JPS62203393A - Laser diode optical output stabilizing circuit - Google Patents

Laser diode optical output stabilizing circuit

Info

Publication number
JPS62203393A
JPS62203393A JP61045199A JP4519986A JPS62203393A JP S62203393 A JPS62203393 A JP S62203393A JP 61045199 A JP61045199 A JP 61045199A JP 4519986 A JP4519986 A JP 4519986A JP S62203393 A JPS62203393 A JP S62203393A
Authority
JP
Japan
Prior art keywords
laser diode
output
diode
circuit
optical 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
Application number
JP61045199A
Other languages
Japanese (ja)
Inventor
Nobuyuki Hashimoto
信幸 橋本
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Citizen Watch Co Ltd
Original Assignee
Citizen Watch Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Citizen Watch Co Ltd filed Critical Citizen Watch Co Ltd
Priority to JP61045199A priority Critical patent/JPS62203393A/en
Priority to US07/021,333 priority patent/US4787087A/en
Priority to EP87103094A priority patent/EP0235813A3/en
Publication of JPS62203393A publication Critical patent/JPS62203393A/en
Pending legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01SDEVICES 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
    • H01S5/00Semiconductor lasers
    • H01S5/04Processes or apparatus for excitation, e.g. pumping, e.g. by electron beams
    • H01S5/042Electrical excitation ; Circuits therefor
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01SDEVICES 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
    • H01S5/00Semiconductor lasers
    • H01S5/06Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/068Stabilisation of laser output parameters
    • H01S5/0683Stabilisation of laser output parameters by monitoring the optical output parameters
    • H01S5/06835Stabilising during pulse modulation or generation

Landscapes

  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Optics & Photonics (AREA)
  • Dot-Matrix Printers And Others (AREA)
  • Laser Beam Printer (AREA)
  • Exposure Or Original Feeding In Electrophotography (AREA)
  • Facsimile Scanning Arrangements (AREA)
  • Semiconductor Lasers (AREA)

Abstract

PURPOSE:To output a laser beam by stabilizing the beam according to simple circuit construction, and to utilize the laser diode for various apparatus by turning the laser diode on and off by a method wherein output of the laser diode is detected always, and voltages being proportional to optical output are stored. CONSTITUTION:A laser beams radiated from a laser diode 30 is detected by the photo diode 28 of an output stabilizing circuit, and a voltage generated in an electric resistor 32 connected in series to the diode 28 thereof is stored in a unidirectionally charging circuit consisting of a diode 34, an electric resistor 38 and a capacitor 36. Output from the unidirectionally charging circuit thereof is amplified by an operational amplifier 26, and a constant-current source circuit supplying a voltage to the diode 30 and consisting of an electric resistor 52, a capacitor 50 and a transistor 24 is driven by output of the operational amplifier 26. Moreover, a negative feedback circuit consisting of an electric resistor 42 and a capacitor 40 is provided to the operational amplifier 26 to stabilize action. Construction is simplified, and output of the laser beam can be stabilized.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は近年注目を集めているレーザーダイオードを用
いたレーザービームプリンタにおLる、レーザーダイオ
ード光出力安定化に関するものである。
DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to stabilization of laser diode light output in a laser beam printer using a laser diode, which has been attracting attention in recent years.

〔従来の技術〕[Conventional technology]

レーザーダイオードは光出力の温度依存性が大きいため
光出力を常に検出しフィードバックをかげて光出力を安
定化する事が一般に行なわれている。しかしレーザープ
リンタなどの場合においては、レーザーダイオードを点
滅して用いる事により光出力がOになっている期間があ
るためその間において光出力が0になる前の状態を記憶
して次のレーザーダイオードの点燈時の光出力安定化に
備える必要があり、一般には前記手段としてサンプルホ
ールド回路が用いられている。
Since the optical output of a laser diode is highly dependent on temperature, it is common practice to constantly detect the optical output and use feedback to stabilize the optical output. However, in the case of laser printers, etc., there is a period when the optical output is 0 due to the use of a blinking laser diode, so during that period, the state before the optical output became 0 is memorized and the next laser diode is used. It is necessary to prepare for stabilizing the light output when the light is turned on, and a sample and hold circuit is generally used as the means.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

しかしながらサンプルホールド回路は一般に回路構成が
複雑になったり、サンプリングパルスを出力するタイミ
ングがくるってしまうとレーザーダイオードを破損して
しまう恐れがあるなどの問題点があった。
However, sample-and-hold circuits generally have problems such as a complicated circuit configuration and the risk of damaging the laser diode if the timing of outputting the sampling pulse is delayed.

