JP2020071360A - Ferrule for optical connectors and processing method for ferrule for optical connectors - Google Patents

Abstract

To provide a ferrule for optical connectors with which it is possible to reduce the inclusion of dust between ferrules for optical connectors when connecting the optical connectors with each other.SOLUTION: Provided is an MT ferrule 100 in which a pair of guide holes 2 are opened at one end face 1 and optical fiber insertion holes 3 are opened in a row between the pair of guide holes 2. The end face 1 has an inclined end face 12 where the optical fiber insertion holes 3 are opened and is inclined relative to an axis A of the pair of guide holes 2, the inclined end face 12 being characterized in that the upside of both sides across a center line segment C linking the opening centers of the pair of guide holes 2 is defined by a first boundary ridgeline 13 parallel to the center line segment C, and a rear region 5 receded from the inclined end face 12 is included in a region 41 outward from the pair of guide holes 2 out of a belt-like region 4 having a width twice an interval L1 between the center line segment C and the first boundary ridgeline 13.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an optical connector ferrule and an optical connector ferrule processing method, and more particularly, to an MT (suitable for configuring a multi-fiber optical fiber connector such as an MPO (Multi-fiber Push-on) connector. The present invention relates to a ferrule for an optical connector such as a mechanically transferable ferrule, and more particularly to a ferrule for an optical connector having an inclined end surface and a ferrule processing method for an optical connector for forming the ferrule for an optical connector.

  Patent Document 1 describes an example of a conventional ferrule for an optical connector. Patent Document 1 describes an optical connector ferrule in which a front end surface through which a fiber insertion hole penetrates is formed by a vertical surface and an inclined surface, and an optical connector ferrule formed by two or more vertical surfaces in a step shape. .. In these ferrules for optical connectors described in Patent Document 1, the polishing amount is reduced by obliquely polishing only a part of the front end surface with such a configuration.

JP, 2002-350681, A

  When connecting optical fibers with an optical connector using an optical connector ferrule such as an MT ferrule, a PC (Physical Contact) connection in which end faces of the optical fibers are butted and physically joined is generally adopted. When connecting the optical fibers to the PC, the end faces of the ferrule for an optical connector are brought into contact with each other or face each other with a slight gap (for example, 2 to 3 μm) therebetween.

Hereinafter, of the end faces of the optical connector ferrule, the end face portions that abut the mating optical connector ferrule at the time of PC connection or that face each other in a substantially parallel manner with a slight gap therebetween are referred to as "joint end faces" for convenience. Called.
Generally, when optical fiber ferrules 200 having a pair of guide holes 2 shown on the left side of FIG. In order to reduce the reflected return light, as shown in the right side of FIG. 7A, the end face 210 is polished to form an inclined end face 212, and the remaining end face portion is left as the vertical end face 211.
Then, when the ferrules for optical connector 200 are brought into contact with each other and the optical fibers are connected to each other by PC, as shown in FIG. 7B, a region of the end faces 210 where the inclined end faces 212 face each other is the joint end face 206. Become. In FIG. 7B, the region of the joint end surface 206 is indicated by a thick line for convenience.

  By the way, when connecting the optical connector, dust may be trapped between the joining end faces 206 of the ferrule for the optical connector. When the dust is trapped, the distance between the joint end faces 206 becomes long, or the joint end faces 206 are not parallel to each other, which may increase the connection loss and deteriorate the optical characteristics.

  The present invention has been made in view of the above circumstances, and an optical connector ferrule and an optical connector ferrule capable of reducing the inclusion of dust between the optical connector ferrules when connecting the optical connectors to each other. The purpose is to provide a processing method.

  The optical connector ferrule according to the present invention has an end surface facing the mating optical connector ferrule, a pair of guide holes are formed in the end surface, and an optical fiber is provided between the openings of the pair of guide holes in the end surface. An optical connector ferrule in which insertion holes are arranged and opened, wherein the end surface has an inclined end surface in which the optical fiber insertion hole is opened and is inclined with respect to an axis of the pair of guide holes, At least one side of the end surface sandwiching a center line segment connecting the opening centers of the pair of guide holes is defined by a boundary ridge line parallel to the center line segment, and viewed from the axial direction of the pair of guide holes. Of the strip-shaped area extending twice with the center line segment as the center line and having a width twice as large as the interval between the center line segment and the boundary ridge line closest to the center line segment. Also the center At least a portion of the minute extending outwardly of the region, is characterized by having a receding area recessed from the plane in which the inclined end face forms.

