JP2005257358A - Gas measuring instrument and gas measuring method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas measuring instrument capable of simply and accurately measuring a plurality of kinds of gases to be measured, and to provide a gas measuring method. <P>SOLUTION: Infrared rays from an infrared light source 1 passed through an atmospheric gas 2 is passed through a wavelength selection means 40 and lights of (N) kinds of wavelengths containing a wavelength hardly absorbed even by any substance in the atmospheric gas 2 are selected to be projected on infrared sensors 11-1N. The infrared sensors 11-1N produce measuring outputs corresponding to detection quantities of light to amplify the same amplifiers 21-2N to output the amplified infrared sensors 11-1N to an operational processing part 33. The operational processing part 33 uses the measuring outputs of the infrared sensors of the wavelength hardly absorbed by any substance not only to nomalize the measuring output of another infrared sensor but also to correct the measuring outputs of the infrared sensors 11-1(N-1) on the basis of the temperature and atmospheric pressure at the time of measurement of infrared rays by a temperature sensor 31 and an atmospheric pressure sensor 32 and the concentration conversion is performed using a reference table stored in a memory part 34 to calculate the concentration of each gas. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

本発明は、赤外線を利用したガス測定装置およびガス測定方法に関する。   The present invention relates to a gas measuring device and a gas measuring method using infrared rays.

従来のガス測定装置として、赤外線の吸収率と被測定対象ガスの濃度とが密接に相関していることを利用して、ガス濃度を測定する赤外線式ガス検知装置があった。このような赤外線式ガス検知装置は被検知ガスを封入するガスセルを備え、赤外線を照射する光源から供給される赤外線を、ガスセルを介して赤外線センサが受光する。そして、赤外線センサの光源側には被検知ガスが吸収する赤外線に対してのみ高い透過率を有するバンドパスフィルタが設けられており、被検知ガスが存在しないときに得られる赤外線センサの検知信号（基準検知信号）を基準として、検知信号の減少割合に基づいて、被検知ガスの濃度を測定する（例えば、特許文献１参照）。
特開２００２−３６５２１７号公報 As a conventional gas measuring device, there has been an infrared type gas detector that measures the gas concentration by utilizing the fact that the infrared absorption rate and the concentration of the gas to be measured are closely correlated. Such an infrared gas detection apparatus includes a gas cell that encloses a gas to be detected, and an infrared sensor receives infrared rays supplied from a light source that emits infrared rays through the gas cell. A band-pass filter having a high transmittance only with respect to the infrared light absorbed by the gas to be detected is provided on the light source side of the infrared sensor, and the detection signal of the infrared sensor obtained when the gas to be detected does not exist ( Using the reference detection signal) as a reference, the concentration of the gas to be detected is measured based on the decrease rate of the detection signal (see, for example, Patent Document 1).
JP 2002-365217 A

しかしながら、上記従来のガス測定装置にあっては、測定対象ガスが一種類の場合の単一ガス測定であるため、複数種類の測定対象ガスがある場合には、測定対象ガス毎にガス測定装置を設けるか、または測定対象ガス毎に赤外光源や赤外線センサを交換して、新たな測定対象ガスを注入し排出する等の処理を行う必要があり、測定に多くの労力と時間を要するという事情があった。また、被測定ガスが存在しない状態に測定された基準検知信号に基づいてガスの測定を行っていたが、実際にガスを測定するときの、赤外光源からの光量の変化等、測定環境の変化によって正確な測定を行うことができない場合があった。   However, in the conventional gas measurement device, since the measurement gas is a single gas measurement when there is one kind of measurement target gas, when there are a plurality of types of measurement target gases, the gas measurement device is provided for each measurement target gas. It is necessary to perform a process such as injecting and discharging a new measurement target gas by replacing the infrared light source or infrared sensor for each measurement target gas, and it takes a lot of labor and time for measurement. There was a situation. In addition, the gas was measured based on the reference detection signal measured in the absence of the gas to be measured, but the measurement environment such as the change in the amount of light from the infrared light source when actually measuring the gas was measured. In some cases, accurate measurement could not be performed due to changes.

本発明は、上記従来の事情に鑑みてなされたものであって、簡単かつ正確に複数種類の測定対象ガスを同時に測定することが可能なガス測定装置およびガス測定方法を提供することを目的とする。   The present invention has been made in view of the above-described conventional circumstances, and an object thereof is to provide a gas measuring device and a gas measuring method capable of simultaneously measuring a plurality of types of measurement target gas easily and accurately. To do.

本発明のガス測定装置は、所定の波長の赤外光を検出する基準赤外線センサを含み、赤外光源からの赤外光を、被測定ガスを介して複数の異なる波長の光をそれぞれ検出する複数の赤外線センサと、
前記複数の赤外線センサのうち、少なくとも、測定対象となるガスの固有赤外線吸収波長の赤外光を受光する赤外線センサの検出信号を、前記基準赤外線センサの検出信号に基づいて正規化する測定対象正規化手段と、
を備える。 The gas measurement apparatus of the present invention includes a reference infrared sensor that detects infrared light of a predetermined wavelength, and detects infrared light from an infrared light source and light of a plurality of different wavelengths through the gas to be measured. Multiple infrared sensors;
Among the plurality of infrared sensors, at least a measurement target normalization that normalizes a detection signal of an infrared sensor that receives infrared light having an intrinsic infrared absorption wavelength of a gas to be measured based on the detection signal of the reference infrared sensor And
Is provided.

この構成により、異なる波長の赤外光をそれぞれ検出する複数の赤外線センサの検出信号を、赤外光源の赤外線強度等の変化に左右されずに測定環境が同じ状態で測定可能な基準赤外線センサの検出信号に基づいて正規化するので、複数種類の測定対象ガスを簡単かつ正確に測定することができる。   With this configuration, the reference infrared sensor that can measure the detection signals of a plurality of infrared sensors that detect infrared light of different wavelengths in the same measurement environment without being influenced by changes in the infrared intensity of the infrared light source, etc. Since normalization is performed based on the detection signal, a plurality of types of measurement target gases can be measured easily and accurately.

また、本発明のガス測定装置において、前記複数の赤外線センサはそれぞれ異なる感度波長を有する。   In the gas measurement device of the present invention, the plurality of infrared sensors have different sensitivity wavelengths.

この構成により、異なる波長にそれぞれ対応した複数の赤外線センサの検出信号を用いて検出するので、複数種類の測定対象ガスを簡単かつ正確に測定することができる。   With this configuration, detection is performed using detection signals from a plurality of infrared sensors respectively corresponding to different wavelengths, so that a plurality of types of measurement target gases can be measured easily and accurately.

また、本発明のガス測定装置は、前記赤外光源からの赤外光から複数の異なる波長を選択する波長選択手段をさらに備え、前記複数の赤外線センサは前記選択された複数の異なる波長の光をそれぞれ検出する。   The gas measuring device of the present invention further includes wavelength selecting means for selecting a plurality of different wavelengths from the infrared light from the infrared light source, and the plurality of infrared sensors are the light of the selected plurality of different wavelengths. Are detected respectively.

この構成により、波長選択手段により、複数の赤外線センサを複数の異なる波長にそれぞれ対応するように波長を選択するので、複数種類の測定対象ガスを簡単かつ正確に測定することができる。   With this configuration, the wavelength selection means selects the wavelengths so that the plurality of infrared sensors correspond to the plurality of different wavelengths, respectively, and therefore it is possible to easily and accurately measure a plurality of types of measurement target gases.

また、本発明のガス測定装置において、前記波長選択手段は前記赤外光源からの赤外光を分光して前記異なる波長の光を出力する分光器を含む。   In the gas measurement device of the present invention, the wavelength selection unit includes a spectroscope that splits infrared light from the infrared light source and outputs light of different wavelengths.

この構成により、波長選択手段を簡単に且つ小型にすることができ、持ち運び可能なガス測定装置を提供することができる。   With this configuration, it is possible to provide a portable gas measuring device in which the wavelength selecting means can be easily and miniaturized.

また、本発明のガス測定装置において、前記波長選択手段は、前記複数の赤外線センサに対応して設けられた複数の赤外線フィルタを含む。   In the gas measurement device of the present invention, the wavelength selection means includes a plurality of infrared filters provided corresponding to the plurality of infrared sensors.

この構成により、波長選択手段を簡単にすることができ、複雑な光学素子が不要なため保守が少なく堅牢なガス測定装置を提供することができる。   With this configuration, it is possible to simplify the wavelength selection means, and to provide a robust gas measuring apparatus with little maintenance because a complicated optical element is unnecessary.

また本発明のガス測定装置は、前記赤外光源の発光波長出力特性、前記波長選択手段の各選択波長毎の波長選択特性、および前記複数の赤外線センサの各センサ毎の受光波長感度特性のうち、少なくとも一つの特性に基づいて、波長毎の発光出力、選択波長透過率および各検出波長毎の受光波長感度が略均一になるように前記赤外線センサからの出力信号を補正する受発光波長特性補正手段をさらに備える。   Further, the gas measuring device of the present invention includes a light emission wavelength output characteristic of the infrared light source, a wavelength selection characteristic for each selected wavelength of the wavelength selection means, and a received wavelength sensitivity characteristic for each sensor of the plurality of infrared sensors. Based on at least one characteristic, light emission / emission wavelength characteristic correction for correcting the output signal from the infrared sensor so that the light emission output for each wavelength, the selected wavelength transmittance, and the light receiving wavelength sensitivity for each detection wavelength are substantially uniform Means are further provided.

この構成により、赤外光源の発光波長出力特性および波長選択手段の各選択波長毎の波長選択特性および複数の赤外線センサの各センサ毎の受光波長感度特性のうちに少なくとも一つの特性に基づいて、波長毎の発光出力および選択波長透過率および各検出波長毎の受光波長感度が見掛け上、均一になるように赤外線センサ信号を補正するので、複数種類の測定対象ガスを簡単かつ正確に測定することができる。   With this configuration, based on at least one of the emission wavelength output characteristics of the infrared light source, the wavelength selection characteristics for each selected wavelength of the wavelength selection means, and the received wavelength sensitivity characteristics for each sensor of the plurality of infrared sensors, Since the infrared sensor signal is corrected so that the emission output and selected wavelength transmittance for each wavelength and the received light wavelength sensitivity for each detection wavelength are apparently uniform, multiple types of measurement target gases can be measured easily and accurately. Can do.

また、本発明のガス測定装置は、前記正規化される前の信号に関して、前記発光波長出力特性、前記波長選択特性および前記受光波長感度特性のうち少なくとも一つと、前記被測定ガスの赤外線センサ検出信号との相関に基づいて作成された受発光波長特性補正テーブルが記憶された受発光波長特性補正テーブル記憶手段をさらに備え、
前記受発光波長特性補正手段は、前記受発光波長特性補正テーブルを参照して前記正規化される前の信号の補正を行う。 Further, the gas measuring device of the present invention is configured to detect at least one of the emission wavelength output characteristic, the wavelength selection characteristic, and the light receiving wavelength sensitivity characteristic with respect to the signal before normalization, and an infrared sensor detection of the gas to be measured. A light receiving / emitting wavelength characteristic correction table storing means in which a light receiving / emitting wavelength characteristic correction table created based on the correlation with the signal is stored;
The light emitting / receiving wavelength characteristic correcting unit performs correction of the signal before normalization with reference to the light receiving / emitting wavelength characteristic correction table.

