JPS6181677A - Light receiving apparatus - Google Patents
Light receiving apparatusInfo
- Publication number
- JPS6181677A JPS6181677A JP59203105A JP20310584A JPS6181677A JP S6181677 A JPS6181677 A JP S6181677A JP 59203105 A JP59203105 A JP 59203105A JP 20310584 A JP20310584 A JP 20310584A JP S6181677 A JPS6181677 A JP S6181677A
- Authority
- JP
- Japan
- Prior art keywords
- photodiode
- output
- voltage
- operational amplifier
- current
- 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
- 238000005375 photometry Methods 0.000 claims description 12
- 238000001514 detection method Methods 0.000 abstract description 2
- 238000000034 method Methods 0.000 description 10
- 238000010586 diagram Methods 0.000 description 7
- 238000005259 measurement Methods 0.000 description 6
- 229910052732 germanium Inorganic materials 0.000 description 3
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 description 3
- 230000003287 optical effect Effects 0.000 description 3
- 239000003990 capacitor Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/02—Details
- H01L31/02016—Circuit arrangements of general character for the devices
- H01L31/02019—Circuit arrangements of general character for the devices for devices characterised by at least one potential jump barrier or surface barrier
Landscapes
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Electromagnetism (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Light Receiving Elements (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は受光装置、特に発光装置からの光量の受光方式
において、微弱光測定領域の洩れ電流の影響を低減し、
かつ、大光測領域への拡大が可能な測光方式をもった受
光装置に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention reduces the influence of leakage current in a weak light measurement area in a light receiving device, particularly in a light receiving method for the amount of light from a light emitting device.
The present invention also relates to a light receiving device having a photometry method that can be expanded to a large photometry area.
半導体レーザの光出力は高出力化される傾向にあり、そ
の結果発光装置からの先出−力の低レベルから高レベル
にわたるものを測定する必要がある。The optical output of semiconductor lasers tends to be increased, and as a result, it is necessary to measure the initial output power from a light emitting device ranging from a low level to a high level.
その測定に用いる受光装置は、短波長帯域にはシリコン
が、また長波長帯域にはゲルマニウムが一般的に用いら
れる。ところが、これらの受光装置は温度変化によって
暗電流の変化が激しく、それを用いた受光装置において
は暗電流対策が重要な課題となっている。従来の測光回
路方式には二つのものがあり、第1の方式は第3図に示
される回路で、フォトダイオード31にROの付加抵抗
32を接続し、フォトダイオード感度を上げるために電
源33からVot 、 VO2、、、、、の逆バイアス
を印加し、抵抗32に流れる光電流Ishをl5h−R
o= Vの形で端子34で取り出す。なお第3図におい
て、35はフォトダイオードに入射される光を表わし、
端子36と34の間にはVol 、 、、 、 、 V
o5の電圧がかかる。The light receiving device used for this measurement is generally made of silicon for short wavelength bands and germanium for long wavelength bands. However, in these light receiving devices, the dark current changes drastically due to temperature changes, and dark current countermeasures have become an important issue in light receiving devices using such light receiving devices. There are two conventional photometric circuit systems. The first method is the circuit shown in Figure 3, in which an additional resistor 32 of RO is connected to the photodiode 31, and a power supply 33 is connected to the photodiode 31 to increase the sensitivity. Vot, VO2, . . . are applied with reverse bias, and the photocurrent Ish flowing through the resistor 32 is
It is taken out at terminal 34 in the form of o=V. In addition, in FIG. 3, 35 represents the light incident on the photodiode,
Vol, , , , V between terminals 36 and 34
o5 voltage is applied.
第2の方式は第4図の回路に示され、この方式では、等
価付加抵抗がきわめて小であるオペアンプ(OP−AM
P) 42を用い、 l5h−Rf# e、の形で光
強度を取り出す。なお、第4図において、41はフォト
ダイオード、43はフォトダイオードに入射される光、
44はRfの抵抗、Ishは光が入ったときダイオード
41からオペアンプを経て端子45に流れる電流を表わ
す。The second method is shown in the circuit of FIG.
P) 42 and extract the light intensity in the form l5h-Rf#e. In addition, in FIG. 4, 41 is a photodiode, 43 is light incident on the photodiode,
44 represents a resistor Rf, and Ish represents a current flowing from the diode 41 to the terminal 45 via the operational amplifier when light enters.