本発明は、ダイオードとコンデンサで構成された一方向
充電回路を用いる事により、簡単な回路構成で、レーザ
ーダイオード非点燈期間に前回の点燈時におけるレーザ
ーダイオードの光出力状態を記憶し、次回のレーザーダ
イオード点燈時の光出力安定化に備える事のできろ回路
を提供することを目的とするものである。
By using a one-way charging circuit composed of a diode and a capacitor, the present invention uses a simple circuit configuration to memorize the optical output state of the laser diode at the time of the previous lighting during the period when the laser diode is not lit, and to use it next time. The object of the present invention is to provide a circuit that can prepare for stabilizing the optical output when the laser diode is turned on.

〔問題点を解決するための手段〕[Means for solving problems]

上記問題点を解決するため本発明はレーザーダイオード
と該レーザーダイオードから出射されたレーザー光を検
知するフォトダイオードと該フォトダイオードに発生し
た光出力に比例した電圧を記憶するためのコンデンサと
抵抗とダイオードよりなる一方向充電回路と該一方向性
充電回路の電圧を入力するオペアンプと該オペアンプの
出力をゲート入力しレーザーダイオードの電源となる定
を流源トランジスタより構成してなるレーザーダイオー
ド光の安定化回路を提供する。
In order to solve the above problems, the present invention provides a laser diode, a photodiode for detecting laser light emitted from the laser diode, a capacitor, a resistor, and a diode for storing a voltage proportional to the optical output generated in the photodiode. Stable laser diode light consisting of a unidirectional charging circuit, an operational amplifier that inputs the voltage of the unidirectional charging circuit, and a current source transistor that inputs the output of the operational amplifier to the gate and serves as a power source for the laser diode. Provides a conversion circuit.

〔実施例〕〔Example〕

次に図面を用いて本発明の詳細な説明する。 Next, the present invention will be explained in detail using the drawings.

第2図は本発明の原理図で、レーザーダイオード10か
ら出射したレーザー光12は、フォトダイオード14で
光出力を検知され抵抗16によりレーザーダイオード1
0の光出力に比例した電圧が発生し、その電圧をダイオ
ード18、コンデンサ20を用いた一方向充電回路で充
電することにより、レーザーダイオード100元出力が
Oとなっても、前回のレーザーダイオード点燈時の光出
力状態をコンデンサ20に電圧として記憶保持する事が
できる。
FIG. 2 is a diagram showing the principle of the present invention, in which a laser beam 12 emitted from a laser diode 10 has its optical output detected by a photodiode 14 and is connected to the laser diode 1 by a resistor 16.
A voltage proportional to the optical output of 0 is generated, and by charging that voltage with a one-way charging circuit using a diode 18 and a capacitor 20, even if the laser diode output of 100 becomes O, the previous laser diode point The light output state when the light is turned on can be stored in the capacitor 20 as a voltage.

