JPS6235279B2 - - Google Patents
Info
- Publication number
- JPS6235279B2 JPS6235279B2 JP4575279A JP4575279A JPS6235279B2 JP S6235279 B2 JPS6235279 B2 JP S6235279B2 JP 4575279 A JP4575279 A JP 4575279A JP 4575279 A JP4575279 A JP 4575279A JP S6235279 B2 JPS6235279 B2 JP S6235279B2
- Authority
- JP
- Japan
- Prior art keywords
- output
- laser
- discharge current
- detection resistor
- laser tube
- 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.)
- Expired
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
- H01S3/10—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
- H01S3/131—Stabilisation of laser output parameters, e.g. frequency or amplitude by controlling the active medium, e.g. by controlling the processes or apparatus for excitation
- H01S3/134—Stabilisation of laser output parameters, e.g. frequency or amplitude by controlling the active medium, e.g. by controlling the processes or apparatus for excitation in gas lasers
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Optics & Photonics (AREA)
- Lasers (AREA)
Description
【発明の詳細な説明】
本発明はガスレーザ装置、特に光安定化制御回
路を具備したガスレーザ装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas laser device, and more particularly to a gas laser device equipped with a light stabilization control circuit.
従来、ガスレーザ装置では、光安定化を図るた
めにレーザ出力の一部を検出して、それが一定に
なるようにレーザ管の放電電流を制御する帰還回
路が用いられている。すなわち、第１図に示すよ
うに、直流電源１の負極出力端をレーザ管２のカ
ソードＫに接続し、正極出力端を電流制御用のト
ランジスタ３、電流検出抵抗４を通してレーザ管
２のアノードＡに接続する。一方、レーザ出力１
２の一部を光検出器５に入射し、その負荷抵抗６
の出力電圧を切換スイツチ７の固定接点ｃに接続
し、切換スイツチ７のもう一つの固定接点ｂには
電流検出抵抗４の出力電圧を接続し、スイツチ７
の可動片端子ａから、基準電源９の基準電圧との
差を増幅する比較増幅器８の一つの入力に接続
し、増幅器８の出力はトランジスタ３のベースに
接続している。 Conventionally, in order to achieve optical stabilization, gas laser devices have used a feedback circuit that detects a portion of the laser output and controls the discharge current of the laser tube so that it remains constant. That is, as shown in FIG. 1, the negative output terminal of the DC power supply 1 is connected to the cathode K of the laser tube 2, and the positive output terminal is connected to the anode A of the laser tube 2 through a current control transistor 3 and a current detection resistor 4. Connect to. On the other hand, laser output 1
2 is incident on the photodetector 5, and its load resistance 6
The output voltage of the current detection resistor 4 is connected to the fixed contact c of the changeover switch 7, and the output voltage of the current detection resistor 4 is connected to the other fixed contact b of the changeover switch 7.
is connected to one input of a comparator amplifier 8 that amplifies the difference between the movable terminal a and the reference voltage of the reference power source 9, and the output of the amplifier 8 is connected to the base of the transistor 3.
この第１図のガスレーザ装置の動作は、まず始
動時には、切換えスイツチ７の可動片は接点ｂに
接続され、レーザ管２の放電電流を検出する検出
抵抗４の出力電圧と基準電源９の差電圧を零にす
るように主比較増幅器８の出力によりトランジス
タ３のベースが定電流制御され、レーザ出力光１
２が或る程度安定になつた時点で切換スイツチ７
の可動片を接点ｃに切換え、レーザ光１２の一部
のレーザ光１３を光検出器５で検出し、光検出負
荷抵抗６の出力電圧と基準電源９との差電圧が零
になるように主比較増幅器８の出力によりトラン
ジスタ３レーザ出力のベースを制御している。 The operation of the gas laser apparatus shown in FIG. The base of the transistor 3 is controlled at a constant current by the output of the main comparator amplifier 8 so that the laser output light 1 becomes zero.
2 becomes stable to a certain extent, switch 7
The movable piece of is switched to contact c, a part of the laser beam 13 of the laser beam 12 is detected by the photodetector 5, and the voltage difference between the output voltage of the photodetection load resistor 6 and the reference power source 9 becomes zero. The output of the main comparison amplifier 8 controls the base of the laser output of the transistor 3.
