JPH11237524A - Optical connector manufacturing method - Google Patents

Abstract

(57) [Problem] To provide an optical connector manufacturing method for manufacturing an optical connector having a simple connection operation and good transmission characteristics. SOLUTION: An end portion of an optical fiber 1a, which is obtained by removing a coating portion from an optical fiber core wire 1 and exposed, is inserted into a positioning hole 2a in a ferrule 2, and a tip end of the optical fiber 1a is connected to a joint surface 2b of the ferrule 2. The state of the end of the optical fiber 1a is confirmed by protruding, and a pressing member 3A having a contact surface 3a that is in contact with the end surface of the optical fiber 1a is pressed against the joint surface 2b of the ferrule 2 to make contact with the end surface of the optical fiber 1a. The optical fiber 1 is connected to the ferrule 2 in a state where the optical fiber 1 contacts the contact surface 3a.
a is fixed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an optical connector for connecting optical fibers.

[0002]

2. Description of the Related Art In order to detachably connect optical fiber cores, it is common practice to attach a ferrule to an end of the optical fiber core to form an optical connector, and to connect the optical connectors. In such an optical connector, it is necessary to polish a joint surface between the optical connectors in order to reduce a connection loss at the time of connection. In other words, in order to attach the ferrule to the end of the optical fiber core at the connection site to form an optical connector, a polishing operation must be performed at the connection site. However, this polishing operation is very time-consuming and troublesome, and improvement in connection operation has been desired.

Therefore, as described in Japanese Patent Application Laid-Open No. 9-304657, a method for connecting optical connectors without performing a polishing operation has been proposed. According to the method described in Japanese Patent Application Laid-Open No. 9-304657, one optical connector is assembled by fixing an optical fiber to a ferrule having a joint surface polished in advance. Next, another ferrule whose joining surface is polished is joined to the optical connector, and an optical fiber is inserted into the joined ferrule. Then, the optical fiber is fixed to the ferrule while applying a constant load in the insertion direction of the optical fiber.

[0004]

However, according to the method described in Japanese Patent Application Laid-Open No. 9-304657, it is not possible to confirm how the ends of the optical fibers are joined together. For this reason, when the end of the optical fiber is damaged when the optical fiber is inserted and fixed in the ferrule, it cannot be recognized. Further, when connecting multi-core optical fiber cores, if the amount of irregularity of the ends of the optical fibers is large, a gap (gap) is generated between the end faces of the optical fibers, and good transmission characteristics may not be obtained. .

Accordingly, it is an object of the present invention to provide a method for manufacturing an optical connector for manufacturing an optical connector having a simple transmission operation and good transmission characteristics.

[0006]

According to a first aspect of the present invention, an end of an optical fiber exposed by removing a coating portion from an optical fiber is inserted into a positioning hole in a ferrule.
The state of the end of the optical fiber is checked by projecting the tip of the optical fiber from the joint surface of the ferrule, and a pressing member having a contact surface that comes into contact with the end surface of the optical fiber is pressed against the joint surface of the ferrule, and It is characterized in that the optical fiber is fixed to the ferrule in a state where a load is applied so that the end face and the contact surface can be brought into contact.

According to a second aspect of the present invention, in the first aspect, the pressing member has a convex portion inserted into the positioning hole, and the convex surface of the convex portion is an abutting surface. The fiber is fixed in a state where the tip of the fiber is pushed into the inside by a predetermined amount from the end of the positioning hole.

According to a third aspect of the present invention, in the first aspect of the invention, the pressing member has a concave portion facing the end opening of the positioning hole, and the concave surface of the concave portion is an abutting surface;
The optical fiber is fixed in a state where the tip of the optical fiber protrudes from the end of the positioning hole by a predetermined amount.

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, prior to pressing the pressing member against the bonding surface of the ferrule, the refractive index matching is performed on the bonding surface or the abutting surface. It is characterized by applying an agent.

According to a fifth aspect of the present invention, in the first aspect of the present invention, the ferrule and the pressing member each have a pin hole for inserting a guide pin, and the ferrule and the pressing member are provided on the joint surface of the ferrule. When the pressing member is pressed, a guide pin is inserted from the pin hole of the ferrule to the pin hole of the pressing member to position the ferrule and the pressing member.

