JP2004259751A - Ld-pumped solid-state laser system and its operating method - Google Patents

Ld-pumped solid-state laser system and its operating method Download PDF

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JP2004259751A
JP2004259751A JP2003045905A JP2003045905A JP2004259751A JP 2004259751 A JP2004259751 A JP 2004259751A JP 2003045905 A JP2003045905 A JP 2003045905A JP 2003045905 A JP2003045905 A JP 2003045905A JP 2004259751 A JP2004259751 A JP 2004259751A
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value
laser device
state laser
solid
drive current
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JP4389451B2 (en
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Kazuaki Iwase
和明 岩瀬
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NEC Corp
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NEC Corp
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Abstract

<P>PROBLEM TO BE SOLVED: To provide an LD-pumped solid-state laser system that is put with a driving current limit for preventing the breakage of an LD, can control constantly its output power without requiring manual adjustment on an LD driving current or the limit value of a current even when the LD is deteriorated with time or a temperature variation occurs, and can automatically notify the exchange of the LD when the LD is deteriorated by outputting an alarm. <P>SOLUTION: A feedback circuit constituted of a control gain 12, the LD 2, a power monitor 4, and a feedback gain 14 constantly controls the output power of the LD-pumped solid-state laser system. When the output power of the laser system changes from its initial state due to the deterioration of the LD and the output range of the LD driving current for outputting constant output power exceeds an initial limit, a differentiation circuit 15 makes the constant control of the output power continuable by automatically adjusting the limit value of a current limiter 13. In addition, when the deterioration of the LD progresses and the adjustment of the limit value becomes impossible, the differentiation circuit 15 indicates the exchange of the LD by outputting the alarm. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、半導体レーザ励起固体レーザ装置に関し、とくに固体レーザ装置出力レーザパワー一定制御機能を持った半導体レーザ励起固体レーザ装置に関する。
