JPH06177837A - Output shutdown controller for high output light transmitting part - Google Patents
Output shutdown controller for high output light transmitting partInfo
- Publication number
- JPH06177837A JPH06177837A JP43A JP33067392A JPH06177837A JP H06177837 A JPH06177837 A JP H06177837A JP 43 A JP43 A JP 43A JP 33067392 A JP33067392 A JP 33067392A JP H06177837 A JPH06177837 A JP H06177837A
- Authority
- JP
- Japan
- Prior art keywords
- signal light
- connector
- output
- threshold value
- reflection amount
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/0014—Monitoring arrangements not otherwise provided for
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/10007—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating in optical amplifiers
- H01S3/1001—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating in optical amplifiers by controlling the optical pumping
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/13—Stabilisation of laser output parameters, e.g. frequency or amplitude
- H01S3/1301—Stabilisation of laser output parameters, e.g. frequency or amplitude in optical amplifiers
- H01S3/13013—Stabilisation of laser output parameters, e.g. frequency or amplitude in optical amplifiers by controlling the optical pumping
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Optics & Photonics (AREA)
- Optical Communication System (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、光アンプを用いて増幅
した信号光を送出しているときに、コネクタに伝送路ケ
ーブルが接続されているか否かに応じて信号光出力の調
節を行う高出力光送信部の出力シャットダウン制御装置
に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention adjusts a signal light output depending on whether or not a transmission line cable is connected to a connector while transmitting a signal light amplified by an optical amplifier. The present invention relates to an output shutdown control device for a high output light transmitter.
【0002】[0002]
【従来の技術】光アンプを利用する光送信部では、高レ
ベルの信号光が出力されるようになっている。この高レ
ベルの信号光は、出力端からコネクタを介して伝送路ケ
ーブルに送出され、通信に用いられているときには問題
はない。しかし、何らかの事情でコネクタが離脱したと
きは、光送信部の動作を停止させない限りコネクタ端面
から高レベルの信号光が出力され、場合によってはそれ
が人間の目に入ることもあるために適当な保護手段が必
要になっている。2. Description of the Related Art An optical transmitter using an optical amplifier outputs high-level signal light. This high-level signal light is sent from the output end to the transmission line cable via the connector, and there is no problem when it is used for communication. However, if the connector is disconnected for some reason, a high level of signal light is output from the end face of the connector unless the operation of the optical transmitter is stopped, and in some cases it may be seen by human eyes. Protective measures are needed.
【0003】[0003]
【発明が解決しようとする課題】ところで、コネクタの
離脱・接続の都度、手動で高出力光送信部の動作を制御
することは容易ではない。そこで、コネクタが離脱した
ときには自動的に信号光出力をシャットダウンさせ、コ
ネクタが再度接続されたときには信号光出力をアップ
し、自動的に元の状態に回復させる装置が望まれてい
る。By the way, it is not easy to manually control the operation of the high-power optical transmitter each time the connector is disconnected and connected. Therefore, there is a demand for a device that automatically shuts down the signal light output when the connector is detached, increases the signal light output when the connector is reconnected, and automatically restores the original state.
【0004】本発明は、このような要望に応えるため
に、光アンプを用いて増幅した信号光を送出する高出力
光送信部において、コネクタの離脱・接続に応じて信号
光出力を制御することができる高出力光送信部の出力シ
ャットダウン制御装置を提供することを目的とする。In order to meet such a demand, the present invention controls a signal light output in accordance with disconnection / connection of a connector in a high output light transmitter which sends out signal light amplified by an optical amplifier. It is an object of the present invention to provide an output shutdown control device for a high-power optical transmitter that can perform the above.
【0005】[0005]
【課題を解決するための手段】請求項1に記載の発明
は、高出力光送信部から出力される信号光がコネクタ端
面で反射した反射光をモニタし、その反射量を検出する
反射量検出手段と、反射量が所定の閾値を下回るときに
は信号光出力を所定レベルに設定し、反射量が所定の閾
値を上回るときには信号光出力を低下させる光信号出力
制御手段とを備えて構成する。According to a first aspect of the present invention, a signal amount output from a high output optical transmitter is monitored by a reflected light reflected from an end face of a connector, and the reflected amount is detected. And an optical signal output control unit that sets the signal light output to a predetermined level when the reflection amount is below a predetermined threshold value and reduces the signal light output when the reflection amount is above the predetermined threshold value.
【0006】請求項2に記載の発明は、高出力光送信部
から出力される信号光とは異なる波長を有するモニタ光
を信号光に波長多重して送信するモニタ光送信手段と、
モニタ光がコネクタ端面で反射した反射光をモニタし、
その反射量を検出する反射量検出手段と、反射量が所定
の閾値を下回るときには信号光出力を所定レベルに設定
し、反射量が所定の閾値を上回るときには光信号出力を
低下させる光信号出力制御手段とを備えて構成する。According to a second aspect of the present invention, there is provided monitor light transmitting means for wavelength-multiplexing and transmitting the monitor light having a wavelength different from that of the signal light output from the high output light transmitter.