According to a sixth aspect of the present invention, the tip of the optical fiber is subjected to electrical discharge machining prior to inserting the optical fiber into the positioning hole. I have.

According to a seventh aspect of the present invention, in the first aspect, prior to inserting the optical fiber into the positioning hole, an edge removal process is performed on the tip of the optical fiber. And

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a method for manufacturing an optical connector according to the present invention will be described with reference to the drawings. In the following description, a so-called MT connector will be described as an example of an optical connector. However, the present invention can be used for manufacturing various multi-core optical connectors and single-core optical connectors other than the MT connector.

First, the structure of the MT connector will be described with reference to FIG.
This will be briefly described with reference to FIG.

As shown in FIGS. 1 and 2, the MT connector described here is composed of a four-core tape-shaped multi-core optical fiber 1 and a ferrule 2 attached to the tip of the optical fiber 1. Become. The optical fiber core 1 has four optical fibers 1a inside in parallel. The optical fiber core 1 shown in FIG. 1 has the resin coating at the end removed to expose the optical fiber 1a.

The ferrule 2 is a member made of a synthetic resin and has a form in which two rectangular parallelepipeds are joined, and a rectangular opening 2f is formed on the upper surface thereof. Opening 2
f communicates with an insertion hole 2g (see FIG. 2A) formed on the side into which the optical fiber 1 is inserted. Opening 2f
Are formed in parallel at the bottom thereof with four guide grooves 2c for guiding the optical fiber 1a of the inserted optical fiber core wire 1 into the positioning hole 2a. The distal end side of the guide groove 2c communicates with the proximal end side of the positioning hole 2a.

The positioning holes 2a are formed to penetrate from the inside of the ferrule 2 to the joint surface 2b, and four of them are parallel to the guide grooves 2c. The inner diameter of the positioning hole 2a is substantially equal to the outer diameter of the optical fiber 1a in order to position the optical fiber 1a inserted therein.

On both sides of the positioning hole 2a and the guide groove 2c, a pair of pin holes 2d are formed penetrating the inside of the ferrule 2. The pair of pin holes 2d are also arranged in parallel with the above-described positioning holes 2a and the guide grooves 2c. These pin holes 2d are used for positioning with a pressing member 3A, which will be described later, when manufacturing the optical connector, and for positioning with another optical connector when connecting to another optical connector. At this time, one ends of the guide pins 2e are inserted into the pin holes 2d, respectively, and these guide pins 2e are inserted.
Is inserted into the pressing member 3A or the pin hole 2d of another optical connector to perform positioning.

FIG. 2 shows an optical connector obtained by assembling the above-described optical fiber core 1 and ferrule 2 by a manufacturing method of the present invention using a pressing member 3A described later.

In the optical connector shown in FIG. 2, the tip of the optical fiber 1a is aligned at a position where it is pushed from the joint surface 2b of the ferrule 2 into the positioning hole 2a by a predetermined amount. Further, the optical fiber 1a inserted into the positioning hole 2a is moved by the adhesive 7 filled from the opening 2f.
The ferrule 2 is fixed. Further, a refractive index matching agent 6 is filled in the positioning hole 2a in the vicinity of the tip of the optical fiber 1a. Ferrule 2
A boot 4 for holding the inserted optical fiber 1 is attached to the side of the insertion hole 2g.

Next, the pressing member 3A used when assembling the optical connector shown in FIG. 2 will be described with reference to FIG.

The pressing member 3A is a member made of a synthetic resin similar to the ferrule 2, and has a form in which two rectangular parallelepipeds similar to the outer shape of the ferrule 2 are joined. At the center of the end surface of the pressing member 3A that comes into contact with the joint surface 2b of the ferrule 2, four columnar projections 3b corresponding to the positioning holes 2a of the ferrule 2 protrude. The convex surface of the convex portion 3b is a contact surface 3a that comes into contact with the end surface of the optical fiber 1a in the ferrule 2 when the pressing member 3A is pressed against the ferrule 2. The outer diameter of the projection 3b is substantially equal to the outer diameter of the optical fiber 1a. Also, the convex portion 3
The protrusion amount of b is equal to a predetermined amount (for example, 10 μm) by which the end face of the optical fiber 1a is pushed into the positioning hole 2a in the manufactured optical connector.

