JPH05273479A - Repeater for optical communication - Google Patents

Abstract

PURPOSE:To obtain a repeater for optical communication capable of automatically branching and returning an optical signal corresponding to working status in an optical communication system consisting of plural optical fiber communication equipments. CONSTITUTION:This repeater fetches the optical signal sent from the outside in a main input/output terminal 10, and equipped with a branch optical system 12 which transmits the optical signal by branching into plural sub input/output terminals 11a, 11b, and the sub input/output terminals 11a, 11b are connected optically to the main input/output terminal 10 when external terminals 21, 22 are mounted on the sub input/output terminals 11a, 11b. When the external terminals are dismounted, the optical signal sent from the main input/output terminal 10 by the function of a tension spring 14 and a stopper 15 is returned to the main input/output terminal 10 by an optical prism 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a repeater used in, for example, optical communication, and more particularly to a branching device for automatically branching an optical signal depending on a connection state of an optical fiber connector provided in an optical signal transmission path. The present invention relates to an optical communication repeater having a function and a terminator function that automatically returns an optical signal.

[0002]

2. Description of the Related Art An optical fiber communication device includes an optical transmission section for modulating an electric signal into an optical signal, an optical reception section for receiving the optical signal sent from the optical transmission section and demodulating it again into an electric signal. It is composed of an optical transmission line that connects the optical transmission unit and the optical reception unit, and such optical fiber communication can transmit a television image having an extremely large transmission band at high speed, low loss, and space saving. Attempts are being made to apply it to video communication.

A light emitting diode (LED) or a laser diode (LD), for example, is used in the optical transmission section in order to generate a digital optical signal or the like according to a predetermined electric signal. On the other hand, an avalanche photodiode (APD) or a PIN photodiode, for example, is used in the optical receiver, and after demodulating the digital optical signal transmitted from the optical transmitter into an electric signal, the electric signal is connected to the outside. It is designed to output to various devices. Also, it has been attempted to connect a plurality of optical fiber communication devices via an optical transmission line to perform information exchange / information processing by optical signals.
In such a case, an optical fiber connector is used to connect the optical fiber communication devices with each other through an optical transmission line formed of an optical fiber cable.

For example, as shown in FIG. 3B, a plurality of optical fiber communication devices A _1, A _2, ... A _n are connected by an optical transmission line, and the communication device A _{1 at the start} end to the communication device A at the end end. _{In the} case where information processing is performed by each communication device while sequentially transmitting optical signals up to _n , each optical fiber communication device A _1, A _2, ... A _n
Is provided with input / output terminals 1 and 2 used for exchanging optical signals with respective optical fiber communication devices connected to the upstream side and the downstream side. An optical fiber cable 3 serving as an optical transmission line is installed between and. This optical fiber cable 3
An optical fiber connector 4 is formed between the end of the optical fiber cable and the input / output terminals 1 and 2, and each optical fiber cable 3 as an optical transmission line is connected to the optical fiber communication device A _1, A ₂ by this optical fiber connector 4. _, ... Can be attached to and detached from A _n .

[0005]

By the way, FIG. 3 (A)
As shown in, there are cases where it is desired to branch the optical signal sent from the optical fiber communication device A ₂ to the two optical fiber communication devices A _{n and} A _{n + 1} for transmission. In such a case, an optical branching device 5 is provided in the middle of the optical fiber cable 3 connecting the optical fiber communication device A ₂ and the optical fiber communication device A _n, and _two optical signals from the optical fiber communication device A ₂ are provided. The optical fiber communication devices A _{n and} A _{n + 1} are split to transmit the same information to the respective optical fiber communication devices, or in addition to this,
The information processed by these optical fiber communication devices A _{n and} A _{n + 1} is returned to the optical fiber communication device A ₂ again.

Further, as shown in FIG. 3C, the optical fiber communication device A _{1 at the start} end to the optical fiber communication device A at the end end.
_{In the} optical communication system for exchanging information, for example, when the information processing result reaching the optical fiber communication device A ₂ is returned to the starting optical fiber communication device A ₁ after transmitting the optical signal up to ₂ , Since there is a problem that the input / output terminal 2 of the deployed optical fiber communication device A ₂ is in an open state, it is necessary to attach a so-called terminator 6 for returning an optical signal here.

As described above, when a plurality of optical fiber communication devices are connected by an optical fiber cable to exchange information and process information, the communication system shown in FIGS. However, the optical splitters and terminators used in conventional optical fiber communication devices cannot all be shared, so each time, the equipment according to the usage situation is replaced by an optical fiber cable. Had to be installed or replaced.