Monitor the reflected light reflected from the connector end face,
Reflection amount detecting means for detecting the reflection amount, and optical signal output control for setting the signal light output to a predetermined level when the reflection amount is below a predetermined threshold value and lowering the optical signal output when the reflection amount exceeds the predetermined threshold value. And means.
【0007】[0007]
【作用】コネクタが接続され、高出力光送信部の出力端
と伝送路ケーブルとが接続されているときには、高出力
光送信部から出力される信号光のコネクタ端面における
反射量が小さい。一方、コネクタが離脱しているときに
は、高出力光送信部から出力される信号光のコネクタ端
面における反射量が大きい。これは、信号光とは異なる
波長を有するモニタ光のコネクタ端面における反射量に
ついても同様である。When the connector is connected and the output end of the high output light transmitter is connected to the transmission line cable, the amount of signal light output from the high output light transmitter is small on the connector end face. On the other hand, when the connector is detached, the amount of signal light output from the high-power optical transmitter is largely reflected by the end face of the connector. The same applies to the amount of reflection of the monitor light having a wavelength different from that of the signal light on the connector end face.
【0008】請求項1に記載の発明では、コネクタが接
続されているときには信号光の反射量が減少して所定の
閾値を下回ることになるので、それに応じて信号光出力
を所定レベルに設定する。一方、コネクタが離脱してい
るときには、信号光の反射量が増加して所定の閾値を上
回ることになるので、それに応じて信号光出力を低下さ
せる。According to the first aspect of the invention, when the connector is connected, the amount of reflection of the signal light decreases and falls below a predetermined threshold value. Therefore, the signal light output is set to a predetermined level accordingly. . On the other hand, when the connector is detached, the reflection amount of the signal light increases and exceeds the predetermined threshold value, so that the signal light output is reduced accordingly.
【0009】なお、信号光出力を低下させてもコネクタ
端面における反射量が増えるので、コネクタからの反射
光のモニタは可能である。この反射光をモニタし、コネ
クタが再度接続されたときに反射量が所定の閾値を下回
ることを検出することにより、信号光出力を所定レベル
まで自動的に回復させることができる。Even if the signal light output is reduced, the amount of reflection at the end face of the connector increases, so that the light reflected from the connector can be monitored. By monitoring this reflected light and detecting that the amount of reflection falls below a predetermined threshold when the connector is reconnected, the signal light output can be automatically restored to a predetermined level.
【0010】請求項2に記載の発明では、信号光とは異
なる波長を有するモニタ光の反射光を用いる点に特徴が
ある。すなわち、本発明ではコネクタが離脱すると、同
様に反射量が所定の閾値を上回ることになり、信号光出
力を低下させることができる。なお、コネクタの再接続
は、モニタ光の反射光によって監視することができるの
で、コネクタ離脱時の信号光出力を完全に遮断してもよ
い。The invention according to claim 2 is characterized in that the reflected light of the monitor light having a wavelength different from that of the signal light is used. That is, in the present invention, when the connector is detached, the reflection amount similarly exceeds a predetermined threshold value, and the signal light output can be reduced. Since the reconnection of the connector can be monitored by the reflected light of the monitor light, the signal light output at the time of disconnection of the connector may be completely cut off.
【0011】[0011]
【実施例】コネクタ端面における信号光あるいはモニタ
光の反射量は、各反射光の絶対レベル(dBm)から絶対
反射量を検出する方法と、信号光あるいはモニタ光に対
する反射光の相対レベル(dB)から相対反射量を検出す
る方法がある。以下、各方法に対応する実施例を併記し
て説明する。[Embodiment] The reflection amount of the signal light or the monitor light on the connector end face is detected by the absolute level (dBm) of each reflection light, and the relative level (dB) of the reflection light to the signal light or the monitor light. There is a method of detecting the relative reflection amount from. Hereinafter, examples corresponding to each method will be described together.
【0012】図1は、請求項1に記載の発明の実施例構
成を示すブロック図である。(a) は、反射光の絶対レベ
ル(dBm)から絶対反射量を検出する方法を用いた実施
例であり、(b) は反射光の信号光に対する相対レベル
(dB)から相対反射量を検出する方法を用いた実施例で
ある。FIG. 1 is a block diagram showing the configuration of an embodiment of the invention described in claim 1. In FIG. (a) is an embodiment using the method of detecting the absolute reflection amount from the absolute level (dBm) of the reflected light, and (b) is the relative reflection amount from the relative level (dB) of the reflected light to the signal light. It is an example using the method.
