JPH05203829A - Loop-back optical connector device - Google Patents

Abstract

PURPOSE:To provide a structure which provides the integration and unification of multiunits of the loop-back optical connector device. CONSTITUTION:This device is equipped with at least a couple of single mode type optical fibers 11 and 15, a 2nd optical connector 5 having grated index type optical fibers 12 for incidence which make a light signal from one of the single mode type optical fibers 11 and 15 incident and graded index type optical fibers 14 for projection which project a light signal on the other optical fiber 11 or 15, and a reflecting means 16 which reflects the light signal from the optical fibers 12 for incidence and makes the light incident on the graded index type optical fibers 14 for projection.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a loopback optical connector device for returning an optical signal in an optical communication line.

[0002]

2. Description of the Related Art In optical communication, a failure of a transmission line causes the entire system to go down, so reliability measures are essential. Therefore, when optical communication is performed using the ring type optical LAN, when the cable is cut at one point of the ring,
The system must be restored by folding back the optical signal on the transmission lines at both ends closest to the cut point. A loopback function is provided as a device for performing the loopback ("The present and future of optical communication technology", edited by the Telecommunications Technology Council, (Issuer) Gyosei Co., Ltd., (Issue date) Showa 6
(See p.88, March 1, 2012).

FIG. 4 shows a conventional loopback optical connector device in which an optical communication system has a loopback function. In this loopback optical connector device, two single mode type optical fibers 10 are connected, and an optical connector 2 whose one end is exposed at an optical coupling surface A and a loop part L by two single mode type optical fibers 10. And an optical connector 3 whose one end is exposed on the optical coupling surface B.

[0004]

However, in the conventional loopback optical connector device, since the optical signal is folded back by using the loop portion L formed of the optical fiber having rigidity, the device becomes large in size, It was difficult to integrate the devices and put them together.

Therefore, it is an object of the present invention to provide a structure capable of realizing integration of a loopback optical connector device and integration of multiple fibers.

[0006]

According to the present invention, there is provided a first optical connector having at least a pair of single mode type optical fibers, and an input gray for receiving an optical signal from one of the pair of single mode type optical fibers. A second optical connector having a dead index optical fiber for emitting an optical signal to the other of the dead index optical fiber and the pair of single mode optical fibers, and an optical connector mounted on the second optical connector for incidence. And a reflection means for reflecting an optical signal from the graded index optical fiber and entering the same into the outgoing graded index optical fiber.

[0007]

According to the present invention, the optical signal emitted from the single mode type optical fiber enters the graded index type optical fiber, is reflected by the reflecting means (reflection mirror, etc.), and then passes through the graded index type optical fiber. Return to single mode optical fiber. Therefore, the optical signal is returned at a short distance.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A loopback optical connector device according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a diagram showing the principle of the loopback according to the present invention, FIG. 2 is a diagram showing the internal structure of the loopback optical connector device according to the present embodiment using this principle, and FIG. 3 is a diagram showing the present embodiment. It is a figure which shows the external appearance of the loopback optical connector apparatus which concerns.

First, the basic principle applied to the present invention will be described with reference to FIG. Single-mode optical fiber (hereinafter referred to as "SM-type optical fiber") has a small signal distortion because it transmits only one mode, and also has a small transmission index due to a small difference in refractive index between the core and the clad. It is small and suitable for long distance and large capacity optical communication system.
On the other hand, a graded index type optical fiber (hereinafter,
It is called "GI type optical fiber". ) Is used in the medium capacity optical communication system because it is easier to connect and couple with the light source than the SM type optical fiber.

In the present invention, an optical communication system includes a pair of S
The M type optical fibers 11 and 15 are used, and a GI type optical fiber (incident GI type optical fiber) 1 is used as a folded portion thereof.
2. GI type optical fiber (GI type optical fiber for emission) 14
And a reflection mirror (reflecting means) 13 (see FIG. 1). The SM type optical fibers 11 and 15 are juxtaposed in parallel with each other, for example, and a pair of GI type optical fibers 1 are provided at the ends thereof.
One end of each of 2 and 14 is connected so as to be optically coupled.
A reflection mirror 1 is provided on the other end of the GI type optical fibers 12 and 14.
3 are arranged. The reflection mirror 13 is composed of two mirror surfaces 13a and 13b arranged at intervals of 90 degrees. For example, the mirror surface 13a faces the GI type optical fiber 12 and the mirror surface 13b faces the GI type optical fiber 14. is set up. Therefore, the light from the GI type optical fiber 12 is irradiated to the mirror surface 13a, reflected by the mirror surface 13b, and then returns to the GI type optical fiber 14 by forming an optical path parallel to the incident light on the mirror surface 13a. The light that has entered the GI type optical fiber 14 enters the SM type optical fiber 15 and is returned to the optical communication system.