The present invention has been made in view of the above problems of the prior art. In an optical communication system configured by connecting a plurality of optical fiber communication devices, the present invention automatically It is an object of the present invention to provide an optical communication repeater capable of branching an optical signal and automatically returning the optical signal.

[0009]

In order to achieve the above object, an optical communication repeater of the present invention takes in an optical signal sent from the outside from a main input / output terminal and outputs the optical signal to a plurality of sub-inputs. In an optical communication repeater having branching means for branching and transmitting to an output terminal, when an external terminal is attached to the sub input / output terminal, the sub input / output terminal and the main input / output terminal are optically connected. At the same time, it is characterized by including an optical path changing means for returning an optical signal sent from the main input / output terminal to the main input / output terminal when the external terminal is removed.

[0010]

When an external terminal is attached to the sub input / output terminal provided in the repeater for optical communication of the present invention and an optical signal is taken in from the main input / output terminal, this optical signal is branched by the branching means and each sub terminal is divided. It reaches the input / output terminal and is output from here to the external terminal. Further, the optical signals input from the respective sub input / output terminals are combined by the branching means to reach the main input / output terminal,
It is output from here. As described above, when the external terminals are attached to the respective sub-input / output terminals, the optical communication repeater of the present invention functions as an optical branching device.

On the other hand, when the external terminal is attached to only one sub input / output terminal and the external terminal is removed from the other sub input / output terminals, the optical signal taken in from the main input / output terminal is branched by the branching means. The optical signal sent from the branching means by the optical path changing means is automatically returned to the main input / output terminals at the auxiliary input / output terminals which are connected to the respective auxiliary input / output terminals, but the external terminals are not attached. Therefore, the optical signal sent from the main input / output terminal is transmitted only to the sub input / output terminal to which the external terminal is attached. Thus, when the external terminal is attached to only one sub input / output terminal, the optical communication repeater of the present invention functions as a normal optical repeater.

Further, when the external terminals are removed from all the sub input / output terminals, the optical signal sent from the branching means by the optical path changing means is automatically returned to the main input / output terminals at each sub input / output terminal. To be done. Therefore, all optical signals sent from the main input / output terminal are returned to the main input / output terminal. Thus, when the external terminals are removed from all the sub-input / output terminals, the optical communication repeater of the present invention is
It will control the function of the terminator.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 is a block diagram showing an optical communication repeater according to an embodiment of the present invention, FIG. 2A is a block diagram showing a branching unit according to an embodiment of the present invention, and FIG. It is a block diagram which shows the branch means which concerns on an Example. An embodiment of an optical communication system using the optical communication repeater of the present invention is shown in FIG.
This will be described with reference to (C).

The optical communication repeater of the embodiment shown in FIG. 1 is a specific example in which an optical signal sent from an optical transmitter is split into two transmission lines and transmitted to an optical receiver. The main body of the optical communication repeater is provided with a main input / output terminal 10 for taking in an optical signal sent from the outside or returning the optical signal to the outside, and is composed of an optical fiber. It is connected to the optical transmission line 17. The base end of this optical transmission line 17 is connected to a branching optical system 12 which is a branching unit described later, while the tip end forms a connector 20 to which an external terminal is connected.

Further, the main body of the optical communication repeater is provided with two sub-input / output terminals 11a and 11b, and an optical signal taken in from the main input / output terminal 10 via the branch optical system 12 is externally supplied. Transmit to. Each sub-input / output terminal 11
a and 11b are connected to optical transmission lines 18 and 19 formed of flexible optical fibers.
The proximal end of 19 is connected to the branch optical system 12, while the distal end forms connectors 21 and 22 to which external terminals are connected.

The connection structure of such connectors 20, 21, 22 is based on the premise that the core of the optical fiber is concentric with the clad, and the central axis is set to a size such that the optical fiber can be inserted into the hole of the ferrule with almost no gap. You just have to open it above. At this time, the connectors 20 and 2 of the optical fiber cable
1, 22 and the input / output terminals 10, 11a, 11b are formed so that the connector 20 and the main input / output terminal 10 and the connectors 21, 22 and the sub input / output terminals 11a, 11b are formed with engaging portions. Keep it.

As described above, when a plurality of optical fiber communication devices are connected by an optical fiber cable for exchanging information or information processing, the communication system shown in FIGS. 3 (A) to 3 (C) is used. You may want to change it depending on the situation, but in the optical branching device and terminator used in the conventional optical fiber communication device, all cannot be shared,
Therefore, it is necessary to attach or replace the device according to the usage condition to the optical fiber cable each time. In the present embodiment, the problem in such a repeater for optical communication, that is, the optically opened state of the sub input / output terminal is automatically processed by the connection state of the external terminal.