【０００２】
【従来の技術】
半導体レーザ（ＬＤ）励起固体レーザ装置において、レーザ媒質励起用ＬＤがその発振特性に劣化を生じてきたり、あるいは周囲温度の変化した場合に、固体レーザ発振器のレーザ出力パワーが変動するという問題がある。従来は、人手によりＬＤ電流の調整を行ってパワー調整するか、あるいは自動パワー一定制御系を構成して行っていた。パワー一定制御を行う場合には、パワー特性がＬＤ電流に対して線形な領域で行う必要があるため、この線形領域で所望の一定出力パワーに対応するＬＤの設定電流値を調整していた。また、通常駆動電流の過入力によるＬＤの破壊を防止するために電流リミットを掛けている。
しかし、ＬＤの劣化が進行するとパワー特性が変化して初期設定のＬＤ電流値では同一のパワー出力が得られなくなる。このため、ＬＤ劣化の進行とともに設定電流値を徐々に増加させることによってパワーを一定に保持することができるが、設定電流値が初期設定の電流リミット値を越えた場合はその時点で最適なリミット値を更に高く設定し直す必要が生じる。さらにＬＤ劣化が進行したことによってリミットを調整してもパワー一定制御が不可能となった場合、ＬＤを交換すべきかどうかの判断を行う必要がある。従来はこのリミット調整あるいはＬＤ電流値調整を人手によって行っていたため、メンテナンス時には調整に熟練が必要であった。
出力の温度変動を生じたり劣化が生じているＬＤから常に所望の出力パワーを得るために、ＬＤの特性検出手段によって求めたＬＤ特性に基づいて目標値を補正して出力一定制御する技術が開示されている（例えば特許文献１参照）。この例は、固体レーザ出力ではなくＬＤ自身の出力一定制御であり、また、リミット調整の機能を備えておらず、リミットを調整してもパワー一定制御が不可能となった場合、ＬＤを交換すべきかどうかの判断を与える手段を備えていない。開示技術を用いてもなお固体レーザ励起用ＬＤのメンテナンスには熟練が必要である。
【０００３】
【特許文献１】
特開２０００−２９４８７１号公報（第６−９頁、図１）
【０００４】
【発明が解決しようとする課題】
本発明は、上記の課題に鑑みて成されたものであって、その目的とするところはＬＤ駆動電流出力のリミットを自動的に調整し、レーザパワー出力一定フィードバック制御を行うことができ、さらにＬＤ交換状態を指示するアラーム出力を備えた、ＬＤ調整に熟練の必要がなくなりメンテナンス性の向上を図ることができる半導体レーザ励起固体レーザ装置とその稼働方法を提供することにある。
【０００５】
【課題を解決するための手段】
本発明の半導体レーザ励起固体レーザ装置半導体レーザ（ＬＤ）を励起光源とする固体レーザ装置であって、ＬＤの駆動電流に制限を与える手段と、固体レーザ装置のレーザ出力がＬＤの駆動電流値によって自動的に一定となるように制御する手段と、固体レーザ装置のレーザ出力を一定にするために必要なＬＤの駆動電流値が、制限値を超える場合に、制限値を所要駆動電流値以上に増大させる手段、を備えることを特徴とする。
半導体レーザ励起固体レーザ装置が、さらに、制限値が予め設定した値を超える場合に警報を発する手段、を備える。
制限値は、レーザ出力をＬＤの駆動電流で微分した微分値が、微分値の最大値より所定の値だけ低下した値を与える駆動電流値である。
【０００６】
また本発明の半導体レーザ励起固体レーザ装置は、半導体レーザ（ＬＤ）を励起光源とする固体レーザ装置であって、固体レーザ装置のレーザ出力を検出する受光素子と、受光素子の出力が予め設定された目標値に自動的に一定となるようにＬＤの駆動電流を帰還制御する回路と、ＬＤの駆動電流に制限を与える電流リミット回路と、受光素子の出力をＬＤの駆動電流で微分し、微分値が微分値の最大値より所定の値だけ低下した値を与える駆動電流値を電流リミット回路の制限値として出力する微分回路を備えることを特徴とする。
半導体レーザ励起固体レーザ装置が、さらに、制限値が予め設定した値を超える場合に警報を発する回路を備える。
微分回路が、ＬＤの駆動電流値と微分値とを記憶するメモリを備える。
【０００７】
また本発明の半導体レーザ励起固体レーザ装置の稼働方法は、上記の半導体レーザ励起固体レーザ装置において、レーザ装置の起動時毎に、ＬＤの駆動電流を０から走引して、メモリのＬＤの駆動電流値と微分値の記憶データを書き換えるステップを含む。
また本発明の半導体レーザ励起固体レーザ装置の稼働方法は、上記の半導体レーザ励起固体レーザ装置において、適切な時間毎に、ＬＤの駆動電流を０から走引して、メモリのＬＤの駆動電流値と微分値の記憶データを書き換えるステップを含む。
【０００８】
【発明の実施の形態】
本発明の実施の形態を図面を参照して説明する。
本発明の半導体レーザ励起固体レーザ装置の概念装置構成を図１に示す。本構成は、レーザ発振器１とＬＤコントローラ６とで構成される。レーザ発振器１は、励起用ＬＤ２と、励起用ＬＤ２により励起されレーザ光を発振するレーザ共振器５０と、レーザ共振器が発振したをレーザ光５をさえぎるシャッタ３と、レーザ光５の出力の一部をモニタするパワーモニタ４から構成され、ＬＤコントローラ６は、パワーモニタ４の出力信号８をフィードバックしてＬＤ電流出力信号９を生成するフィードバック回路７を内蔵している。