The ferrule 2 is provided on both sides of the convex portion 3b.
A pair of pin holes 3c corresponding to the pair of pin holes 2d are formed through the inside of the pressing member 3A. The pair of pin holes 3c are arranged in parallel with the projecting direction of the above-described protrusion 3b. As described above, these pin holes 3c are used for positioning with the ferrule 2 at the time of manufacturing the optical connector. FIG. 4 shows a state in which the pressing member 3A is pressed against the ferrule 2 when manufacturing the optical connector shown in FIG.
Shown in At this time, the end surface of the optical fiber 1a contacts the contact surface 3a of the projection 3b inserted into the positioning hole 2a,
The tip positions are aligned.

Next, a method of manufacturing the above-described optical connector will be described with reference to FIGS.

First, after the optical fiber 1 is inserted into the boot 4 [FIG. 5 (a)], the coated portion of the optical fiber 1 is removed by heating and softening with a heating type remover [FIG.
(b)]. The coating waste remaining around the optical fiber 1a exposed by removing the coating is wiped off with alcohol or the like. The exposed optical fiber 1a is cut into a predetermined length using a fiber cutter [FIG.
(c)]. The steps so far are no different from the conventional manufacturing method.

Next, the tip of the cut optical fiber 1a is subjected to electric discharge machining. By performing electrical discharge machining, the optical fiber 1a
Is melted to form a substantially hemispherical shape, so that the edge at the time of cutting can be eliminated and the inclination of the cut surface can be eliminated. As a result, connection loss can be reduced. Also, since the tip of the optical fiber 1a is hemispherical,
The optical fiber 1a can be smoothly inserted into the positioning hole 2a of the ferrule 2, and breakage of the optical fiber due to contact with the ferrule 2 when attached to the ferrule 2 can be prevented.

Alternatively, edge removal processing may be performed instead of electric discharge machining. The edge removal processing is performed using an edge processing apparatus (not shown) having a mortar-shaped rotating polishing plate,
The tip of the optical fiber 1a is pressed against the inner surface of the rotating polishing plate that is driven to rotate, and the outer circumference of the tip of the optical fiber 1a is several μm to
By removing several tens of μm, the optical fiber 1a
This is to remove the edge formed at the tip of. Also by the edge removal processing, the connection loss can be reduced as in the case of electric discharge machining, and the damage of the optical fiber at the time of attachment to the ferrule 2 can be prevented.

The optical fiber 1 whose end is treated and the ferrule 2 are set on a worktable (not shown), and the optical fiber 1 a is inserted into the positioning hole 2 a of the ferrule 2. The tip of 1a is protruded from the joint surface 2b by a predetermined amount (for example, 100 μm). In the case of a multi-core optical fiber, all ends protrude from the bonding surface 2b [FIG.
(d)]. With the distal end of the optical fiber 1a protruding from the joint surface 2b, the boot 4 is temporarily fixed to the ferrule 2, and at the same time, the optical fiber core 1 is gripped by the core grip 5 attached to the worktable [ FIG. 5 (e)].

Here, the state of the tip of the optical fiber 1a protruding from the bonding surface 2b is confirmed using a microscope, a CCD, or the like. Here, it is checked whether the tip of the optical fiber 1a is damaged. In the case of the multi-core optical fiber 1, it is also confirmed whether the irregular amount at the tip of the optical fiber 1 a is within an allowable range. This is because if the amount of irregularity at the ends of the optical fibers 1a is large, it may not be possible to align the ends of the optical fibers 1a using the pressing member 3A in a later step. If the ends of the optical fibers 1a cannot be aligned, even if the connection loss of one of the optical fibers 1a is within the allowable range, the connection loss of the other optical fiber 1a will be outside the allowable range.

This check can be easily performed by projecting the tip of the optical fiber 1a from the bonding surface 2b, and it is very difficult to check the state without protruding from the bonding surface 2b. As a result of checking, if the tip of the optical fiber 1a is damaged or the amount of irregularity is out of an allowable range, the optical fiber 1a is corrected by cutting again or performing electric discharge machining (edge removal processing) again.