このように、始動時に定電流制御で始まり、途
中で定出力制御に切換えるのは、初めから定出力
制御とすれば、レーザ管始動の初期には、一定の
光出力に対し多くの放電電流が流れるので、安定
出力に入るまでに電源その他にオーバーロードを
引起すためであるが、しかし、前記のようにスイ
ツチ７による切換に際し、接点ｂから接点ｃに切
換わるときに、一瞬可動片端子ａはどちらにも接
続されずに浮いた状態になり、その時主比較増幅
器８の出力電圧は急に増加し、トランジスタ３の
ベース電流は増加し、それとともにトランジスタ
３の内部抵抗は急激に低下し、レーザ管２の放電
流も急に増大し、レーザ管２およびトランジスタ
３の破損につながる。また、スイツチ７の切換わ
りが充分早く、上記のようなレーザ管２の破損に
到るような電流増大が防がれたとしても、若し、
ｃ接点の光検出器出力電圧が大き過ぎた場合、ト
ランジスタ３はオフとなり、レーザ管２の放電電
流が断たれるので放電は停止してしまう。 In this way, the reason why the laser tube starts with constant current control and then switches to constant output control during startup is because if constant output control is used from the beginning, a large amount of discharge current will be generated for a constant light output in the early stages of starting the laser tube. This is to cause an overload on the power supply and other components before stable output is achieved, but as mentioned above, when switching from contact b to contact c, the movable terminal a momentarily is not connected to either and becomes a floating state, at which time the output voltage of the main comparator amplifier 8 suddenly increases, the base current of the transistor 3 increases, and at the same time, the internal resistance of the transistor 3 decreases rapidly. The discharge current of the laser tube 2 also increases suddenly, leading to damage to the laser tube 2 and the transistor 3. Furthermore, even if the switch 7 is switched quickly enough to prevent the current increase that would lead to damage to the laser tube 2 as described above, if
If the photodetector output voltage of the c contact is too large, the transistor 3 is turned off and the discharge current of the laser tube 2 is cut off, so that the discharge stops.
本発明の目的は、前記の従来のレーザ装置の欠
点を改善し、定電流制御から光安定化制御に切換
えを行なう際に、前記のようなレーザ管またはト
ランジスタの破損か、またはレーザ管の放電停止
などを起らなくしたガスレーザ装置を提供するこ
とにある。 An object of the present invention is to improve the drawbacks of the conventional laser device described above, and to prevent damage to the laser tube or transistor or discharge of the laser tube when switching from constant current control to optical stabilization control. An object of the present invention is to provide a gas laser device that does not stop.
つぎに第２図に示した実施例により本発明を詳
細に説明する。第２図において、本発明では、従
来の第１図装置に対し、主比較増幅８とほぼ並列
に設けられた、同様の過電流抑圧比較増幅器２０
と過少電流防止用比較増幅器３０がつけ加えられ
ている。但し過電流用と過少電流用の比較増幅器
２０と３０は、主比較増幅器８と異なり、電流検
出抵抗４の出力電圧はスイツチを介さずに基準電
源２１，３１と比較する入力端子に直接接続され
ており、かつ、増幅器２０の出力とトランジスタ
３のベースとの間は、ベース側をアノードとする
逆流防止ダイオード２２を通して結合され、増幅
器３０の出力とトランジスタ３のベースとの間は
ベース側をカソードとする逆流防止ダイオード３
２を通して結合され、さらに増幅器８の出力とト
ランジスタ３のベースは抵抗１０とベース側をカ
ソードとした逆流防止ダイオード１１を通して結
合されている。 Next, the present invention will be explained in detail with reference to the embodiment shown in FIG. In FIG. 2, the present invention differs from the conventional device in FIG.
A comparator amplifier 30 for preventing undercurrent is added. However, the comparison amplifiers 20 and 30 for overcurrent and undercurrent are different from the main comparison amplifier 8 in that the output voltage of the current detection resistor 4 is directly connected to the input terminal for comparison with the reference power supplies 21 and 31 without going through a switch. The output of the amplifier 20 and the base of the transistor 3 are coupled through a backflow prevention diode 22 whose base side is the anode, and the output of the amplifier 30 and the base of the transistor 3 are coupled through the backflow prevention diode 22 whose base side is the cathode. Backflow prevention diode 3
Further, the output of the amplifier 8 and the base of the transistor 3 are coupled through a resistor 10 and a backflow prevention diode 11 whose base side is a cathode.