この構成により、容易に受発光波長特性に対する補正を行うことができる。   With this configuration, the light receiving / emitting wavelength characteristics can be easily corrected.

また、本発明のガス測定装置は、前記測定時の被測定ガスの温度を検出する温度センサ、および前記測定時の被測定ガスの圧力を検出する圧力センサのうち、少なくとも一方を有する測定環境検出手段と、
前記測定環境検出手段の検出結果に基づいて、前記正規化された信号が環境変化に依存しないように環境変化に対して補正する測定環境特性補正手段と、をさらに備える。 Further, the gas measuring device of the present invention is a measurement environment detection having at least one of a temperature sensor for detecting the temperature of the gas under measurement at the time of measurement and a pressure sensor for detecting the pressure of the gas under measurement at the time of measurement. Means,
Measurement environment characteristic correcting means for correcting the environmental change so that the normalized signal does not depend on the environmental change based on the detection result of the measurement environment detecting means.

この構成により、被測定ガスの温度または圧力に起因する測定結果の変化にも追従することが可能となり、より正確な測定結果を得ることができる。   With this configuration, it is possible to follow a change in the measurement result due to the temperature or pressure of the gas to be measured, and a more accurate measurement result can be obtained.

また、本発明のガス測定装置は、前記正規化された信号に関して、前記温度および前記圧力のうち少なくとも一方と前記被測定ガスの濃度との相関に基づいて作成された測定環境特性補正テーブルが記憶された測定環境特性補正テーブル記憶手段をさらに備え、
前記測定環境特性補正手段は、前記測定環境特性補正テーブルを参照して前記正規化された信号の測定環境特性補正を行う。 Further, the gas measuring apparatus of the present invention stores a measurement environment characteristic correction table created based on a correlation between at least one of the temperature and the pressure and the concentration of the gas to be measured with respect to the normalized signal. The measurement environment characteristic correction table storage means is further provided,
The measurement environment characteristic correction unit performs measurement environment characteristic correction of the normalized signal with reference to the measurement environment characteristic correction table.

この構成により、容易に温度または圧力に対する補正を行うことができる。   With this configuration, correction for temperature or pressure can be easily performed.

また、本発明のガス測定装置は、前記正規化および前記補正がなされた信号を、前記測定対象ガス毎に濃度信号に変換する濃度変換手段をさらに備える。   In addition, the gas measurement device of the present invention further includes concentration conversion means for converting the normalized and corrected signal into a concentration signal for each measurement target gas.

この構成により、測定対象ガスの測定結果として、その濃度情報を得ることができる。   With this configuration, the concentration information can be obtained as the measurement result of the measurement target gas.

また、本発明のガス測定装置では、前記濃度変換手段は前記濃度変換テーブルを参照して前記濃度変換を行う。   In the gas measuring device of the present invention, the concentration conversion means performs the concentration conversion with reference to the concentration conversion table.

この構成により、容易に濃度変換を行うことができる。   With this configuration, the density conversion can be easily performed.

また、前記所定の波長は、被測定ガス中の赤外線透過率が所定値以上となる波長である。   The predetermined wavelength is a wavelength at which the infrared transmittance in the gas to be measured is a predetermined value or more.

この構成により、基準赤外線センサとして赤外線透過率が高い波長に対応したものを選択すれば、基準赤外線センサの出力は大気中に含まれるガスに起因して変化することが少ないので、安定して正確な測定結果を得ることができる。   With this configuration, if a reference infrared sensor corresponding to a wavelength with high infrared transmittance is selected, the output of the reference infrared sensor is less likely to change due to gas contained in the atmosphere. Measurement results can be obtained.

また、前記複数の赤外線センサが、１次元または２次元のアレイ状に配置されてケースに格納された赤外線センサユニットを有する。   The plurality of infrared sensors have an infrared sensor unit arranged in a one-dimensional or two-dimensional array and stored in a case.

この構成により、前記複数の赤外線センサを整列して配置し、赤外ユニットとして筐体に収納するので、ガス測定装置を小型化することができる。   With this configuration, the plurality of infrared sensors are aligned and housed in the housing as an infrared unit, so that the gas measuring device can be reduced in size.

また、前記複数の赤外線センサは、焦電型赤外線センサである。   The plurality of infrared sensors are pyroelectric infrared sensors.

この構成により、赤外線センサが焦電型赤外線センサであるため、モジュール化等の小型化が可能となり、可搬型のガス測定器を実現することができる。   With this configuration, since the infrared sensor is a pyroelectric infrared sensor, downsizing such as modularization is possible, and a portable gas measuring instrument can be realized.

本発明のガス測定方法は、被測定ガスを通過させた赤外光源からの赤外光より所定の波長の光と、測定対象となるガスの固有赤外線吸収波長の赤外光を検出するステップと、
前記測定対象となるガスの固有赤外線吸収波長に対応した赤外線センサの検出信号を、前記基準赤外線センサの検出信号に基づいて正規化するステップと、
を備える。 The gas measurement method of the present invention includes a step of detecting light having a predetermined wavelength from infrared light from an infrared light source that has passed a gas to be measured, and infrared light having an intrinsic infrared absorption wavelength of the gas to be measured. ,
Normalizing the detection signal of the infrared sensor corresponding to the intrinsic infrared absorption wavelength of the gas to be measured based on the detection signal of the reference infrared sensor;
Is provided.

この方法により、異なる波長の赤外光をそれぞれ検出する複数の赤外線センサの検出信号を、赤外光源の赤外線強度等の変化に左右されずに測定環境が同じ状態で測定可能な基準赤外線センサの検出信号に基づいて正規化するので、複数種類の測定対象ガスを簡単かつ正確に測定することができる。   By this method, the detection signal of a plurality of infrared sensors that respectively detect infrared light of different wavelengths can be measured by a reference infrared sensor that can be measured in the same measurement environment without being affected by changes in the infrared intensity of the infrared light source. Since normalization is performed based on the detection signal, a plurality of types of measurement target gases can be measured easily and accurately.

本発明によれば、簡単かつ正確に複数種類の測定対象ガスを測定することが可能なガス測定装置およびガス測定方法を提供することができる。   ADVANTAGE OF THE INVENTION According to this invention, the gas measuring device and gas measuring method which can measure several types of measuring object gas easily and correctly can be provided.

以下、本発明のガス測定装置およびガス測定方法の実施形態として、大気ガス測定装置および大気ガス測定方法について、図面を用いて説明する。なお、本実施形態では、被測定ガスを大気ガスとし、測定対象ガスとして温室効果ガスや排気ガス等を測定する大気ガス測定装置および大気ガス測定方法を例にとって説明する。   Hereinafter, as an embodiment of a gas measuring device and a gas measuring method of the present invention, an atmospheric gas measuring device and an atmospheric gas measuring method will be described with reference to the drawings. In the present embodiment, an explanation will be given by taking as an example an atmospheric gas measuring apparatus and an atmospheric gas measuring method for measuring a greenhouse gas, an exhaust gas, or the like as a measurement target gas.

（第１の実施形態）
図１は、本発明の第１の実施形態の大気ガス測定装置の概略構成を示す図である。図１に示すように、大気ガス測定装置１０は、赤外光源１からの赤外線を、大気ガス２を介して測定するものである。赤外光源１としては、太陽光のほか、８００ｎｍから１２μｍ程度の広帯域の波長成分を持ち、各波長における出力がほぼ一定である赤外線等を発生する光源でもよく、また測定に必要な波長成分を持つ単独赤外発光源を寄せ集めたものでも良い。 (First embodiment)
FIG. 1 is a diagram showing a schematic configuration of an atmospheric gas measurement device according to a first embodiment of the present invention. As shown in FIG. 1, the atmospheric gas measuring device 10 measures infrared rays from an infrared light source 1 via an atmospheric gas 2. In addition to sunlight, the infrared light source 1 may be a light source that emits infrared light having a broad wavelength component of about 800 nm to 12 μm and a substantially constant output at each wavelength. It may be a collection of single infrared emission sources.

まず、本実施形態の大気ガス測定装置および測定方法の原理について説明する。前述したようにガスの種類によって、そのガス毎に固有の波長の赤外線を吸収する特質をもっている。例えば、大気ガス２中に含まれる炭酸ガスやメタンガス等の地球温暖化の原因になっている温室効果ガスや、ＮＯｘ、ＳＯｘ、ＣＯｘ等の排気ガス等では、例えば、メタンガスは約３．３１１μｍ、二酸化炭素は約４．３５μｍ、一酸化炭素は約４．６５μｍ、一酸化窒素は約５．２６μｍ、二酸化窒素は約６．２１μｍ等の波長の赤外線を吸収する特質を持っている。また、赤外光の吸収率は各被測定対象ガスの濃度に対して指数関数的に比例する関係にある。   First, the principle of the atmospheric gas measurement device and measurement method of this embodiment will be described. As described above, depending on the type of gas, each gas has a characteristic of absorbing infrared light having a specific wavelength. For example, in the greenhouse gas that causes global warming such as carbon dioxide gas and methane gas contained in the atmospheric gas 2 and exhaust gas such as NOx, SOx, COx, etc., for example, methane gas is about 3.311 μm, Carbon dioxide has a characteristic of absorbing infrared rays having a wavelength of about 4.35 μm, carbon monoxide is about 4.65 μm, nitrogen monoxide is about 5.26 μm, and nitrogen dioxide is about 6.21 μm. Further, the absorption rate of infrared light has a relationship that is exponentially proportional to the concentration of each gas to be measured.

このため、測定対象ガスを通過させた対象ガス固有の吸収波長の赤外光を赤外線センサで検出し測定した時の出力は、測定対象ガスの濃度の増加に対し指数関数的に減少する。各固有波長の赤外線を吸収する特質を持つ、つまり、ある固有波長の赤外線を吸収する測定対象ガスの濃度が高くなると、その測定対象ガスによりその固有波長の赤外線も多く吸収されるようになるので、その固有波長の赤外線を測定する赤外線センサの測定出力は低下する。一方、その測定対象ガスの濃度が低くなれば、その固有波長の赤外線を測定している赤外線センサの測定出力は高くなる関係にある。   For this reason, the output when the infrared light having the absorption wavelength unique to the target gas that has passed through the measurement target gas is detected and measured by the infrared sensor decreases exponentially with the increase in the concentration of the measurement target gas. Because it has the property of absorbing infrared of each specific wavelength, that is, when the concentration of the measurement target gas that absorbs infrared of a specific wavelength increases, the measurement target gas also absorbs a large amount of infrared of that specific wavelength. The measurement output of the infrared sensor that measures the infrared light of the specific wavelength decreases. On the other hand, if the concentration of the measurement target gas is low, the measurement output of the infrared sensor that measures the infrared light of the specific wavelength is high.

