JP2002207139A - Optical fiber connecting part and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple and practical connecting part, with which optical transmission loss is reduced in connecting an optical fiber to an optical component, and also to provide its manufacturing method. SOLUTION: An optical fiber is mounted at the tip end with a soft light transmissive body having stickiness on one side, and is connected to an optical component. The connecting part is used with the sticky side in close contact with the optical fiber, and is preferably structured with the other side protruding outward from the center. The refractive index of each of the light transmissive body and a sticking body is preferably within ±0.05 to that of the optical fiber. It is also desirable that the light transmissive body is made of a silicone resin, acrylic resin, epoxy resin, thermoplastic elastomer resin, or derivative of these resins all having a JIS (A type) hardness 50 or below. The manufacturing method is by drawing or filling for example.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical connecting part of an optical fiber, and more particularly to a practical technique for reducing a loss during optical transmission.

[0002]

2. Description of the Related Art The optical transmission efficiency of an optical transmission line using an optical fiber depends on the connection loss at the optical connection between the optical fiber and other optical components (optical fiber, optical semiconductor, etc.) in the optical transmission line. Greatly affected. The causes of connection loss in these connections include those that contribute to the positioning accuracy and the end face state of the optical fiber.

In order to effectively eliminate these causes, it is necessary to increase the precision of the connecting device with a complicated structure or to perform advanced polishing treatment on the end face of the optical fiber. These greatly increase costs when connecting optical fibers, and are a major obstacle to widespread use of optical communication systems for information transfer. In order to spread the optical communication system to offices and homes, it is important to be able to easily connect the optical communication system at the same cost as conventional electric wiring, for example.

[0004] Examples of the optical semiconductor include a light emitting / receiving diode and a semiconductor laser. In general, optical semiconductors are designed with high accuracy and are often fixed to the optical device main body. Therefore, taking measures to reduce connection loss on the optical fiber side is considered effective in practical use.

The present inventors have proposed a structure in which a flexible light transmitting body is interposed in an optical connection portion in order to reduce connection loss which is a problem in optical transmission (Japanese Patent Application Laid-Open No. H10-111429, Japanese Patent Application No.
0-144718). The inventor of the present invention has made intensive studies and proposes a technique for controlling the adhesiveness of a connection component mounted on the tip of an optical fiber and improving the practicality. ADVANTAGE OF THE INVENTION According to this invention, anyone can replace | exchange an optical connection component simply and reliably in an office or a general household.

[0006]

SUMMARY OF THE INVENTION The present invention relates to an easily replaceable connecting component which can reduce optical transmission loss when connecting an optical fiber and optical components, for example, an optical fiber and an optical fiber or an optical semiconductor, and a method of manufacturing the same. It is a suggestion.

[0007]

SUMMARY OF THE INVENTION The present invention aims at reducing optical transmission loss and simplifying component replacement by mounting an adhesive flexible light transmitting component at the tip of an optical fiber.

The present invention relates to a component which is attached to the tip of an optical fiber and optically connects the optical fiber and optical components, and is a connecting component for an optical fiber having a light-transmitting adhesive layer on one side.

The present connection component is used by bringing the adhesive layer surface into close contact with the optical fiber. Any adhesive may be used as long as it is transparent and sticky. For example, commercially available silicone-based, acrylic-based, epoxy-based, and thermoplastic elastomer-based pressure-sensitive adhesives can be used. Further, a softer substance of the same kind as the light transmitting body may be used.

The opposite side of the pressure-sensitive adhesive layer has a convex structure in which the thickness decreases continuously or stepwise from the center toward the outer periphery.

The refractive index of the light transmitting member and the adhesive member is within ± 0.05 of the refractive index of the optical fiber.

The light transmitting body is at least one selected from silicone resins, acrylic resins, epoxy resins, thermoplastic elastomer resins, and derivatives of these resins having a hardness of 50 degrees or less according to JIS (A type). .

[0013] As a method of manufacturing a connecting part for an optical fiber, it is common to form a light transmitting layer and add an adhesive layer to the light transmitting layer. The raw materials for the light transmitting body are applied or filled, then solidified, and the sticky body is adhered thereto to produce. In addition, continuous production has higher productivity and is advantageous in cost.

The optical fiber connecting part of the present invention is mounted on the tip of the optical fiber. A person attaches and detaches the optical fiber by himself / herself to the connection device, and there is an advantage that a complicated connection is not required and a conventional connection device can be used.