この第２図の回路動作について説明すると、ま
ず始動時の定電流制御、すなわち、スイツチ７の
可動片ａが接点ｂに接続されているときには、電
流検出抵抗出力電圧V2と主比較増幅器８の基準
電源９の出力電圧Ｖs1との差を増幅器８で増幅
し、抵抗１０、ダイオード１１を通してトランジ
スタ３のベースに供給し、差電圧が０になるよう
に制御している。この状態からスイツチ７を接点
ｃに切換える際に、可動片ａが一瞬浮いた状態に
おいては、主比較増幅器８の出力電圧は増加し、
トランジスタ３のベース電流も増大しようとする
が、それとともに電流検出抵抗４の出力電圧V2
も増加する。したがつて、今まで、過電流用比較
増幅器２０の基準電源２１の出力電圧Ｖs2より低
かつた出力電圧V2が基準電源Ｖs2に近づくと、増
幅器２０の出力電圧は減少し、したがつて、増大
した増幅器８の出力電圧は抵抗１０、ダイオード
１１，２２を通つて増幅器２０の出力端子に流れ
込み、トランジスタ３のベースに流れ込むのが抑
制され、結果として、比較増幅器８の一つの入力
オフによるレーザ管２の放電電流増大は抑圧され
る。 To explain the circuit operation shown in FIG. 2, first, constant current control at the time of starting, that is, when the movable piece a of the switch 7 is connected to the contact b, the current detection resistor output voltage V 2 and the main comparator amplifier 8 The difference with the output voltage V s1 of the reference power supply 9 is amplified by the amplifier 8 and supplied to the base of the transistor 3 through the resistor 10 and the diode 11, so that the difference voltage is controlled to be zero. When switching the switch 7 to contact c from this state, the output voltage of the main comparator amplifier 8 increases, while the movable piece a momentarily floats.
The base current of the transistor 3 also tries to increase, but at the same time the output voltage V 2 of the current detection resistor 4 increases.
will also increase. Therefore, until now, when the output voltage V 2 which was lower than the output voltage V s2 of the reference power supply 21 of the overcurrent comparison amplifier 20 approaches the reference power supply V s2 , the output voltage of the amplifier 20 decreases; Therefore, the increased output voltage of the amplifier 8 flows into the output terminal of the amplifier 20 through the resistor 10 and the diodes 11 and 22, and is suppressed from flowing into the base of the transistor 3. As a result, one input of the comparison amplifier 8 is turned off. An increase in the discharge current of the laser tube 2 caused by this is suppressed.
つぎに、切換スイツチ７が光検出器出力のｃ接
点側に切換わつた際に、光検出器の出力が基準電
圧Ｖs1に比べて大き過ぎた場合は、主比較増幅器
８の出力は小さくなり、それとともにトランジス
タ３のベース入力を減少し、放電電流もオフにな
ろうとするが、この場合の電流検出抵抗４の出力
電圧V2の出力低下により、過少電流用比較増幅
器３０の入力が減じようとする。そして、今まで
基準電圧３１の出力電圧Ｖs3より高かつたV2が基
準電圧Ｖs3より低下すると増幅器３０の出力は増
加し、この増加出力がダイオード３２を通してト
ランジスタ３のベースに供給され、トランジスタ
３の内部抵抗増大を妨げることにより、レーザ管
の放電電流オフを防止する。 Next, when the changeover switch 7 switches to the c-contact side of the photodetector output, if the output of the photodetector is too large compared to the reference voltage Vs1 , the output of the main comparison amplifier 8 becomes small. At the same time, the base input of the transistor 3 is decreased and the discharge current is also turned off, but in this case, the output voltage V 2 of the current detection resistor 4 is decreased, and the input of the undercurrent comparison amplifier 30 is likely to be decreased. shall be. Then, when V 2 , which has been higher than the output voltage V s3 of the reference voltage 31 until now, falls below the reference voltage V s3 , the output of the amplifier 30 increases, and this increased output is supplied to the base of the transistor 3 through the diode 32 , and the output voltage of the transistor 3 is increased. By preventing the increase in internal resistance of No. 3, the discharge current of the laser tube is prevented from turning off.