【０００９】
フィードバック回路７の機能構成を図２に示す。フィードバック回路７は、指令パワーＰ０を電流値に変換する制御ゲイン１２、パワー入力にゲインを掛けるフィードバックゲイン１４、ＬＤ電流出力とパワー入力から微分波形を生成する微分回路１５、微分回路出力によりＬＤ電流出力リミット値を変化させるリミット回路１３、微分回路出力をモニタしてアラーム出力を行うアラーム回路１６から構成される。
【００１０】
本発明の半導体レーザ励起固体レーザ装置は、レーザ光５の出力パワーを一定に保つ機能と、励起ＬＤが劣化や温度変動によって出力特性が変化した場合に、励起ＬＤの駆動に設けられている電流リミットの値を自動的に調整する機能と、ＬＤ劣化が進行してリミット調整が不可能となった場合には、アラームを出力してＬＤ交換を指示する機能を備える。
【００１１】
次に本実施形態の動作を説明する。図３に励起ＬＤの駆動電流とレーザ共振器出力パワーの関係を示す。実線の曲線１０はＬＤに劣化を生じていない正常時の出力特性、破線１１はＬＤに劣化が起こり始めた異常時の出力特性を示す。正常時に所要のレーザ出力パワーＰ０を得るためにＬＤに印加する電流をＩ１とした時、制御ゲイン１２と、ＬＤ２と、パワーモニタ４と、フィードバックゲイン１４とが構成する帰還回路は印加電流をＩ２に増大して、異常時にも同一のパワーＰ０を出力するようにパワー一定制御の動作を行う。それは、図３に示すようにレーザパワー出力特性が初期状態１０からＬＤ劣化状態１１に変化してＬＤ電流出力範囲が初期リミットＩＬＩＭ１を越える場合にも自動的にリミットをＩＬＩＭ２に調整してパワー一定制御を続行できるからである。ＬＤ劣化が進行してリミット調整が不可能となった場合にはアラームを出力してＬＤ交換を指示できる。
【００１２】
さらに、ＬＤ劣化によるリミット制御とアラーム出力の動作を細かく説明する。まずレーザ発振器立上げ時にシャッタ３をクローズし、帰還回路のループを解き、リミット回路の電流制限を解除し、ＬＤ２の電流出力を０Ａから許容電流値までスキャンしながらパワーモニタ４によりパワー値を測定する（図４（Ａ））。この時に図３で示した微分回路１５では、ＬＤ電流出力とパワー入力から微分波形を生成する（図４（Ｂ））。正常時の微分出力波形１７を示した場合、リミット回路１３では、微分出力の定常出力状態又は最大値から一定値Δｐ‘低下したところをリミット値ＩＬＩＭ１としてＬＤ電流の制限を行う。ＬＤが劣化状態の異常時の出力特性に移行し、微分回路１５の出力が微分出力波形１８に移行した時、ＬＤ電流の制限を微分出力の定常出力状態又は最大値から一定値Δｐ‘低下したところをリミット値ＩＬＩＭ２とし、この制限電流内でパワー一定制御を続ける。
さらに、ＬＤの劣化が進み、リミット値がパワーフィードバック不可の領域となる場合すなわち、リミット電流値におけるレーザ出力が飽和に近づき、微分出力が予め定めた値のアラームレベルＰｌ‘より低下し、その点に対応する電流値に達した時、アラーム回路においてアラーム出力を行う。
以上により本発明の半導体レーザ励起固体レーザ装置では、パワー特性の変動がパワーフィードバック可能な領域にある場合には、自動的にリミット値が調整され、パワーフィードバック不可領域までパワーが変動した場合にはアラームが出力されるという処理が行われる。
【００１３】
本発明は、ＬＤ劣化によるパワー変動だけでなく、周囲温度の変化によるパワー変動に対しても同様にリミット調整を行うことができるため、レーザパワー出力特性の測定を随時行うことにより、温度変化が大きい環境においても適用が可能である。
【００１４】
【発明の効果】
以上説明したように、本発明の半導体レーザ励起固体レーザ装置は、レーザパワーのフィードバックを行うことができ、ＬＤ電流出力のリミットを自動的に調整し、アラーム出力によりＬＤ交換状態も明確となるため、調整に熟練の必要がなくなりメンテナンス性の向上を図ることができる。
【００１５】
【図面の簡単な説明】
【図１】本発明の半導体レーザ励起固体レーザ装置の概念的な構成を示す図である。
【図２】本発明の半導体レーザ励起固体レーザ装置が備えるフィードバック回路のブロック図である。
【図３】レーザパワー出力特性を示す図である。
【図４】本発明の半導体レーザ励起固体レーザ装置のフィードバック回路が備える微分回路の微分出力を示す図である。
【符号の説明】
１ レーザ発振器
２ ＬＤ
３ シャッタ
４ パワーモニタ
５ レーザ光
６ コントローラ[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a semiconductor laser-excited solid-state laser device, and more particularly to a semiconductor laser-excited solid-state laser device having a function of controlling the output laser power of the solid-state laser device.