  The first optical connector ferrule processing method according to the present invention includes an end surface facing the mating optical connector ferrule, and a pair of guide holes are formed in the end surface, and the pair of guide holes of the end surface are provided. Is a ferrule processing method for an optical connector for processing an optical connector ferrule in which optical fiber insertion holes are arranged between the openings of the optical fiber insertion hole, the end face is ground, and the optical fiber insertion hole is opened, Inclined with respect to the axis of the guide hole, and at least one side on both sides of the center line connecting the opening centers of the pair of guide holes is defined by a boundary ridge line parallel to the center line. An inclined end face forming step of forming an end face, and extending from the center line segment as a center line when viewed from the axial direction of the pair of guide holes, between the center line segment and the boundary ridge line closest to the center line segment. Of the strip-shaped region having a width twice the distance, at least a part of the region outside the pair of guide holes in the extending direction of the center line segment is ground to retreat beyond the plane formed by the inclined end face. And a receding region forming step of forming a region.

  A second method for processing a ferrule for an optical connector according to the present invention includes an end face facing the mating ferrule for an optical connector, wherein a pair of guide holes are formed in the end face, and the pair of guide holes on the end face are provided. Is a ferrule processing method for an optical connector for processing an optical connector ferrule in which optical fiber insertion holes are arranged and opened between openings of the optical connector ferrule, the opening of the pair of guide holes in the end face of the optical connector ferrule. Than, a grinding portion forming step of forming at least a part of a region outside the extending direction of a center line segment connecting the opening centers of the pair of guide holes to form a grinding portion, and grinding the end surface, At least one side on both sides of the center line segment that is inclined with respect to the axis of the pair of guide holes forms an inclined end surface defined by a boundary ridge line parallel to the center line segment. And a center line segment extending with the center line segment as a center line when viewed in the axial direction of the pair of guide holes in the slope end face forming step. Of the strip-shaped region having a width twice as large as the distance from the boundary ridge line closest to the at least one of the guide holes, at least a part of the region outside the pair of guide holes in the extending direction of the center line is the remaining portion of the grinding portion. It is characterized in that a receding region receding from a plane formed by the inclined end face is formed.

  According to the ferrule for an optical connector and the ferrule processing method for an optical connector of the present invention, it is possible to reduce the amount of dust attached to the joint end face by reducing the area of the joint end face of the ferrule for the optical connector. As a result, when the optical connectors are connected to each other, it is possible to reduce dust trapping between the optical connector ferrules.

It is explanatory drawing of the ferrule for optical connectors which concerns on 1st Embodiment of this invention, (a) is a front view, (b) is an II sectional view of (a). It is explanatory drawing of the optical connector ferrule which concerns on 2nd Embodiment of this invention, (a) is a side view, (b) is a front view, (c) is the side surface of the optical connector ferrule joined by PC. It is a figure. It is explanatory drawing of the ferrule for optical connectors which concerns on 3rd Embodiment of this invention, (a) is a side view, (b) is a front view, (c) is a ferrule for optical connectors joined by PC. It is a side view. (A)-(c) is process drawing of the ferrule processing method for optical connectors which concerns on 4th Embodiment of this invention. (A)-(d) is process drawing of the ferrule processing method for optical connectors which concerns on 5th Embodiment of this invention. (A)-(c) is process drawing of the ferrule processing method for optical connectors which concerns on 6th Embodiment of this invention. FIG. 3A is a perspective view of an optical connector ferrule of a conventional example before and after polishing an end surface, and FIG. 3B is a side view of a PC-bonded ferrule for an optical connector.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
An MT ferrule as an optical connector ferrule according to a first embodiment of the present invention will be described with reference to FIG.
FIG. 1 (a) schematically shows a front view of the end surface of the MT ferrule of the present embodiment as seen from the axial direction of the guide hole, and FIG. 1 (b) shows I of the MT ferrule shown in FIG. 1 (a). The cross-sectional view along the line -I is shown typically.