【0013】図1(a) において、高出力光送信部の主要
構成は、電気信号を信号光に変換する電気/光変換部1
1と、信号光を所定レベルまで増幅する光アンプ12
と、光アンプ12から信号光を出力する光ファイバケー
ブル13と、出力端で光ファイバケーブル13と伝送路
ケーブル31とを接続するコネクタ14と、光ファイバ
ケーブル13に挿入されてコネクタ14からの反射光を
分岐する光カプラ15と、反射光の光強度(絶対反射
量)を検出する反射光強度検出回路16と、反射光強度
と所定の閾値(信号光出力シャットダウン閾値および信
号光出力回復閾値)とを比較し、その比較結果に応じた
制御信号を出力する閾値比較回路17と、制御信号によ
り光アンプ12の信号光出力を制御する信号光出力制御
回路18とを備える。In FIG. 1 (a), the main structure of the high-power optical transmitter is an electric / optical converter 1 for converting an electric signal into a signal light.
1 and an optical amplifier 12 that amplifies the signal light to a predetermined level
An optical fiber cable 13 for outputting signal light from the optical amplifier 12, a connector 14 for connecting the optical fiber cable 13 and the transmission path cable 31 at an output end, and a reflection from the connector 14 inserted into the optical fiber cable 13. Optical coupler 15 for branching light, reflected light intensity detection circuit 16 for detecting the light intensity (absolute reflection amount) of reflected light, reflected light intensity and a predetermined threshold (signal light output shutdown threshold and signal light output recovery threshold) And a threshold value comparison circuit 17 for outputting a control signal according to the comparison result, and a signal light output control circuit 18 for controlling the signal light output of the optical amplifier 12 by the control signal.
【0014】図1(b) において、高出力光送信部の主要
構成は、同様の電気/光変換部11,光アンプ12,光
ファイバケーブル13,コネクタ14,光カプラ15,
反射光強度検出回路16および信号光出力制御回路18
と、さらに光ファイバケーブル13に挿入されて光アン
プ12からの信号光を分岐する光カプラ19と、信号光
の光強度を検出する信号光強度検出回路20と、信号光
強度と反射光強度とを比較して相対反射量を検出する相
対反射量検出回路21と、相対反射量と所定の閾値(信
号光出力制御閾値)とを比較し、その比較結果に応じた
制御信号を信号光出力制御回路18に出力する閾値比較
回路22とを備える。In FIG. 1B, the main components of the high-power optical transmitter are the same electric / optical converter 11, optical amplifier 12, optical fiber cable 13, connector 14, optical coupler 15,
Reflected light intensity detection circuit 16 and signal light output control circuit 18
An optical coupler 19 which is further inserted into the optical fiber cable 13 to branch the signal light from the optical amplifier 12, a signal light intensity detection circuit 20 which detects the light intensity of the signal light, a signal light intensity and a reflected light intensity. And a relative reflection amount detection circuit 21 for detecting the relative reflection amount by comparing the relative reflection amount with a predetermined threshold value (signal light output control threshold value), and a signal light output control is performed according to the comparison result. And a threshold value comparison circuit 22 for outputting to the circuit 18.
【0015】なお、請求項1における反射量検出手段
は、光カプラ15および反射光強度検出回路16、ある
いは光カプラ15,反射光強度検出回路16,光カプラ
19,信号光強度検出回路20および相対反射量検出回
路21に対応する。また、光信号出力制御手段は、閾値
比較回路17および信号光出力制御回路18、あるいは
閾値比較回路22および信号光出力制御回路18に対応
する。The reflection amount detecting means in claim 1 is the optical coupler 15 and the reflected light intensity detecting circuit 16, or the optical coupler 15, the reflected light intensity detecting circuit 16, the optical coupler 19, the signal light intensity detecting circuit 20 and the relative. It corresponds to the reflection amount detection circuit 21. The optical signal output control means corresponds to the threshold comparison circuit 17 and the signal light output control circuit 18, or the threshold comparison circuit 22 and the signal light output control circuit 18.
【0016】以下、図2および図3を参照し、具体的数
値例を用いて各実施例の動作について説明する。なお、
以下の説明では、コネクタ14が接続されているときの
コネクタ端面の反射量を−40dBとし、コネクタ14が離
脱しているときのコネクタ端面の反射量を−15dBとす
る。The operation of each embodiment will be described below with reference to FIGS. 2 and 3 by using specific numerical examples. In addition,
In the following description, the amount of reflection on the connector end face when the connector 14 is connected is -40 dB, and the amount of reflection on the connector end face when the connector 14 is disconnected is -15 dB.
【0017】 コネクタ14が接続されている通常時
は、光アンプ12からの信号光出力はコネクタ14を介
して伝送路ケーブル31に送出される。このときの信号
光強度を+15dBmとする。コネクタ14が完全に接続さ
れた状態では信号光の反射は小さく、反射光強度検出回
路16に検出される反射光強度(絶対反射量)は−25dB
mとなる。すなわち、相対反射量検出回路21に検出さ
れる相対反射量は−40dBとなる。When the connector 14 is normally connected, the signal light output from the optical amplifier 12 is sent to the transmission line cable 31 via the connector 14. The signal light intensity at this time is +15 dBm. When the connector 14 is completely connected, the reflection of the signal light is small, and the reflected light intensity (absolute reflection amount) detected by the reflected light intensity detection circuit 16 is -25 dB.
m. That is, the relative reflection amount detected by the relative reflection amount detection circuit 21 is −40 dB.