[0002]
[Prior art]
In a semiconductor laser (LD) pumped solid-state laser device, there is a problem that the laser output power of the solid-state laser oscillator fluctuates when the oscillation characteristic of the laser medium pumping LD deteriorates or the ambient temperature changes. . Conventionally, the power is adjusted by manually adjusting the LD current, or an automatic power constant control system is configured. When the power constant control is performed, it is necessary to perform the power characteristic in a linear region with respect to the LD current. Therefore, the set current value of the LD corresponding to a desired constant output power is adjusted in this linear region. Further, a current limit is applied to prevent the LD from being destroyed due to excessive input of the normal drive current.
However, as the deterioration of the LD progresses, the power characteristics change and the same power output cannot be obtained with the initially set LD current value. For this reason, the power can be kept constant by gradually increasing the set current value with the progress of the LD deterioration, but when the set current value exceeds the initially set current limit value, the optimum limit is set at that time. The value needs to be set higher. Further, if the power is not controlled even if the limit is adjusted due to the progress of the LD deterioration, it is necessary to determine whether or not the LD should be replaced. Conventionally, the limit adjustment or the LD current value adjustment is manually performed, so that the adjustment requires skill in maintenance.
In order to always obtain a desired output power from an LD in which output temperature fluctuation or deterioration has occurred, a technique of correcting a target value based on LD characteristics obtained by LD characteristic detection means and performing constant output control is disclosed. (For example, see Patent Document 1). In this example, the LD is not a solid-state laser output but a constant output control of the LD itself. The LD is not provided with a limit adjustment function. There is no means to give a decision on whether to do so. Even if the disclosed technology is used, skill is required for maintenance of the LD for solid-state laser excitation.
[0003]
[Patent Document 1]
JP-A-2000-294871 (page 6-9, FIG. 1)
[0004]
[Problems to be solved by the invention]
The present invention has been made in view of the above problems, and a purpose thereof is to automatically adjust a limit of an LD drive current output, and to perform laser power output constant feedback control. An object of the present invention is to provide a semiconductor laser-excited solid-state laser device having an alarm output for instructing an LD replacement state and requiring no skill in LD adjustment and improving maintainability, and an operating method thereof.
[0005]
[Means for Solving the Problems]
A semiconductor laser-excited solid-state laser device according to the present invention is a solid-state laser device using a semiconductor laser (LD) as an excitation light source, wherein a means for limiting a drive current of the LD and a laser output of the solid-state laser device are controlled by an LD drive current value. Means for automatically controlling the laser output of the solid-state laser device to be constant, and when the drive current value of the LD required to maintain the laser output of the solid-state laser device exceeds the limit value, the limit value is increased to a required drive current value or more. Means for increasing.
The semiconductor laser-excited solid-state laser device further includes means for issuing an alarm when the limit value exceeds a preset value.
The limit value is a drive current value at which a differential value obtained by differentiating the laser output with the drive current of the LD gives a value lower than the maximum differential value by a predetermined value.
[0006]
Further, the semiconductor laser-excited solid-state laser device of the present invention is a solid-state laser device using a semiconductor laser (LD) as an excitation light source, wherein a light-receiving element for detecting a laser output of the solid-state laser device and an output of the light-receiving element are preset. A feedback control circuit for the LD drive current so as to automatically become constant at the target value, a current limit circuit for limiting the LD drive current, and differentiating the output of the light receiving element with the LD drive current. A differential circuit is provided which outputs a drive current value that gives a value whose value is lower than the maximum value of the differential value by a predetermined value as a limit value of the current limit circuit.
The semiconductor laser-excited solid-state laser device further includes a circuit that issues an alarm when the limit value exceeds a preset value.
The differentiating circuit includes a memory that stores the drive current value and the differential value of the LD.
[0007]
Further, the operating method of the semiconductor laser-excited solid-state laser device according to the present invention is the semiconductor laser-excited solid-state laser device described above, wherein the drive current of the LD is swept from 0 every time the laser device is started to drive the LD of the memory. And rewriting the stored data of the current value and the differential value.
In addition, the operating method of the semiconductor laser-excited solid-state laser device according to the present invention is the semiconductor laser-excited solid-state laser device described above, wherein the drive current of the LD is swept from 0 at an appropriate time and the drive current value of the LD of the memory is increased. And rewriting the stored data of the differential value.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a conceptual configuration of a semiconductor laser pumped solid-state laser device according to the present invention. This configuration includes a laser oscillator 1 and an LD controller 6. The laser oscillator 1 includes an excitation LD 2, a laser resonator 50 that is excited by the excitation LD 2 and oscillates a laser beam, a shutter 3 that blocks the laser beam 5 when the laser resonator oscillates, and one of the outputs of the laser beam 5. The LD controller 6 includes a feedback circuit 7 that feeds back an output signal 8 of the power monitor 4 to generate an LD current output signal 9.
