JPH08262274A - Structure for aligning optical fibers - Google Patents

Abstract

PURPOSE: To surely obtain an alignment state with good accuracy by arranging plural bar members to a cylindrical block body in the state of bringing their respective peripheral surfaces into contact with each other and inserting the coated fibers of optical fiber cables into the gap parts thereof. CONSTITUTION: Each bar member 32 is formed into a round bar shape and consists of straight part 32a having a circular section uniform by the prescribed length from one end and a tapered part 32b inclining in a direction where the diameter decreases gradually. The end faces on the straight part 32a side of the bar members 32 are aligned to be made flush with the one end side of the block body 31 at the time of building the bar members 32 into the block body 31. In addition, the peripheral surfaces of the straight parts 32a of the adjacent bar members 32 and the peripheral surfaces of the straight parts 32a and the inside wall surfaces of the housing holes are brought into contact with each other and the bar members 32 are built by the same number each in parallel in two upper and lower stages into housing holes 31a. The gaps for insertion of the coated optical fibers and guide parts for the same are, therefore, formed respectively. The coated fibers of the optical fiber cable are, thereupon, inserted into the gap parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an optical communication device or the like,
The present invention relates to an alignment structure of an optical fiber terminal for collectively connecting a plurality of optical fibers to an optical element or another optical fiber.

[0002]

2. Description of the Related Art In an optical communication device or the like, in order to collectively connect a plurality of optical fibers to corresponding optical elements or optical fibers, it is necessary to accurately align and fix terminal portions of the plurality of optical fibers at a predetermined pitch. Desired.

Conventionally, as an alignment structure of this type of optical fiber, for example, the structure shown in FIG. 10 is well known. In the figure, the alignment structure 1 of the optical fibers is a guide plate 11.
And a cover plate 12 superposed on the guide plate 11. The guide plate 11 is formed of glass, ceramic, silicon, or a metal material into a rectangular plate shape, and has a plurality of groove portions 11a (parallel to the illustrated example) extending in parallel to each other from one end to the other end in the longitudinal direction. Then 3)
It is provided. The groove portion 11a has a pair of groove surfaces 11b and 11b that form a predetermined angle in a V shape in a cross section perpendicular to the extending direction.
b. The cover plate 12 is formed of glass, ceramic, silicon, or a metal material into a flat plate shape having the same plate area as the guide plate 11.

On the other hand, in the optical fiber cable 2 aligned by the above-described alignment structure, the coating of the terminal portion is removed and the core 21a of the optical fiber of a predetermined length is exposed as shown in the figure.

Next, in order to align a plurality of optical fiber cables 2 using the above-described optical fiber alignment structure 1, first, the optical fibers 21a are arranged in the plurality of groove portions 11a of the guide plate 11. To do. Next, an adhesive is applied to the guide plate 11 in a state where the optical fiber core wires 21a are arranged, and then the cover plate is placed on the guide plate 11 while preventing the optical fiber core wires 21a from protruding from the groove portion 11a. 12 is placed, and the core wire 21a of each optical fiber is inserted into the groove 1
Press into 1a. As a result, the cores 21a of the respective optical fibers are fixed together with the guide plate 11 and the cover plate 12 with an adhesive while being aligned between the guide plate 11 and the cover plate 12 by the groove 11a.

[0006]

In the conventional optical fiber alignment structure 1, the cover plate 1 is provided on the guide plate 11.
Until the two are superposed, the optical fiber core wire 21a is not regulated upward, and therefore, the optical fiber core wire 21a may be protruded from the groove portion 11a during the work. Therefore, in order to prevent the optical fiber core wire 21a from protruding from the groove portion 11a, it is necessary to perform the work while pressing the optical fiber core wire 21a toward the groove portion 11a with a finger or the like, which is extremely poor in workability. It was

The present invention has been made in order to solve the above-mentioned drawbacks, and provides an optical fiber alignment structure that facilitates alignment work of the optical fibers and provides an accurate alignment state. To provide.

[0008]

In an optical fiber alignment structure in which the cores of a plurality of optical fiber terminals are aligned, a cylindrical block main body with both ends open, and a predetermined arrangement in the block main body are held. A plurality of rod members having a uniform circular cross-section, and the core of the optical fiber is inserted into a gap formed between the peripheral surface of the adjacent rod members or the inner surface of the block body. To align.