【0018】 通常時の状態でコネクタ14を離脱
すると、コネクタ14の端面における絶対反射量が0dB
mまで増加する。また、相対反射量は−15dBとなる。こ
こで、絶対反射量と所定の閾値との比較を行う閾値比較
回路17では、図3に示すように絶対反射量が信号光出
力シャットダウン閾値−12.5dBmを越えたことが検出さ
れ、信号光出力の低下を指示する制御信号を出力する。
また、相対反射量と所定の閾値との比較を行う閾値比較
回路22では、図3に示すように相対反射量が信号光出
力制御閾値−27.5dBを越えたことが検出され、信号光出
力の低下を指示する制御信号を出力する。When the connector 14 is detached in the normal state, the absolute reflection amount at the end face of the connector 14 is 0 dB.
increase to m. The relative reflection amount is -15 dB. Here, in the threshold value comparison circuit 17 which compares the absolute reflection amount with a predetermined threshold value, it is detected that the absolute reflection amount exceeds the signal light output shutdown threshold −12.5 dBm as shown in FIG. Output a control signal for instructing the decrease of.
Further, in the threshold value comparison circuit 22 which compares the relative reflection amount with a predetermined threshold value, it is detected that the relative reflection amount exceeds the signal light output control threshold −27.5 dB as shown in FIG. A control signal for instructing the decrease is output.
【0019】 信号光出力制御回路18は、閾値比較
回路17,22から出力される制御信号に応じて、光ア
ンプ12の信号光出力を低下させるように制御する。た
だし、この場合には、光アンプ12の信号光出力は完全
にシャットダウンされるのではなく、人間の目に安全な
レベル(0dBm)まで低下させ、その低下させた信号光
の反射光を反射光強度検出回路16でモニタする。な
お、このときコネクタ14の端面における反射量が増え
ているので、反射光強度検出回路16に検出される反射
光強度(絶対反射量)は−15dBmとなる。相対反射量は
−15dBでコネクタ離脱時と変わらない。The signal light output control circuit 18 controls so as to reduce the signal light output of the optical amplifier 12 according to the control signals output from the threshold value comparison circuits 17 and 22. However, in this case, the signal light output of the optical amplifier 12 is not completely shut down, but is lowered to a level safe for human eyes (0 dBm), and the lowered reflected light of the signal light is reflected light. The intensity detection circuit 16 monitors. At this time, since the amount of reflection on the end face of the connector 14 is increasing, the reflected light intensity (absolute reflection amount) detected by the reflected light intensity detection circuit 16 is -15 dBm. The relative reflection is -15 dB, which is the same as when the connector is disconnected.
【0020】 信号光出力シャットダウン時の状態
でコネクタ14を再度接続すると、コネクタ14の端面
における絶対反射量が−40dBmまで減少する。また、相
対反射量は通常時と同様に−40dBとなる。ここで、絶
対反射量と所定の閾値との比較を行う閾値比較回路17
では、図3に示すように、絶対反射量が信号光出力回復
閾値−27.5dBmを下回ったことが検出され、信号光出力
を当初の状態に戻すことを指示する制御信号を出力す
る。また、相対反射量と所定の閾値との比較を行う閾値
比較回路22では、図3に示すように、相対反射量が信
号光出力制御閾値−27.5dBを下回ったことが検出され、
信号光出力を当初の状態に戻すことを指示する制御信号
を出力する。When the connector 14 is reconnected in the state where the signal light output is shut down, the absolute reflection amount at the end face of the connector 14 is reduced to −40 dBm. Also, the relative reflection amount is -40 dB as in the normal case. Here, a threshold value comparison circuit 17 for comparing the absolute reflection amount with a predetermined threshold value.
Then, as shown in FIG. 3, it is detected that the absolute reflection amount is lower than the signal light output recovery threshold of −27.5 dBm, and a control signal for instructing to return the signal light output to the initial state is output. Further, in the threshold comparison circuit 22 that compares the relative reflection amount with a predetermined threshold value, it is detected that the relative reflection amount is below the signal light output control threshold −27.5 dB, as shown in FIG.
A control signal for instructing to return the signal light output to the initial state is output.
【0021】 信号光出力制御回路18は、閾値比較
回路17,22から出力される制御信号に応じて、光ア
ンプ12の信号光出力を当初の+15dBmになるように制
御する。なお、このときコネクタ14の端面における反
射量が減少しているので、絶対反射量は通常時と変わ
らない−25dBmとなり、相対反射量は−40dBとなる。The signal light output control circuit 18 controls the signal light output of the optical amplifier 12 to be the initial +15 dBm according to the control signals output from the threshold value comparison circuits 17 and 22. At this time, since the amount of reflection on the end face of the connector 14 has decreased, the absolute amount of reflection is -25 dBm, which is the same as in the normal state, and the amount of relative reflection is -40 dB.