[0009]
FIG. 2 shows a functional configuration of the feedback circuit 7. The feedback circuit 7 includes a control gain 12 for converting the command power P 0 into a current value, a feedback gain 14 for multiplying the power input by a gain, a differentiating circuit 15 for generating a differential waveform from the LD current output and the power input, and an LD based on the differential circuit output. It comprises a limit circuit 13 for changing the current output limit value and an alarm circuit 16 for monitoring the output of the differentiation circuit and outputting an alarm.
[0010]
The semiconductor laser-pumped solid-state laser device of the present invention has a function of keeping the output power of the laser beam 5 constant and a current provided for driving the pump LD when its output characteristics change due to deterioration or temperature fluctuation. It has a function of automatically adjusting the limit value and a function of outputting an alarm and instructing LD replacement when the limit deterioration becomes impossible due to progress of LD deterioration.
[0011]
Next, the operation of the present embodiment will be described. FIG. 3 shows the relationship between the drive current of the pump LD and the output power of the laser resonator. A solid line curve 10 indicates the output characteristic in a normal state where the LD has not deteriorated, and a broken line 11 indicates the output characteristic in an abnormal state where the LD has started to deteriorate. When the current applied to the LD to obtain the required laser output power P 0 under normal conditions is I 1 , the feedback circuit formed by the control gain 12, the LD 2, the power monitor 4, and the feedback gain 14 applies the applied current. the increases in I 2, performs the operation of the power constant control so as to output the same power P 0 to abnormality. That is, as shown in FIG. 3, even when the laser power output characteristic changes from the initial state 10 to the LD deterioration state 11 and the LD current output range exceeds the initial limit ILIM1 , the limit is automatically adjusted to ILIM2. This is because the constant power control can be continued. If the limit adjustment becomes impossible due to the progress of the LD deterioration, an alarm is output and the LD replacement can be instructed.
[0012]
Further, the operation of limit control and alarm output due to LD deterioration will be described in detail. First, when the laser oscillator is started, the shutter 3 is closed, the loop of the feedback circuit is released, the current limit of the limit circuit is released, and the power value is measured by the power monitor 4 while scanning the current output of the LD 2 from 0 A to the allowable current value. (FIG. 4A). At this time, the differentiating circuit 15 shown in FIG. 3 generates a differential waveform from the LD current output and the power input (FIG. 4B). When the differential output waveform 17 in the normal state is shown, the limit circuit 13 limits the LD current as the limit value I LIM1 when the differential output is in the steady output state or when the differential output decreases by a fixed value Δp ′ from the maximum value. When the LD shifts to the output characteristic at the time of abnormality in the deteriorated state and the output of the differentiating circuit 15 shifts to the differential output waveform 18, the LD current limit is reduced by a constant value Δp ′ from the steady output state or the maximum value of the differential output. However, the limit value is ILIM2, and the constant power control is continued within this limit current.
Further, when the deterioration of the LD progresses and the limit value becomes an area where power feedback is impossible, that is, the laser output at the limit current value approaches saturation, and the differential output drops below the alarm level Pl 'of a predetermined value. When the current value corresponding to is reached, the alarm circuit outputs an alarm.
As described above, in the semiconductor laser-pumped solid-state laser device of the present invention, the limit value is automatically adjusted when the fluctuation of the power characteristic is in the power feedback available region, and when the power fluctuates to the power feedback impossible region, A process of outputting an alarm is performed.
[0013]
According to the present invention, not only power fluctuations due to LD deterioration but also power fluctuations due to changes in ambient temperature can be similarly adjusted. Therefore, by measuring laser power output characteristics as needed, temperature fluctuations can be reduced. Applicable even in large environments.
[0014]
【The invention's effect】
As described above, the semiconductor laser-excited solid-state laser device of the present invention can perform feedback of laser power, automatically adjust the limit of the LD current output, and also clarify the LD replacement state by the alarm output. This eliminates the need for skill in adjustment, thereby improving maintainability.
