 is completed and the connection with the ferrule 21 is also completed.
[0009]
[Problems to be solved by the invention]
Taking the case of FIG. 6 as an example, when the optical fiber 12 is inserted into the fiber hole 22 as shown in a partially enlarged view in FIG. In some cases, bubbles 42 are mixed in.
If this bubble 42 remains, the connection loss increases.
In the case of the optical monitoring method of FIG. 5 described above, if there is a bubble 42 on the abutment surface of the ferrule, the optical monitor value becomes inaccurate.
[0010]
[Means for Solving the Problems]
As illustrated in FIG. 1, both upper and lower corners of the front end face of the ferrule 20 are cut away to form a bubble escape passage 23 whose one end is in contact with the upper and lower edges of the fiber hole 22. The air bubble 42 generated when the air hole is inserted is allowed to escape through the escape passage 23, thereby removing the optical obstacle on the fiber hole surface.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The case illustrated in FIG. 1 will be described. The upper and lower corners (ridge angles) of the front end face of the ferrule 20 are obliquely cut out on a plane including virtual straight lines in contact with the upper and lower edges of the fiber hole 22 to create the escape passage 23.
[0012]
This escape passage 23 is formed by cutting the ferrule 20 after molding. Moreover, this shape can also be produced on a metal mold | die.
[0013]
If the ferrule 20 has such a structure, for example, as in the case of FIG. 6 described above, when the optical fiber 12 is inserted into the fiber hole 22 as a result of abutting with the ferrule 21 (FIG. 1B), Even if the bubbles 42 are mixed into the matching oil 40 on the mating surface, they escape through the escape passage 23 and do not remain on the fiber hole surface.
[0014]
[Deformation of escape 23]
In the case of FIG. 1 described above, the escape passage 23 is formed over the entire lateral width of the ferrule 20. However, as shown in FIG. 2, the escape passage 23 may be provided only in the width portion where the fiber hole 22 exists.
In addition, the shape of the escape passage 23 may be any shape as long as the bubbles 42 generated when the optical fiber 12 is inserted into the fiber hole 22 can escape. For example, a cut surface may be provided only on one side.
[0015]
【The invention's effect】
By providing an escape 23
(1) The light monitor value becomes accurate by the non-polishing assembly while monitoring the light in FIG.
(2) Increase in connection loss can be prevented in the non-polishing assembly using the connection terminal of FIG. 6 in place of the positioning block.
[Brief description of the drawings]
FIG. 1A is an explanatory diagram of an example of an embodiment of the present invention, and FIG.
FIG. 2 is an explanatory diagram of another example of the embodiment of the present invention.
FIG. 3 is an explanatory diagram of an MT connector and is common to the present invention and the prior art.
FIG. 4 is an explanatory view of a conventional polishing-free connection method.
FIG. 5 is an explanatory diagram of a newly proposed technique 1 which is an object to be solved by the present invention.
FIG. 6 is an explanatory diagram of a newly proposed technique 2 which is an object to be solved by the present invention.
[Explanation of symbols]
10, 11 Tape core 12 Optical fiber 20, 21 Ferrule 22 Fiber hole 23 Bubble escape 24 Guide pin hole 26 Window 28 Adhesive 30 Positioning block 32 Optical power meter 34 Guide pin 36 Clamp spring 38 Light source 40 Matching oil 42 Bubble

Claims (4)

Both the upper and lower corners of the front end face of the ferrule are cut away to create a bubble escape where one end is in contact with the upper and lower edges of the fiber hole, and the bubble generated when an optical fiber is inserted into the fiber hole An optical connector characterized in that it can escape through.   The optical connector according to claim 1, wherein the escape passage is formed over the entire width of the ferrule. Both the upper and lower corners of the front end face of the ferrule are cut away to create a bubble escape where one end is in contact with the upper and lower edges of the fiber hole, and the bubble generated when an optical fiber is inserted into the fiber hole Prepare a ferrule that can escape through, connect the ferrule to the reference plug, apply matching oil to the abutting surface, and insert the optical fiber of the tape core into the fiber hole of the ferrule A method for assembling an optical connector, comprising: injecting an adhesive into a window of the ferrule and fixing the same to a tape core, and then removing the reference plug from the ferrule. Both the upper and lower corners of the front end face of the ferrule are cut away to create a bubble escape where one end is in contact with the upper and lower edges of the fiber hole, and the bubble generated when an optical fiber is inserted into the fiber hole Providing a first ferrule adapted to escape through the first ferrule and coupling the first ferrule to a second ferrule already attached to a second tape core; Matching oil is applied to the joint surface with the ferrule, the optical fiber of the first tape core wire is inserted into the fiber hole of the first ferrule, and the adhesive is injected from the window of the first ferrule. An optical connector assembling method, wherein the first tape core wire and the first ferrule are fixed.

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