第1図は本発明における実施例であり、レーザーダイオ
ード光出力安定化点滅回路の回路図である。PNP型ト
ランジスタ24はオペアンプ26の出力によりベースに
バイアス電圧が印加され、該バイアス電圧が一定の間は
定電流源を構成している。フォトダイオード28は、レ
ーザーダイオード300元出力を常に検知し、抵抗62
によりレーザーダイオード60の光出力に比例した電圧
を発生する。オペフッ1260反転入力端子には適当な
基準電圧■、が印加されている。今レーザーダイオード
60の光出力がある設定値より太きくなると、フォトダ
イオード28の検出電流が増加し抵抗62に発生する電
圧が高くなり、ダイオード34を介してオペアンプ26
の正転入力端子に印加される電圧が高くなり、オペアン
プ26の出力電圧が高(なる。その結果PNP型トラン
ジスタ240ベース電圧が高くなり、コレクタ電流が減
少し、レーザーダイオード600光出力が小さくなる方
向に向う。逆にレーザーダイオード60の光出力がある
設定値より小さくなると、今と逆の経過により、レーザ
ーダイオード600元出力は大きくなる方向に向う。こ
の様にして第1図の回路はレーザーダイオード60の光
出力を安定化する作用を持つ。
FIG. 1 is an embodiment of the present invention, and is a circuit diagram of a laser diode light output stabilizing blinking circuit. A bias voltage is applied to the base of the PNP transistor 24 by the output of the operational amplifier 26, and while the bias voltage is constant, it constitutes a constant current source. The photodiode 28 always detects the laser diode 300 yuan output, and the resistor 62
A voltage proportional to the optical output of the laser diode 60 is generated. An appropriate reference voltage (2) is applied to the inverting input terminal of the operation switch 1260. When the optical output of the laser diode 60 becomes thicker than a certain set value, the detection current of the photodiode 28 increases, the voltage generated in the resistor 62 becomes high, and the voltage is applied to the operational amplifier 26 via the diode 34.
As a result, the voltage applied to the normal input terminal of the operational amplifier 26 increases.As a result, the base voltage of the PNP transistor 240 increases, the collector current decreases, and the optical output of the laser diode 600 decreases. Conversely, when the optical output of the laser diode 60 becomes smaller than a certain set value, the optical output of the laser diode 600 increases in the opposite direction.In this way, the circuit shown in FIG. It has the effect of stabilizing the optical output of the diode 60.

NPN型トランジスタ44は、そのコレクタとエミッタ
の間にレーザーダイオード60を挾みこみ、トランジス
タ440ベース電圧が高電位になるとトランジスタ44
がON状態となり、本来レーザーダイオード60に流れ
る電流がトランジスタ44のコレクタ、エミッタ間に流
れ込み、レーザーダイオード60は消灯する。したがっ
て、TTLクロックパルス48をトランジスタ440ベ
ースに印加する事により、レーザーダイオード60を点
滅させる事ができる。この時、ダイオード64とコンデ
ンサ66は一方向充電回路を構成しているので、レーザ
ーダイオード非点燈時において、以前の点燈時の状態を
コンデンサ36の充電電圧として保持できる。抵抗68
はコンデンサ66に保持された充電電圧を放電する際の
時定数をきめるものである。抵抗68の値が大きいと放
電の時定数が長くなり、記憶保持できる時間が長くなり
、レーザーダイオード30が長時間清澄していても、次
の点燈時の光出力安定化に備えることができる。しかし
外気温が変化するなどしてレーザーダイオード60の光
出力が震動した時の光出力安定化回路の応答性は低下し
てゆく。抵抗68の値が小さいと今とまったく逆の事が
いえる。
The NPN transistor 44 has a laser diode 60 interposed between its collector and emitter, and when the base voltage of the transistor 440 becomes a high potential, the transistor 44
turns on, the current that originally flows through the laser diode 60 flows between the collector and emitter of the transistor 44, and the laser diode 60 turns off. Therefore, applying a TTL clock pulse 48 to the base of transistor 440 can cause laser diode 60 to blink. At this time, since the diode 64 and the capacitor 66 constitute a one-way charging circuit, when the laser diode is not turned on, the previous state when the laser diode is turned on can be maintained as the charging voltage of the capacitor 36. resistance 68
determines the time constant when discharging the charging voltage held in the capacitor 66. If the value of the resistor 68 is large, the time constant of discharge becomes long, and the time that can be stored is extended, so that even if the laser diode 30 remains clear for a long time, it can prepare for stabilizing the light output at the next lighting time. . However, when the optical output of the laser diode 60 fluctuates due to changes in the outside temperature, etc., the responsiveness of the optical output stabilizing circuit decreases. If the value of the resistor 68 is small, the exact opposite is true.