[0015]
[Brief description of the drawings]
FIG. 1 is a diagram showing a conceptual configuration of a semiconductor laser pumped solid-state laser device of the present invention.
FIG. 2 is a block diagram of a feedback circuit provided in the semiconductor laser-excited solid-state laser device of the present invention.
FIG. 3 is a diagram showing laser power output characteristics.
FIG. 4 is a diagram showing a differential output of a differentiating circuit provided in a feedback circuit of the semiconductor laser pumped solid-state laser device of the present invention.
[Explanation of symbols]
1 Laser oscillator 2 LD
3 shutter 4 power monitor 5 laser beam 6 controller

Claims (8)

半導体レーザ（ＬＤ）を励起光源とする固体レーザ装置であって、
前記ＬＤの駆動電流に制限を与える手段と、
前記固体レーザ装置のレーザ出力が前記ＬＤの駆動電流値によって自動的に一定となるように制御する手段と、
前記固体レーザ装置のレーザ出力を一定にするために必要な前記ＬＤの駆動電流値が、前記制限値を超える場合に、前記制限値を前記所要駆動電流値以上に増大させる手段、
を備えることを特徴とする半導体レーザ励起固体レーザ装置。A solid-state laser device using a semiconductor laser (LD) as an excitation light source,
Means for limiting the drive current of the LD;
Means for controlling the laser output of the solid-state laser device to be automatically constant by the drive current value of the LD,
A means for increasing the limit value to the required drive current value or more, when the drive current value of the LD required for keeping the laser output of the solid-state laser device constant exceeds the limit value;
A semiconductor laser-excited solid-state laser device comprising: 前記半導体レーザ励起固体レーザ装置が、
さらに、前記制限値が予め設定した値を超える場合に警報を発する手段、
を備えることを特徴とする請求項１に記載の半導体レーザ励起固体レーザ装置。The semiconductor laser pumped solid-state laser device,
Further, a means for issuing an alarm when the limit value exceeds a preset value,
The semiconductor laser pumped solid-state laser device according to claim 1, further comprising: 前記制限値は、
前記レーザ出力を前記ＬＤの駆動電流で微分した微分値が、前記微分値の最大値より所定の値だけ低下した値を与える駆動電流値である、
ことを特徴とする請求項１に記載の半導体レーザ励起固体レーザ装置。The limit value is:
A differential value obtained by differentiating the laser output with a drive current of the LD is a drive current value that gives a value lower than the maximum value of the differential value by a predetermined value.
The solid-state laser device according to claim 1, wherein: 半導体レーザ（ＬＤ）を励起光源とする固体レーザ装置であって、
前記固体レーザ装置のレーザ出力を検出する受光素子と、
前記受光素子の出力が予め設定された目標値に自動的に一定となるように前記ＬＤの駆動電流を帰還制御する回路と、
前記ＬＤの駆動電流に制限を与える電流リミット回路と、
前記受光素子の出力を前記ＬＤの駆動電流で微分し、前記微分値が前記微分値の最大値より所定の値だけ低下した値を与える駆動電流値を前記電流リミット回路の制限値として出力する微分回路、
を備えることを特徴とする半導体レーザ励起固体レーザ装置。A solid-state laser device using a semiconductor laser (LD) as an excitation light source,
A light-receiving element for detecting a laser output of the solid-state laser device,
A circuit that feedback-controls the drive current of the LD so that the output of the light receiving element automatically becomes constant at a preset target value;
A current limit circuit for limiting a drive current of the LD;
Differentiation for differentiating an output of the light receiving element with a drive current of the LD and outputting a drive current value that gives a value obtained by lowering the differential value by a predetermined value from a maximum value of the differential value as a limit value of the current limit circuit. circuit,
A semiconductor laser-excited solid-state laser device comprising: 前記半導体レーザ励起固体レーザ装置が、
さらに、前記制限値が予め設定した値を超える場合に警報を発する回路、
を備えることを特徴とする請求項４に記載の半導体レーザ励起固体レーザ装置。The semiconductor laser pumped solid-state laser device,
Further, a circuit for issuing an alarm when the limit value exceeds a preset value,
The semiconductor laser-pumped solid-state laser device according to claim 4, comprising: 前記微分回路が、
前記ＬＤの駆動電流値と前記微分値とを記憶するメモリ、