Further, since the adhesive is adhered to the optical fiber side, it is extremely easy to replace the connecting part when the connecting part is contaminated or worn out, and can be performed by anyone in a general household.

The shape of the connecting component is preferably a disc-like shape, and a convex structure in which the thickness is reduced continuously or stepwise from the central portion toward the outer peripheral portion is preferable. This shape has the effect of releasing air bubbles at the interface during connection with the optical components, thereby reducing the connection loss.

Examples of the optical fiber include products of manufacturers such as Shin-Etsu Chemical Co., Ltd. made of quartz, Toray Co., Ltd. made of polymethyl methacrylate resin, and Asahi Glass Co., Ltd. made of fluorine resin. In addition, as optical semiconductors, Matsushita Electric Industrial,
Examples include products from domestic manufacturers such as Hamamatsu Photonics and overseas manufacturers such as Hewlett-Packard and Samsung.

The light transmitting body and the adhesive body are substantially the same as the refractive index of the optical fiber, and the refractive index of the optical fiber is ± 0.05.
It is preferred that If this difference is too large, optical transmission loss due to reflection or the like is caused. The maximum refractive index of the optical fiber is 1.55 made of polymethyl methacrylate resin, and the minimum is 1.35 made of fluorine resin.

The light transmitting body is required to be flexible, and its hardness is preferably 50 degrees or less according to JIS (A type).
It is preferably 60 degrees or less in IS (D type). If it is too hard, the adhesion at the time of connection will be insufficient and a gap will be created, resulting in loss during optical transmission. Suitable resins include silicone resins, acrylic resins, epoxy resins, elastomer resins, and derivatives thereof. Commercial products are product catalogs of Shin-Etsu Chemical, Toagosei, Nippon Kayaku, etc. You can choose more.

FIG. 1 shows an example of a connecting part according to the present invention. (1) is a front view, and (2) is a side view. a) and b) have different connection surface shapes (planar, convex). 11
Is a flexible light transmitting body, and 12 is an adhesive body. Use this connection part by attaching it to the tip of the optical fiber, and replace it if it is damaged or contaminated.

FIG. 2 shows an example of a connecting part (assembly) of the present invention. (1) is a front view, (2) is a cross-sectional view, and a light transmitting body 21, an adhesive body 22, a receiver 23, and a release film 24.
It is composed of Reference numerals 23 and 24 denote processed products of materials having good releasability from the connection parts. At the time of use, the release film is peeled off to expose the connecting parts, the tip of the optical fiber is pressed there, the connecting parts are mounted, and the optical parts are connected.

FIG. 3 shows an example (1) in which the connecting part of the present invention is mounted on an optical fiber, and an example (2) in which an optical fiber and an optical semiconductor are connected using the connecting part of the present invention (any one). Is also a cross-sectional view seen from the side in the connection direction). The connection component 30 has a light transmitting body 31 and an adhesive body 32. 35 is an optical fiber, 36 is a ferrule, 37 is an optical semiconductor, 38 is a plug, and 39 is a socket.

FIG. 4 shows an example of a method for manufacturing a connection component according to the present invention. This example is a manufacturing method corresponding to claim 7,
It mainly consists of three steps: filling 1), solidifying 2), and sticking 3). In the filling step, the light transmitting material 4
0, and solidified in the next step.
The release film 44 coated with 2 is bonded to a receiver containing the light transmitting body 41 to manufacture an assembly of connection parts of the present invention. As a matter of course, the receiver and the release film were made of a material having excellent releasability from the connection parts.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described with reference to Examples and Comparative Examples. The present invention is to reduce the connection loss during optical transmission by mounting a flexible and transparent connecting part at the tip of an optical fiber. The connecting part of the present invention was manufactured as follows.

Manufacturing method 1: Manufacturing method of connection part 1 A transparent urethane elastomer resin resin pellet as a raw material was formed into a sheet having a thickness of 1 mm using a hot roll, and the surface of this sheet was bonded with two release films. (A urethane-based adhesive is applied to one of the release films). Next, 2m from the side of the release film with adhesive
The light transmitting sheet was cut into a circle having a diameter of m (the peeling film on the opposite side was not cut). When used, the circular portion is peeled off from the adhesive side of the sheet, and the tip of the optical fiber is pressed against the connection component. By this operation, the connection component is automatically mounted on the tip of the optical fiber.

Manufacturing method 2: Manufacturing method of connecting part 2 This is a manufacturing method according to the process of FIG. A transparent silicone resin was used as a raw material for the light transmitting body and the adhesive.