本実施形態の大気ガス測定装置１０は、大気ガス２を通過した赤外光源１からの赤外光を受光する複数個の赤外線センサ１１〜１Ｎが、その受光量に応じた測定出力を発生し、測定時の測定環境に基づき調整処理をしてガスの濃度を求めるものである。   In the atmospheric gas measurement device 10 of the present embodiment, a plurality of infrared sensors 11 to 1N that receive infrared light from the infrared light source 1 that has passed through the atmospheric gas 2 generate measurement outputs according to the amount of light received. The gas concentration is obtained by performing an adjustment process based on the measurement environment at the time of measurement.

次に、この第１の実施形態の大気ガス測定装置１０の内部構成について説明する。本実施形態の大気ガス測定装置１０は、図１に示すように、異なるＮ（Ｎは２以上の任意の整数）個の波長の光を選択する波長選択手段４０と、波長選択手段４０により選択されたＮ個の波長に対応して設けられるＮ個の赤外線センサ１１〜１Ｎと、各赤外線センサ１１〜１Ｎからの測定出力を夫々増幅する増幅器２１〜２Ｎと、各赤外線センサ１１〜１Ｎの測定時の温度を測定する温度センサ３１と、その測定時の気圧を測定する気圧センサ３２と、演算処理部３３と、演算処理部３３に内蔵または隣接して設けられ、補正テーブルや濃度変換テーブル等の参照テーブル等が記憶されたＲＡＭやＲＯＭ等の記憶部３４とを有している。   Next, the internal configuration of the atmospheric gas measurement device 10 of the first embodiment will be described. As shown in FIG. 1, the atmospheric gas measurement device 10 of the present embodiment is selected by wavelength selection means 40 for selecting light of different N wavelengths (N is an arbitrary integer equal to or greater than 2), and wavelength selection means 40. N infrared sensors 11 to 1N provided corresponding to the N wavelengths thus formed, amplifiers 21 to 2N for amplifying measurement outputs from the infrared sensors 11 to 1N, respectively, and measurements of the infrared sensors 11 to 1N A temperature sensor 31 that measures the temperature of the hour, an atmospheric pressure sensor 32 that measures the atmospheric pressure at the time of measurement, an arithmetic processing unit 33, and a built-in or adjacent to the arithmetic processing unit 33, a correction table, a density conversion table, etc. And a storage unit 34 such as a RAM or a ROM in which a reference table is stored.

波長選択手段４０は、Ｎ個の波長フィルター４１〜４Ｎを有し、赤外光源１からの赤外光を、異なるＮ個の波長の光を出力する。   The wavelength selection unit 40 includes N wavelength filters 41 to 4N, and outputs infrared light from the infrared light source 1 as light having different N wavelengths.

赤外線センサ１１〜１Ｎは、波長選択手段４０の波長フィルター４１〜４Ｎの近傍にそれぞれ設けられる。また、Ｎ個の赤外線センサ１１〜１Ｎのうち少なくとも１個以上の赤外線センサは基準となる検出信号を出力する赤外線センサであり、それに対応した波長選択手段４０の波長フィルターは被測定ガスの吸収波長以外の所定の波長選択特性を有する。本実施形態においては、この基準となる検出信号を出力する赤外線センサが、赤外線センサ１Ｎの１個の場合を例にとって説明する。   The infrared sensors 11 to 1N are provided in the vicinity of the wavelength filters 41 to 4N of the wavelength selection unit 40, respectively. In addition, at least one of the N infrared sensors 11 to 1N is an infrared sensor that outputs a reference detection signal, and the wavelength filter of the wavelength selection unit 40 corresponding thereto has an absorption wavelength of the gas to be measured. It has a predetermined wavelength selection characteristic other than. In the present embodiment, an example will be described in which the infrared sensor 1N that outputs the reference detection signal is one infrared sensor 1N.

この所定の波長は、大気ガス２中に含まれるどのガスにも吸収されにくい波長が好ましい。この場合、大気ガスを測定する際に、大気ガス２中に含まれるガスによる影響がないため、安定して正確な測定を行うことが可能となる。   The predetermined wavelength is preferably a wavelength that is not easily absorbed by any gas contained in the atmospheric gas 2. In this case, when measuring the atmospheric gas, there is no influence of the gas contained in the atmospheric gas 2, so that stable and accurate measurement can be performed.

ここで、大気ガス２中に含まれるどのガスにも吸収されにくい波長としては、大気中の赤外線透過率が所定値、例えば７０％以上となる波長帯域である。具体的には、気温２５度、１気圧の条件で、赤外線透過率が７０％以上となる波長は、約１．５μｍ以上約１．７μｍ以下、約２．１μｍ以上約２．３μｍ以下、３．８μｍ以上約４．０μｍ以下、約８．４μｍ以上約９．３μｍ以下、約９．９μｍ以上約１２．７μｍ以下、等である。したがって、波長フィルター４Ｎの選択波長は、これらの波長に含まれていることが好ましい。また、各々の波長フィルター４１〜４Ｎの選択波長には帯域幅を有するがこの帯域幅はできるだけ不要な波長を含まないほうが好ましくその値は、０．１μｍ程度が好ましい。   Here, the wavelength that is hardly absorbed by any gas contained in the atmospheric gas 2 is a wavelength band in which the infrared transmittance in the atmosphere is a predetermined value, for example, 70% or more. Specifically, the wavelength at which the infrared transmittance is 70% or more under conditions of an air temperature of 25 degrees and 1 atmosphere is about 1.5 μm to about 1.7 μm, about 2.1 μm to about 2.3 μm, 3 0.8 μm or more and about 4.0 μm or less, about 8.4 μm or more and about 9.3 μm or less, about 9.9 μm or more and about 12.7 μm or less. Therefore, it is preferable that the selection wavelength of the wavelength filter 4N is included in these wavelengths. Further, although the wavelength selected for each of the wavelength filters 41 to 4N has a bandwidth, it is preferable that this bandwidth does not include unnecessary wavelengths as much as possible, and the value is preferably about 0.1 μm.

演算処理部３３はＡ／Ｄ変換およびＤ／Ａ変換機能を有し、赤外光測定時の測定環境に基づいたリアルタイムの正規化処理や、赤外光源１の発光波長出力特性と波長選択手段４０の波長選択特性と各赤外線センサ１１〜１Ｎの受光波長感度特性とのうち少なくとも一つの特性に基づく受発光波長特性補正処理や、温度や気圧に基づく測定環境特性補正処理等の調整処理や、濃度変換処理を行って、複数種類の被測定対象ガスの濃度を求める。   The arithmetic processing unit 33 has A / D conversion and D / A conversion functions, real-time normalization processing based on the measurement environment during infrared light measurement, emission wavelength output characteristics and wavelength selection means of the infrared light source 1 Adjustment processing such as light receiving / emitting wavelength characteristic correction processing based on at least one of the wavelength selection characteristics of 40 and the light receiving wavelength sensitivity characteristics of the infrared sensors 11 to 1N, measurement environment characteristic correction processing based on temperature and atmospheric pressure, Concentration conversion processing is performed to determine the concentrations of a plurality of types of measurement target gases.

記憶部３４には、接続されている各赤外線センサ１１〜１Ｎと、波長選択手段４０で選択された受光波長とが対応付けられて記憶されている。   In the storage unit 34, each of the connected infrared sensors 11 to 1N and the light receiving wavelength selected by the wavelength selection unit 40 are stored in association with each other.

次に、本実施形態の大気ガス測定装置１０の動作を説明する。   Next, operation | movement of the atmospheric gas measuring apparatus 10 of this embodiment is demonstrated.

大気ガス２を通過した赤外光源１からの赤外光は、波長選択手段４０を通過する。波長選択手段４０は、大気ガス２中に含まれる複数種類の測定対象ガス夫々の固有吸収波長の光及び大気ガス２中に含まれるどの物質にも吸収されにくい波長の光とをＮ種類選択する。夫々の選択された波長の光は、その選択された波長と１対１で対応する複数個の赤外線センサ１１〜１Ｎに夫々投射される。   The infrared light from the infrared light source 1 that has passed through the atmospheric gas 2 passes through the wavelength selection means 40. The wavelength selection unit 40 selects N types of light having a specific absorption wavelength of each of a plurality of types of measurement target gases contained in the atmospheric gas 2 and light having a wavelength that is difficult to be absorbed by any substance contained in the atmospheric gas 2. . Each selected wavelength of light is projected onto a plurality of infrared sensors 11 to 1N corresponding one-to-one with the selected wavelength.

赤外線センサ１１〜１Ｎは、投射された夫々の波長の光の入射赤外光量を測定し、測定した値を電気信号に変換して増幅器２１〜２Ｎへ出力する。そして、増幅器２１〜２Ｎによって、各赤外線センサ１１〜１Ｎからの測定出力が所定の倍率で信号増幅して演算処理部３３へ出力される。また、温度センサ３１および気圧センサ３２は、それぞれ、赤外光量測定時の大気中の温度および気圧を検出して演算処理部３３へ出力する。   The infrared sensors 11 to 1N measure the incident infrared light amounts of the projected light beams having the respective wavelengths, convert the measured values into electric signals, and output the electric signals to the amplifiers 21 to 2N. Then, the amplifiers 21 to 2N amplify the measurement outputs from the infrared sensors 11 to 1N at a predetermined magnification and output the amplified signals to the arithmetic processing unit 33. Further, the temperature sensor 31 and the atmospheric pressure sensor 32 detect the temperature and atmospheric pressure in the atmosphere at the time of measuring the amount of infrared light, and output them to the arithmetic processing unit 33.

演算処理部３３は、先ず、増幅器２１〜２ＮのＮ個の出力信号をＡ／Ｄ変換する。そして、測定のハードウェアである赤外光源１、波長フィルター４１〜４Ｎ、および赤外線センサ１１〜１Ｎについて、各波長毎の個々の特性のばらつきによる誤差を最小限にするため受発光波長特性補正等の調整処理を行う。   The arithmetic processing unit 33 first A / D-converts N output signals from the amplifiers 21 to 2N. And, for the infrared light source 1, wavelength filters 41 to 4N, and infrared sensors 11 to 1N, which are measurement hardware, correction of light receiving and emitting wavelength characteristics, etc. in order to minimize errors due to variations in individual characteristics for each wavelength. Perform the adjustment process.

この受発光波長特性補正は、たとえば、演算処理部３３が記憶部３４を利用することで行われる。記憶部３４には、予め、赤外光源１の波長別発光強度を示す発光波長出力特性、波長選択手段４０の各波長別透過率を示す波長選択特性、および各赤外線センサ１１〜１Ｎの波長別受光感度を示す受光波長感度特性における夫々のＮ個の波長別特性と、被測定ガスの赤外線センサ検出信号との相関に基づいて作成されたに受発光波長特性テーブルが記憶されている。そして、演算処理部３３は、この受発光波長特性テーブルに基づいて、これらの波長別特性、すなわち各ハードウェア毎に関して波長特性が見掛け上すべて均一になるようにＡ／Ｄ変換されたＮ個の出力に対してリアルタイムでＮ個の出力を補正する受発光波長特性補正等の調整処理を行う。なお、この受発光波長特性補正は、発光波長出力特性、波長選択特性、受光波長感度特性のうち少なくとも一つに基づいて行われればよい。   This light receiving / emitting wavelength characteristic correction is performed by the arithmetic processing unit 33 using the storage unit 34, for example. In the storage unit 34, the emission wavelength output characteristic indicating the emission intensity for each wavelength of the infrared light source 1, the wavelength selection characteristic indicating the transmittance for each wavelength of the wavelength selection means 40, and the wavelength for each infrared sensor 11 to 1N. A light reception / emission wavelength characteristic table created based on the correlation between each N wavelength characteristic in the light reception wavelength sensitivity characteristic indicating the light reception sensitivity and the infrared sensor detection signal of the gas to be measured is stored. Then, the arithmetic processing unit 33 performs A / D conversion of N pieces of the characteristics for each wavelength, that is, the wavelength characteristics for each hardware seemingly uniform based on the light receiving / emitting wavelength characteristic table. Adjustment processing such as light receiving and emitting wavelength characteristic correction for correcting N outputs in real time with respect to the output is performed. The light receiving / emitting wavelength characteristic correction may be performed based on at least one of the light emitting wavelength output characteristic, the wavelength selection characteristic, and the light receiving wavelength sensitivity characteristic.