を備えることを特徴とする請求項４に記載の半導体レーザ励起固体レーザ装置。The differentiating circuit,
A memory for storing a drive current value of the LD and the differential value,
The semiconductor laser-pumped solid-state laser device according to claim 4, comprising: 請求項６に記載の半導体レーザ励起固体レーザ装置において、
前記レーザ装置の起動時毎に、前記ＬＤの駆動電流を０から走引して、前記メモリの前記ＬＤの駆動電流値と前記微分値の記憶データを書き換えるステップ、
を含むことを特徴とする半導体レーザ励起固体レーザ装置の稼働方法。The semiconductor laser pumped solid-state laser device according to claim 6,
Each time the laser device is started, sweeping the drive current of the LD from 0, and rewriting storage data of the drive current value and the differential value of the LD in the memory;
A method for operating a semiconductor laser-excited solid-state laser device, comprising: 請求項６に記載の半導体レーザ励起固体レーザ装置において、
適切な時間毎に、前記ＬＤの駆動電流を０から走引して、前記メモリの前記ＬＤの駆動電流値と前記微分値の記憶データを書き換えるステップ、
を含むことを特徴とする半導体レーザ励起固体レーザ装置の稼働方法。The semiconductor laser pumped solid-state laser device according to claim 6,
Rewriting storage data of the LD drive current value and the differential value of the memory by sweeping the drive current of the LD from 0 every appropriate time;
A method for operating a semiconductor laser-excited solid-state laser device, comprising:
JP2003045905A 2003-02-24 2003-02-24 Semiconductor laser pumped solid state laser device and operation method thereof Expired - Fee Related JP4389451B2 (en)

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EP1681750A1 (en) * 2005-01-17 2006-07-19 Fanuc Ltd Laser oscillator and method of estimating the lifetime of a pump light source
JP2006210812A (en) * 2005-01-31 2006-08-10 Sumitomo Electric Ind Ltd Circuit and method for light output control
CN100385756C (en) * 2006-05-19 2008-04-30 北京航空航天大学 Stable light source light power output apparatus with full optical fiber structure
JP2008130848A (en) * 2006-11-21 2008-06-05 Mitsutoyo Corp Laser frequency stabilizing apparatus, and laser frequency stabilizing method
JP2008141054A (en) * 2006-12-04 2008-06-19 Mitsutoyo Corp Apparatus, method, and program for stabilizing laser frequency
US7889772B2 (en) 2006-04-25 2011-02-15 Mitsubishi Electric Corporation Laser oscillator apparatus and power supply apparatus therefor, and control method therefor
WO2012010688A3 (en) * 2010-07-22 2012-03-15 Coherent Gmbh Modulation method for diode-laser pumped lasers
CN103825185A (en) * 2014-03-25 2014-05-28 深圳市杰普特电子技术有限公司 Laser output device and control method thereof
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1681750A1 (en) * 2005-01-17 2006-07-19 Fanuc Ltd Laser oscillator and method of estimating the lifetime of a pump light source
JP2006210812A (en) * 2005-01-31 2006-08-10 Sumitomo Electric Ind Ltd Circuit and method for light output control
US7889772B2 (en) 2006-04-25 2011-02-15 Mitsubishi Electric Corporation Laser oscillator apparatus and power supply apparatus therefor, and control method therefor
CN100385756C (en) * 2006-05-19 2008-04-30 北京航空航天大学 Stable light source light power output apparatus with full optical fiber structure
JP2008130848A (en) * 2006-11-21 2008-06-05 Mitsutoyo Corp Laser frequency stabilizing apparatus, and laser frequency stabilizing method
JP2008141054A (en) * 2006-12-04 2008-06-19 Mitsutoyo Corp Apparatus, method, and program for stabilizing laser frequency
WO2012010688A3 (en) * 2010-07-22 2012-03-15 Coherent Gmbh Modulation method for diode-laser pumped lasers
US8351477B2 (en) 2010-07-22 2013-01-08 Coherent Gmbh Modulation method for diode-laser pumped lasers
JP2014116346A (en) * 2012-12-06 2014-06-26 Panasonic Corp Laser oscillator
CN103825185A (en) * 2014-03-25 2014-05-28 深圳市杰普特电子技术有限公司 Laser output device and control method thereof

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