JPS6356616A - Method for fixing optical fiber in optical fiber guide groove - Google Patents

Abstract

PURPOSE:To facilitate the fixation of an optical fiber by providing an adhesive for optical fiber fixation as an adhesive layer in a member previously. CONSTITUTION:A press plate 3 is mounted on a substrate 1 which has optical fiber grooves 2 formed in its top surface across a hot-melt adhesive layer 4 and they are sandwiched entirely and clamped by elastic clips 5. In this state, the optical fiber A is inserted into a guide groove 2 and the whole body is heated. The hot-melt adhesive 4 decreases in viscosity by being heated and flows in the gap 6 between the optical fiber A and optical fiber groove 2 through the pressing operation of the elastic clips 5. Then, the whole body is cooled and the adhesive 4' is caked to fix the optical fiber A in the guide groove 2.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for fixing an optical fiber to an optical fiber guide groove of an optical connector, a coupling member, etc. that realizes the connection of optical fibers in optical communication.

(Prior art and problem to be solved) When optical fibers are connected using an optical connector or a precision sleeve, it is necessary to fix the optical fibers to a positioning member, but in these cases adhesive Generally, an adhesive is injected into the optical fiber guide hole, the optical fiber is inserted into the optical fiber guide hole, and the adhesive is cured and fixed.

Figure 3 is a top view of the interior of a conventional optical connector with the optical fiber positioned, where (A) is the optical fiber that has been positioned and fixed, (B) is the optical fiber core, and GO is for inserting the guide pin. This is a guide pin hole CD, and two guide pins are inserted into the guide pin hole CD to realize the connection of the optical connectors 00 facing each other.

FIG. 4(a) is a front view of the coupling end of such an optical connector OG, and FIG.
01 is an optical fiber core! 9 (B) is the hole that holds it.

However, as shown in the same figure (c), the optical fiber (A)
is inserted into the optical fiber guide 60'lJ,
It is fixed with adhesive C41.

However, such fixing of the optical fiber (A) to the optical fiber guide 6021 requires a work step of injecting adhesive 0@ into the optical fiber guide hole Ob. In particular, it is extremely difficult work to fix a large number of optical fibers to a multi-fiber optical connector or multi-fiber precision sleeve with adhesive at a cable installation site, and the on-site bone is difficult to connect to a multi-fiber optical connector or precision sleeve. FIG. 3 is a cross-sectional front view of the assembled state of the members, which is one of the work steps that poses an obstacle. Since the optical fiber fixing method of the present invention can be applied to various types of optical connectors and coupling members such as precision sleeves, only the most important fixing portion of the optical fiber is shown in the figure.

In the drawing, (1) is a substrate with an optical fiber guide groove (2) formed on its upper surface, and a holding plate (J) is placed on top of the substrate (0) via a hot-melt adhesive layer (4). Ori,
These are all sandwiched together and clamped under pressure by elastic clips (2).

The above-mentioned pressure clamp may use a pressure jig for the removal of the elastic clip (1), in which a part of the component and the fiber (A) are inserted into the optical fiber guide groove (2) in advance, and the whole is heated.

When heated, the hot melt adhesive (4) becomes low in viscosity and flows into the gap (■) between the optical fiber (A) and the optical fiber guide groove (■) as shown in Figure 2 (0) by the pressure action of the elastic clip (■), and the entire By cooling, the adhesive (4') solidifies,
Fix the optical fiber (A) in the optical fiber guide groove (■).

As described above, in the optical fiber fixing method of the present invention, there is no need to inject adhesive into the optical fiber guide groove at the site, but by preparing a presser plate (■) coated with the adhesive layer (2) in advance. Just leave it there.

It should be noted that the fixing method of the present invention can of course be applied to fixing the optical fiber core part using the same principle.
1) was ground with a V-shaped grindstone to create an 8-fiber optical fiber guide groove (2) as shown in FIG. On the other hand, the holding plate (■) is made of transparent quartz glass so that the butt state of the internal optical fiber (A) can be seen, and on its - side, a similarly transparent hot-melt adhesive layer (4) with a thickness of 200 μm is applied.
pre-coated. Then, the substrate (1) and the presser plate (3) were clamped using elastic clips (2).

Hot melt bone cement by clamping above (Φ
However, taking this into consideration, the optical fiber guide groove ■ was machined so that it became a V-shaped optical fiber guide groove ■ corresponding to the 125 μmφ optical fiber (A) in this lamp state. .

In this state, 8.
The core optical fiber (A) was inserted, and the whole was placed on a heater and heated to about 100° C. to reduce the viscosity of the hot melt adhesive (4), and then cooled. During this process, a portion of the hot melt adhesive flowed into the gap (6) between the optical fiber (A) and the optical fiber guide groove (2) as shown in FIG.

It had a tensile strength of

In addition, we made an 8-core 711 dense sleeve using this fixing method and checked the temperature change in coupling loss in the range of -20°C to +60°C, but the coupling loss change was less than ±O, 1 dB, which is normal. It was confirmed that this method was comparable to the adhesive fixing method used in the previous method, and there was no problem in practical use.

(Effects of the Invention) According to the double optical fiber fixing method of the present invention, the following effects are achieved.

■Since the adhesive for fixing the optical fiber is provided in advance as an adhesive layer within the member, the troublesome work of injecting the adhesive into the optical fiber guide hole at the installation site etc. is eliminated.

(2) By heating the substrate and the presser plate while they are clamped under pressure, pressure is applied to the hot melt adhesive layer, allowing the adhesive to quickly flow into the optical fiber guide groove.

■ By attaching an elastic clip to the component in advance (by inserting the optical fiber into the optical fiber guide groove and heating and cooling it, pressure is constantly applied and promotes the inflow of the hot melt coupling agent. , the hot melt adhesive naturally flows into the optical fiber guide 1.■ and easily fixes the optical fiber.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional front view of assembled members for realizing the optical fiber fixing method of the present invention, and FIGS. 2(a) and 2(b) are explanatory diagrams of the fixing method of the present invention. Fig. 3 is a top view showing the inside of an example of a conventional optical connector, and Figs. 4 (a) to (c) are explanatory diagrams of a conventional optical connector soot cover. Front view, same figure (-
J) is a longitudinal side view, and FIG. A: Optical fiber, B: Optical fiber, ■...
- Substrate, 2... Optical fiber guide groove, 3... Holding plate, 4... Adhesive layer, 5... Elastic clip. Folding screen 1 Illustration 2 Illustration 3 Illustration 4 Illustration

Claims (3)

[Claims] (1) A holding plate is bonded to a substrate with an optical fiber guide groove formed on the top surface with an adhesive layer interposed, an optical fiber is inserted into the optical fiber guide groove, and the whole is clamped under pressure. An optical fiber guide groove characterized in that the adhesive is heated to lower its viscosity and flow into the optical fiber guide groove, and the adhesive is solidified by lowering the temperature to fix the optical fiber in the optical fiber guide groove. Optical fiber fixing method. (2) A method for fixing an optical fiber to an optical fiber guide groove according to claim 1, wherein the adhesive is a hot melt adhesive. (3) The method for fixing an optical fiber to an optical fiber guide groove according to claim 1, wherein the pressure clamp sandwiches the substrate and the holding plate in a sandwich-like manner using an elastic clip.