As shown in FIGS. 1A and 1B, the MT ferrule 100 includes an end face 1 that faces the MT ferrule which is a ferrule for an optical connector on the mating side. The end face 1 has, for example, a substantially rectangular shape with a height H = 2.5 mm and a lateral width W = 6.4 mm in accordance with the “JIS C5982” standard of an F13 type multi-core optical fiber connector (MPO connector).
The MT ferrules in the other embodiments also have dimensions and shapes that comply with the "JIS C5982" standard in principle.

As shown in FIG. 1A, a pair of guide holes 2 are opened in the end face 1. The pitch of the pair of guide holes 2 is, for example, 4.6 mm according to the “JIS C5982” standard, and the diameter of the guide holes 2 is also 0.7 mm, according to the “JIS C5982” standard.
The MT ferrule 100 may be a female type in which guide pins are not inserted in the pair of guide holes 2 or may be a male type in which guide pins are inserted in the pair of guide holes 2.

Further, as shown in the figure, between the pair of guide holes 2 of the end face 1, four optical fiber insertion holes 3 are arranged in a line on a center line segment C connecting the opening centers of the pair of guide holes 2. Are arranged.
The number of the optical fiber insertion holes 3 is not limited to four, and may be two or more, such as 12 or 16. The arrangement of the optical fiber insertion holes 3 is not limited to one row, and may be a plurality of rows such as two rows or four rows.

As shown in FIG. 1B, the end face 1 has a vertical end face 11 orthogonal to the axis A of the pair of guide holes 2 and an inclined end face 12 inclined with respect to the vertical end face 11.
The inclined end face 12 is inclined by θ = 8 ° with respect to the vertical end face 11 in order to prevent reflected return light. That is, the normal h of the inclined end surface 12 is inclined by θ = 8 ° with respect to the axis A of the pair of guide holes 2 in the direction orthogonal to the plane including the pair of guide holes 2.

The inclined end face 12 is defined by a first boundary ridge line 13 parallel to the center line segment C that forms a boundary between the vertical end face 11 and the inclined end face 12 on the upper side of the drawing on both sides of the center line segment C. There is. On the other hand, the lower side of the inclined end face 12 is defined by the lower end edge B of the end face 1.
Then, as shown in FIG. 1A, the optical fiber insertion holes 3 are arranged and opened in the inclined end face 12.

When the MT ferrule 100 is joined to the mating MT ferrule, the mating MT ferrule is turned upside down and a part of the inclined end face 12 is joined, as in the conventional example shown in FIG. 7B. ..
As a result, of the inclined end surface 12 shown in FIG. 1A, the center line segment C and the first boundary ridge line 13, which is the boundary ridge line closest to the center line segment C, extend with the center line segment C as the center line. Only the strip-shaped region 4 having a width (2 × L1) that is twice the interval L1 of the other contact with the MT ferrule of the other side at the time of PC connection for joining with the MT ferrule 100 of the other side, or are separated from each other with a slight gap. The joining end surfaces may face each other substantially in parallel.

Then, in the MT ferrule 100 of the present embodiment, as shown in FIG. 1 (a), the region 41 of the strip-shaped region 4 outside the pair of guide holes 2 in the extending direction of the center line segment C has an inclined end surface. It is set as a receding area 5 receding from the plane formed by. In the same figure, the receding area 5 is shown with dot hatching. Therefore, of the strip-shaped region 4, only the region hatched with diagonal lines between the pair of guide holes 2 substantially becomes the joining end face 6.
Note that the receding area 5 may be only a part of the outer area 41 or the entire area 41. The shape of the receding region 5 is not particularly limited, and may be, for example, a notch shape or a shape in which both end edges of the MT ferrule 100 are chamfered.

  As a result, the area of the joining end face 6 can be reduced by the area of the receding region 5 rather than the area of the strip region 4. As a result, when connecting the optical connectors, it is possible to reduce the trapping of dust on the joint end surface between the MT ferrules 100.

(Second embodiment)
An MT ferrule as an optical connector ferrule according to the second embodiment of the present invention will be described with reference to FIG.
FIG. 2A is a side view of the MT ferrule of the present embodiment, and FIG. 2B is a front view of the end surface of the MT ferrule shown in FIG. 2A viewed from the axial direction of the guide hole. FIG. 2C is a side view of the PC-bonded ferrule for an optical connector.