[0027]

Embodiment 1 A connecting part 1 (FIG. 1, (2) -a) of the present invention is mounted on the tip of a polymethyl methacrylate resin optical fiber (Toray) having a refractive index of 1.50 as shown in FIG. ,
It connected to the transceiver using the existing SMI type connector (Daiko Electric). The connection loss at this time was 0.2 dB. The light transmitting body of the connecting part has a refractive index of 1.50, JIS
(A) 5 degree transparent urethane elastomer resin (Cosmo Instruments).

[0028]

Embodiment 2 A connecting part 2 of the present invention (FIG. 1, FIG. 1) was attached to the tip of a fluorine resin optical fiber (Asahi Glass) having a refractive index of 1.35.
(2) b) Shape) was attached and connected to the transceiver using an LC type connection device (Lucent Technologies). In this case, the light transmitting body has a refractive index of 1.43 and JI
S (A) A fluorine-modified silicone resin having a cured property of 10 degrees (Shin-Etsu Chemical Co., Ltd.) was used. The connection loss in this example was 0.2 dB.

[0029]

[Comparative Example 1] In the case of Example 1, the connection was made by a conventional method without mounting the connecting parts. In this case, the optical transmission loss at the connection was 1.9 dB. That is, it is considered that the connection loss was caused by the effect of the air layer in the gap.

[0030]

Comparative Example 2 A connection was made in the same manner as in Example 2 except that a fluorine-modified silicone resin having a hardness of JIS (A) 60 degrees was used. The connection loss in this case was 1.4 dB. It is considered that the signal light was refracted and scattered because the optical fibers did not adhere to each other because the light transmitting body was hard.

[0031]

According to the present invention, a practical connection part can be provided, and anyone can easily and reliably make an optical connection with little loss at home. The layman can attach himself to the optical fiber using a conventional connection device. Above all, since no complicated construction is required, quick and inexpensive and easy connection is possible, which is very useful for the spread of optical communication systems.

[Brief description of the drawings]

FIG. 1 is a view showing one example of a connection component of the present invention.

FIG. 2 is a view showing one example of a connection component assembly of the present invention.

FIG. 3 is a diagram showing a mounting example of a connection component of the present invention.

FIG. 4 is a view showing an example of a method for manufacturing a connection component of the present invention.

[Explanation of symbols]

 11, 21, 31, 41 Light transmitting body 12, 22, 32, 42 Adhesive body 23, 43 Receiver 24, 44 Release film 30 Connecting component 35 Optical fiber 36 Ferrule 37 Optical semiconductor 38 Plug 39 Socket 40 Raw material of light transmitting body

Claims (8)

[Claims] 1. A component to be optically connected by interposing a flexible light transmitting body between an optical fiber and optical components (optical fiber, optical semiconductor, etc.), and to be attached to the tip of the optical fiber. An optical fiber connecting part, comprising a light-transmitting adhesive layer on one side. 2. An optical fiber connecting component according to claim 1, wherein the adhesive layer surface is brought into close contact with the optical fiber for use. 3. The structure according to claim 1, wherein the opposite side of the pressure-sensitive adhesive layer has a convex structure in which the thickness decreases continuously or stepwise from the center toward the outer periphery. The connection component for an optical fiber according to 1. 4. The optical fiber according to claim 1, wherein the refractive index of the light transmitting body and the adhesive is within ± 0.05 of the refractive index of the optical fiber. Connection parts. 5. The light transmitting body according to claim 1, wherein the light transmitting body is at least one selected from silicone resins, acryl resins, epoxy resins, thermoplastic elastomer resins and derivatives of these resins having a hardness of 50 degrees or less according to JIS (A type). The optical fiber connection component according to any one of claims 1 to 4, wherein the component is a seed. 6. A method for producing an optical fiber connecting part characterized by being produced in the following steps: 1) applying a precursor liquid of a light transmitting body onto a release film; Solidify the permeable body 3) Apply the adhesive and cover the surface with a release film, or attach the adhesive coated release film 4) Half cut the connection part shape from the adhesive side 7. A method for manufacturing an optical fiber connection part characterized by being manufactured in the following steps: 1) Filling a receiver having a recessed hole with a light transmitting material, 2) Heating, cooling, etc. 3) Apply an adhesive and cover the surface with a release film, or attach an adhesive coated release film 8. The method for manufacturing an optical fiber connecting part according to claim 6, wherein the optical fiber connecting part is manufactured continuously.