【0022】以上説明したように、相対反射量に対する
信号光出力制御閾値−27.5dBは、絶対反射量に対する信
号光出力シャットダウン閾値−12.5dBmおよび信号光出
力回復閾値−27.5dBmと等価であり、絶対反射量および
相対反射量のいずれを用いても、コネクタ14の離脱・
接続に応じた信号光出力制御を行うことができる。ただ
し、相対反射量を用いた場合には1つの閾値で対応する
ことができるが、絶対反射量を用いた場合には2つの閾
値が必要になる。なお、絶対反射量を用いても、本実施
例のケースでは例えば−20dBm前後の信号光出力制御閾
値を設定すれば1つの閾値で対応することが可能である
が、これはシャットダウンレベルとコネクタ端面におけ
る反射量に左右されるので不可能な場合もある。As described above, the signal light output control threshold −27.5 dB with respect to the relative reflection amount is equivalent to the signal light output shutdown threshold −12.5 dBm and the signal light output recovery threshold −27.5 dBm with respect to the absolute reflection amount. Whether the reflection amount or the relative reflection amount is used, disconnection of the connector 14
The signal light output control according to the connection can be performed. However, one threshold value can be used when the relative reflection amount is used, but two threshold values are required when the absolute reflection amount is used. Even if the absolute reflection amount is used, in the case of the present embodiment, it is possible to deal with a single threshold value by setting a signal light output control threshold value of around −20 dBm, which is the shutdown level and the connector end face. It may be impossible because it depends on the amount of reflection at.
【0023】図4は、請求項2に記載の発明の実施例構
成を示すブロック図である。(a) は、反射光の絶対レベ
ル(dBm)から絶対反射量を検出する方法を用いた実施
例であり、(b) は反射光の信号光に対する相対レベル
(dB)から相対反射量を検出する方法を用いた実施例で
ある。FIG. 4 is a block diagram showing the configuration of an embodiment of the invention described in claim 2. In FIG. (a) is an embodiment using the method of detecting the absolute reflection amount from the absolute level (dBm) of the reflected light, and (b) is the relative reflection amount from the relative level (dB) of the reflected light to the signal light. It is an example using the method.
【0024】図4(a) において、高出力光送信部の主要
構成は、図1(a) の構成に加えて、信号光と異なる波長
を有するモニタ光を出力するモニタ光出力回路23と、
このモニタ光と信号光とを波長多重して光ファイバケー
ブル13に送出する光カプラ24とを備える。ただし、
光カプラ15はモニタ光の反射光を分岐する光カプラ2
5に替わり、反射光強度検出回路16はモニタ光の反射
光の光強度を検出する反射光強度検出回路26に替わ
り、閾値比較回路17は信号光出力制御閾値との比較を
行う閾値比較回路27に替わる。In FIG. 4 (a), the main components of the high-power optical transmitter are, in addition to the components of FIG. 1 (a), a monitor light output circuit 23 for outputting a monitor light having a wavelength different from that of the signal light,
An optical coupler 24 that wavelength-multiplexes the monitor light and the signal light and sends the multiplexed light to the optical fiber cable 13 is provided. However,
The optical coupler 15 is an optical coupler 2 that branches the reflected light of the monitor light.
5, the reflected light intensity detection circuit 16 is replaced by a reflected light intensity detection circuit 26 that detects the light intensity of the reflected light of the monitor light, and the threshold value comparison circuit 17 is a threshold value comparison circuit 27 that compares the signal light output control threshold value. Instead of.
【0025】図4(b) において、高出力光送信部の主要
構成は、図4(a) と同様の電気/光変換部11,光アン
プ12,光ファイバケーブル13,コネクタ14,光カ
プラ25,反射光強度検出回路26,信号光出力制御回
路18,モニタ光出力回路23および光カプラ24と、
さらに光ファイバケーブル13に挿入されてモニタ光出
力回路23からのモニタ光を分岐する光カプラ28と、
モニタ光の光強度を検出するモニタ光強度検出回路29
と、モニタ光強度と反射光強度とを比較して相対反射量
を検出する相対反射量検出回路21と、相対反射量と所
定の閾値(信号光出力制御閾値)とを比較し、その比較
結果に応じた制御信号を信号光出力制御回路18に出力
する閾値比較回路22とを備える。In FIG. 4B, the main configuration of the high-power optical transmission unit is the same as the electrical / optical conversion unit 11, the optical amplifier 12, the optical fiber cable 13, the connector 14, the optical coupler 25 shown in FIG. 4A. A reflected light intensity detection circuit 26, a signal light output control circuit 18, a monitor light output circuit 23 and an optical coupler 24,
Further, an optical coupler 28 which is inserted into the optical fiber cable 13 to branch the monitor light from the monitor light output circuit 23,
Monitor light intensity detection circuit 29 for detecting the light intensity of monitor light
And a relative reflection amount detection circuit 21 that detects the relative reflection amount by comparing the monitor light intensity and the reflected light intensity with the relative reflection amount and a predetermined threshold value (signal light output control threshold value). And a threshold comparison circuit 22 for outputting a control signal according to the above to the signal light output control circuit 18.