Like the MT ferrule 100 of the first embodiment, the MT ferrule 100a of the present embodiment also has a size and shape that conforms to the "JIS C5982" standard in principle.
As shown in FIG. 2A, the MT ferrule 100a of the present embodiment also has a vertical end face 11a on the end face 1a, which is orthogonal to the axis A of the pair of guide holes 2, and an inclined end face inclined with respect to the vertical end face 11a. 12a.

  The inclined end surface 12a is defined by a first boundary ridge line 13a parallel to the center line segment C that forms a boundary between the vertical end surface 11 and the inclined end surface 12 on the upper side of the drawing on both sides of the center line segment C. There is. On the other hand, the lower side of the inclined end face 12 is defined by the lower end edge B of the end face 1.

However, in the "JIS C5982" standard, the distance L from the upper edge U of the vertical end surface 11 on the opposite side of the first boundary ridge 13 to the first boundary ridge 13 is specified to be 0.8 mm or less. In this embodiment, the distance L is longer than 0.8 mm. Further, as shown in FIG. 2A, this distance L is greater than the distance from the lower edge B to the opening of the optical fiber insertion hole 3 so that the opening 30 of the optical fiber insertion hole 3 opens to the inclined end face 12a. Is also short.
More specifically, as shown in FIG. 2B, the extension line of the first boundary ridgeline 13 a crosses the openings of the pair of guide holes 2. The first boundary ridgeline 13 may be in contact with the pair of guide holes 2.

  As a result, of the inclined end surface 12a shown in FIG. 2A, the center line segment C and the first boundary ridge line 13a, which is the boundary ridge line closest to the center line segment C, extend with the center line segment C as the center line. The width of the strip-shaped region 4a which is twice the width L2 (2 × L2) can be narrowed.

Then, in the MT ferrule 100a of the present embodiment, as shown in FIG. 2 (b), the inclined end surface is provided in a region outside the pair of guide holes 2 in the extending direction of the center line segment C in the strip-shaped region 4a. A receding region 5a is formed which is receded from the plane formed.
In particular, in this embodiment, the recessed region 5a is formed by grinding the region including the ridge line portion that extends the first boundary ridgeline 13a to the outside of the pair of guide holes.
As a result, only the region between the pair of guide holes 2 in the strip-shaped region 4a becomes the joining end face 6a.
The recessed region 5a may have a notched shape as shown in FIG. 2B, or may have a shape in which both end edges of the MT ferrule 100a are chamfered.

  In FIG. 2B, a region that becomes the joining end surface 6a when the MT ferrules 100a are joined is shown by hatching. Further, FIG. 2C shows a side view of the MT ferrule 100a joined to the MT ferrule 100a of the opposite side which is turned upside down. In the same figure, the region of the joint end face 6a is indicated by a thick line for convenience.

As described above, in this embodiment, since the receding region 5a is formed and the width of the band-shaped region 4a is narrower than that of the first embodiment, the area of the joint end face 6a can be further reduced. You can
As a result, it is possible to further reduce the amount of dust trapped in the joining end surface 6a of the MT ferrule 100a when connecting the optical connectors.

(Third Embodiment)
An MT ferrule as an optical connector ferrule according to the third embodiment of the present invention will be described with reference to FIG.
FIG. 3A is a side view of the MT ferrule of the present embodiment, and FIG. 3B is a front view of the end surface of the MT ferrule shown in FIG. 3A as seen from the axial direction of the guide hole. Yes, FIG. 3C is a side view of the PC-bonded MT ferrule.

Similarly to the MT ferrule 100 of the first embodiment, the MT ferrule 100b of this embodiment also has a size and shape that conforms to the "JIS C5982" standard in principle.
As shown in FIG. 3A, the MT ferrule 100b of this embodiment also has a vertical end face 11b on the end face 1b, which is orthogonal to the axis A of the pair of guide holes 2, and an inclined end face inclined with respect to the vertical end face 11b. 12b and.

The inclined end face 12b is defined by a first boundary ridge line 13b parallel to the center line segment C that forms a boundary between the vertical end face 11b and the inclined end face 12b on both sides of the center line segment C on the upper side of the drawing. There is.
Then, as shown in FIG. 3A, the optical fiber insertion holes 3 are arranged and opened in the inclined end face 12b.