レーザープリンタの場合は、各トントラインの打ち始め
に、タイミング信号として一定時間レーザーダイオード
を点燈させるので、最低各ドツトライフ間の周期の間記
憶保持できれば良い。オペアンブ26の正転入力端子の
インピーダンスは通常100MΩ程度と有限の値を持つ
ため、場合によってはオペアンプの正転入力端子の入力
インピーダンスで前記の放電時定数を決定し、抵抗38
をはふく事も可能である。
In the case of a laser printer, since a laser diode is turned on for a certain period of time as a timing signal at the beginning of printing each dot line, it is sufficient that the data can be stored for at least the period between each dot life. Since the impedance of the normal input terminal of the operational amplifier 26 usually has a finite value of about 100 MΩ, in some cases, the above-mentioned discharge time constant is determined by the input impedance of the normal input terminal of the operational amplifier, and the resistor 38
It is also possible to wipe the

コンデンサ40は抵抗42とともに負帰還回路を構成し
ている。これは、レーザーダイオード30の非点燈時に
コンデンサ66の充電電圧が除徐に抵Tしてゆくため、
オペアンプ26の出力が変動してゆくのを防ぐために設
けられている。
The capacitor 40 and the resistor 42 constitute a negative feedback circuit. This is because the charging voltage of the capacitor 66 gradually decreases when the laser diode 30 is not lit.
This is provided to prevent the output of the operational amplifier 26 from fluctuating.

本実施例においてはコンデンサ66は0.033μFコ
ンデンサ40は0.033μF、抵抗38は省略しレー
ザーダイオード30の常時点燈時における光出力を約3
.5mWに設定した場合、約100μsのレーザーダイ
オードの点燈時間が最初にあれば、その後約2000μ
sの非点燈時間があっても次のレーザーダイオードの点
燈時に3.5mWの光出力を安定的に出力した。また−
20°Cから+80℃においでレーザーダイオード60
0元出力の変動幅は±2%以内であった。また1℃/ 
Sec程度の外気温の変化に対してもレーザーダイオー
ド600元出力は十分安定に保たれた。またレーザーダ
イオード60を20 Mllz、 Duty 50%で
高速点滅してもレーザーダイオード60の光出力は設定
光出力に対し安定に保たれた。
In this embodiment, the capacitor 66 is 0.033 μF, the capacitor 40 is 0.033 μF, the resistor 38 is omitted, and the optical output when the laser diode 30 is constantly lit is approximately 3 μF.
.. When set to 5mW, if the initial lighting time of the laser diode is about 100μs, then about 2000μs
Even if there was a non-lighting time of s, a light output of 3.5 mW was stably output when the laser diode was next turned on. Also-
Laser diode 60 at 20°C to +80°C
The fluctuation range of the zero-source output was within ±2%. Also 1℃/
The laser diode output of 600 yuan remained sufficiently stable even with changes in the outside temperature of about 200 sec. Further, even when the laser diode 60 was blinked at a high speed of 20 Mllz and a duty of 50%, the optical output of the laser diode 60 was kept stable with respect to the set optical output.

また光出力検出用フォトダイオードはレーザーダイオー
ドパッケージに内蔵されているものを用いたが、外部に
別のフォトダイオードを設置してレーザーダイオードの
光を検出しても良い。
Further, although the photodiode for detecting the light output was built in the laser diode package, another photodiode may be installed outside to detect the light from the laser diode.

〔発明の効果〕〔Effect of the invention〕

以上の説明で明らかなように本発明によれば、簡単な回
路構成でレーザーダイオードの光出力を安定化させなが
らレーザーダイオードを点滅させる事が可能となる。こ
の回路はレーザープリンタのみでなく、レーザーダイオ
ードを光出力安定化して点滅させる事の必要なすべての
機器において使用する事が可能である。またレーザーダ
イオードのみでなくLEDにおいても同様の事が可能ど
なる。
As is clear from the above description, according to the present invention, it is possible to blink the laser diode while stabilizing the optical output of the laser diode with a simple circuit configuration. This circuit can be used not only in laser printers, but also in all devices that require a laser diode to stabilize its light output and blink. Moreover, the same thing can be done not only with laser diodes but also with LEDs.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は本発明におけるレーザーダイオード光出力安定
化点滅回路の回路図、第2図は本発明におけるレーザー
ダイオードの光出力に比例した電圧信号の保持回路の原
理を示す回路図。 10.30・・・・・・レーザーダイオード、12・・
・・・・レーザー光、 14.28・・・・・・フォトダイオード、16.22
.32.68.42.46.52・・・・・・電気抵抗
、 18.64・・・・・・ダイオード、 20.66.40.50・旧・・コンデンサ、24.4
4・・・・・・トランジスタ、26・・・・・・オペア
ンプ、 48・・・・・・TTLクロックパルス。 第2図 第1図
FIG. 1 is a circuit diagram of a laser diode optical output stabilizing blinking circuit according to the present invention, and FIG. 2 is a circuit diagram showing the principle of a holding circuit for a voltage signal proportional to the optical output of a laser diode according to the present invention. 10.30... Laser diode, 12...
...Laser light, 14.28...Photodiode, 16.22
.. 32.68.42.46.52... Electric resistance, 18.64... Diode, 20.66.40.50 Old... Capacitor, 24.4
4...transistor, 26...op-amp, 48...TTL clock pulse. Figure 2 Figure 1