次に、赤外光源１の発光強度の変化や、大気ガス２中を通過する際の赤外線の透過強度の変化に対しても測定精度を向上させることができるように、測定環境変化に基づく補正処理の一つとして、固有ガスのセンシング信号である各赤外線センサ１１〜１（Ｎ−１）からの増幅および受発光波長特性補正がなされた後の値を、大気ガス２中に含まれるどの物質にも吸収されにくい波長の光を測定する赤外線センサ１Ｎからの信号を増幅した増幅器２Ｎの出力信号の特性補正後の値で除する等の処理を行って正規化処理をする。   Next, correction based on changes in the measurement environment so that the measurement accuracy can be improved with respect to changes in the emission intensity of the infrared light source 1 and changes in the infrared transmission intensity when passing through the atmospheric gas 2. As one of the processes, the value after the amplification from each of the infrared sensors 11 to 1 (N-1) and the correction of the light receiving and emitting wavelength characteristics, which is a sensing signal of the intrinsic gas, is used as any substance contained in the atmospheric gas 2 In addition, normalization is performed by performing processing such as dividing the signal from the infrared sensor 1N that measures light having a wavelength that is difficult to be absorbed by the amplified value of the output signal of the amplifier 2N.

さらに、ガスの濃度は温度および気圧に対し変化が大きいため、演算処理部３３では、測定環境変化に基づく補正処理の一つとして、温度センサ３１と気圧センサ３２のうち少なくとも一方の検出出力に基づいて、正規化した赤外線センサ１１〜１（Ｎ−１）の出力信号の値を、基準温度または基準気圧のときの値になるようにリアルタイムで測定環境特性補正等の調整処理を行う。   Further, since the gas concentration greatly changes with respect to the temperature and the atmospheric pressure, the arithmetic processing unit 33 is based on the detection output of at least one of the temperature sensor 31 and the atmospheric pressure sensor 32 as one of the correction processes based on the measurement environment change. Then, adjustment processing such as measurement environment characteristic correction is performed in real time so that the values of the normalized output signals of the infrared sensors 11 to 1 (N-1) become values at the reference temperature or the reference atmospheric pressure.

温度圧力等の測定環境変化に対する補正については、温度および圧力のうち少なくとも一方の値と、各ガスの濃度との関係を予め測定して、正規化された赤外線センサ１１〜１（Ｎ−１）を補正するための測定環境特性補正テーブルを作成して記憶部３４に記憶しておき、正規化した赤外線センサ１１〜１（Ｎ−１）の出力信号と、温度センサ３１および気圧センサ３２の少なくとも一方とからの検出出力を入力にして、測定環境特性補正テーブルの値を参照して、測定環境特性補正を行う。これにより、簡単に補正処理を行うことができる。   For correction of measurement environment changes such as temperature and pressure, the relationship between at least one of temperature and pressure and the concentration of each gas is measured in advance, and normalized infrared sensors 11 to 1 (N-1). Is created and stored in the storage unit 34, and normalized output signals of the infrared sensors 11 to 1 (N-1), at least the temperature sensor 31 and the atmospheric pressure sensor 32 are stored. The detection output from one is input, and the measurement environment characteristic correction is performed with reference to the value of the measurement environment characteristic correction table. Thereby, the correction process can be easily performed.

なお、温度や気圧が、大気ガス２中に含まれるどの物質にも吸収されにくい感度波長をもつ赤外線センサ１Ｎからの出力信号にも影響を与える場合には、前記正規化処理の前に赤外線センサ１Ｎからの出力信号の値も補正するか、正規化した赤外線センサ１１〜１（Ｎ−１）の出力信号の値にその影響がなくなるような補正を行うようにする。   If the temperature or atmospheric pressure also affects the output signal from the infrared sensor 1N having a sensitivity wavelength that is difficult to be absorbed by any substance contained in the atmospheric gas 2, the infrared sensor is used before the normalization process. The value of the output signal from 1N is also corrected, or correction is made so as not to affect the value of the output signal of the normalized infrared sensors 11-1 (N-1).

ここで、被測定対象ガス毎にガス濃度に対する赤外線吸収量が異なる。また、上記の正規化および補正を行った信号のレベルは、固有のガス濃度が高いときには低く、固有のガス濃度が低いときには高くなる。そこで、演算処理部３３が各ガス毎に正規化および補正された信号を、要求された任意の精度の濃度信号に変換することで、より正確な濃度信号を出力することができる。   Here, the amount of infrared absorption relative to the gas concentration differs for each gas to be measured. Further, the level of the signal subjected to the normalization and correction described above is low when the specific gas concentration is high, and is high when the specific gas concentration is low. Therefore, the arithmetic processing unit 33 converts the signal normalized and corrected for each gas into a concentration signal having any required accuracy, so that a more accurate concentration signal can be output.

これは、演算処理部３３では、各ガス毎に濃度と赤外線センサ１１〜１（Ｎ−１）の測定出力との関係を予め測定して、各ガス毎に、濃度と、正規化および補正された赤外線センサ１１〜１（Ｎ−１）の出力との関係を対応付けた濃度変換テーブルを作成して、記憶部３４に記憶しておく。そして、濃度変換を行うときには、その濃度変換テーブルを参照して各測定対象ガス毎に濃度変換を行う。これにより、簡単に濃度変換処理を行うことができる。   This is because the arithmetic processing unit 33 measures in advance the relationship between the concentration and the measurement output of the infrared sensors 11 to 1 (N-1) for each gas, and normalizes and corrects the concentration for each gas. A density conversion table that associates the relationship with the outputs of the infrared sensors 11 to 1 (N−1) is created and stored in the storage unit 34. When concentration conversion is performed, concentration conversion is performed for each measurement target gas with reference to the concentration conversion table. Thereby, the density conversion process can be easily performed.

演算処理部３３は、以上説明したような正規化や補正等の調整処理、および濃度変換処理を赤外線センサ１１〜１（Ｎ−１）の各測定出力に対して行ない、必要に応じて、各赤外線センサ１１〜１（Ｎ−１）による各測定対象ガスの測定濃度としてディジタル値で出力したり、また必要あればＤ／Ａ変換をしてアナログ値で出力したり、また必要に応じて数字表示等の出力を行う。   The arithmetic processing unit 33 performs the adjustment processing such as normalization and correction as described above, and the density conversion processing for each measurement output of the infrared sensors 11 to 1 (N−1), and if necessary, Output as a digital value as the measured concentration of each measurement target gas by the infrared sensors 11 to 1 (N-1), or output as an analog value after D / A conversion if necessary, or as necessary. Performs display and other output.

このような本発明の第１の実施形態の大気ガス測定装置および大気ガス測定方法によれば、被測定対象物である大気中のガス２を介し赤外光源１からの赤外光を、大気中のガスにより吸収されにくい波長を含めた複数個の吸収波長を選択する波長選択手段４０と、選択した波長に夫々対応した複数個の赤外線センサ１１〜１Ｎを設け、それら複数個の赤外線センサ１１〜１Ｎにより受光し、吸収されにくい波長の赤外線センサＮの測定出力を用いて、他の赤外線センサ１１〜１（Ｎ−１）の測定出力を正規化すると共に、参照テーブルを用いて発光波長出力特性、波長選択特性、受光波長感度特性により受発光赤外光測定条件を均一にするために測定出力を受発光波長特性補正し、さらに測定時の温度と気圧を計測してその値により測定出力を測定環境特性補正し、濃度換算を行うことにより、大気ガス２中に含まれる複数種類の被測定対象ガスの濃度を測定する場合でも、赤外光源１および波長選択手段４０および赤外線センサ１１〜１Ｎの夫々について個々の特性の違いや、測定環境の変化や赤外光源１の出力変化や、温度や気圧等の測定環境の変化に依存せず、簡単かつ正確に一度に測定することができる。   According to the atmospheric gas measuring apparatus and the atmospheric gas measuring method of the first embodiment of the present invention, the infrared light from the infrared light source 1 is converted into the atmosphere via the atmospheric gas 2 that is the object to be measured. There are provided wavelength selection means 40 for selecting a plurality of absorption wavelengths including wavelengths that are difficult to be absorbed by the gas therein, and a plurality of infrared sensors 11 to 1N respectively corresponding to the selected wavelengths. The measurement output of the other infrared sensors 11 to 1 (N−1) is normalized using the measurement output of the infrared sensor N having a wavelength that is received by ˜1N and is not easily absorbed, and the emission wavelength output using the reference table The measurement output is corrected for receiving and emitting wavelength characteristics in order to make the measurement conditions for receiving and emitting infrared light uniform by the characteristics, wavelength selection characteristics, and received light wavelength sensitivity characteristics, and the measurement output is measured based on the measured temperature and atmospheric pressure. Even when measuring the concentration of a plurality of types of gas to be measured contained in the atmospheric gas 2 by correcting the measurement environment characteristics and converting the concentration, the infrared light source 1, the wavelength selection means 40, and the infrared sensors 11 to 1N are measured. It is possible to measure easily and accurately at a time without depending on the difference in individual characteristics, changes in the measurement environment, changes in the output of the infrared light source 1, and changes in the measurement environment such as temperature and pressure.

なお、上記第１の実施形態の説明では、説明の便宜上、大気ガス２中に含まれるどの物質にも吸収されにくい波長として１波長について説明したが、本発明では、これに限らず、２波長でも、３波長でも、少なくとも１波長以上であれば良い。このような大気ガス２中に含まれるどの物質にも吸収されにくい波長に対応した赤外線センサの測定出力は、上述したように、大気ガス２中に含まれる被測定対象ガスの濃度を測定する複数個の赤外線センサの測定出力を正規化するために使用するものであるので、このような正規処理のための赤外線センサを多く設けるほど、赤外光源１の発光強度の変化や、大気ガス２中を通過する際の赤外線の透過強度の変化をより正確に検出することが可能となり、各被測定対象ガスの濃度の測定精度をより向上させることが可能になる。   In the description of the first embodiment, for convenience of explanation, one wavelength has been described as a wavelength that is difficult to be absorbed by any substance contained in the atmospheric gas 2. However, the present invention is not limited to this. However, even three wavelengths may be at least one wavelength. As described above, the measurement output of the infrared sensor corresponding to the wavelength that is difficult to be absorbed by any substance contained in the atmospheric gas 2 is a plurality of measurement outputs for measuring the concentration of the measurement target gas contained in the atmospheric gas 2. Since it is used to normalize the measurement outputs of the individual infrared sensors, the more infrared sensors for such regular processing are provided, the more the emission intensity of the infrared light source 1 changes and the atmospheric gas 2 It becomes possible to more accurately detect the change in infrared transmission intensity when passing through the gas, and to improve the measurement accuracy of the concentration of each measurement target gas.