【0026】なお、請求項2におけるモニタ光送信手段
は、モニタ光出力回路23および光カプラ24に対応
し、反射量検出手段は、光カプラ25および反射光強度
検出回路26、あるいは光カプラ25,反射光強度検出
回路26,光カプラ28,モニタ光強度検出回路29お
よび相対反射量検出回路21に対応する。また、光信号
出力制御手段は、閾値比較回路27および信号光出力制
御回路18、あるいは閾値比較回路22および信号光出
力制御回路18に対応する。The monitor light transmitting means in claim 2 corresponds to the monitor light output circuit 23 and the optical coupler 24, and the reflection amount detecting means is the optical coupler 25 and the reflected light intensity detecting circuit 26, or the optical coupler 25, It corresponds to the reflected light intensity detection circuit 26, the optical coupler 28, the monitor light intensity detection circuit 29, and the relative reflection amount detection circuit 21. The optical signal output control means corresponds to the threshold comparison circuit 27 and the signal light output control circuit 18, or the threshold comparison circuit 22 and the signal light output control circuit 18.
【0027】以下、図5および図6を参照し、具体的数
値例を用いて各実施例の動作について説明する。 コネクタ14が接続されている通常時は、光アンプ
12からの信号光およびモニタ光出力回路23からのモ
ニタ光は、コネクタ14を介して伝送路ケーブル31に
送出される。このときの信号光強度を+15dBmとし、モ
ニタ光強度を−15dBmとする。コネクタ14が完全に接
続された状態では信号光およびモニタ光の反射は小さ
く、反射光強度検出回路26に検出されるモニタ光の反
射光強度(絶対反射量)は−55dBmである。すなわち、
相対反射量検出回路21に検出される相対反射量は−40
dBとなる。The operation of each embodiment will be described below with reference to FIGS. 5 and 6 by using specific numerical examples. When the connector 14 is connected normally, the signal light from the optical amplifier 12 and the monitor light from the monitor light output circuit 23 are sent to the transmission line cable 31 via the connector 14. The signal light intensity at this time is +15 dBm, and the monitor light intensity is -15 dBm. When the connector 14 is completely connected, reflection of the signal light and the monitor light is small, and the reflected light intensity (absolute reflection amount) of the monitor light detected by the reflected light intensity detection circuit 26 is -55 dBm. That is,
The relative reflection amount detected by the relative reflection amount detection circuit 21 is −40.
It becomes dB.
【0028】 通常時の状態でコネクタ14を離脱
すると、コネクタ14の端面で信号光およびモニタ光の
反射量が増加し、モニタ光の絶対反射量は−30dBmとな
る。また、相対反射量は−15dBとなる。ここで、絶対反
射量と所定の閾値との比較を行う閾値比較回路27で
は、図6に示すように絶対反射量が信号光出力制御閾値
−42.5dBmを越えたことが検出され、信号光出力の低下
を指示する制御信号を出力する。また、相対反射量と所
定の閾値との比較を行う閾値比較回路22では、図6に
示すように相対反射量が信号光出力制御閾値−27.5dBを
越えたことが検出され、信号光出力の低下を指示する制
御信号を出力する。When the connector 14 is detached in the normal state, the reflection amount of the signal light and the monitor light increases at the end face of the connector 14, and the absolute reflection amount of the monitor light becomes −30 dBm. The relative reflection amount is -15 dB. Here, in the threshold value comparison circuit 27 that compares the absolute reflection amount with a predetermined threshold value, it is detected that the absolute reflection amount exceeds the signal light output control threshold −42.5 dBm as shown in FIG. Output a control signal for instructing the decrease of. Further, in the threshold comparison circuit 22 which compares the relative reflection amount with a predetermined threshold value, it is detected that the relative reflection amount exceeds the signal light output control threshold −27.5 dB as shown in FIG. A control signal for instructing the decrease is output.
【0029】 信号光出力制御回路18は、閾値比較
回路27,22から出力される制御信号に応じて、光ア
ンプ12の信号光出力を−5dBmにシャットダウンさせ
る。なお、モニタ光出力はそのままである。また、この
ときコネクタ14の端面における反射量が増えているの
で、反射光強度検出回路26に検出されるモニタ光の反
射光強度(絶対反射量)は−30dBmとなる。相対反射量
は−15dBでコネクタ離脱時と変わらない。The signal light output control circuit 18 shuts down the signal light output of the optical amplifier 12 to −5 dBm in accordance with the control signals output from the threshold value comparison circuits 27 and 22. The monitor light output remains unchanged. Further, at this time, since the amount of reflection on the end surface of the connector 14 is increased, the reflected light intensity (absolute reflection amount) of the monitor light detected by the reflected light intensity detection circuit 26 is -30 dBm. The relative reflection is -15 dB, which is the same as when the connector is disconnected.