With the above structure, when the core of the optical fiber is inserted into the gap, the core of the optical fiber is aligned with the peripheral surface of the rod being restricted. For this reason, unlike the conventional example, it is not necessary to hold the optical fiber core wire with fingers so that it does not protrude from the groove portion, and it is possible to obtain a highly accurate aligned state and to improve work efficiency. An optical fiber alignment structure is obtained.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 (a) is a perspective view showing the entire alignment structure of the present invention, FIG. 1 (b) is a perspective view of a bar member that is one component of the alignment structure, and FIG. 2 is a projection view of the alignment structure. (A)
Is a front view, (b) is a left side view, (c) is a plan view, (d)
Is a right side view. In the figure, an optical fiber alignment structure 3 of the present invention includes a cylindrical block body 31 and a block body 3.
It is composed of a plurality of rod members 32 housed in one.

The rod member 32 is formed of glass, ceramic, plastic, metal material or the like into a round rod shape as shown in FIG. 1B, and has a straight line portion having a uniform circular cross section for a predetermined length from one end. 32a and straight part 3
The taper portion 32b is inclined in a direction in which the diameter gradually decreases from 2a toward the other end. The block body 31 is made of glass, ceramic, plastic, or a metal material, and is formed in a rectangular tube shape with both ends open. The block body 31 has a rectangular cross section for accommodating the rod member 32.
1a is provided in the axial direction. The axial dimension of the block body 31 is set to be slightly larger than the length dimension of the rod member 32, and the cross-sectional dimension of the accommodating hole 31a is such that the plurality of rod members 32 are arranged vertically and horizontally (in this embodiment, vertically). 2 rows 5 rows),
The dimensions are set so that the linear portions 32a can be just accommodated in a state where the peripheral surfaces thereof are in contact with each other.

Next, when the rod member 32 is incorporated into the block body 31 described above, the rod member 32 is aligned so that the end surface of the straight portion 32a side is flush with the one end side of the block body 31 and adjacent to each other. The peripheral surfaces of the linear portions 32a of the rod member 32 to be in contact with each other, and the peripheral surface of the linear portion 32a and the inner wall surface of the accommodation hole are brought into contact with each other, and the same number is provided in the accommodation hole 31a in upper and lower two stages (five in each example). ) Installed in parallel. Then
Since the block body 31 and the bar member 32 are integrally joined,
Means such as adhesive or soldering are used depending on the materials of both parts. As described above, by arranging the plurality of rod members 32 in the block main body 31, the peripheral portion of the straight portions 32a of the four adjacent rod members 32 causes the gap 3a for inserting the optical fiber core wire to be tapered. The guide portions 3b are respectively formed by the portions 32b. As shown in the drawing, the void 3a is a space surrounded by the peripheral surface portions of the linear portions 32a of the four adjacent bar members 32. Further, the guide portion 3b is continuous from the void portion 3a, and is gradually expanded to the other end side of the block body 31 by the slope of the taper portion 32b.

In the above-mentioned void portion 3a, the inscribed circle contacting the peripheral surfaces of the straight line portions 32a of the four adjacent rod members 32 is the same as or slightly larger than the outer diameter of the core wire 21a of the optical fiber. The diameter of the straight portion 32a of the rod member 32 is determined.

FIG. 3 shows the optical fiber core wire 2 in the cavity 3a.
It is an enlarged view of the state in which 1a is inserted, and the core wire 21a of the optical fiber is inscribed in the peripheral surface portions of the linear portions 32a of the four rod members 32 forming the voids 3a, respectively. In the figure, the radius of the straight portion 32a of the rod member 32 is represented by R
₁ , when the radius of the optical fiber core wire 21a is r ₁ ,
From the figure, the relational expression between R ₁ and r ₁ is (R ₁ + r ₁ ) ² = R ₁
² + R ₁ ² and from this

[0015]

[Equation 1]

[0016] The rod member 3 forming the void 3a according to the diameter of the core of the optical fiber aligned from this equation.
Two diameter dimensions can be set.

Next, when aligning the optical fibers 21a by the optical fiber aligning structure 3 of the present invention, as shown in FIG. 4, a guide portion 3b opened to the other end side of the block body 31.
Position the optical fiber core wire 21a toward the
A plurality of optical fiber core wires 21a are simultaneously (or one by one) inserted into the corresponding guide portions 3b. As a result, the core 21a of the optical fiber is guided by the guide portion 3b, and the space 3
reach a. Thereafter, the core wire 21a of the optical fiber is further pushed toward the one end side of the block body 31, until the end surface of the core wire 21a of the optical fiber and the end surface of the linear portion 32a of the rod member 32 are flush with each other. Optical fiber core wire 21
a is inserted along the peripheral surface of the straight portion 32a. As a result, the cores 21a of the respective optical fibers are aligned in a straight line within the block main body 31 at a constant pitch without being loosened by being regulated by the peripheral surface of the linear portion 32a of the rod member 32 on all four sides. FIG. 5 shows this state.

After the core wires 21a of the optical fibers are aligned in the block body 31 as described above, the guide portion 3b is filled with an adhesive, and the core wires 21a of the optical fibers are placed in the block body 31.
Is fixed.