また、演算処理部は、全ての赤外線センサ入力を演算処理する必要はなく、複数個の基準センサ出力を平均、分散等の演算処理をして使用することにより正規化する選択された測定対象ガスの固有吸収波長を含むような波長に対応する赤外線センサからの入力のみを演算処理してもよい。また、予め測定対象ガスを決定している場合は、その測定対象ガスの固有吸収波長の波長選択手段とその波長に対応した赤外線センサのみを配置してもよい。   In addition, the arithmetic processing unit does not need to perform arithmetic processing on all infrared sensor inputs, and the selected measurement target gas that is normalized by using a plurality of reference sensor outputs by performing arithmetic processing such as averaging and dispersion. Only the input from the infrared sensor corresponding to the wavelength including the intrinsic absorption wavelength may be processed. Further, when the measurement target gas is determined in advance, only the wavelength selection means for the intrinsic absorption wavelength of the measurement target gas and the infrared sensor corresponding to the wavelength may be arranged.

また、上記第１の実施形態の説明では、赤外光源１の波長別発光強度を示す発光波長出力特性、波長フィルター４１〜４Ｎを包含する波長選択手段４０の各波長別透過率を示す波長選択特性、各赤外線センサ１１〜１Ｎの波長別受光感度を示す受光波長感度特性、の波長別特性の受発光波長特性補正を正規化処理の前に行う場合について説明したが、正規化処理の後に行ってもよい。この場合は、発光波長出力特性、波長選択特性、受光波長感度特性、のそれぞれについて、被測定ガスの波長における特性が基準となる検出信号を出力する赤外線センサ１Ｎの受光波長である所定の波長における特性と同じになるように、正規化処理後の(Ｎ−１)個の信号に対し、受発光波長特性補正処理をする。   Further, in the description of the first embodiment, the wavelength selection indicating the emission wavelength output characteristic indicating the emission intensity for each wavelength of the infrared light source 1 and the transmittance for each wavelength of the wavelength selection means 40 including the wavelength filters 41 to 4N. In the above description, the light receiving / emitting wavelength characteristic correction of the wavelength-specific characteristics of the infrared light sensors 11 to 1N indicating the light-receiving wavelength sensitivity characteristics of the infrared sensors 11 to 1N has been described before the normalization process. May be. In this case, for each of the emission wavelength output characteristics, wavelength selection characteristics, and light reception wavelength sensitivity characteristics, at a predetermined wavelength that is the light reception wavelength of the infrared sensor 1N that outputs a detection signal based on the characteristics at the wavelength of the gas to be measured. The light receiving / emitting wavelength characteristic correction processing is performed on the (N−1) signals after the normalization processing so as to be the same as the characteristics.

また、上記第１の実施形態の説明では、演算処理部３３における測定環境に基づく調整処理の一例として、大気ガス２中に含まれるどの物質にも吸収されにくい感度波長を波長選択手段により選択しその波長に対応した赤外線センサによって被測定対象ガスの濃度を測定する複数個の赤外線センサの測定出力を正規化することや、参照テーブルを用いて赤外光源１の波長別発光強度や波長フィルター４１〜４Ｎを包含する波長選択手段４０の各波長別透過率や各赤外線センサ１１〜１Ｎの波長別受光感度に対するばらつきの補正処理、および温度と気圧とによる補正処理等を全て行うように説明したが、本発明では、これらに限らず、測定環境によっては、正規化処理や、波長別特性の補正処理や、温度や気圧に基づく補正処理等の処理に不要な処理があれば、省略しても勿論よい。   In the description of the first embodiment, as an example of the adjustment process based on the measurement environment in the arithmetic processing unit 33, the wavelength selection unit selects a sensitivity wavelength that is difficult to be absorbed by any substance contained in the atmospheric gas 2. Normalizing the measurement output of a plurality of infrared sensors that measure the concentration of the gas to be measured by the infrared sensor corresponding to the wavelength, or using the reference table, the emission intensity for each wavelength of the infrared light source 1 and the wavelength filter 41 In the above description, the wavelength selection means 40 including ˜4N and the wavelength-dependent transmittance and the infrared sensors 11 to 1N are subjected to the correction processing for variation with respect to the wavelength-dependent light reception sensitivity and the correction processing based on temperature and atmospheric pressure. In the present invention, depending on the measurement environment, the present invention is not limited to normalization processing, wavelength-specific characteristic correction processing, correction processing based on temperature or atmospheric pressure, and the like. If there is a Do processing, it may of course be omitted.

また、本実施形態では、演算処理部３３において測定環境に基づく調整処理として、（Ｎ−１）個の赤外線センサ１１〜１（Ｎ−１）からの各測定出力全てに対し正規化処理や参照テーブルを用いての補正処理を一律に行うように説明したが、本発明では、これに限らず、例えば、（Ｎ−１）個の赤外線センサ１１〜１（Ｎ−１）からの測定出力毎に、測定環境に基づく調整処理を変えたり、さらには、各被測定対象ガス毎に基準温度や基準圧力等の測定環境の精度に対する要求が異なっている場合には、測定出力毎に演算精度を変えて演算するようにしても良い。要は、演算処理部３３は、被測定対象ガス毎に必要とされる、ないしは最適な測定環境に合わせて、適応的ないしは選択的に調整処理を行えばよい。このようにすれば、重要な被測定対象ガスに対しては、測定環境に基づく調整処理をより細かく行うことが可能となり、効率良く測定することが可能となる。なお、演算処理部３３は、図示しないプログラムにより動作するものであるが、半導体回路等を用いてハードウエアにより構成しても勿論よい。   Further, in the present embodiment, as the adjustment processing based on the measurement environment in the arithmetic processing unit 33, normalization processing and reference are performed for all the measurement outputs from the (N-1) infrared sensors 11 to 1 (N-1). The correction processing using the table has been described as being performed uniformly. However, the present invention is not limited to this, and for example, every measurement output from (N−1) infrared sensors 11 to 1 (N−1). In addition, when the adjustment process based on the measurement environment is changed, or the requirements for the accuracy of the measurement environment such as the reference temperature and the reference pressure are different for each measurement target gas, the calculation accuracy is increased for each measurement output. You may make it calculate by changing. In short, the arithmetic processing unit 33 may perform adjustment processing adaptively or selectively in accordance with the measurement environment that is required for each measurement target gas or optimal. In this way, it is possible to finely adjust an important measurement target gas based on the measurement environment, and to measure efficiently. The arithmetic processing unit 33 is operated by a program (not shown), but may be configured by hardware using a semiconductor circuit or the like.

また、本実施形態において、ある重要な測定対象ガスに対しては、複数個の赤外線センサを用いて濃度を測定するようにして勿論良い。このようにすれば、その重要な被測定対象ガスは、複数個の赤外線センサの測定出力を用いて平均や分散等をとることにより、より精度の高い濃度を測定することが可能となる。   In the present embodiment, it is of course possible to measure the concentration of a certain important measurement target gas using a plurality of infrared sensors. In this way, it is possible to measure the concentration of the important measurement target gas with higher accuracy by taking the average, dispersion, and the like using the measurement outputs of the plurality of infrared sensors.

（第２の実施形態）
次に、本発明の第２の実施形態の大気ガス測定装置について説明する。本発明の第２の実施形態の大気ガス測定装置は、赤外線センサ１１〜１Ｎの具体的配置例を示すもので、図１と重複する部分には同一の符号を付す。 (Second Embodiment)
Next, an atmospheric gas measurement device according to a second embodiment of the present invention will be described. The atmospheric gas measurement device according to the second embodiment of the present invention shows a specific arrangement example of the infrared sensors 11 to 1N, and the same reference numerals are given to portions overlapping with those in FIG.

本発明の第２の実施形態の大気ガス測定装置おける赤外線センサの配列の一例を、図２および図３に示す。   An example of the arrangement of the infrared sensors in the atmospheric gas measurement device according to the second embodiment of the present invention is shown in FIGS.

図２は、Ｎ個の赤外線センサ１１〜１Ｎをアレイ状に配列して１つのケースに集積し、小型化したアレイ状赤外線センサユニット１Ａであり、図３は、Ｎ個の赤外線センサ１１〜１Ｎを面状に配列して１つのケースに集積し、小型化した面状赤外線センサユニット１Ｂである。   FIG. 2 shows a miniaturized array-type infrared sensor unit 1A in which N infrared sensors 11 to 1N are arranged in an array and integrated in one case, and FIG. 3 shows the N infrared sensors 11 to 1N. Is a planar infrared sensor unit 1B which is arranged in a planar shape and integrated in one case to be miniaturized.

このような本発明の第２の実施形態の大気ガス測定装置によれば、複数個の赤外線センサ１１〜１Ｎを、図２に示す１次元のアレイ状、または図３に示す例えば面状を含む２次元のアレイ状に、整列して配列されるので、赤外線センサ全体の面積を減少させ、大気ガス測定装置の小型化を図ることが可能である。また、これらの赤外線センサをケースに格納して赤外線センサユニット１Ａ、１Ｂとして提供されるので、赤外線センサの取り扱いが簡単になる。   According to the atmospheric gas measuring apparatus of the second embodiment of the present invention, the plurality of infrared sensors 11 to 1N include the one-dimensional array shown in FIG. 2 or the planar shape shown in FIG. Since they are arranged in a two-dimensional array, it is possible to reduce the area of the entire infrared sensor and to reduce the size of the atmospheric gas measurement device. Moreover, since these infrared sensors are stored in a case and provided as the infrared sensor units 1A and 1B, handling of the infrared sensors is simplified.

なお、前記第２の実施の形態の説明では、Ｎ個の赤外線センサ１１〜１Ｎを図２に示すようなアレイ状赤外線センサユニット１Ａ、または図３に示す面状赤外線センサユニット１Ｂとして配列して説明したが、本発明では、これらの配列は一例であり、これらの配列に限定されるものではなく、Ｎ個の赤外線センサ１１〜１Ｎを適当に並べても、正方状ではなく、長方形状や、円形状や、円周状等、被測定対象ガスの測定環境に合わせて任意の形状に配列するようにしても勿論良い。   In the description of the second embodiment, N infrared sensors 11 to 1N are arranged as an array infrared sensor unit 1A as shown in FIG. 2 or a planar infrared sensor unit 1B as shown in FIG. As described above, in the present invention, these arrangements are examples, and are not limited to these arrangements. Even if N infrared sensors 11 to 1N are arranged appropriately, they are not square, rectangular, Of course, it may be arranged in an arbitrary shape according to the measurement environment of the gas to be measured, such as a circular shape or a circumferential shape.