フォトダイオードの光出力特性は実際の値と異なること
、すなわち一般には受光センサーの特性によづて外部に
光出力を電気的に取り出したときに出力変化があり、本
来の値から離れた値が得られることは知られている。ま
た、例えば受光センサー(フォトダイオード)にゲルマ
ニウムを用いたとき、ゲルマニウムの暗電流(洩れ電流
)が温度によって激しく変化することも知られている。The light output characteristics of a photodiode differ from the actual value. In other words, in general, there is a change in the output when the light output is electrically extracted to the outside depending on the characteristics of the light receiving sensor, and a value far from the original value may occur. It is known that it can be obtained. It is also known that when germanium is used, for example, in a light receiving sensor (photodiode), the dark current (leakage current) of germanium changes drastically depending on the temperature.
第5図は第3図と第4図のフォトダイオードにおける電
圧−電流特性を示す図で、同図において、横軸は順電圧
と逆電圧、縦軸は順電流と逆電流、0.2,4,6.8
を付した曲線はQmW 、 2mW 、 。FIG. 5 is a diagram showing the voltage-current characteristics of the photodiodes shown in FIGS. 3 and 4. In the figure, the horizontal axis is forward voltage and reverse voltage, and the vertical axis is forward current and reverse current. 4,6.8
The curves marked with QmW, 2mW, .
、、8IIIWの光量の光出力を示し、曲線aは第3図
の回路、線すは第4図の回路における光出力の電圧−電
流の関係を示す。第3図に示す方式においては、逆バイ
アスVo5のあたりで直線限界を超えて飽和に向い、更
には逆バイアスVo1では温度変化による暗電流(第5
図に砂地を付して示す領域)の影響が大で、微弱測光時
のS/N比が極端に悪くなる、すなわち、光出力レベル
が小さくてフォトダイオードの結晶自体がもっている暗
電流にほぼ等しい値のとき、光出力量を測量できない問
題がある。しかし、逆バイアスが印加されているので大
光測領域では感度が良いという利点がある。. In the method shown in Fig. 3, the linear limit is exceeded and saturation occurs around the reverse bias Vo5, and furthermore, at the reverse bias Vo1, the dark current (5
(area shown with a sandy area in the figure), and the S/N ratio during weak photometry becomes extremely poor.In other words, the light output level is small and the dark current of the photodiode crystal itself is large. When the values are equal, there is a problem that the amount of light output cannot be measured. However, since a reverse bias is applied, it has the advantage of good sensitivity in large photometry areas.
第4図に示す方式においては、Δei(V)の状態で(
第511)、大略1shに近いところで直線限界が延び
てくるが、特性の悪いフォトダイオードにおいては直線
限界が早(来るという問題がある。In the method shown in Fig. 4, in the state of Δei (V) (
No. 511), the linear limit is extended at approximately 1sh, but there is a problem that the linear limit occurs quickly in photodiodes with poor characteristics.
しかし、微弱光強度の場合は、逆バイアス印加がないの
で、温度変化に対して暗電流の影響が少なく、計測精度
が良くなる利点がある。However, in the case of weak light intensity, since no reverse bias is applied, there is less influence of dark current on temperature changes, which has the advantage of improving measurement accuracy.
本発明は、上記問題点を解消した受光装置を提供するも
ので、その手段は、フォトダイオードを用いる測光にお
いて、フォトダイオードの出力側にはフォトダイオード
からの光電流を増幅する第1のオペアンプが接続され、
フォトダイオードの接地側には、測光出力を絶対値で検
波し、利得を合わせて逆バイアス電圧に変換しフォトダ
イオードに供給する第2のオペアンプが接続されたこと
を特徴とする受光装置によってなされる。The present invention provides a light receiving device that solves the above problems, and its means include, in photometry using a photodiode, a first operational amplifier for amplifying the photocurrent from the photodiode on the output side of the photodiode. connected,
This is accomplished by a photodetector characterized in that a second operational amplifier is connected to the ground side of the photodiode, which detects the photometric output in absolute value, adjusts the gain, converts it into a reverse bias voltage, and supplies the voltage to the photodiode. .
上記の受光装置は、フォトダイオードに逆バイアスを印
加すると微弱光領域で暗電流の影響を無視しえないこと
、また逆バイアス印加がないと直線限界領域が早(来て
計測範囲が小になること、の従来方式双方のそれぞれの
問題点を解決し、より高精度な検出を実現するものであ
る。In the above photodetector, if a reverse bias is applied to the photodiode, the influence of dark current cannot be ignored in the weak light region, and if no reverse bias is applied, the linear limit region will quickly reach (and the measurement range will become smaller). This method solves the problems of both conventional methods and achieves more accurate detection.