That is, as shown in FIG. 1, optical transmission lines 18 and 19 formed of flexible optical fibers.
When the optical fiber connectors 21 and 22 which are external terminals are attached, the main input / output terminal 10 and the sub input / output terminal 1
The optical fibers 1a and 11b are moved so as to transmit an optical signal sent from the branch optical system 12 or sent to the branch optical system 12 so as to be optically connected (shown by a solid line in FIG. 1) and an optical fiber. When the connectors 21 and 22 are removed, the tip ends of the optical transmission paths 18 and 19 move so as to face the optical prism 13 (shown by a chain double-dashed line in FIG. 1).

Although the specific means for switching the optical transmission lines 18 and 19 is not particularly limited, for example, in this embodiment, the tension spring 14 is attached to the optical transmission lines 18 and 19 to transmit the optical transmission. The tip of the path is urged in a direction to move to a position facing the optical prism 13.
Further, at this position, the stopper 1 is arranged so that the tips of the optical transmission paths 18 and 19 stop at appropriate positions with respect to the optical prism 13.
5 are provided. On the other hand, the optical fiber connector 2
When the Nos. 1 and 22 are attached, the sub input / output terminals 11a and 11
By operating the cam means (not shown) provided in b,
The optical transmission paths 18 and 19 are moved to the position where they are connected to the optical fiber connectors 21 and 22 against the elastic force of the tension spring 14. Even at this position, the stopper 16 is moved so that the optical transmission line moves to an appropriate position and stops.
Is formed.

On the other hand, the optical prism 13 changes the optical path of the optical signal so that the branch optical system 12 moves the auxiliary input / output terminal 11a,
It has a function of returning the optical signal sent to 11b to the branching optical system 12 again, and when the tips of the optical transmission lines 18 and 19 face each other, the optical signals transmitted from the optical transmission lines 18 and 19 become optical signals. The optical transmission paths 18 and 19 are reflected by the prism 13 and are reflected again.
It is structured to be returned to. Therefore, the present invention is not limited to the optical prism, but the branch optical system 12
Any means may be used as long as it has a function of returning the optical signals sent from the sub input / output terminals 11a and 11b to the branch optical system 12 again. In this way, the optical prism 13 for returning the optical signal,
Extension spring 1 for moving the optical transmission lines 11a, 11b
4, the stoppers 15 and 16, the cam means (not shown) and the like constitute the optical path changing means of the present invention.

FIG. 2A shows a concrete example of the branch optical system 12 according to the present embodiment, in which "23" is a half mirror, and an optical signal from the main input / output terminal 10 is converted into two light beams. Two optical transmission lines 1 are provided while branching to the transmission lines 11a and 11b.
It controls the function of synthesizing the optical signals transmitted from 1a and 11b and guiding them to the main input / output terminal 10. Further, "24" is a condenser lens for condensing an optical signal, and it is preferable to provide it as necessary. When the optical signals that have been branched once are combined again, it is necessary to provide means for adjusting the phase of the light.

Next, a concrete example in which the above-mentioned optical communication repeater of this embodiment is applied to an optical communication system will be described with reference to FIG.
Description will be made with reference to (A) to (C). Although not shown, the optical fiber communication device shown in FIG.
An optical receiver, a drive circuit, an information processing circuit, etc. are provided, and the optical transmitter is composed of a semiconductor device such as a light emitting diode (LED) or a laser diode (LD) for modulating an electric signal into an optical signal. On the other hand, in order to demodulate the optical signal into an electrical signal, the optical receiving unit may, for example, use an avalanche photodiode (APD) or PIN.
It is composed of semiconductor devices such as photodiodes.

The optical transmission section and the optical reception section composed of such a semiconductor device are connected so as to be driven by a drive circuit, and the reception section is provided via an optical fiber cable, an optical fiber connector, and an optical transmission path. The optical signal received by is demodulated into an electrical signal and then output to the information processing circuit, or the electrical signal output from the information processing circuit is modulated into an optical signal and transmitted from the transmitter to an optical transmission line, an optical fiber connector, It outputs to an external device via an optical fiber cable.