As described above, in the present invention, the SM type optical fiber having a small transmission loss is used in most of the optical communication system, and the connection and the coupling with the light source are easy at the folded portion accompanied by the emission and the incidence of light. It is reflected by a reflection mirror via a GI type optical fiber. Therefore, the size of the device is reduced as a whole, and transmission loss is reduced and connection is facilitated.

Next, an embodiment of the present invention to which the above-mentioned basic principle is applied will be described with reference to FIGS. Figure 2
3 shows an example of the internal structure of the loopback optical connector device shown in FIG. The loopback optical connector device according to the present embodiment includes an SM type optical connector (first optical connector) 4, G
The I-type optical connector (second optical connector) 5 and the reflection member (reflection means) 6 are included (see FIG. 3).

The SM type optical connector 4 has an even number (for example, 1
(0) SM type optical fibers 15 are arranged in parallel with each other, and their ends are exposed at the optical coupling surface of the SM type optical connector 4. The GI type optical connector 5 has an SM at one end.
It has an optical coupling surface for optical coupling with the optical connector 4, and a reflecting member 6 is fixed to the other end. The GI type optical connector 5 has the same number of GI type optical fibers 12, 14 as the SM type optical fibers 11, 15 arranged in the SM type optical connector 4.
Are arranged at the same intervals, and their ends are exposed at the optical coupling surface of the GI type optical connector 5. The reflecting member 6 is made of a material that transmits the light used in the optical communication system,
A flat surface is formed at one end and a V groove is formed at the other end. The V groove is composed of two planes inclined at about 90 degrees, and the mirror portion 16 is formed on the surface thereof.

Therefore, if the SM type optical connector 4 and the GI type optical connector 5 are opposed to each other on the optical coupling surface, the SM type optical fiber 11 and the GI type optical fiber 12, and further the SM type optical fiber 15 and the GI type optical fiber 14 are provided. Are optically coupled to each other, and the optical signal emitted from the GI type optical fiber 12 is returned by the mirror section 16 in the opposite direction along the optical path parallel to the incident optical path and is returned.

As described above, by using the loopback optical connector device according to the present embodiment, the required space can be reduced and the integration and the multi-fiber integration can be achieved (see FIG. 2). In the present invention, the shape, structure, size, etc. of the optical connector, and the number, shape, and arrangement of the single mode optical fiber and the graded index optical fiber are not limited to those in the above embodiment.

Further, the reflecting means may be integral with or separate from the second optical connector. What is important is that the optical signal from the SM type optical fiber enters the reflecting means via the GI type optical fiber and enters the SM type optical fiber via the GI type optical fiber.

[0018]

According to the present invention, since the optical signal from the SM type optical fiber is returned to the SM type optical fiber through the GI type optical fiber and the reflecting means, the transmission loss can be minimized. , It is possible to fold back the optical signal in a short distance. Therefore, the loopback optical connector device can be downsized, which facilitates integration of the device and integration of multiple fibers.

[Brief description of drawings]

FIG. 1 is a diagram showing the principle of loopback according to the present invention.

FIG. 2 is a diagram showing an internal structure of a loopback optical connector device according to the present embodiment using the above principle.

FIG. 3 is a diagram showing an appearance of a loopback optical connector device according to an embodiment of the present invention.

FIG. 4 is a conceptual diagram showing a conventional loopback optical connector device in which an optical communication system has a loopback function.

[Explanation of symbols]

2, 3 ... Optical connector, 4 ... SM type optical connector, 5 ... GI
Type optical connector, 6 ... Reflective member, 10, 11, 15 ... SM
Type optical fiber, 12, 14 ... GI type optical fiber, 13 ...
Reflection mirror, 16 ... Mirror section, A, B ... Optical coupling surface, L ...
Loop part.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadashi Haibara 1-6, 1-chome, Saiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation

Claims (1)

[Claims] 1. A loopback optical connector device for returning an optical signal in an optical communication line, comprising: a first optical connector having at least a pair of single mode optical fibers; and one of the pair of single mode optical fibers. A second optical connector having an incident graded-index optical fiber for injecting an optical signal and an emission graded-index optical fiber for emitting an optical signal to the other of the pair of single-mode optical fibers; Means for reflecting an optical signal from the graded index type optical fiber for use and making it enter the output graded index type optical fiber.