（第３の実施形態）
次に、本発明の第３の実施形態の大気ガス測定装置について説明する。本発明の第３の実施形態は第１の実施形態における波長選択手段４０を他の方法で具現化したものである。図４ないし図６は、本発明の第３の実施形態である大気ガス測定装置における波長選択手段４０を示す概略構成図である。なお、第１及び第２の実施形態図を示す図１〜図３と重複する部分には同一の符号を付す。 (Third embodiment)
Next, an atmospheric gas measurement device according to a third embodiment of the present invention will be described. In the third embodiment of the present invention, the wavelength selection means 40 in the first embodiment is embodied by another method. 4 to 6 are schematic configuration diagrams showing the wavelength selection means 40 in the atmospheric gas measurement device according to the third embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the part which overlaps FIGS. 1-3 which shows the 1st and 2nd embodiment figure.

第１の実施形態の説明では、波長選択手段４０として波長フィルター４１〜４Ｎを用いた場合について説明したが、本実施形態では、波長選択手段４０としてプリズム、回折格子のような分散型の分光素子や、フーリェ分光素子のような２光測干渉型の分光素子やエタロンのような多重干渉分光素子で代表される干渉型分光素子等の分光器を用いた場合について説明する。   In the description of the first embodiment, the case where the wavelength filters 41 to 4N are used as the wavelength selection unit 40 has been described. However, in the present embodiment, a dispersion-type spectroscopic element such as a prism or a diffraction grating is used as the wavelength selection unit 40. A case in which a spectroscope such as a two-photometric interference type spectroscopic element such as a Fourier spectroscopic element or an interference type spectroscopic element represented by a multiple interference spectroscopic element such as an etalon is used will be described.

図４は、複数の赤外線センサ１１〜１Ｎと本実施形態の波長選択手段４０との関係を示す図であり、複数の赤外線センサとしてアレイ状赤外線センサユニット１Ａを用いた場合について示している。なお、図４において、アレイ状赤外線センサユニット１Ａは、図２に示されたアレイ状赤外線センサユニットのＸ−Ｙ断面図である。   FIG. 4 is a diagram showing the relationship between the plurality of infrared sensors 11 to 1N and the wavelength selection means 40 of the present embodiment, and shows a case where the arrayed infrared sensor unit 1A is used as the plurality of infrared sensors. In FIG. 4, an arrayed infrared sensor unit 1A is an XY cross-sectional view of the arrayed infrared sensor unit shown in FIG.

図４に示すように、波長選択手段４０は透過型の波長選択手段であり、その中の結像レンズによりアレイ状赤外線センサユニット１Ａのセンサ間隔に応じて各センサ上に所望の波長の赤外光を投射することが可能なものである。   As shown in FIG. 4, the wavelength selecting means 40 is a transmission type wavelength selecting means, and an infrared ray of a desired wavelength is formed on each sensor according to the sensor interval of the arrayed infrared sensor unit 1A by an imaging lens therein. It can project light.

次に、本実施形態の波長選択手段の概略構成を説明する。図５は波長選択手段４０が分散型分光素子であるプリズムや透過型回折格子を含む場合の例を示し、図６は波長選択手段４０が分散型分光素子である反射型回折格子を含む場合の例を示す。   Next, a schematic configuration of the wavelength selection unit of the present embodiment will be described. FIG. 5 shows an example in which the wavelength selection means 40 includes a prism that is a dispersion type spectroscopic element or a transmission type diffraction grating, and FIG. 6 shows a case in which the wavelength selection means 40 includes a reflection type diffraction grating that is a dispersion type spectroscopic element. An example is shown.

回折格子を用いた場合には、回折基板へのグレーティングを適切に行うことにより必要な波長のみを選択して分光することができ、また所望の方向、位置に分光した光を投射することが出来る。このような分光型の波長選択手段４０を用いたときは分光後の光を結像レンズ５４により受光素子のサイズに応じて所望の大きさに絞ることが出来るので受光素子である赤外線センサ１１〜１Ｎは第２の実施例で説明したようにコンパクトに、集積化できる。   In the case of using a diffraction grating, it is possible to select and split only the necessary wavelength by appropriately performing grating on the diffraction substrate, and to project the split light in a desired direction and position. . When such a spectral type wavelength selecting means 40 is used, the light after the spectrum can be narrowed down to a desired size according to the size of the light receiving element by the imaging lens 54. Therefore, the infrared sensors 11 to 11 which are light receiving elements. 1N can be integrated compactly as described in the second embodiment.

図５に示すように、本実施形態の大気ガス測定装置の波長選択手段４０において、大気ガス２を通過した赤外光源１からの赤外光は、集光レンズ５１でスリット板５２のスリットに集光される。スリット板５２のスリットを通過し発散した赤外光は、コリメートレンズ５３に入って平行光となり、プリズムや透過型回折格子等の透過型分散素子４１ＮＡに入射する。透過型分散素子４１ＮＡに入射した赤外光は透過型分散素子４１ＮＡにより波長スペクトラム状に分光される。分光の大きさを結像レンズ５４によって、赤外線センサ１１〜１Ｎが集積されたアレイ状赤外線センサユニット１Ａのセンサ間隔に合わせ、夫々の赤外線センサ１１〜１Ｎ上に集光される。   As shown in FIG. 5, in the wavelength selection unit 40 of the atmospheric gas measurement device of the present embodiment, infrared light from the infrared light source 1 that has passed through the atmospheric gas 2 enters the slit of the slit plate 52 by the condenser lens 51. Focused. The infrared light diverging through the slit of the slit plate 52 enters the collimating lens 53 and becomes parallel light, and enters the transmissive dispersion element 41NA such as a prism or a transmissive diffraction grating. The infrared light incident on the transmissive dispersion element 41NA is split into a wavelength spectrum by the transmissive dispersion element 41NA. The size of the spectrum is adjusted by the imaging lens 54 in accordance with the sensor interval of the arrayed infrared sensor unit 1A in which the infrared sensors 11 to 1N are integrated, and is condensed on each of the infrared sensors 11 to 1N.

ここでは帯状の分光赤外光に対し、赤外線センサ１１〜１Ｎが集積されたアレイ状赤外線センサユニット１Ａは各センサが等間隔に配置された場合でもよく、この場合は基準信号に対応する所定の波長と被測定ガスの吸収波長とに対応させた赤外線センサの出力のみを取り出すようにすればよい。またセンサユニットを作製する時点で予め不要な波長に対応させた赤外線センサを設けないようにしてもよい。   Here, the arrayed infrared sensor unit 1A in which the infrared sensors 11 to 1N are integrated with respect to the band-shaped spectral infrared light may be arranged at equal intervals. In this case, a predetermined signal corresponding to the reference signal may be used. It is only necessary to take out only the output of the infrared sensor corresponding to the wavelength and the absorption wavelength of the gas to be measured. In addition, an infrared sensor corresponding to an unnecessary wavelength may not be provided in advance when the sensor unit is manufactured.

また、回折格子を使用する場合は回折基板へのグレーティングを適切に行うことにより必要な波長のみを選択して分光し、所望の方向、位置に分光した光を投射することが出来るので、図２のような赤外線センサを等間隔に配置したアレイ状赤外線センサユニット１Ａや図３のような二次元に配置された面状赤外線センサユニット１Ｂにも対応できる。   In addition, when a diffraction grating is used, only a necessary wavelength can be selected and dispersed by appropriately performing grating on the diffraction substrate, and the dispersed light can be projected in a desired direction and position. It is also possible to correspond to an array-shaped infrared sensor unit 1A in which infrared sensors as described above are arranged at equal intervals and a planar infrared sensor unit 1B that is two-dimensionally arranged as shown in FIG.

図６は、コリメートおよび結像の光学素子としてコリメート鏡５７および結像鏡５８を用い、分散素子として反射型分散素子４１ＮＢを用いた場合を示している。このように、光学系にミラーを用いたことにより、レンズを用いた場合の収差の影響を軽減させることができる。   FIG. 6 shows a case in which a collimating mirror 57 and an imaging mirror 58 are used as collimating and imaging optical elements, and a reflective dispersion element 41NB is used as a dispersion element. Thus, by using a mirror in the optical system, it is possible to reduce the influence of aberration when a lens is used.

上述のように、第３の実施形態では、前記第２の実施形態のようにアレイ状赤外線センサユニット１Ａ等によりＮ個の赤外線センサ１１〜１Ｎを小型化しても、各赤外線センサに選択した波長の赤外光を投射させることができる。その結果、この第３の実施形態によれば、コンパクトに且つ効率よく入射光を集光させることができる。   As described above, in the third embodiment, even if the N infrared sensors 11 to 1N are downsized by the arrayed infrared sensor unit 1A or the like as in the second embodiment, the wavelength selected for each infrared sensor. Infrared light can be projected. As a result, according to the third embodiment, incident light can be condensed in a compact and efficient manner.

このような本発明の第３の実施の形態の大気ガス測定装置によれば、波長選択手段４０にプリズムや回折格子で代表される分散型分光素子を用い赤外光を波長ごとにスペクトラム状に分解できるために、波長選択手段として小型になり、赤外線センサも小さくモジュール化できる。その結果、持ち運びのできる大気ガス測定装置を提供することができる。   According to the atmospheric gas measuring apparatus of the third embodiment of the present invention as described above, the wavelength selecting means 40 uses a dispersive spectroscopic element typified by a prism or a diffraction grating, and converts infrared light into a spectrum for each wavelength. Since it can be disassembled, the wavelength selection means becomes small, and the infrared sensor can also be made small and modular. As a result, a portable atmospheric gas measuring device can be provided.

なお、この第３の実施形態の説明では、分散型分光素子を用いた例について説明したが、エタロン等を用いた干渉型分光素子でも実現できる。   In the description of the third embodiment, an example using a dispersion type spectroscopic element has been described. However, an interference type spectroscopic element using an etalon or the like can also be realized.

（第４の実施形態）
図７は、本発明の第４の実施形態の大気ガス測定装置における赤外線センサの概略構成を示す図である。 (Fourth embodiment)
FIG. 7 is a diagram showing a schematic configuration of an infrared sensor in the atmospheric gas measurement device according to the fourth embodiment of the present invention.

本発明の第４の実施形態の大気ガス測定装置における赤外線センサとして焦電型赤外線センサを用いた例を示すもので、図１〜図６と重複する部分には同一の符号を付す。   The example which used the pyroelectric infrared sensor as an infrared sensor in the atmospheric gas measuring device of the 4th Embodiment of this invention is shown, and the same code | symbol is attached | subjected to the part which overlaps with FIGS.

この焦電型赤外線センサは、赤外線の受光波長感度特性がほぼ均一で、安定しており、基板上に焦電材料を印刷等で塗布して形成できるので多くのセンサを集積できるために小型で比較的安価に作製でき、多種類の波長つまり多種類のガスを検出することができる。ただし、この焦電型赤外線センサは電荷蓄積型であり、雑音を除去するために入射光をチョッピングし、充放電を繰り返して使用する必要がある。   This pyroelectric infrared sensor is almost uniform and stable in the wavelength sensitivity characteristics of infrared light, and can be formed by applying pyroelectric material on the substrate by printing, etc. It can be produced at a relatively low cost, and can detect many kinds of wavelengths, that is, many kinds of gases. However, this pyroelectric infrared sensor is a charge storage type, and it is necessary to chop incident light and remove and charge it in order to remove noise.