以下、図面を参照して本発明の実施例を詳細に説明する
。Embodiments of the present invention will be described in detail below with reference to the drawings.
本発明実施例を第1図の回路図を参照して説明する。図
において点線で凹むフォトダイオードlはRshの内部
抵抗をもつもので、フォトダイオードに入射する光は符
号2を付した矢印で示す。なお、Rf1+ Chは第1
のオペアンプA1に並列に設けた抵抗と容量、A2は第
2のオペアンプ、Rfz +01、 Cf2はオペアン
プに並列に設けた抵抗、ダイオード、容量、Vlhは可
変抵抗、Riと D2はオペアンプ八2に直列に接続さ
れた抵抗とダイオード、をそれぞれ示す。フォトダイオ
ードの出力側に接続された第1のオペアンプA1には、
フォトダイオード1からの光電流Ishに対して−(I
sh xRh )(V)の電圧出力が現われ、信号電流
が電圧に変化される。Rhの値は、フォトダイオードの
内部抵抗Rshに比べ小なる方が有利であるが、微弱光
測光では出力電圧を大きくとる目的でRfを大きくとる
とオペアンプ^lの雑音電圧が(1+ Rfx / R
sh)倍に拡大されることに注意する。図において、3
は出力端子、4はダイオードを示し、Cb 、Cfzは
ダビング容量で、リギングや雑音低減用のものである。An embodiment of the present invention will be described with reference to the circuit diagram of FIG. In the figure, a photodiode l recessed by a dotted line has an internal resistance of Rsh, and light incident on the photodiode is indicated by an arrow labeled 2. Note that Rf1+ Ch is the first
A2 is the second operational amplifier, Rfz +01, Cf2 is the resistor, diode, and capacitor connected in parallel to the operational amplifier, Vlh is a variable resistor, Ri and D2 are connected in series with the operational amplifier A1, and A2 is the second operational amplifier. A resistor and a diode connected to are shown respectively. The first operational amplifier A1 connected to the output side of the photodiode has a
For photocurrent Ish from photodiode 1 -(I
A voltage output of sh x Rh ) (V) appears and the signal current is changed to a voltage. It is advantageous for the value of Rh to be smaller than the internal resistance Rsh of the photodiode, but in weak light photometry, if Rf is set large for the purpose of increasing the output voltage, the noise voltage of the operational amplifier ^l becomes (1+ Rfx / R
sh) Note that it is magnified twice. In the figure, 3
is an output terminal, 4 is a diode, and Cb and Cfz are dubbing capacitors for rigging and noise reduction.
微弱光測光の誤差には、温度の変化による暗電流の増減
および第1アンプA1の入力インピーダンスに流れる電
流等があるので、バイアス電流の小なるFET入力のオ
ペアンプを用いる。Errors in weak light photometry include increases and decreases in dark current due to temperature changes and current flowing through the input impedance of the first amplifier A1, so an operational amplifier with an FET input having a small bias current is used.
次にフォトダイオード1の接地側に接続された第2のオ
ペアンプA2にて測光出力を絶対値で検波し、利得を合
わせて必要な逆バイアス電圧に変換しそれをフォトダイ
オードに供給する。かがる構成により、微弱光測光の場
合には、バイアス電圧はほとんどOで、第4図に示す方
式に近くなり暗電流対策がなされる。すなわち、VR】
は、高レベル光出力例えば10mWに対し1■、低レベ
ル光出力例えば1mWのときは0.LVというようにセ
ットされているので、暗電流が影響する0、1mWのあ
たりでは、フォトダイオードに加わる電圧は0.01V
ときわめて小になるからである。Next, a second operational amplifier A2 connected to the ground side of the photodiode 1 detects the photometric output in absolute value, adjusts the gain, converts it into a necessary reverse bias voltage, and supplies it to the photodiode. Due to this configuration, in the case of weak light photometry, the bias voltage is almost O, which is similar to the method shown in FIG. 4, and dark current countermeasures are taken. In other words, VR]
is 1■ for a high-level optical output, for example, 10 mW, and 0.0 for a low-level optical output, for example, 1 mW. Since it is set as LV, the voltage applied to the photodiode is 0.01V at around 0.1mW where the dark current is affected.
This is because it becomes extremely small.
