JP3368780B2 - Fiber array for optical waveguide and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical waveguide fiber array for connecting an optical fiber and an optical waveguide and a method for manufacturing the same.

[0002]

2. Description of the Related Art FIG. 4 is a diffusion exploded view of a conventional optical waveguide fiber array, FIG. 5 is a process diagram showing a method of manufacturing a conventional optical waveguide fiber array, and FIG. 5 is a front view of the fiber array for optical waveguide of FIG.
5B is a side view of FIG. 5A, FIG. 5C is a plan view of the assembled optical waveguide fiber array, and FIG. 5D is FIG.
5C is a front view and FIG. 5E is a side view of FIG. 5D.

In FIG. 4, an optical fiber 1 for connecting to an optical waveguide device (not shown) is a V-grooved surface 2 of a substrate 2.
The optical fibers 1 on the V-shaped grooves 3 are covered with an upper plate 4, which are fixed to the arrayed V-shaped grooves 3 formed on a by adhesive. The core of the optical fiber 1 exposed on the end face of the optical waveguide fiber array and the core of the optical waveguide (not shown) are connected. The length L of the substrate 2 is 10 mm
Then, the V-groove processed surface 2a is 0.3 mm smaller than the non-processed surface 2b of the substrate 2.
The thickness of the V-grooved surface 2a is 5 mm. The length Lu of the upper plate 4 is 5 mm, which is equal to the length of the V-grooved surface 2a.

A method of manufacturing such an optical waveguide fiber array will be described with reference to FIG.

First, a substrate 2 having a V-shaped groove 3 is prepared, an acrylate-based UV-curable adhesive 5 is applied to the V-shaped groove 3 and the V-grooved surface 2a, and the exposed portion 1a of the optical fiber 1 is aligned. To do. The gap between the V groove 3 and the optical fiber 1 is filled with an acrylate ultraviolet curing adhesive 5. The optical fiber 1 is covered with the upper plate 4 from above the V groove 3, and the exposed portion of the optical fiber 1 is covered with an acrylate-based ultraviolet curing adhesive 6 (FIGS. 5A and 5B).

Acrylate UV-curable adhesive 5, 6
The optical fiber 1 and the upper plate 4 are fixed to the substrate 2 by irradiating the substrate with ultraviolet rays to cure the fiber array for the optical waveguide. In this fiber array for an optical waveguide, the exposed portion 1a of the optical fiber 1 is fixed and protected by an acrylate-based ultraviolet curing adhesive 6 (FIG. 5).
(C), (d), (e)).

[0007]

However, in the above-mentioned conventional optical waveguide fiber array, when the substrate 2 expands and contracts in the longitudinal direction due to temperature change, stress concentrates at the root of the exposed portion 1a of the optical fiber 1. There was a problem that bending and light loss would increase.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and provide an optical waveguide fiber array in which stress concentration at the root of the exposed portion of the optical fiber is prevented and a method for manufacturing the same.

[0009]

In order to achieve the above object, the present invention provides an optical fiber in which an optical fiber for connecting to an optical waveguide device is fixed to an array-shaped groove formed on a substrate with an adhesive. In the waveguide fiber array, except for the exposed part of the optical fiber and the part covered by the upper plate,
Ri root with a covering with an organic adhesive softer than acrylate based UV curable adhesive, a length covering at organic adhesive soft are covered with the upper plate a exposed portion of the optical fiber
It is characterized in that it is 2 to 3 mm from the root near the upper plate of the portion other than the above .

In addition to the above structure, the present invention provides an organic system harder than the soft organic adhesive except for the root of the optical fiber exposed portion covered with the upper plate, which is closer to the upper plate. It is preferable to fix the optical fiber with an adhesive.

A method of manufacturing a fiber array for an optical waveguide according to the present invention comprises an optical fiber for connecting to an optical waveguide element,
In a method for manufacturing an optical waveguide fiber array in which an array-shaped groove formed on a substrate is fixed with an adhesive, in the exposed portion of the optical fiber, which is not covered by the upper plate,
The root of the plate side is adhered and fixed so that it is covered with an organic adhesive that is softer than the acrylate ultraviolet curing adhesive, and the length covered with the soft organic adhesive is the exposed portion of the optical fiber and the upper plate. It is characterized in that it is 2 to 3 mm from the root near the upper plate of the portion other than the portion covered with.

According to the present invention, the exposed portion of the optical fiber is
By covering the base near the upper plate other than the part covered with the upper plate with an organic adhesive that is softer than the acrylate UV-curable adhesive for 2 to 3 mm, the substrate expands and contracts due to temperature changes. However, since the optical fiber expands and contracts together with the soft organic adhesive to relax the stress, the optical fiber is not bent at the root of the exposed portion, and an increase in optical loss due to stress concentration is prevented.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a diffusion exploded view showing an embodiment of a fiber array for an optical waveguide of the present invention. FIG. 2 is a process diagram showing a method for manufacturing the optical waveguide fiber array shown in FIG. 1, FIG. 2 is a front view of the optical waveguide fiber array before assembly, and FIG. 2B is a side view of FIG. Figure, Figure 2 (c)
Is a plan view of the fiber array for optical waveguide after assembly, FIG.
2D is a front view of FIG. 2C, and FIG. 2E is FIG. 2D.
FIG. The same reference numerals are used for the same members as those in the conventional example shown in FIGS. 4 and 5.

In FIG. 1, a plurality of (but not limited to, two in the figure) optical fibers 1 for connecting to an optical waveguide element are arrayed on a substrate 2 (two in the figure). It is fixed to each of the V grooves 3 of (but is not limited to, but may be larger than the number of optical fibers) with an adhesive, and the optical fibers on the V grooves 3 are covered with the upper plate 4. The core of the optical fiber 1 exposed on the end face of the optical waveguide fiber array and the core of the optical waveguide (not shown) are connected. The length L of the substrate 2 is 10 mm, the V-grooved surface 2a is 0.3 mm thicker than the non-machined surface 2b, and the V-grooved surface 2a has a length of 5 mm. The length Lu of the upper plate 4 is 5 mm, which is equal to the length of the V-grooved surface 2a.