  Further, the end surface 1b of the MT ferrule 100b has a retreat portion 7 on the opposite side of the first boundary ridgeline 13b with the center line segment C interposed therebetween and retracted from the plane P formed by the inclined end surface 12b. Therefore, the lower side of the inclined end surface 12b is defined by the second boundary ridge line 14 that forms the boundary between the inclined end surface 12b and the receding portion 7.

  As shown in FIG. 3A, in the present embodiment, the retreat portion 7 is an inclined flat surface, but the shape of the retreat portion 7 is not limited to this, and even if it is a cutout shape when viewed from the side, for example. It may be a curved shape when viewed from the side.

As shown in FIG. 3B, an extension line of the second boundary ridge line 14 crosses the openings of the pair of guide holes 2. Therefore, in the present embodiment, the second boundary ridgeline 14 is closer to the center line segment C than the first boundary ridgeline 13b, and thus the second boundary ridgeline 14 is the closest boundary ridgeline.
The first boundary ridgeline 13b may be in contact with the openings 20 of the pair of guide holes 2.

  As a result, of the inclined end surface 12b shown in FIG. 3A, the center line segment C extends along the center line segment C and the second boundary ridge line 14 that is the boundary ridge line closest to the center line segment C. The width of the strip-shaped region 4b, which is twice the width L2 (2 × L3), can be narrowed.

Then, in the MT ferrule 100b of the present embodiment, as shown in FIG. 3 (b), the inclined end surface is formed in a region outside the pair of guide holes 2 in the extending direction of the center line segment C in the strip-shaped region 4b. A receding region 5b receding from the plane P is formed.
In particular, in the present embodiment, the recessed region 5b is formed by grinding the region including the ridge portion that extends the second boundary ridge line 14 to the outside of the pair of guide holes 2.
As a result, only the region between the pair of guide holes 2 in the strip-shaped region 4b becomes the joining end face 6b.

  In FIG. 3B, the region that becomes the joining end face 6b when the MT ferrules 100b are joined together is shown with hatching. Further, FIG. 3C shows a side view of the MT ferrule 100b joined to the MT ferrule 100b of the opposite side which is turned upside down. In the figure, the region of the joint end surface 6b is indicated by a thick line for convenience.

As described above, in this embodiment, since the receding region 5b is formed and the width of the band-shaped region 4b is made narrower than that of the first embodiment, the area of the joint end face 6b can be further reduced. it can.
As a result, when optical connectors are connected to each other, it is possible to further reduce the amount of dust trapped in the joining end surface 6b of the MT ferrule 100b.

(Fourth Embodiment)
A ferrule processing method for an optical connector according to a fourth embodiment of the present invention will be described with reference to FIG. FIG. 4A to FIG. 4C are process diagrams of the method for processing a ferrule for an optical connector according to this embodiment.

In the present embodiment, the end face 10 facing the ferrule for the optical connector on the mating side shown in FIG. 4A is provided, and a pair of guide holes 2 are opened in the end face 10, and between the pair of guide holes 2 of the end face 1. A processing method for forming the MT ferrule 100a described in the second embodiment by processing the MT ferrule 300 as an optical connector ferrule in which the optical fiber insertion holes 3 are arranged and opened will be described.
As shown in FIG. 4A, in this embodiment, the entire initial end surface 10 of the MT ferrule 300 to be processed is a vertical end surface orthogonal to the axis A (see FIG. 2) of the pair of guide holes 2. There is.

<Inclined end face forming step>
First, the initial end face 10 which is a vertical end face is ground to open the optical fiber insertion hole 3 and form an inclined end face 12a inclined with respect to the axis A of the pair of guide holes 2 (FIG. 2 (a)). )reference).
In the present embodiment, as shown in FIG. 4B, in the inclined end face forming step, the boundary between the vertical end face 11a and the inclined end face 12a is parallel to the center line segment C connecting the opening centers of the pair of guide holes 2. The first boundary ridgeline 13a is formed. The upper side of the inclined end face 12a is defined by the first boundary ridgeline 13a which is the closest boundary ridgeline.

<Recessed area forming step>
Next, when viewed from the direction of the axis A of the pair of guide holes 2, the distance between the center line segment C and the first boundary ridge line 13a immediately adjacent to the center line segment C, which extends with the center line segment C as the center line, is 2 Of the strip-shaped region 4a having a double width, at least a part of the region outside the pair of guide holes 2 in the extending direction of the center line segment C is ground, and the recessed region is recessed from the plane P formed by the inclined end face 12. 5a is formed (see FIGS. 2B and 2C).