大光測の場合には、逆バイアスが深く与えられ、直線限
界点が延び、飽和しな(なり、第3図に示す方式に近く
なる。更に、大光測の場合の光電流Ishが、逆バイア
スによる暗電流より大きく、その誤差は無視できるよう
になる。なお、第2のオペアンプA2の絶対値回路は、
電源投入時および無バイアスの時点でノイズ等が入り、
マイナス側に出力が出ると、順バイアスに反転し大電流
が流れフォトダイオードを破壊することに対する保護と
なる。In the case of large photometry, the reverse bias is deeply applied, the linear limit point is extended, and it is not saturated (it becomes close to the method shown in Fig. 3).Furthermore, the photocurrent Ish in the case of large photometry is It is larger than the dark current due to reverse bias, and its error can be ignored.The absolute value circuit of the second operational amplifier A2 is
Noise etc. may occur when the power is turned on or when there is no bias.
When the output goes to the negative side, the forward bias is reversed and a large current flows to protect the photodiode from being destroyed.
第2図は第1図の回路の出力特性を示し、図において横
軸は順電圧と逆電圧、縦軸は順電流と逆電流、線Cは第
1図の回路の出力特性、矢印を付した線りは光強度の増
加する方向、VOl、 VO2rVO3はフォトダイオ
ードの接地側に印加される電圧を示す。第2図に示され
る特性は、微弱光強度のときは暗電流の少ないVo1=
Δei(V)にあり、光強度が大になるに従ってVo3
までバイアスを印加することを示す。VO3の点は第5
図の直線限界点を避けることになる。Figure 2 shows the output characteristics of the circuit in Figure 1. In the figure, the horizontal axis is forward voltage and reverse voltage, the vertical axis is forward current and reverse current, and line C is the output characteristic of the circuit in Figure 1. The curved line indicates the direction in which the light intensity increases, and VOl, VO2rVO3 indicate the voltage applied to the ground side of the photodiode. The characteristics shown in Figure 2 are that when the light intensity is weak, the dark current is small Vo1=
Δei (V), and as the light intensity increases, Vo3
Indicates that bias is applied up to VO3 score is 5th
This will avoid the straight line limit points in the figure.
以上説明したように本発明によれば、フォトダイオード
を用いた測光方式において、微弱光測定領域での暗電流
の影響の低減、および大光測時の飽和限界領域を拡大す
ることができ、測定精度の向上に有効である。なお、本
発明の適用範囲は上記の例に限定されるものではなく、
各種計測装置へ応用された場合にも及ぶものである。As explained above, according to the present invention, in a photometry method using a photodiode, it is possible to reduce the influence of dark current in the weak light measurement region, and to expand the saturation limit region during high light measurement. Effective for improving accuracy. Note that the scope of application of the present invention is not limited to the above examples,
This also applies to applications to various measuring devices.
第1図は本発明実施例の回路図、−第2図は第1図の回
路の出力特性を示す線図、第3図と第4図は従来例の回
路図、第5図は第3図と第4図の回路の出力特性を示す
線図である。
図中、1はフォトダイオード、2は光、3は出力端子を
それぞれ示す。
第1図
u
第2図
櫃智恵I)Fig. 1 is a circuit diagram of the embodiment of the present invention, - Fig. 2 is a diagram showing the output characteristics of the circuit of Fig. 1, Figs. 3 and 4 are circuit diagrams of the conventional example, and Fig. 5 is a diagram showing the output characteristics of the circuit of Fig. 1. FIG. 5 is a diagram showing the output characteristics of the circuit of FIG. 4 and FIG. In the figure, 1 indicates a photodiode, 2 indicates a light, and 3 indicates an output terminal. Fig. 1 u Fig. 2 Otsuchie I)
Claims (1)
オードの出力側にはフォトダイオードからの光電流を増
幅する第1のオペアンプが接続され、フォトダイオード
の接地側には、測光出力を絶対値で検波し、利得を合わ
せて逆バイアス電圧に変換しフォトダイオードに供給す
る第2のオペアンプが接続されてなることを特徴とする
受光装置。In photometry using a photodiode, a first operational amplifier that amplifies the photocurrent from the photodiode is connected to the output side of the photodiode, and a first operational amplifier that amplifies the photocurrent from the photodiode is connected to the ground side of the photodiode, which detects the photometric output in absolute value and calculates the gain. A light receiving device characterized in that a second operational amplifier is connected which converts the voltage into a reverse bias voltage and supplies it to the photodiode.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP59203105A JPS6181677A (en) | 1984-09-28 | 1984-09-28 | Light receiving apparatus |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP59203105A JPS6181677A (en) | 1984-09-28 | 1984-09-28 | Light receiving apparatus |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS6181677A true JPS6181677A (en) | 1986-04-25 |
