JPS58151081A - Laser power source circuit - Google Patents
Laser power source circuitInfo
- Publication number
- JPS58151081A JPS58151081A JP3311682A JP3311682A JPS58151081A JP S58151081 A JPS58151081 A JP S58151081A JP 3311682 A JP3311682 A JP 3311682A JP 3311682 A JP3311682 A JP 3311682A JP S58151081 A JPS58151081 A JP S58151081A
- Authority
- JP
- Japan
- Prior art keywords
- laser
- current
- prevented
- laser element
- output
- 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.)
- Pending
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
- H01S5/00—Semiconductor lasers
- H01S5/06—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
- H01S5/068—Stabilisation of laser output parameters
- H01S5/06825—Protecting the laser, e.g. during switch-on/off, detection of malfunctioning or degradation
Landscapes
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Optics & Photonics (AREA)
- Semiconductor Lasers (AREA)
Abstract
Description
【発明の詳細な説明】
力が一定と力るように自動制御するとともに、温度上昇
によるレーザー素子の破壊を防止するようにしたレーザ
ー電源回路に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laser power supply circuit that automatically controls a constant force and prevents a laser element from being destroyed due to temperature rise.
一般に半導体レーザーの出力は温度依存性が高く、安定
な出力を得るためにはレーザー出力の一部を検出して自
動制御を行う必要がある。ところが、半導体レーザーの
温度特性は負特性、すなわち温度が上昇すると出力が減
少する性質を有しており、そのため、従来の自動制御回
路においては温度上昇に比例してレーザー電流が増加し
つづけ、その度にレーザーの熱損失が上昇し、ついには
半導体レーザーの許容熱損失量を上まわり、半導体レー
ザーが破壊してしまうという問題があった。Generally, the output of a semiconductor laser is highly temperature dependent, and in order to obtain stable output, it is necessary to detect a portion of the laser output and perform automatic control. However, the temperature characteristics of semiconductor lasers are negative, that is, the output decreases as the temperature rises. Therefore, in conventional automatic control circuits, the laser current continues to increase in proportion to the temperature rise. There was a problem in that the heat loss of the laser increased over time, and eventually exceeded the allowable amount of heat loss for the semiconductor laser, resulting in destruction of the semiconductor laser.
本発明はこのような問題を解決しぐ故障の少ない半導体
レーザーの実現を可能にするレーザー電源回路を提供す
ることを目的としたものである。It is an object of the present invention to provide a laser power supply circuit that solves these problems and makes it possible to realize a semiconductor laser with fewer failures.
先ず、本発明によるレーザー電源回路の基本回路構成に
ついて説明する。First, the basic circuit configuration of the laser power supply circuit according to the present invention will be explained.
第1図は本発明によるレーザー電源回路の基本回路構成
を示すブロック図で、1は半導体からなるレーザー素子
、2はレーザー素子lのレーザー出力を検・出するため
の光検出器、3は光検出器2からの信号電圧と基準電圧
Eとを比較してレーザー出力を常に一定にする1自動制
御回路、4はレーザー素子1を駆動するための駆動回路
で、この駆動回路4には電源投入時の突入電流の発生を
防止する手段が設けられている。5は保護回路6よシの
指令および外部指令によシレーザー出力のON。FIG. 1 is a block diagram showing the basic circuit configuration of a laser power supply circuit according to the present invention, in which 1 is a laser element made of a semiconductor, 2 is a photodetector for detecting the laser output of the laser element 1, and 3 is an optical 1 is an automatic control circuit that compares the signal voltage from the detector 2 with the reference voltage E to keep the laser output constant; 4 is a drive circuit for driving the laser element 1; Means is provided to prevent the generation of inrush current at times. 5 turns on the laser output according to a command from the protection circuit 6 and an external command.
OFFあるいは出力制限を行う出力制御回路、7はレー
ザー素子1あるいはその近傍の温度を検出し、その検出
信号を保護回路6に入力する温度検出器である。An output control circuit 7 that turns off or limits the output is a temperature detector that detects the temperature of the laser element 1 or its vicinity and inputs the detection signal to the protection circuit 6.
第2図はこのような本発明の基本回路構成にもとついて
具体的に回路を構成した一例を示したもので、次に、こ
の第2図を参照しながら本発明を具体的に説明する。FIG. 2 shows an example of a specific circuit configuration based on the basic circuit configuration of the present invention.Next, the present invention will be specifically explained with reference to FIG. .