After the end of the optical fiber 1a is confirmed, the refractive index matching agent 6 is formed around the contact surface 3a of the convex portion 3b while the optical fiber core 1 is held and fixed by the core holding portion 5.
The pressing member 3A coated with is applied to the ferrule 2 (FIG. 6A). At this time, the pair of guide pins 2e are moved from the pin holes 2d of the ferrule 2 to the pin holes 3 of the pressing member 3A.
c, and the ferrule 2 and the pressing member 3A are positioned. By positioning the ferrule 2 and the pressing member 3A, the positions of the positioning hole 2a and the projection 3b are aligned, and the projection 3b is positioned with respect to the positioning hole 2a.
Is inserted.

After attaching the pressing member 3A to the ferrule 2, a clamp spring 8 is attached from the ferrule 2 to the pressing member 3A so that the joint surface 2b and the end surface of the pressing member 3A are firmly joined. . At the same time, the load F is applied by sliding the core wire gripping portion 5 leftward in FIG.
6a is pressed against the contact surface 3a [FIG.
(b)].

In the state shown in FIG. 6B, the joining surface 2b
The optical fiber 1a protruding from the optical fiber 1a is slightly compressed by the compressive force applied to the optical fiber 1a, and the irregular tip is pushed into the positioning hole 2a to be aligned. If the ends of the optical fibers 1a (the optical fiber core wires 1) do not align with the compression of the optical fibers 1a alone, the ends of the optical fibers 1a (the optical fiber core wires 1), which are slightly bent but are uneven, are aligned. At this time, since the outer diameter of the optical fiber 1a is substantially equal to the inner diameter of the positioning hole 2a, the optical fiber 1a does not bend inside the positioning hole 2a, and the portion after the portion located in the guide groove 2c [shown by X in FIG. Range). These compressions and deflections are not so great as to deteriorate the transmission characteristics.

When the projection 3b is inserted into the positioning hole 2a, the optical fiber core 1 (optical fiber 1a) is
6 may be pushed by the convex portion 3b and slide rightward in FIG. 6 together with the core wire grasping portion 5, and then the load F may be applied by sliding the core wire grasping portion 5 leftward in FIG. .
Alternatively, when the convex portion 3b is inserted into the positioning hole 2a, the optical fiber core 1 is gripped by the core holding portion 5 so as not to slide, and the portion pushed back by the convex 3b is determined by the optical fiber core. The end face of the optical fiber 1a is pressed against the contact surface 3a by using only the force of the compression or deflection of the optical fiber 1a (the optical fiber 1a), and the compression or deflection is restored. The load F may not be applied.

Next, the state where the tip of the optical fiber 1a is pushed into the positioning hole 2a by a predetermined amount, that is, the state where a load F for applying the end face of the optical fiber 1a to the contact surface 3a is applied. Then, the adhesive 7 is filled into the ferrule 2 through the opening 2f, and the optical fiber 1 is
a is fixed (FIG. 6 (d)). This state is the state shown in FIG. 4 (however, the clamp spring 8 is not shown in FIG. 4). The optical fiber 1a is fixed to the ferrule 2 with its ends aligned, and the pressing member 3A
Even if the tip is removed, the tips will be aligned [Fig.
(d)].

Prior to filling the adhesive 7, the refractive index matching agent 6
Is filled in the vicinity of the tip of the optical fiber 1a. Therefore, even if the adhesive 7 fills the vicinity of the tip of the optical fiber 1a along the optical fiber 1a, the tip of the optical fiber 1a is covered with the refractive index matching agent 6. Therefore, the adhesive 7 does not adhere to the end face of the optical fiber 1a. Therefore, there is no possibility that the transmission loss is deteriorated due to the adhesion of the adhesive 7.

It should be noted that the adhesive 7 does not fill the tip of the positioning hole 2a and the optical fiber 1
a) (see FIG. 2), the optical fiber 1a is positively filled to the vicinity of the tip of the optical fiber 1a.
aThe bonding region may be formed up to the vicinity of the tip. When the connection operation is actually performed using the optical connector manufactured as described above, the refractive index matching agent 6 is attached to the tip of the positioning hole 2a.
Is further filled, so that the gap between the end faces of the optical fiber 1a to be connected is filled with the refractive index matching agent 6.