First, when the optical communication system is constructed as shown in FIG. 3A, the optical signal sent from the optical fiber communication device A ₂ is the main input / output terminal of the optical communication repeater of this embodiment. 10 and is branched by the branch optical system 12 to reach the respective sub input / output terminals 11a and 11b. And
From here, it is output to the external terminals 21 and 22, and is input to each of the optical fiber communication devices A _{n and} A _{n + 1} . Further, the optical signals (returning optical signals) output from the respective optical fiber communication devices A _{n and} A _{n + 1} are input from the sub input / output terminals 11a and 11b of the optical communication repeater of this embodiment, The light is combined by the branch optical system 12 to reach the main input / output terminal 10, from which it is output to the optical fiber communication device A ₂ . in this way,
An external terminal 2 is provided on each of the sub-input / output terminals 11a and 11b.
The optical communication repeater according to the present embodiment is equipped with
It will be responsible for the function of the optical branching device.

On the other hand, when the optical communication system is constructed as shown in FIG. 3B, that is, the external terminal is attached to only one sub input / output terminal and the external terminal is removed from the other sub input / output terminals. In this case, the optical signal sent from the optical fiber communication device A ₂ is input to the main input / output terminal 10 of the optical communication repeater of this embodiment, branched by the branch optical system 12, and each sub input / output terminal 11a. , 11b, but the optical transmission path is moving at the sub input / output terminal to which the external terminal is not attached, and the optical signal sent from the branch optical system 12 by the optical prism 13 is automatically input to the main input / output terminal. Returned to 10.
Accordingly, the optical signal transmitted from the main input and output terminal 10 will be transmitted sub input and output terminals of the external terminal is attached, that is, optical fiber communication apparatus A _n only. When the external terminal is attached to only one sub-input / output terminal in this way, the optical communication repeater of this embodiment functions as a normal optical repeater.

Further, when the optical communication system is configured as shown in FIG. 3B, that is, when the external terminals are removed from all the sub input / output terminals 11a and 11b, the sub input / output terminals 11a and 11b are removed. In 11b, the optical transmission paths 18 and 19 are moving, and the optical signal sent from the branch optical system 12 by the optical prism 13 is automatically returned to the main input / output terminal 10. Therefore, the optical signal sent from the optical fiber communication device A ₂ is input to the main input / output terminal 10 of the optical communication repeater of this embodiment, and is branched by the branch optical system 12 so that each sub input / output terminal 11a, 11b, all the optical signals are returned to the main input / output terminal 10. When the external terminals are removed from all the sub-input / output terminals in this way, the optical-communication repeater according to the present embodiment functions as a terminator.

The present invention is not limited to the above-mentioned embodiments, but can be modified. For example, in this embodiment, the optical transmission line is configured to be moved depending on the connection state of the optical fiber connector which is the external terminal, but the optical transmission line may be fixed and the optical prism side may be moved. .. Further, the optical communication repeater of the present invention is not limited to the above-described two sub input / output terminals 11a and 11b, but may be provided with three or more sub input / output terminals. The branching optical system in this case can be realized by the configuration shown in FIG. 2B, and the repeater body may be configured by adding a sub input / output terminal similar to the sub input / output terminal described above. ..

[0028]

As described above, according to the present invention, there is provided branching means for taking in an optical signal sent from the outside from the main input / output terminal and branching the optical signal to a plurality of sub input / output terminals for transmission. In the equipped optical communication repeater, when the external terminal is attached to the sub input / output terminal, the sub input / output terminal and the main input / output terminal are optically connected, and when the external terminal is removed, the main input / output terminal Since it has an optical path changing means for returning the optical signal sent from the main input / output terminal to the main input / output terminal, in the optical communication system configured by connecting a plurality of optical fiber communication devices, the optical signal is automatically changed according to the usage condition. Can be branched or automatically returned.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an optical communication repeater according to an embodiment of the present invention.

2A is a configuration diagram showing a branching unit according to an embodiment of the present invention, and FIG. 2B is a configuration diagram showing a branching unit according to another embodiment.

3A to 3C are configuration diagrams showing a conventional optical communication system.

[Explanation of symbols]

 10 ... Main input / output terminals 11a, 11b ... Sub input / output terminals 12 ... Branching optical system (branching means) 13 ... Optical prism (optical path changing means) 14 ... Extension spring (optical path changing means) 15, 16 ... Stopper (optical path changing means) )

Claims (1)

[Claims] 1. An optical communication repeater comprising branching means for taking in an optical signal sent from the outside from a main input / output terminal and branching the optical signal to a plurality of sub input / output terminals for transmission. When an external terminal is attached to the input / output terminal, the sub input / output terminal is optically connected to the main input / output terminal, and when the external terminal is removed, the optical signal sent from the main input / output terminal is An optical communication repeater having an optical path changing means for returning to a main input / output terminal.