自動制御回路3は主に差動入力増幅器301で構成され
、一端子に接続された光検出器2による検出電圧が十端
子の基準電圧と比較されて常にレーザー出力が一定とな
るように駆動回路4を制御する。302は一端子に接続
された光検出器2に適当なバイアス電流を流すためのツ
ェナーダイオードである。駆動回路4におけるトランジ
スタ403のベースには抵抗401とコンデンサ402
より成る時定数回路が設けられ、これによりトランジス
タ403のベース電位の急激な立ち上りを防止し、電源
投入時、レーザー素子1に突入電流が流れこむのを防止
している。The automatic control circuit 3 mainly consists of a differential input amplifier 301, and a drive circuit so that the voltage detected by the photodetector 2 connected to one terminal is compared with the reference voltage of the ten terminals so that the laser output is always constant. Control 4. 302 is a Zener diode for passing an appropriate bias current to the photodetector 2 connected to one terminal. A resistor 401 and a capacitor 402 are connected to the base of the transistor 403 in the drive circuit 4.
A time constant circuit is provided, which prevents a sudden rise in the base potential of the transistor 403 and prevents a rush current from flowing into the laser element 1 when the power is turned on.
一方、採機回路6におけるコンパレーター601の十人
力の電位は温度検出器7の温度特性により温度に応じて
変化し、−人力の設定電位より十人力の電位が下がると
コンパレーター601の出力が反転して出力制御回路5
にレーザー素子1をOFFにするためのローレベルの指
令信号を出す。On the other hand, the electric potential of the comparator 601 in the sampling circuit 6 changes depending on the temperature due to the temperature characteristics of the temperature detector 7, and when the electric potential of the electric power falls below the set electric potential of the - electric power, the output of the comparator 601 changes. Inverted output control circuit 5
A low level command signal is issued to turn off the laser element 1.
出力制御回路5のANDゲート501は保護回路6の指
令信号と機器操作スイッチ等に連動した外部よりの指令
信号ANDヲとシリ後に接続されたトランジスタ502
,503,504をスイッチング動作させる。すなわち
、トランジスタ502のペース電位がハイレベルになる
とこのトランジスタ502はOFF −、Fランラスタ
503は0FF1)ランジスタ504はONとなシ駆動
回路4に電流を供給する。逆に、トランジスタ5020
ペース[位がローレベルになるとトランジスタ502は
ON、)ランジスタ503はON、)ランジスタ504
はOFFとなり、駆動回路4の電流を遮断する。なお、
抵抗506とコンデンサ507による時定数回路はトラ
ンジスタ5040ペース電位ノ急激な立ち上シを防き、
トランジスタ504のOFF −ON時の出力電流の急
激な増加を防止し、レーザー素子1への突入電流を防止
するためのものである。またトランジスタ502のエミ
ッタに接続したツェナーダイオード505は、ANDゲ
ート501の出力レベルとトランジスタ5o2のスイッ
チングレベル電圧をそろえるために設けられている。さ
らに、この実施飢ではトランジスタ503のコレクタを
直に接地した例を示したが、抵抗を介して接地するよう
にすれはトランジスタ504のスイッチング動作はよシ
完全なものとなり、したがって出力制限動作をより確実
に行なわせることができる。The AND gate 501 of the output control circuit 5 is connected to the command signal of the protection circuit 6 and the command signal AND from the outside linked to a device operation switch, etc., and then the transistor 502 is connected.
, 503, 504 are operated in a switching manner. That is, when the pace potential of the transistor 502 becomes high level, the transistor 502 is turned off, and the F run raster 503 is turned on (0FF1), and the transistor 504 is turned on to supply current to the drive circuit 4. Conversely, transistor 5020
When the pace becomes low level, transistor 502 turns on,) transistor 503 turns on,) transistor 504
is turned OFF, cutting off the current of the drive circuit 4. In addition,
The time constant circuit made up of the resistor 506 and the capacitor 507 prevents the transistor 5040 pace potential from rising rapidly.
This is to prevent a sudden increase in the output current when the transistor 504 is turned OFF and ON, and to prevent a rush current from flowing into the laser element 1. Furthermore, a Zener diode 505 connected to the emitter of the transistor 502 is provided to align the output level of the AND gate 501 and the switching level voltage of the transistor 5o2. Furthermore, in this implementation example, the collector of the transistor 503 is directly grounded, but if the collector is grounded through a resistor, the switching operation of the transistor 504 will be more complete, and the output limiting operation will be more effective. It can be done reliably.