そのため、この第４の実施形態では、図７に示すように、入射光をチョッピングするためのチョッピング用孔６１ａが形成された円盤６１と、円盤６１を回転させるためのモータ７１と、波長選択手段４０の波長フィルター４１と、焦電型赤外線センサ１１Ｐｙと、焦電型赤外線センサ１１Ｐｙのセンサ信号を増幅する増幅器８１と、増幅器８１よりの矩形状の出力を正弦波に変換したり、あるいは積分して直流信号に変換する低域フィルター９１とを有している。なお、その他の図示していない構成は、図１に示す第１の実施形態の構成や、図２、図３に示す第２の実施形態の構成、さらには図４〜図６に示す第３の実施形態の構成が適用可能である。   Therefore, in the fourth embodiment, as shown in FIG. 7, a disc 61 in which a chopping hole 61a for chopping incident light is formed, a motor 71 for rotating the disc 61, and wavelength selection means 40 wavelength filter 41, pyroelectric infrared sensor 11Py, amplifier 81 for amplifying the sensor signal of pyroelectric infrared sensor 11Py, and the rectangular output from amplifier 81 is converted into a sine wave or integrated. And a low-pass filter 91 for converting to a DC signal. Other configurations not shown include the configuration of the first embodiment shown in FIG. 1, the configuration of the second embodiment shown in FIGS. 2 and 3, and the third embodiment shown in FIGS. The configuration of the embodiment can be applied.

次に動作を説明する、図７に示す本発明の第４の実施形態の大気ガス測定装置では、第１の実施形態で説明した赤外光源１からの赤外光は被測定対象物である大気ガス２を通過し、チョッピング用円盤６１に入射し、チョッピング用孔６１ａにより断続した光となる。   Next, in the atmospheric gas measuring apparatus according to the fourth embodiment of the present invention shown in FIG. 7, the infrared light from the infrared light source 1 described in the first embodiment is an object to be measured. The light passes through the atmospheric gas 2, enters the chopping disk 61, and becomes intermittent light through the chopping hole 61a.

この断続的な光は波長選択手段４０の波長フィルター４１に入射し選択された波長の赤外光のみが焦電型赤外線センサ１１Ｐｙに入射される。焦電型赤外線センサ１１Ｐｙは選択された波長の光を断続的に受光しその赤外光強度に対応した信号を増幅器８１に出力する。増幅器８１は焦電型赤外線センサ１１Ｐｙからの赤外線の矩形状出力信号を増幅し、低域フィルター９１は増幅後の焦電型赤外線センサ１１Ｐｙの出力信号を直流信号にする。   The intermittent light is incident on the wavelength filter 41 of the wavelength selecting means 40, and only the infrared light having the selected wavelength is incident on the pyroelectric infrared sensor 11Py. The pyroelectric infrared sensor 11Py intermittently receives light of a selected wavelength and outputs a signal corresponding to the infrared light intensity to the amplifier 81. The amplifier 81 amplifies the infrared rectangular output signal from the pyroelectric infrared sensor 11Py, and the low-pass filter 91 converts the amplified output signal of the pyroelectric infrared sensor 11Py into a DC signal.

なお、この低域フィルター９１からの直流信号は、本発明の第１の実施形態の大気ガス測定装置を示すブロック図である図１の増幅器２１の出力に対応するものであり、演算処理部３３に入力することにより、第１の実施の形態で示したと全く同じ方法で正規化や、補正、変換等を行って、大気ガス２中に含まれる複数個の被測定対象ガスの濃度を測定することができる。以上の例では波長選択手段および赤外線センサ毎にチョッパーが設けられている場合について説明した。   The DC signal from the low-pass filter 91 corresponds to the output of the amplifier 21 in FIG. 1, which is a block diagram showing the atmospheric gas measuring device according to the first embodiment of the present invention. , The normalization, correction, conversion, etc. are performed in the same manner as shown in the first embodiment, and the concentrations of the plurality of measurement target gases contained in the atmospheric gas 2 are measured. be able to. In the above example, the case where a chopper is provided for each wavelength selection means and infrared sensor has been described.

次に本発明の第２及び第３の実施形態で説明した図２〜図６に示すような集積化された焦電型赤外線センサの場合について、図８を用いて説明する。図８において４０は波長選択手段であり、第３の実施形態で説明した図４〜図６と同等のものである。１ＡＰｙは集積化し小型化された焦電型赤外線センサ１１Ｐｙ〜１ＮＰｙであり、第２の実施形態で説明した図２、図３のセンサユニットにおける赤外線センサの配置と同等のものである。   Next, the case of the integrated pyroelectric infrared sensor as shown in FIGS. 2 to 6 described in the second and third embodiments of the present invention will be described with reference to FIG. In FIG. 8, reference numeral 40 denotes wavelength selection means, which is equivalent to FIGS. 4 to 6 described in the third embodiment. 1APy is an integrated and miniaturized pyroelectric infrared sensor 11Py to 1NPy, which is equivalent to the arrangement of the infrared sensor in the sensor unit of FIGS. 2 and 3 described in the second embodiment.

各焦電型赤外線センサ１１Ｐｙ〜１ＮＰｙは夫々増幅器８１〜８Ｎに接続されており、増幅器８１〜８Ｎの出力は夫々低域フィルター９１〜９Ｎに接続されている。それ以外の円盤６１およびモータ７１は図７での例と同じである。なお、その他の図示していない構成は、図１に示す第１の実施形態の構成や、図２、図３に示す第２の実施形態の構成、さらには図４〜図６に示す第３の実施形態の構成が適用可能である。   The pyroelectric infrared sensors 11Py to 1NPy are connected to amplifiers 81 to 8N, respectively, and the outputs of the amplifiers 81 to 8N are connected to low-pass filters 91 to 9N, respectively. The other disk 61 and the motor 71 are the same as the example in FIG. Other configurations not shown include the configuration of the first embodiment shown in FIG. 1, the configuration of the second embodiment shown in FIGS. 2 and 3, and the third embodiment shown in FIGS. The configuration of the embodiment can be applied.

図８においてモータ７１により回転する円盤６１のチョッピング用孔６１ａを通って断続的な赤外光が波長手段４０に入り、ここで選択された複数の波長の断続的な赤外光を夫々の波長に対応した焦電型赤外線センサ１１Ｐｙ〜１ＮＰｙへ入射する。焦電型赤外線センサ１１Ｐｙ〜１ＮＰｙは、夫々選択された波長の光を断続的に受光しその赤外光強度に対応した信号を増幅器８１〜８Ｎに出力する。増幅器８１〜８Ｎは焦電型赤外線センサ１１Ｐｙ〜１ＮＰｙからの赤外線の矩形状出力信号を増幅し、低域フィルター９１〜９Ｎは増幅後の焦電型赤外線センサ１１Ｐｙ〜１ＮＰｙの出力信号を直流信号にする。   In FIG. 8, intermittent infrared light enters the wavelength means 40 through the chopping hole 61a of the disk 61 rotated by the motor 71, and intermittent infrared light having a plurality of wavelengths selected here is converted into each wavelength. Are incident on the pyroelectric infrared sensors 11Py to 1NPy corresponding to. The pyroelectric infrared sensors 11Py to 1NPy intermittently receive light of a selected wavelength and output signals corresponding to the infrared light intensity to the amplifiers 81 to 8N. The amplifiers 81 to 8N amplify the infrared rectangular output signals from the pyroelectric infrared sensors 11Py to 1NPy, and the low-pass filters 91 to 9N convert the amplified output signals of the pyroelectric infrared sensors 11Py to 1NPy into DC signals. To do.

なお、この低域フィルター９１〜９Ｎよりの直流信号は、本発明の第１の実施形態の大気ガス測定装置を示すブロック図である図１の増幅器２１〜２Ｎの出力に対応するものであり、演算処理部３３に入力することにより、第１の実施の形態で示したと全く同じ方法で正規化や、補正、変換等を行って、大気ガス２中に含まれる複数個の被測定対象ガスの濃度を測定することができる。   The DC signals from the low-pass filters 91 to 9N correspond to the outputs of the amplifiers 21 to 2N in FIG. 1, which is a block diagram showing the atmospheric gas measuring device according to the first embodiment of the present invention. By inputting to the arithmetic processing unit 33, normalization, correction, conversion, etc. are performed in exactly the same manner as shown in the first embodiment, and a plurality of measurement target gases contained in the atmospheric gas 2 are detected. The concentration can be measured.

このような本発明の第４の実施形態の大気ガス測定装置によれば、焦電型赤外線センサとセンサ信号の正規化、補正、変換方法を用いるので、安定して、小型でかつ比較的安価に、簡単かつ正確により多くの種類の被測定対象ガスの濃度を一度に測定することができる。   According to the atmospheric gas measuring apparatus of the fourth embodiment of the present invention, since the pyroelectric infrared sensor and the sensor signal normalization, correction, and conversion method are used, it is stable, small and relatively inexpensive. In addition, it is possible to easily and accurately measure the concentrations of many types of gases to be measured at once.

なお本実施例では光を断続した後に波長選択手段４０のフィルター４１で赤外光を選択する例について説明したが、図７においてフィルター４１をチョッピング用孔６１ａが形成された円盤６１の左側に設け、選択された赤外光のみを断続してもよい。また本実施例では入射光をチョッピングする手段としてチョッピング用孔６１ａが形成された円盤６１と、円盤６１を回転させるためのモータ７１とを用いた例について説明したが、液晶による光の断続、つまり液晶チョッパーや圧電を用いた圧電チョッパーを用いても実現でき、これを用いることによりさらに小型化できる。   In the present embodiment, an example in which infrared light is selected by the filter 41 of the wavelength selection means 40 after the light is interrupted has been described. However, in FIG. 7, the filter 41 is provided on the left side of the disk 61 in which the chopping hole 61a is formed. Only the selected infrared light may be interrupted. In the present embodiment, an example using the disk 61 in which the chopping hole 61a is formed and the motor 71 for rotating the disk 61 as means for chopping incident light has been described. This can also be realized by using a liquid crystal chopper or a piezoelectric chopper using a piezoelectric element, and the size can be further reduced by using this.

なお、上記第１〜第４の実施の形態の受光素子である赤外線センサ１１〜１Ｎとしては熱型と量子型に大別されるが本発明ではどちらの赤外線センサでも適用できる。   The infrared sensors 11 to 1N, which are the light receiving elements of the first to fourth embodiments, are roughly classified into a thermal type and a quantum type, but either infrared sensor can be applied in the present invention.