Family
ID=16468470
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP59203105A Pending JPS6181677A (en) | 1984-09-28 | 1984-09-28 | Light receiving apparatus |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS6181677A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2019170611A (en) * | 2018-03-28 | 2019-10-10 | セイコーエプソン株式会社 | Light receiving element, light receiving module, photoelectric sensor and biological information measurement device |
JP2019175963A (en) * | 2018-03-28 | 2019-10-10 | セイコーエプソン株式会社 | Light receiving element, light receiving module, photoelectric sensor, and biological information measuring device |
CN111417845A (en) * | 2017-11-24 | 2020-07-14 | 浜松光子学株式会社 | Photodetection circuit |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5621381A (en) * | 1979-07-27 | 1981-02-27 | Mitsubishi Electric Corp | Controlling method of current amplification for avalanche photodiode |
JPS6020654A (en) * | 1983-07-15 | 1985-02-01 | Iwatsu Electric Co Ltd | Optical detecting circuit |
JPS6020655A (en) * | 1983-07-15 | 1985-02-01 | Iwatsu Electric Co Ltd | Optical detecting circuit |
-
1984
- 1984-09-28 JP JP59203105A patent/JPS6181677A/en active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5621381A (en) * | 1979-07-27 | 1981-02-27 | Mitsubishi Electric Corp | Controlling method of current amplification for avalanche photodiode |
JPS6020654A (en) * | 1983-07-15 | 1985-02-01 | Iwatsu Electric Co Ltd | Optical detecting circuit |
JPS6020655A (en) * | 1983-07-15 | 1985-02-01 | Iwatsu Electric Co Ltd | Optical detecting circuit |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111417845A (en) * | 2017-11-24 | 2020-07-14 | 浜松光子学株式会社 | Photodetection circuit |
EP3715803A4 (en) * | 2017-11-24 | 2021-08-04 | Hamamatsu Photonics K.K. | Optical detection circuit |
US11118970B2 (en) | 2017-11-24 | 2021-09-14 | Hamamatsu Photonics K.K. | Optical detection circuit comprising an optical detector to generate voltage between an anode and a cathode due to photoelectromotive force generated in accordance with incident light quantity |
JP2019170611A (en) * | 2018-03-28 | 2019-10-10 | セイコーエプソン株式会社 | Light receiving element, light receiving module, photoelectric sensor and biological information measurement device |
JP2019175963A (en) * | 2018-03-28 | 2019-10-10 | セイコーエプソン株式会社 | Light receiving element, light receiving module, photoelectric sensor, and biological information measuring device |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20070090276A1 (en) | Light detecting device | |
US7129487B2 (en) | Infrared detecting circuit and an infrared detector | |
JPS6181677A (en) | Light receiving apparatus | |
JPH0257740B2 (en) | ||
JP3534443B2 (en) | Optical frequency mixing device | |
JPS6388871A (en) | Optical hybrid integrated circuit device | |
JP2928616B2 (en) | Photodetector | |
US4864120A (en) | Electronic correction of photodiode radiant sensitivity | |
JPS6276329A (en) | Optical reception circuit | |
JPH0690083B2 (en) | Bias automatic variable metering circuit | |
JPS582711A (en) | Sensitivity stabilizing method for photoelectric transducer | |
JP2662036B2 (en) | Appearance inspection equipment for electronic components | |
JPS6365325A (en) | Light quantity detecting circuit | |
JPS62282474A (en) | Semiconductor laser device | |
JPS60259917A (en) | Light-receiving circuit | |
JPS5928718A (en) | Delay circuit | |
JPH0533846B2 (en) | ||
JPS6195219A (en) | Temperature compensation apparatus for photometry circuit | |
JPH0351723Y2 (en) | ||
JPS6219725A (en) | Detecting circuit for semiconductor color sensor | |
JPH09266414A (en) | Logarithmic amplifier for very small current and color identification sensor circuit using it | |
JPH0517493B2 (en) | ||
JPS59127491A (en) | White balance adjustment device of color camera | |
JPH01173440A (en) | Error detecting device in optical disk driving device | |
JPS58205312A (en) | Optical receiving circuit |