According to the above-described manufacturing method, when the ferrule 2 is attached to the end of the optical fiber core wire 1 at the connection site to make an optical connector, a polishing operation is not required, so that the optical connector is easily manufactured. be able to. As a result, the connection work at the connection site can be easily performed.

Further, according to the above-described manufacturing method, immediately before fixing the optical fiber 1a (the optical fiber core 1) to the ferrule 2, the tip of the optical fiber 1a is made to protrude from the joint surface 2b to change the state. To confirm, the optical fiber 1a
It is possible to confirm the breakage and irregularity of the tip of the optical connector, and to manufacture an optical connector having good transmission characteristics.

The optical connector manufactured by the above-described manufacturing method has stable transmission characteristics because the ends of the optical fiber 1a are aligned neatly. Further, in the optical connector manufactured using the pressing member 3A having the convex portion 3b, the tip of the optical fiber 1a has the positioning hole 2a.
So that they are aligned inside the so-called Hikari CATS (CAble Trans
Even when high-speed connection switching is performed using a fer-splicing system or the like, there is no possibility that the end of the optical fiber 1a will come into contact with the ferrule 2 and be damaged, making it suitable for high-speed connection switching.

What has been described so far has been the case where the leading ends of the optical fibers 1a are aligned inside the positioning holes 2a using the pressing member 3A shown in FIG. On the other hand, a case where the ends of the optical fibers 1a are aligned with the pressing members 3B shown in FIG. 7A protruding from the positioning holes 2a will be described below.

The optical fiber core 1 and the ferrule 2 used in this case are not different from those in the above-mentioned case, and therefore the description thereof is omitted here. In the pressing member 3B used in this case, as shown in FIG. 7A, a concave portion 3d corresponding to the positioning hole 2a of the ferrule 2 is formed at the center of the end surface that is in contact with the joint surface 2b of the ferrule 2. . The concave surface of the concave portion 3d is a contact surface 3a that comes into contact with the end surface of the optical fiber 1a in the ferrule 2 when the pressing member 3B is pressed against the ferrule 2. The depth of the concave portion 3d is determined in the optical connector after manufacturing.
The end face of the optical fiber 1a is set equal to a predetermined amount (for example, 10 μm) protruding from the bonding surface 2b.

By using this pressing member 3B, the above-mentioned FIG.
An optical connector is manufactured by the same steps as the steps shown in FIG. However, since the pressing member 3B has the concave portion 3d instead of the convex portion 3b, as shown in FIG. 8, the end surface of the optical fiber 1a is aligned and fixed while protruding from the bonding surface 2b. Is different.

According to this manufacturing method, since the polishing operation is not required at the connection site, the connection operation at the connection site can be easily performed, and the state of the optical fiber 1a is projected by projecting the tip of the optical fiber 1a from the positioning hole 2a. For confirmation, an optical connector having good transmission characteristics can be manufactured. In addition, since the ends of the optical fibers 1a are aligned, stable transmission characteristics are obtained. These effects are the same as those of the above-described optical connector manufacturing method shown in FIG.

The optical connector manufactured using the pressing member 3B having the concave portion 3d is suitable for so-called PC (Physical Contact) connection since the tip of the optical fiber 1a is projected and aligned from the positioning hole 2a. Becomes In particular, in the case of the PC connection of the multi-core optical fiber, it is difficult to bring all the optical fibers into contact in an optimal state. However, according to the manufacturing method using the pressing member 3B described above,
Since the ends of all the optical fibers of the multi-core optical fiber can be aligned neatly, the PC of the multi-core optical fiber
It is effective for connection.

In order to align the ends of the optical fiber 1a with the end of the optical fiber 1a protruding from the joint surface 2b of the ferrule 2, instead of the pressing member 3B shown in FIG. The pressing member 3C shown in (b) may be used. The pressing member 3C shown in FIG. 7 (b) is different from the concave portion 3d of the pressing member 3B shown in FIG.
d 'is formed, but the concave surface of the concave portion 3d'
a, and there is no difference in the function in use.
It can be used in exactly the same way as the pressing member 3B shown in FIG.