Claims (2)

【特許請求の範囲】[Claims] (1)レーザーダイオードと該レーザーダイオードから
の光を検出するフォトダイオードと該フォトダイオード
と直列に接続した抵抗素子と該抵抗素子に発生する電圧
を保持するダイオードとコンデンサと抵抗からなる一方
向充電回路と該一方向充電回路の出力を入力するオペア
ンプと該オペアンプの出力を入力とする定電流源回路と
からなるレーザーダイオード光出力安定化回路。
(1) A unidirectional charging circuit consisting of a laser diode, a photodiode that detects light from the laser diode, a resistor connected in series with the photodiode, a diode that holds the voltage generated in the resistor, a capacitor, and a resistor. A laser diode optical output stabilization circuit comprising: an operational amplifier inputting the output of the one-way charging circuit; and a constant current source circuit inputting the output of the operational amplifier.
(2)オペアンプはコンデンサと抵抗からなる負帰還回
路を有することを特徴とする特許請求の範囲第1項記載
のレーザーダイオード光出力安定化回路。
(2) The laser diode optical output stabilizing circuit according to claim 1, wherein the operational amplifier has a negative feedback circuit consisting of a capacitor and a resistor.
JP61045199A 1986-03-04 1986-03-04 Laser diode optical output stabilizing circuit Pending JPS62203393A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP61045199A JPS62203393A (en) 1986-03-04 1986-03-04 Laser diode optical output stabilizing circuit
US07/021,333 US4787087A (en) 1986-03-04 1987-03-03 Circuit for driving a laser diode
EP87103094A EP0235813A3 (en) 1986-03-04 1987-03-04 Circuit for driving a laser diode

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP61045199A JPS62203393A (en) 1986-03-04 1986-03-04 Laser diode optical output stabilizing circuit

Publications (1)

Publication Number Publication Date
JPS62203393A true JPS62203393A (en) 1987-09-08

Family

ID=12712596

Family Applications (1)

Application Number Title Priority Date Filing Date
JP61045199A Pending JPS62203393A (en) 1986-03-04 1986-03-04 Laser diode optical output stabilizing circuit

Country Status (1)

Country Link
JP (1) JPS62203393A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7814716B2 (en) 2003-02-10 2010-10-19 Moffatt Andrew M Construction unit mounting system
CN114498290A (en) * 2022-04-14 2022-05-13 武汉博激世纪科技有限公司 Semiconductor laser therapeutic instrument control system and method

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58158051A (en) * 1982-03-15 1983-09-20 Toshiba Corp Controller for stabilizing output of semiconductor laser oscillator
JPS59163724A (en) * 1983-03-08 1984-09-14 林原 健 Conducting and interrupting device near zero potential of accurrent

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58158051A (en) * 1982-03-15 1983-09-20 Toshiba Corp Controller for stabilizing output of semiconductor laser oscillator
JPS59163724A (en) * 1983-03-08 1984-09-14 林原 健 Conducting and interrupting device near zero potential of accurrent

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7814716B2 (en) 2003-02-10 2010-10-19 Moffatt Andrew M Construction unit mounting system
US7980032B2 (en) 2003-02-10 2011-07-19 Moffatt Andrew M Construction unit mounting system
CN114498290A (en) * 2022-04-14 2022-05-13 武汉博激世纪科技有限公司 Semiconductor laser therapeutic instrument control system and method

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