In the present embodiment, as shown in FIG. 4C, in the receding region forming step, the region including the ridgeline portion outside the pair of guide holes 2 of the first boundary ridgeline 13a is ground to form the receding region 5a. To form.
In this way, the MT ferrule 100a described in the second embodiment is formed.

(Fifth Embodiment)
A ferrule processing method for an optical connector according to a fifth embodiment of the present invention will be described with reference to FIG. FIG. 5A to FIG. 5D are process drawings of the ferrule processing method for an optical connector according to this embodiment.

In the present embodiment, an end face 10 facing the mating optical connector ferrule shown in FIG. 5A is provided, and a pair of guide holes 2 are opened in the end face 10, and between the pair of guide holes 2 of the end face 10. A processing method for forming the MT ferrule 100b described in the third embodiment by processing the MT ferrule 300 as an optical connector ferrule in which the optical fiber insertion holes 3 are arranged and opened.
As shown in FIG. 5A, in the present embodiment, the entire initial end surface 10 of the MT ferrule 300 to be processed is a vertical end surface orthogonal to the axis A of the pair of guide holes 2.

<Inclined end face forming step>
First, the initial end face 10 which is a vertical end face is ground to open the optical fiber insertion hole 3 and form an inclined end face 12b inclined with respect to the axis A of the pair of guide holes 2 (FIG. 3 (a)). )reference).
As shown in FIG. 5B, in the present embodiment, in the inclined end face forming step, the opening of the pair of guide holes 2 is formed at the boundary between the vertical end face 11b, which is the grinding residual portion of the vertical end face 10, and the inclined end face 12b. A first boundary ridgeline 13b parallel to the center line segment C connecting the centers is formed. The upper side of the inclined end surface 12b is defined by the first boundary ridgeline 13b.

<Recessed portion forming step>
Next, on the opposite side of the first boundary ridgeline 13b across the center line segment C of the inclined end surface 12 of the end surfaces 10, the retreat portion 7 that is recessed from the plane P formed by the inclined end surface 12b is formed (FIG. 3). (A) and FIG.3 (b)).
As shown in FIG. 5C, in the present embodiment, in the receding part forming step, a second boundary ridge line parallel to the center line segment C is provided as a boundary ridge line closest to the boundary between the inclined end surface 12b and the receding part 7. 14 is formed.

<Recessed area forming step>
Next, when viewed from the direction of the axis A of the pair of guide holes 2, the distance between the center line segment C and the second boundary ridge line 14 immediately adjacent to the center line segment C, which extends with the center line segment C as the center line, is 2 Of the band-shaped region 4b having a double width, at least a part of the region 41 outside the pair of guide holes 2 in the extending direction of the center line segment C is ground to retreat beyond the plane P formed by the inclined end face 12. A region 5b is formed (see FIGS. 3A and 3B).

In the present embodiment, as shown in FIG. 5D, in the receding region forming step, the receding region 5b is ground by grinding the region of the second boundary ridgeline 14 including the ridge portion outside the pair of guide holes 2. Form.
In this way, the MT ferrule 100b described in the third embodiment is formed.

(Sixth Embodiment)
A ferrule processing method for an optical connector according to a sixth embodiment of the present invention will be described with reference to FIG. FIG. 6A to FIG. 6C are process diagrams of the method for processing a ferrule for an optical connector according to this embodiment.

In the present embodiment, the end face 10 facing the mating optical connector ferrule shown in FIG. 6A is provided, and a pair of guide holes 2 are opened in the end face 10, and between the pair of guide holes 2 of the end face 1. A processing method for forming the MT ferrule 100c by processing the MT ferrule 300 as an optical connector ferrule in which the optical fiber insertion holes 3 are arranged and opened will be described.
As shown in FIG. 6A, in the present embodiment, the MT ferrule 300 to be machined is such that the entire initial end surface 10 is a vertical end surface orthogonal to the axis A of the pair of guide holes 2.