以上説明したように、本発明のレーザー電源回路はレー
ザー出方を一定に制御する自動制御回路の他に、レーザ
ー素子の温度が所定値を越えた場合レーザーの駆動を停
止するがあるいはレーザーに供給する電流を制限するよ
うにしたので、従来のように温度上昇に比例してレーザ
ー電流が増加しつづけるようなことはなく、また、電源
投入時、レーザー素子に突入電流が流れることも防止す
るようにしたのでレーザー素子が破壊する確率と低くす
ることができる。As explained above, the laser power supply circuit of the present invention is not only an automatic control circuit that controls the output of the laser at a constant level, but also a circuit that stops driving the laser when the temperature of the laser element exceeds a predetermined value, or supplies power to the laser. Since the laser current is limited, the laser current does not continue to increase in proportion to the temperature rise as in the conventional case, and it also prevents rush current from flowing into the laser element when the power is turned on. This reduces the probability that the laser element will be destroyed.
したがって、本発明のレーザー電源回路によれば故障率
の低い長寿命の半導体レーザーを実現することが可能と
なる。Therefore, according to the laser power supply circuit of the present invention, it is possible to realize a long-life semiconductor laser with a low failure rate.
なお、本発明のレーザー電源回路は温度検出器7を他の
検出器におきかえれば、容易に他の要素の保護回路に適
用することも可能となる。Note that the laser power supply circuit of the present invention can be easily applied to protection circuits for other elements by replacing the temperature detector 7 with another detector.
【図面の簡単な説明】
第1図は本発明の基本回路構成を示すプロ、り図、第2
図は本発明にもとづく具体的回路の一例を示す図である
。
1・・・レーザー素子、2・・・光検出器、3・・・自
動制御回路、4・・・駆動回路、5・・・出力制御回路
、56・・・保護回路、7・・・温度検出器。[Brief explanation of the drawings] Figure 1 is a professional diagram showing the basic circuit configuration of the present invention;
The figure is a diagram showing an example of a specific circuit based on the present invention. DESCRIPTION OF SYMBOLS 1... Laser element, 2... Photodetector, 3... Automatic control circuit, 4... Drive circuit, 5... Output control circuit, 56... Protection circuit, 7... Temperature Detector.
Claims (1)
の自動制御回路を備えたレーザー電源回路において、半
導体レーザーの温度が所定値を越えたときに半導体レー
ザーに供給されるtIL流を制限する電流制限手段を設
けたことを特徴とするレーザー電源回路。 (2) 前記電流制限手段は電源投入時、レーザー素
子に突入電流が流れ込むのを防止する手段を含むことを
特徴とする特許請求の範囲第(1)項記動のレーザー電
源回路。[Claims] (11) In a laser power supply circuit equipped with an automatic control circuit for keeping the laser output of a semiconductor laser constant, the tIL flow supplied to the semiconductor laser when the temperature of the semiconductor laser exceeds a predetermined value. (2) A patent characterized in that the current limiting means includes means for preventing rush current from flowing into the laser element when the power is turned on. A laser power supply circuit according to claim (1).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3311682A JPS58151081A (en) | 1982-03-04 | 1982-03-04 | Laser power source circuit |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3311682A JPS58151081A (en) | 1982-03-04 | 1982-03-04 | Laser power source circuit |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS58151081A true JPS58151081A (en) | 1983-09-08 |
Family
ID=12377663
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3311682A Pending JPS58151081A (en) | 1982-03-04 | 1982-03-04 | Laser power source circuit |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS58151081A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6168324U (en) * | 1984-10-12 | 1986-05-10 | ||
JPS61105734A (en) * | 1984-10-29 | 1986-05-23 | Mazda Motor Corp | Audio set of automobile |
JP2013143759A (en) * | 2012-01-12 | 2013-07-22 | Fujitsu Ltd | Optical transmission device and optical transmission method |
JP5567176B1 (en) * | 2013-03-25 | 2014-08-06 | ミハル通信株式会社 | Semiconductor light emitting device controller |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS546703A (en) * | 1977-06-17 | 1979-01-19 | Mitsubishi Electric Corp | Laser equipment for optical communication |
JPS5727084A (en) * | 1980-07-25 | 1982-02-13 | Hitachi Ltd | Optical transmitter |
-
1982
- 1982-03-04 JP JP3311682A patent/JPS58151081A/en active Pending
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS546703A (en) * | 1977-06-17 | 1979-01-19 | Mitsubishi Electric Corp | Laser equipment for optical communication |
JPS5727084A (en) * | 1980-07-25 | 1982-02-13 | Hitachi Ltd | Optical transmitter |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6168324U (en) * | 1984-10-12 | 1986-05-10 | ||
JPS61105734A (en) * | 1984-10-29 | 1986-05-23 | Mazda Motor Corp | Audio set of automobile |
JP2013143759A (en) * | 2012-01-12 | 2013-07-22 | Fujitsu Ltd | Optical transmission device and optical transmission method |
JP5567176B1 (en) * | 2013-03-25 | 2014-08-06 | ミハル通信株式会社 | Semiconductor light emitting device controller |
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