Further, depending on the pressing member 3A shown in FIG. 3, the tip of the optical fiber 1a can be aligned within the positioning hole 2a, and depending on the pressing members 3B and 3C shown in FIG. Were made to protrude from the bonding surface 2b. Here, the optical fiber 1
When it is desired to align the tip of a with the bonding surface 2b, the tip of the optical fiber 1a can be aligned with the bonding surface 2b by using the pressing member 3D shown in FIG. In the pressing member 3D shown in FIG. 9, neither a convex portion nor a concave portion is formed on the surface in contact with the bonding surface 2b, and this surface functions as the contact surface 3a. The pressing member 3D shown in FIG. 9 can be used according to exactly the same process as the pressing member 3A shown in FIG. 3 and the pressing members 3B and 3C shown in FIG.

The manufacturing method of the present invention is not limited to the above embodiment. For example, in the above embodiment, the optical fiber 1a is
Although the adhesive 7 is used for fixing the fixing member, the fixing may be performed by mechanical means without using the adhesive. Also, as described above, the manufacturing method of the present invention is applicable to various multi-core optical connectors and single-core optical connectors other than the MT connector.

In the above-described embodiment, the clamp members 8A, 3B, 3C and 3D are pressed against the ferrule 2 by using the clamp spring 8 generally used when connecting optical connectors. However, it may be pressed by another method such as a fixing jig. In the above-described embodiment, the refractive index matching agent 6 is applied to the contact surface 3.
Although the coating is performed on the side a, the coating may be performed near the end opening of the positioning hole 2a on the bonding surface 2b side. In the above-described embodiment, the optical fiber 1a protruding from the bonding surface 2b is used.
Although the state of the tip of the lens was confirmed by a microscope, it may be confirmed visually or by another means of a magnifying glass.

[0050]

According to the first aspect of the present invention, since it is not necessary to perform polishing after fixing the optical fiber to the ferrule, the ferrule is attached to the end of the optical fiber at the connection site or the like. Even when a connector has to be manufactured, the connection operation can be performed easily and quickly. In addition, since the tip of the optical fiber is projected from the joint surface and the state of the tip of the optical fiber is checked, it is possible to check the damage and irregularity of the tip of the optical fiber, and to manufacture an optical connector having good transmission characteristics. it can. Further, the manufactured optical connector has stable transmission characteristics because the ends of the optical fiber are aligned neatly.

According to the second aspect of the present invention, since the pressing member has the convex portion, the manufactured optical connector has a so-called optical CATS ( Even when high-speed connection switching is performed using a CAble Transfer Splicing system, there is no possibility that the end of the optical fiber will be in contact with the ferrule and be damaged, making it suitable for high-speed connection switching.

According to the third aspect of the present invention, since the pressing member has the concave portion, the manufactured optical connector can be aligned by projecting the tip of the optical fiber from the positioning hole.
This is suitable for so-called PC (Physical Contact) connection. The optical connector manufactured by the pressing member having the concave portion is particularly effective with respect to the PC connection of the multi-core optical fiber where it has been difficult to make all the optical fibers contact in an optimal state.

According to the fourth aspect of the present invention, prior to the fixing of the optical fiber to the ferrule with the adhesive, the refractive index matching agent is applied to the bonding surface or the abutting surface, so that the optical connector manufactured is manufactured. An adhesive is filled in the vicinity of the tip of the optical fiber. For this reason, even if the adhesive runs along the optical fiber and is filled up to the vicinity of the tip, the adhesive does not adhere to the end face of the optical fiber covered with the refractive index matching agent, and the transmission loss due to the adhesion of the adhesive does not occur. There is no risk of deterioration.

According to the fifth aspect of the present invention, when the pressing member is pressed by the ferrule, the positioning is performed by inserting a guide pin from the pin hole on the ferrule side to the pin hole of the pressing member. For this reason, the ferrule and the pressing member can be accurately positioned, can be easily connected, and the connection operation can be easily performed.

According to the sixth aspect of the present invention, the tip of the optical fiber is melted into a substantially hemispherical shape by electric discharge machining, thereby eliminating edges at the time of cutting and tilting the cut surface. Can also be eliminated. As a result, connection loss can be reduced. In addition, since the tip of the optical fiber is hemispherical, the optical fiber can be smoothly inserted into the positioning hole of the ferrule, and damage to the optical fiber due to contact with the ferrule can be prevented.