<Grinding part forming process>
First, as shown in FIG. 6B, in the end face 10 of the MT ferrule 300, a region outside the pair of guide holes 2 in the extending direction of the center line segment C connecting the opening centers of the pair of guide holes 2. At least a part of is ground to form a ground portion 8. In this embodiment, as shown in the figure, both end edges of the MT ferrule 300 are chamfered to form the ground portion 8.

<Inclined end face forming step>
Next, as shown in FIG. 6C, the vertical end face 10 is ground to be inclined with respect to the axis A of the pair of guide holes 2 and on the drawing of both sides sandwiching the center line segment C. The side forms an inclined end face 12c defined by a first boundary ridge line 13c parallel to the center line segment C. A portion of the vertical end surface 10 that has not been ground remains as a vertical end surface 11c.

Further, in the inclined end face forming step, when viewed from the direction of the axis A of the pair of guide holes 2, the distance between the center line segment C and the boundary ridge line immediately adjacent to the center line segment C is extended. A plane P formed by the inclined end surface 12c as a remaining portion of the grinding portion 8 in at least a part of a region outside the pair of guide holes 2 in the extending direction of the center line segment C in the band-shaped region 4c having a double width. A receding area 5c that is receding further than the above is formed. In this way, the MT ferrule 100c is formed.
The shape of the grinding portion 8 is not limited to the chamfered shape, and for example, both end edges of the MT ferrule 100c may be notched shapes extending along the both end edges.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention. For example, in the above-described embodiment, an example of an optical connector ferrule having a vertical end face on the end face has been described, but the present invention is not limited to this and can be applied to an optical connector ferrule without a vertical end face. ..
Further, in the above-described first to third embodiments, the mode in which the optical fiber is not inserted in the optical fiber insertion hole 2 is shown, but in the present invention, the optical fiber is inserted and fixed in the optical fiber insertion hole. Good.
Further, in the above-described fourth to sixth embodiments, an example in which the end face of the ferrule for an optical fiber is ground in a state where the optical fiber is not inserted into the optical fiber insertion hole has been described, but in the present invention, the optical fiber insertion is performed. The end face of the optical fiber ferrule may be ground with the optical fiber inserted and fixed in the hole.
The optical fiber inserted into the optical fiber insertion hole is preferably an optical fiber with a lens in which a rod-shaped refractive index distribution (Gradient Index, GRIN) lens is coaxially fused at the tip of the optical fiber.

  INDUSTRIAL APPLICABILITY The present invention is suitable for application to various ferrules for optical connectors that form a multi-fiber optical fiber connector, including an MT ferrule that forms an MPO connector.

1, 1a, 1b, 10 End face 2 Guide hole 3 Optical fiber insertion hole 4, 4a, 4b Band-shaped area 5, 5a, 5b Receding area 6, 6a, 6b Bonding end surface 7 Receding portion 8 Grinding portion 11, 11a, 11b Vertical end surface 12, 12a, 12b inclined end face 13, 13a, 13b first boundary ridge line 41 outer region 100, 100a, 100b, 200, 300 MT ferrule A guide hole axis C center line segment

Claims (10)