【0030】 信号光出力シャットダウン時の状態
でコネクタ14を再度接続すると、コネクタ14の端面
で信号光およびモニタ光の反射量が減少し、モニタ光の
反射光強度(絶対反射量)は通常時と同様に−55dBm
となる。また、相対反射量は−40dBとなる。ここで、絶
対反射量と所定の閾値との比較を行う閾値比較回路27
では、図6に示すように絶対反射量が信号光出力制御閾
値−42.5dBmを下回ったことが検出され、信号光出力を
当初の状態に戻すことを指示する制御信号を出力する。
また、相対反射量と所定の閾値との比較を行う閾値比較
回路22では、図6に示すように相対反射量が信号光出
力制御閾値−27.5dBを下回ったことが検出され、信号光
出力を当初の状態に戻すことを指示する制御信号を出力
する。When the connector 14 is reconnected in the state where the signal light output is shut down, the reflection amount of the signal light and the monitor light is reduced at the end face of the connector 14, and the reflected light intensity (absolute reflection amount) of the monitor light is different from that in the normal time. Similarly, −55 dBm
Becomes The relative reflection amount is -40 dB. Here, a threshold value comparison circuit 27 that compares the absolute reflection amount with a predetermined threshold value.
Then, as shown in FIG. 6, it is detected that the absolute reflection amount is below the signal light output control threshold −42.5 dBm, and a control signal for instructing to return the signal light output to the initial state is output.
Further, in the threshold comparison circuit 22 which compares the relative reflection amount with a predetermined threshold value, it is detected that the relative reflection amount is below the signal light output control threshold −27.5 dB as shown in FIG. A control signal for instructing to return to the initial state is output.
【0031】 信号光出力制御回路18は、閾値比較
回路27,22から出力される制御信号に応じて、光ア
ンプ12の信号光出力を当初の+15dBmになるように制
御する。なお、モニタ光出力はそのままである。The signal light output control circuit 18 controls the signal light output of the optical amplifier 12 to be the initial +15 dBm according to the control signals output from the threshold value comparison circuits 27 and 22. The monitor light output remains unchanged.
【0032】以上説明したように、本発明ではシャット
ダウン制御を行う信号光とは独立で一定レベルを維持す
るモニタ光を用いているので、絶対反射量および相対反
射量のいずれを用いても、1つの信号光出力制御閾値に
よりコネクタ14の離脱・接続に応じた信号光出力制御
を行うことができる。なお、相対反射量に対する信号光
出力制御閾値−27.5dBは、絶対反射量に対する信号光出
力制御閾値−42.5dBmと等価である。また、本発明では
シャットダウン制御時に、信号光出力を完全に遮断する
ようにしてもコネクタ再接続時の動作には影響はない。As described above, in the present invention, the monitor light that maintains a constant level independently of the signal light for performing the shutdown control is used. Therefore, even if the absolute reflection amount or the relative reflection amount is used, With one signal light output control threshold value, signal light output control according to disconnection / connection of the connector 14 can be performed. The signal light output control threshold of 27.5 dB for the relative reflection amount is equivalent to the signal light output control threshold of 42.5 dBm for the absolute reflection amount. Further, in the present invention, even if the signal light output is completely cut off during the shutdown control, the operation at the time of reconnecting the connector is not affected.
【0033】[0033]
【発明の効果】以上説明したように本発明は、信号光あ
るいはモニタ光のコネクタ端面からの反射光をモニタ
し、その反射光強度から絶対反射量あるいは相対反射量
を検出して閾値と比較することにより、コネクタの離脱
・接続を判定することができる。As described above, according to the present invention, the reflected light from the connector end face of the signal light or the monitor light is monitored, and the absolute reflection amount or the relative reflection amount is detected from the intensity of the reflected light and compared with the threshold value. This makes it possible to determine whether the connector is disconnected or connected.
【0034】したがって、このコネクタの離脱・接続に
応じて信号光出力を制御し、特にコネクタ離脱時に信号
光出力を自動的にシャットダウンすることにより、高レ
ベルの信号光が出力される事態を回避することができ
る。また、コネクタの再接続が行われたときにも、シャ
ットダウンさせていた信号光出力を自動的に回復させる
ことができる。Therefore, the signal light output is controlled according to the disconnection / connection of the connector, and in particular, the signal light output is automatically shut down when the connector is disconnected, thereby avoiding the situation where a high level signal light is output. be able to. Further, even when the connector is reconnected, the signal light output that has been shut down can be automatically restored.
【図1】請求項1に記載の発明の実施例構成を示すブロ
ック図。FIG. 1 is a block diagram showing a configuration of an embodiment of the invention described in claim 1.