このように本発明では、従来の主比較増幅器に
並列な形式で、定電流制御のトランジスタのベー
ス電圧の異常な増大および減少を防止するための
過電流抑圧および過少電流防止用のそれぞれの比
較増幅器を追加することで、定電流制御から光安
定の制御への切換えの際に発生し勝ちな、レーザ
管の破損または発振停止などの不都合をなくし、
安全に切換え動作を行うという効果が得られる。 In this way, in the present invention, respective comparison amplifiers for overcurrent suppression and undercurrent prevention are installed in parallel with the conventional main comparison amplifier to prevent abnormal increases and decreases in the base voltage of constant current control transistors. By adding the
The effect of safely performing the switching operation can be obtained.
第１図は従来の定電流制御の光安定制御の切換
えスイツチをもつたガスレーザ装置の制御回路
図、第２図は本発明の一実施例の制御回路図であ
る。
１……レーザ電源、２……レーザ管、３……放
電電流制御トランジスタ、４……電流検出抵抗、
５……光検出器、６……光検出器負荷抵抗、７…
…切換えスイツチ、８…主比較増幅器、９，２
１，３１……比較増幅器の基準電源、１１，２
２，３２……逆流防止ダイオード、１２……レー
ザ出力光、１３……光検出器入射レーザ光、２０
……過電流抑圧比較増幅器、３０……過少電流防
止比較増幅器。
FIG. 1 is a control circuit diagram of a gas laser apparatus having a conventional constant current control and light stabilization control switching switch, and FIG. 2 is a control circuit diagram of an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Laser power supply, 2... Laser tube, 3... Discharge current control transistor, 4... Current detection resistor,
5...Photodetector, 6...Photodetector load resistance, 7...
...Selector switch, 8...Main comparator amplifier, 9,2
1, 31...Reference power supply for comparison amplifier, 11, 2
2, 32... Backflow prevention diode, 12... Laser output light, 13... Photodetector incident laser light, 20
...Overcurrent suppression comparison amplifier, 30...Undercurrent prevention comparison amplifier.
Claims (1)
供給するためのレーザ電源と、前記レーザ管と直
列に接続された、放電電流制御素子および電流検
出抵抗と、前記レーザ管の発生するレーザ光の一
部を入力とする光検出器と、前記電流検出抵抗の
検出電圧と前記光検出器の出力とをスイツチによ
り切換えて入力とし、この入力を基準電源と比較
し、前記放電電流制御素子に逆流阻止用ダイオー
ドを通して加えられる制御電圧を出力する主比較
増幅器と、前記電流検出抵抗出力端と放電電流制
御素子の間に介在され、それぞれ逆流防止ダイオ
ードを通して制御出力を前記放電電流制御素子に
出力する過電流抑圧および過少電流防止用の比較
増幅器をそれぞれ備えたことを特徴とするガスレ
ーザ装置。1 A gas laser tube, a laser power supply for supplying a discharge current of the laser tube, a discharge current control element and a current detection resistor connected in series with the laser tube, and a portion of the laser light generated by the laser tube. A photodetector receives the current detection resistor as an input, the detection voltage of the current detection resistor and the output of the photodetector are switched by a switch, and this input is compared with a reference power source, and the discharge current control element is used to prevent backflow. a main comparator amplifier that outputs a control voltage applied through a diode for overcurrent, and an overcurrent that is interposed between the output terminal of the current detection resistor and the discharge current control element, and outputs a control output to the discharge current control element through the respective backflow prevention diodes. A gas laser device characterized in that it is equipped with comparison amplifiers for suppression and undercurrent prevention.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4575279A JPS55138289A (en) | 1979-04-13 | 1979-04-13 | Gas laser device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4575279A JPS55138289A (en) | 1979-04-13 | 1979-04-13 | Gas laser device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS55138289A JPS55138289A (en) | 1980-10-28 |
| JPS6235279B2 true JPS6235279B2 (en) | 1987-07-31 |
Family
ID=12728028
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4575279A Granted JPS55138289A (en) | 1979-04-13 | 1979-04-13 | Gas laser device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS55138289A (en) |
-
1979
- 1979-04-13 JP JP4575279A patent/JPS55138289A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS55138289A (en) | 1980-10-28 |
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