An optical connector having an end face facing the mating ferrule for an optical connector, a pair of guide holes being opened in the end face, and optical fiber insertion holes being arranged between the openings of the pair of guide holes in the end face. A ferrule for
The end face has an inclined end face in which the optical fiber insertion hole is open and which is inclined with respect to the axis of the pair of guide holes,
At least one side of the inclined end surface on both sides of a center line segment connecting the opening centers of the pair of guide holes is defined by a boundary ridge line parallel to the center line segment,
A strip having a width that is twice the distance between the center line segment and the boundary ridge line closest to the center line segment and extends with the center line segment as the center line when viewed from the axial direction of the pair of guide holes. Among the regions, at least a part of the region outside the pair of guide holes in the extending direction of the center line segment has a receding region receding from a plane formed by the inclined end face, for an optical connector. Ferrule. The end surface has a vertical end surface orthogonal to the axis of the pair of guide holes,
The ferrule for an optical connector according to claim 1, wherein the closest boundary ridge line is a first boundary ridge line that forms a boundary between the vertical end surface and the inclined end surface. The distance from the edge of the vertical end face on the side opposite to the first boundary ridge to the first boundary ridge is longer than 0.8 mm, and is more than the distance from the edge to the opening of the optical fiber insertion hole. The ferrule for an optical connector according to claim 2, which is also short. The end surface has a vertical end surface orthogonal to the axis of the pair of guide holes,
A first boundary ridgeline forming a boundary between the vertical end surface and the inclined end surface,
The optical connector according to claim 2 or 3, wherein the first boundary ridgeline is in contact with the pair of guide holes, or an extension line of the first boundary ridgeline crosses the pair of guide holes. For ferrule. The end surface has a receding part receding from a plane formed by the inclined end surface on the opposite side of the first boundary ridgeline with the center line segment interposed therebetween.
The ferrule for an optical connector according to claim 1, wherein the closest boundary ridge line is a second boundary ridge line that forms a boundary between the inclined end surface and the receding portion. The ferrule for an optical connector according to claim 5, wherein the second boundary ridge line is in contact with the pair of guide holes, or an extension line of the second boundary ridge line crosses the pair of guide holes. .. An optical connector having an end face facing the mating ferrule for an optical connector, a pair of guide holes being opened in the end face, and optical fiber insertion holes being arranged between the openings of the pair of guide holes in the end face. A ferrule processing method for an optical connector for processing a ferrule for
By grinding the end face, the optical fiber insertion hole is opened, inclined with respect to the axis of the pair of guide holes, and at least on both sides sandwiching a center line segment connecting the opening centers of the pair of guide holes. An inclined end face forming step of forming an inclined end face defined on one side by a boundary ridge line parallel to the center line segment;
A band-shaped region extending from the center line segment as a center line and having a width twice the distance between the center line segment and a boundary ridge line closest to the center line segment when viewed from the axial direction of the pair of guide holes. Of these, a retreat region forming step of forming a retreat region retreated from the plane formed by the inclined end surface by grinding at least a part of the region outside the pair of guide holes in the extending direction of the center line segment,
A ferrule processing method for an optical connector, comprising: In the stage before the inclined end face forming step, the ferrule for optical connector has, on the end face, a vertical end face orthogonal to the axis of the pair of guide holes,
In the inclined end face forming step, a first boundary ridge line is formed as the closest boundary ridge line at a boundary between the vertical end face and the inclined end face,
8. The retreat region is formed by grinding a region of the first boundary ridgeline including a ridgeline portion outside the pair of guide holes in the retreat region formation step. Ferrule processing method for optical connector. In the stage before the inclined end face forming step, the ferrule for optical connector has, on the end face, a vertical end face orthogonal to the axis of the pair of guide holes,
In the inclined end face forming step, a first boundary ridge line forming a boundary ridge line between the vertical end face and the inclined end face is formed,
Between the inclined end face forming step and the receding region forming step, a receding portion receding from a plane formed by the inclined end surface is provided on the opposite side of the first boundary ridge line across the center line segment of the end surface. Has a receding part forming step of forming,
In the receding part forming step, a second boundary ridge line is formed as the nearest boundary ridge line at the boundary between the inclined end surface and the receding part,
8. The retreat region is formed by grinding a region of the second boundary ridgeline that includes a ridgeline portion outside the openings of the pair of guide holes in the retreat region formation step. Ferrule processing method for optical connector. An optical connector having an end face facing the mating ferrule for an optical connector, a pair of guide holes being opened in the end face, and optical fiber insertion holes being arranged between the openings of the pair of guide holes in the end face. A ferrule processing method for an optical connector for processing a ferrule for
Of the end faces of the ferrule for an optical connector, at least a part of a region outside the extending direction of a center line connecting the center of the openings of the pair of guide holes, rather than the openings of the pair of guide holes, is ground and ground. A grinding portion forming step of forming a portion,
At least one side on both sides of the center line segment sandwiched by grinding the end faces and inclined with respect to the axis of the pair of guide holes is defined by a boundary ridge line parallel to the center line segment. An inclined end face forming step of forming an inclined end face,
Have
In the inclined end face forming step, when viewed from the axial direction of the pair of guide holes, the distance between the center line segment and the boundary ridge line immediately adjacent to the center line segment that extends around the center line segment is 2 Of the strip-shaped region having a doubled width, at least a part of the region outside the pair of guide holes in the extending direction of the center line segment recedes from the plane formed by the inclined end face as the remaining portion of the grinding portion. Forming a retreat region, which is characterized in that a ferrule processing method for an optical connector.