【図2】図1の実施例におけるコネクタ着脱・接続時の
動作例を示す図。FIG. 2 is a diagram showing an operation example when a connector is attached / detached / connected in the embodiment of FIG.
【図3】図1の実施例におけるコネクタ着脱・接続時の
動作例を示す図。FIG. 3 is a diagram showing an operation example at the time of connector attachment / detachment / connection in the embodiment of FIG.
【図4】請求項2に記載の発明の実施例構成を示すブロ
ック図。FIG. 4 is a block diagram showing the configuration of an embodiment of the invention described in claim 2.
【図5】図4の実施例におけるコネクタ着脱・接続時の
動作例を示す図。FIG. 5 is a diagram showing an operation example at the time of attaching / detaching / connecting a connector in the embodiment of FIG.
【図6】図4の実施例におけるコネクタ着脱・接続時の
動作例を示す図。FIG. 6 is a diagram showing an operation example at the time of connector attachment / detachment / connection in the embodiment of FIG. 4;
11 電気/光変換部 12 光アンプ 13 光ファイバケーブル 14 コネクタ 15,19,24,25,28 光カプラ 16,26 反射光強度検出回路 17,22,27 閾値比較回路 18 信号光出力制御回路 20 信号光強度検出回路 21 相対反射量検出回路 23 モニタ光出力回路 29 モニタ光強度検出回路 11 Electrical / Optical Converter 12 Optical Amplifier 13 Optical Fiber Cable 14 Connector 15, 19, 24, 25, 28 Optical Coupler 16, 26 Reflected Light Intensity Detection Circuit 17, 22, 27 Threshold Comparison Circuit 18 Signal Optical Output Control Circuit 20 Signal Light intensity detection circuit 21 Relative reflection amount detection circuit 23 Monitor light output circuit 29 Monitor light intensity detection circuit
───────────────────────────────────────────────────── フロントページの続き (72)発明者 雨宮 正樹 東京都千代田区内幸町1丁目1番6号 日 本電信電話株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masaki Amamiya 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation
Claims (2)
ネクタを有し、光アンプを用いて増幅した信号光をその
コネクタを介して伝送路ケーブルに送出する高出力光送
信部において、 前記信号光が前記コネクタ端面で反射した反射光をモニ
タし、その反射量を検出する反射量検出手段と、 前記反射量が所定の閾値を下回るときには前記信号光出
力を所定レベルに設定し、前記反射量が所定の閾値を上
回るときには前記信号光出力を低下させる光信号出力制
御手段とを備えたことを特徴とする高出力光送信部の出
力シャットダウン制御装置。1. A high-power optical transmission unit that has a connector to which a transmission line cable is connected at an output end and sends out signal light amplified by an optical amplifier to the transmission line cable through the connector, Reflection amount detection means for monitoring the reflected light reflected by the end face of the connector and detecting the reflection amount, and setting the signal light output to a predetermined level when the reflection amount falls below a predetermined threshold, Is higher than a predetermined threshold value, the optical signal output control means for lowering the signal light output is provided.
ネクタを有し、光アンプを用いて増幅した信号光をその
コネクタを介して伝送路ケーブルに送出する高出力光送
信部において、 前記信号光とは異なる波長を有するモニタ光を前記信号
光に波長多重して送信するモニタ光送信手段と、 前記モニタ光が前記コネクタ端面で反射した反射光をモ
ニタし、その反射量を検出する反射量検出手段と、 前記反射量が所定の閾値を下回るときには前記信号光出
力を所定レベルに設定し、前記反射量が所定の閾値を上
回るときには前記光信号出力を低下させる光信号出力制
御手段とを備えたことを特徴とする高出力光送信部の出
力シャットダウン制御装置。2. A high-power optical transmission unit which has a connector to which a transmission line cable is connected at an output end, and which sends out signal light amplified by an optical amplifier to the transmission line cable through the connector. Monitor light transmitting means for wavelength-multiplexing and transmitting the monitor light having a wavelength different from that of the signal light, and a reflection amount for monitoring the reflected light reflected by the monitor light at the connector end face and detecting the reflection amount. A detection unit; and an optical signal output control unit that sets the signal light output to a predetermined level when the reflection amount is less than a predetermined threshold value and lowers the optical signal output when the reflection amount exceeds a predetermined threshold value. An output shutdown control device for a high-power optical transmitter.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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JP33067392A JP3209242B2 (en) | 1992-12-10 | 1992-12-10 | Output shutdown controller for high-power optical transmitter |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP33067392A JP3209242B2 (en) | 1992-12-10 | 1992-12-10 | Output shutdown controller for high-power optical transmitter |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH06177837A true JPH06177837A (en) | 1994-06-24 |
JP3209242B2 JP3209242B2 (en) | 2001-09-17 |
Family
ID=18235310
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JP33067392A Expired - Lifetime JP3209242B2 (en) | 1992-12-10 | 1992-12-10 | Output shutdown controller for high-power optical transmitter |
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JP (1) | JP3209242B2 (en) |
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