A method of manufacturing such a fiber array for an optical waveguide will be described with reference to FIG.

A substrate 2 having two parallel V-grooves 3 is prepared, and an acrylate-based UV-curable adhesive 5 is applied to the V-grooves 3 and the V-groove processing surface 2a to expose the exposed portion 1 of the optical fiber 1.
Arrange a. At this time, an acrylate-based ultraviolet curing adhesive 5 is filled in the gap between the V groove 3 and the optical fiber 1. The optical fiber 1 is covered with the upper plate 4 from above the V groove 3, and the root of the exposed portion 1a of the optical fiber 1 is softer than an acrylate-based UV-curable adhesive, such as an organic adhesive, for example, a silicone-based UV-curable adhesive. 7, and other exposed portions of the optical fiber are covered with an organic adhesive that is harder than the soft organic adhesive, for example, an acrylate-based UV-curable adhesive 6. That is, the adhesive covering the exposed portion 1a of the optical fiber 1 has a two-layer structure of a soft adhesive and a hard adhesive. The length of the silicone-based ultraviolet curable adhesive 7 that covers the exposed portion 1a of the optical fiber 1 is preferably 2 to 3 mm (FIGS. 2A and 2B).

Acrylate UV-curable adhesives 5, 6
By irradiating the silicone-based ultraviolet-curable adhesive 7 with ultraviolet rays to cure it, the optical fiber 1 and the upper plate 4 are fixed to the substrate 2, and the optical waveguide fiber array is completed. In this optical waveguide fiber array, the optical fiber 1 is fixed and protected by an acrylate-based UV curable adhesive 6 and a silicone-based UV curable adhesive 7 at the exposed portion 1a of the optical fiber 1 ( Figure 2
(C), (d), (e)).

In the fiber array for an optical waveguide thus obtained, the base of the exposed portion 1a of the optical fiber 1 is covered with the soft organic adhesive 7 so that the substrate 2 expands and contracts due to temperature change or the like. However, since the optical fiber 1 expands and contracts together with the soft organic adhesive 7 to relieve the stress, the optical fiber 1 is not bent at the root of the exposed portion 1a, and an increase in optical loss due to stress concentration is prevented. To be done.

FIG. 3 is a diagram comparing the loss variation width of the optical waveguide fiber array of the present invention with the loss variation width of the conventional optical waveguide fiber array. The horizontal axis represents the loss variation width and the vertical axis represents the loss variation width. Shows the frequency.

When a temperature change of −40 ° C. to 80 ° C. was applied, the average loss variation amount was 0.20 dB in the case of the conventional example, while the average loss variation amount was 0.20 dB in the case of the present invention.
It could be improved to 11 dB.

[0022]

In summary, according to the present invention, the following excellent effects are exhibited.

The exposed portion of the optical fiber, which is covered by the upper plate
By covering the base near the upper plate with a soft organic adhesive for 2 to 3 mm other than the open part , stress concentration on the root of the exposed part of the optical fiber is prevented, and the optical fiber bends due to the stress concentration. An increase in light loss is prevented.

[Brief description of drawings]

FIG. 1 is a diffusion exploded view showing an embodiment of a fiber array for an optical waveguide of the present invention.

FIG. 2 is a process drawing showing a method for manufacturing the fiber array for optical waveguides shown in FIG.

FIG. 3 is a diagram comparing the loss variation width of the optical waveguide fiber array of the present invention with the loss variation width of the conventional optical waveguide fiber array.

FIG. 4 is a diffusion exploded view of a conventional fiber array for an optical waveguide.

FIG. 5 is a process chart showing a conventional method for manufacturing a fiber array for an optical waveguide.

[Explanation of symbols]

1 Optical Fiber 1a Exposed Part 2 Substrate 3 Groove (V Groove) 4 Upper Plate 6 Hard Organic Adhesive (Acrylate UV Curing Adhesive) 7 Soft Organic Adhesive (Silicone UV Curing Adhesive)

Claims (3)

(57) [Claims] 1. An optical waveguide fiber array in which an optical fiber for connecting to an optical waveguide element is fixed to an array-shaped groove formed on a substrate with an adhesive, and the exposed portion of the optical fiber is Of the part other than the part covered by the upper plate,
The base near the upper plate is covered with an organic adhesive that is softer than the acrylate UV-curable adhesive, and the length covered with the soft organic adhesive is the exposed portion of the optical fiber and the upper plate.
2 to 3 from the root near the upper plate except the part covered with
mm is a fiber array for optical waveguides. 2. The exposed portion of the optical fiber , which is covered with an upper plate.
The fiber array for an optical waveguide according to claim 1, wherein the optical fiber is fixed with an organic adhesive that is harder than the soft organic adhesive, except for the roots near the upper plate of the portion other than the cut portion . 3. A method of manufacturing a fiber array for an optical waveguide, wherein an optical fiber for connecting to an optical waveguide element is fixed to an array-shaped groove formed on a substrate with an adhesive, in an exposed portion of the optical fiber. Except for the part covered by the upper plate
Among them, the root of the upper plate side is adhered and fixed so as to be covered with an organic adhesive that is softer than the acrylate ultraviolet curing adhesive, and the length covered with the soft organic adhesive has an exposed portion of the optical fiber. And out of the parts covered by the upper plate
A method for manufacturing an optical waveguide fiber array, characterized in that it is 2 to 3 mm from the root of the upper plate side .