According to the seventh aspect of the present invention, by removing the edge formed at the tip of the optical fiber at the time of cutting, the condition of the cut surface can be adjusted and the connection loss can be reduced. Further, by removing the edge, the optical fiber can be smoothly inserted without being caught when it is inserted into the positioning hole of the ferrule, and breakage of the optical fiber due to contact with the ferrule can be prevented.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an MT type optical connector.

FIGS. 2A and 2B are a sectional view and a plan view, respectively, showing a first embodiment of an optical connector manufactured by the method for manufacturing an optical connector of the present invention.

FIG. 3 is a perspective view showing a first embodiment of a pressing member used in the method for manufacturing an optical connector of the present invention.

FIG. 4 is a plan view (partial cross section) showing a state of joining and pressing the optical connector shown in FIG. 1 and the pressing member shown in FIG. 5;

FIG. 5 is a plan view showing an optical connector manufacturing process (first half) in the optical connector manufacturing method of the present invention.

FIG. 6 is a plan view showing a manufacturing process (second half) of the optical connector in the method for manufacturing an optical connector of the present invention.

FIG. 7 is a perspective view showing (a) a second embodiment, (b) and a third embodiment of a pressing member used in the optical connector manufacturing method of the present invention.

8 is a plan view (partial cross section) showing a state of joining and pressing between the optical connector shown in FIG. 1 and the pressing member shown in FIG. 7 (a).

FIG. 9 is a perspective view showing a fourth embodiment of a pressing member used in the method for manufacturing an optical connector of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical fiber core wire, 1a ... Optical fiber, 2 ... Ferrule, 2a ... Positioning hole, 2b ... Joint surface, 2c ... Guide groove,
2d: pin hole, 2e: guide pin, 2f: opening, 3
A, 3B, 3C, 3D: pressing member, 3a: contact surface (convex surface, concave surface), 3b: convex portion, 3c: pin hole, 3d, 3d '
... recesses, 4 ... boots, 5 ... core wire gripping parts, 6 ... refractive index matching agent, 7 ... adhesive, 8 ... clamp spring, F ... load.

Claims (7)

[Claims] 1. An end of an optical fiber exposed by removing a coating from an optical fiber core wire is inserted into a positioning hole in a ferrule, and the tip of the optical fiber is protruded from a joint surface of the ferrule. The state of the end of the optical fiber is checked, and a pressing member having a contact surface that is in contact with the end surface of the optical fiber is pressed against the joint surface of the ferrule, and the end surface of the optical fiber is brought into contact with the contact surface. A method for manufacturing an optical connector, comprising: fixing the optical fiber to the ferrule in a state where a load capable of contacting the optical fiber is applied. 2. The method according to claim 1, wherein the pressing member has a convex portion inserted into the positioning hole, a convex surface of the convex portion serving as the contact surface, and a tip of the optical fiber extending from an end of the positioning hole. The method for manufacturing an optical connector according to claim 1, wherein the optical connector is fixed while being pushed into the inside by a predetermined amount. 3. The positioning member according to claim 1, wherein the pressing member has a concave portion facing an end opening of the positioning hole, a concave surface of the concave portion is the contact surface, and a tip of the optical fiber is an end of the positioning hole. The method for manufacturing an optical connector according to claim 1, wherein the optical connector is fixed in a state where the optical connector is protruded by a predetermined amount. 4. The method according to claim 1, wherein a refractive index matching agent is applied to the joint surface or the contact surface before the pressing member is pressed against the joint surface of the ferrule. A manufacturing method of the optical connector according to the above. 5. The ferrule and the pressing member each have a pin hole for inserting a guide pin, and when pressing the pressing member against the joint surface of the ferrule,
The method for manufacturing an optical connector according to any one of claims 1 to 4, wherein the guide pin is inserted from the pin hole of the ferrule to the pin hole of the pressing member to position the ferrule and the pressing member. . 6. The method of manufacturing an optical connector according to claim 1, wherein, prior to inserting the optical fiber into the positioning hole, a tip of the optical fiber is subjected to electric discharge machining. 7. The method for manufacturing an optical connector according to claim 1, wherein prior to inserting the optical fiber into the positioning hole, an edge removing process is performed on a distal end of the optical fiber.