Next, another embodiment of the present invention will be described with reference to FIGS. In another embodiment shown in FIG. 6, the rod members 32 are arranged side by side in the accommodating holes 41a of the block main body 41, and the peripheral surface of the adjacent rod members 32 and the inner wall surface of the lower side of the accommodating holes 41a. Thus, the void portion 4a for inserting and aligning the core wire 21a of the optical fiber is formed.

FIG. 7 shows the optical fiber core 21 in the gap 4a.
It shows a state in which a is inscribed, and in FIG.
2 is R ₂ , and the radius of the optical fiber core wire 21a is r ₂
Then, from the figure, (R ₂ + r ₂ ) ² = R ₂ ² + (R ₂ −
r ₂ ) ² , and the relational expression of R ₂ = 4r ₂ is obtained. The diameter of the core wire 21a of the optical fiber aligned by this equation sets the diameter of the rod member 32 and the housing hole 41a of the block body 41 that houses the rod member 32.

Next, in another embodiment shown in FIG. 8, the rod member 32 is not inscribed in the upper inner wall surface of the accommodation hole 51a of the block main body 51, but is arranged in parallel in only one step, so that the accommodation hole 51a A void 5a is formed between the upper inner wall surface and the peripheral surface of the rod member 32. The optical fiber core wire 21a is inserted into the space 5a, and the optical fiber core wire 21a is inscribed and aligned between the peripheral surfaces of the adjacent rod members 32 and the upper inner wall surface of the block body 51. Next, FIG. 9 shows a state in which the optical fiber core wire 21a is inscribed in the space 5a. In the figure, if the radius of the straight portion 32a of the rod member 32 is R ₃ , the radius of the optical fiber core wire 21a is r ₃ , and the dimension between the upper and lower inner wall surfaces of the accommodation hole 51a is h,

[0022]

[Equation 2]

A relational expression of is obtained, and from this expression, the rod member 32
The diameter of the linear portion 32a and the dimension h of the accommodation hole 51a are set. In the embodiment shown in FIG. 8, the arrangement pitch of the optical fibers 21a is freely set by making the diameter of the rod member 32 correspond to the arrangement pitch of the optical fibers 21a.

[0024]

As described above, in the optical fiber alignment structure of the present invention, a plurality of rod members each having a tapered one end and a circular cross section are arranged in a cylindrical block body with their peripheral surfaces being in contact with each other. Thus, a gap is formed between the peripheral surfaces of the adjacent rod members, and the core of the optical fiber is inserted and aligned in the gap with the tapered portion as a guide. For this reason, the optical fiber core wire can be reliably and accurately aligned without the risk of protruding from the void during assembly work, and the optical fiber alignment with improved work efficiency compared to the conventional example. Structure is provided.

[Brief description of drawings]

1A and 1B are examples of an optical fiber alignment structure according to the present invention, in which FIG. 1A is a perspective view showing the alignment structure as a whole, and FIG. 1B is a perspective view of a rod member that is a component of the alignment structure.

FIG. 2 is a projection view of an optical fiber alignment structure according to the present invention, in which (a) is a front view, (b) is a left side view, (c) is a plan view, and (d) is a right side view.

FIG. 3 is an enlarged view of a main part of the optical fiber alignment structure shown in FIG.

FIG. 4 is an explanatory view showing an example of use of the optical fiber alignment structure shown in FIG.

5 is a perspective view showing a state in which the optical fibers are aligned by the optical fiber alignment structure shown in FIG.

FIG. 6 is a perspective view showing another embodiment of the present invention.

7 is an enlarged view of a main part of the optical fiber alignment structure shown in FIG.

FIG. 8 is a perspective view showing another embodiment of the present invention.

9 is an enlarged view of a main part of the optical fiber alignment structure shown in FIG.

FIG. 10 is an exploded perspective view showing an alignment structure of optical fibers according to a conventional example.

[Explanation of symbols]

 21a Optical fiber core wire 3a Air gap 31 Block body 32 Bar member

Claims (2)

[Claims] 1. In an optical fiber alignment structure for aligning cores of a plurality of optical fiber end portions, a cylindrical block main body having both ends open, and peripheral surfaces of the block main body contacting each other in a predetermined arrangement in the block main body. And a plurality of rod members having a uniform circular cross section, which are housed and held in the gap, formed between the peripheral faces of the adjacent rod members or the inner surface of the block body, and the optical fiber core wire. An optical fiber alignment structure characterized by inserting and aligning. 2. One end of the rod member is formed in a tapered shape,
The optical fiber alignment structure according to claim 1, wherein a guide portion for inserting a core wire of the optical fiber is inserted into the void portion.