また上記第１〜第４の実施の形態の説明では、本発明のガス測定装置の実施形態として、大気ガス２中に含まれる炭酸ガス等の地球温暖化ガスや、ＮＯｘ等の排気ガス等の複数種類の被測定対象ガスの濃度を測定する大気ガス測定装置について説明したが、本発明では、このような大気ガス２に含まれる複数種類の被測定対象ガスのガス測定装置に限られるものではなく、それ以外の複数種類の被測定対象ガスの濃度を測定するガス測定装置であっても良い。要は、選択された複数個の波長に対応して設けられた複数個の赤外線センサにより複数種類の被測定対象ガスを測定して、当該複数種類の被測定対象ガスの濃度を測定するものであれば、いかなる複数種類の被測定対象ガスの濃度測定にも本発明は適用可能である。   In the description of the first to fourth embodiments, as an embodiment of the gas measuring device of the present invention, a global warming gas such as carbon dioxide contained in the atmospheric gas 2 or an exhaust gas such as NOx is used. Although the atmospheric gas measuring device for measuring the concentrations of a plurality of types of measurement target gases has been described, the present invention is not limited to such a gas measurement device for a plurality of types of measurement target gases contained in the atmospheric gas 2. Alternatively, it may be a gas measuring device that measures the concentrations of other types of gases to be measured. In short, a plurality of types of measurement target gases are measured by a plurality of infrared sensors provided corresponding to a plurality of selected wavelengths, and the concentrations of the plurality of types of measurement target gases are measured. The present invention can be applied to the concentration measurement of any kind of plural gases to be measured.

以上のように、本発明は、簡単かつ正確に複数種類の測定対象ガスを測定することが可能な効果を有し、大気ガス測定装置および方法等のガス測定装置およびガス測定方法等に好適である。   As described above, the present invention has an effect capable of easily and accurately measuring a plurality of types of measurement target gases, and is suitable for a gas measurement device and a gas measurement method such as an atmospheric gas measurement device and method. is there.

本発明の第１の実施形態の大気ガス測定装置の構成を示すブロック図The block diagram which shows the structure of the atmospheric gas measuring device of the 1st Embodiment of this invention 本発明の第２の実施形態の大気ガス測定装置における赤外線センサユニットの例を示す構成図The block diagram which shows the example of the infrared sensor unit in the atmospheric gas measuring device of the 2nd Embodiment of this invention 本発明の第２の実施形態の大気ガス測定装置における赤外線センサユニットの他の例を示す構成図。The block diagram which shows the other example of the infrared sensor unit in the atmospheric gas measuring device of the 2nd Embodiment of this invention. 本発明の第３の実施形態の大気ガス測定装置の波長選択手段の概略構成を示すブロック図The block diagram which shows schematic structure of the wavelength selection means of the atmospheric gas measuring apparatus of the 3rd Embodiment of this invention 本発明の第３の実施形態の大気ガス測定装置の波長選択手段の概略構成を示すブロック図The block diagram which shows schematic structure of the wavelength selection means of the atmospheric gas measuring apparatus of the 3rd Embodiment of this invention 本発明の第３の実施形態の大気ガス測定装置の他の波長選択手段の概略構成を示すブロック図The block diagram which shows schematic structure of the other wavelength selection means of the atmospheric gas measuring device of the 3rd Embodiment of this invention 本発明の第４の実施形態の大気ガス測定装置おける焦電型赤外線センサの構成を示す構成図The block diagram which shows the structure of the pyroelectric infrared sensor in the atmospheric gas measuring device of the 4th Embodiment of this invention 本発明の第４の実施形態の大気ガス測定装置おける焦電型赤外線センサの他の例を示す構成図The block diagram which shows the other example of the pyroelectric infrared sensor in the atmospheric gas measuring device of the 4th Embodiment of this invention

符号の説明Explanation of symbols

１ 赤外光源
２ 大気ガス
１０ 大気ガス測定装置（ガス測定装置）
１１〜１Ｎ 赤外線センサ
２１〜２Ｎ 増幅器
３１ 温度センサ
３２ 気圧センサ
３３ 演算処理部（処理部）
３４ 記憶部
１Ａ アレイ状赤外線センサユニット
１Ｂ 面状赤外線センサユニット
４０ 波長選択手段
４１〜４Ｎ フィルター等の波長選択素子
４１ＮＡ プリズム等の透過型分散素子
４１ＮＢ 反射型回折格子等の反射型分散素子
５１ 集光光学系
５２ スリット板
５３、５７ コリメート光学系
５４、５８ 結像光学系
６１ 円盤
７１ モータ
１１Ｐｙ〜１ＮＰｙ 焦電型赤外線センサ
１ＡＰｙ アレイ状焦電型赤外線センサユニット
８１〜８Ｎ 増幅器
９１〜９Ｎ 低域フィルター 1 Infrared light source 2 Atmospheric gas 10 Atmospheric gas measuring device (gas measuring device)
11 to 1N infrared sensor 21 to 2N amplifier 31 temperature sensor 32 barometric pressure sensor 33 arithmetic processing unit (processing unit)
34 Storage Unit 1A Arrayed Infrared Sensor Unit 1B Planar Infrared Sensor Unit 40 Wavelength Selection Unit 41 to 4N Wavelength Selection Element such as Filter 41NA Transmission Dispersion Element such as Prism 41NB Reflection Dispersion Element such as Reflection Type Diffraction Grating 51 Condensing Optical system 52 Slit plate 53, 57 Collimating optical system 54, 58 Imaging optical system 61 Disk 71 Motor 11Py-1NPy Pyroelectric infrared sensor 1APy Array-type pyroelectric infrared sensor unit 81-8N Amplifier 91-9N Low-pass filter

Claims (15)

所定の波長の赤外光を検出する基準赤外線センサを含み、赤外光源からの赤外光を、被測定ガスを介して複数の異なる波長の光をそれぞれ検出する複数の赤外線センサと、
前記複数の赤外線センサのうち、少なくとも、測定対象となるガスの固有赤外線吸収波長の赤外光を受光する赤外線センサの検出信号を、前記基準赤外線センサの検出信号に基づいて正規化する測定対象正規化手段と、
を備えるガス測定装置。 Including a reference infrared sensor for detecting infrared light of a predetermined wavelength, and a plurality of infrared sensors that respectively detect infrared light from an infrared light source through a gas to be measured and a plurality of different wavelengths of light;
Among the plurality of infrared sensors, at least a measurement target normalization that normalizes a detection signal of an infrared sensor that receives infrared light having an intrinsic infrared absorption wavelength of a gas to be measured based on the detection signal of the reference infrared sensor And
A gas measuring device comprising: 前記複数の赤外線センサはそれぞれ異なる感度波長を有する請求項１記載のガス測定装置。   The gas measuring device according to claim 1, wherein the plurality of infrared sensors have different sensitivity wavelengths. 前記赤外光源からの赤外光から複数の異なる波長を選択する波長選択手段をさらに備え、前記複数の赤外線センサは前記選択された複数の異なる波長の光をそれぞれ検出する請求項１または２記載のガス測定装置。   The wavelength selecting means for selecting a plurality of different wavelengths from the infrared light from the infrared light source is further provided, and the plurality of infrared sensors respectively detect the light of the selected plurality of different wavelengths. Gas measuring device. 前記波長選択手段は前記赤外光源からの赤外光を分光して前記異なる波長の光を出力する分光器を含む請求項３記載のガス測定装置。   The gas measuring apparatus according to claim 3, wherein the wavelength selection unit includes a spectroscope that splits infrared light from the infrared light source and outputs the light having the different wavelength. 前記波長選択手段は、前記複数の赤外線センサに対応して設けられた複数の赤外線フィルタを含む請求項３記載のガス測定装置。   The gas measuring device according to claim 3, wherein the wavelength selection unit includes a plurality of infrared filters provided corresponding to the plurality of infrared sensors. 前記赤外光源の発光波長出力特性、前記波長選択手段の各選択波長毎の波長選択特性、および前記複数の赤外線センサの各センサ毎の受光波長感度特性のうち、少なくとも一つの特性に基づいて、波長毎の発光出力、選択波長透過率および各検出波長毎の受光波長感度が略均一になるように前記赤外線センサからの出力信号を補正する受発光波長特性補正手段をさらに備える請求項３ないし５記載のガス測定装置。   Based on at least one of the emission wavelength output characteristics of the infrared light source, the wavelength selection characteristics for each selected wavelength of the wavelength selection means, and the received wavelength sensitivity characteristics for each of the plurality of infrared sensors, 6. A light receiving / emitting wavelength characteristic correcting means for correcting an output signal from the infrared sensor so that a light emission output for each wavelength, a selected wavelength transmittance, and a light receiving wavelength sensitivity for each detection wavelength are substantially uniform. The gas measuring device as described. 前記正規化される前の信号に関して、前記発光波長出力特性、前記波長選択特性および前記受光波長感度特性のうち少なくとも一つと、前記被測定ガスの赤外線センサ検出信号との相関に基づいて作成された受発光波長特性補正テーブルが記憶された受発光波長特性補正テーブル記憶手段をさらに備え、
前記受発光波長特性補正手段は、前記受発光波長特性補正テーブルを参照して前記正規化される前の信号の補正を行う請求項６に記載のガス測定装置。 The signal before normalization was created based on a correlation between at least one of the emission wavelength output characteristic, the wavelength selection characteristic, and the light receiving wavelength sensitivity characteristic and an infrared sensor detection signal of the gas to be measured. A light receiving / emitting wavelength characteristic correction table storing means storing a light receiving / emitting wavelength characteristic correction table;
The gas measuring apparatus according to claim 6, wherein the light receiving / emitting wavelength characteristic correcting unit corrects the signal before normalization with reference to the light receiving / emitting wavelength characteristic correction table. 前記測定時の被測定ガスの温度を検出する温度センサ、および前記測定時の被測定ガスの圧力を検出する圧力センサのうち、少なくとも一方を有する測定環境検出手段と、
前記測定環境検出手段の検出結果に基づいて、前記正規化された信号が環境変化に依存しないように環境変化に対して補正する測定環境特性補正手段と、をさらに備える請求項１ないし７のいずれか一項記載のガス測定装置。 A measurement environment detection means having at least one of a temperature sensor for detecting the temperature of the gas under measurement at the time of measurement and a pressure sensor for detecting the pressure of the gas under measurement at the time of measurement;
The measurement environment characteristic correcting means for correcting the environmental change so that the normalized signal does not depend on the environmental change based on the detection result of the measurement environment detecting means. The gas measuring device according to claim 1. 前記正規化された信号に関して、前記温度および前記圧力のうち少なくとも一方と前記被測定ガスの濃度との相関に基づいて作成された測定環境特性補正テーブルが記憶された測定環境特性補正テーブル記憶手段をさらに備え、
前記測定環境特性補正手段は、前記測定環境特性補正テーブルを参照して前記正規化された信号の測定環境特性補正を行う請求項８に記載のガス測定装置。 Measurement environment characteristic correction table storage means for storing a measurement environment characteristic correction table created based on the correlation between at least one of the temperature and the pressure and the concentration of the gas to be measured with respect to the normalized signal; In addition,
The gas measurement apparatus according to claim 8, wherein the measurement environment characteristic correction unit performs measurement environment characteristic correction of the normalized signal with reference to the measurement environment characteristic correction table. 前記正規化および前記補正がなされた信号を、前記測定対象ガス毎に濃度信号に変換する濃度変換手段をさらに備える請求項８または９に記載のガス測定装置。   The gas measurement device according to claim 8, further comprising a concentration conversion unit configured to convert the signal subjected to the normalization and the correction into a concentration signal for each measurement target gas. 前記測定対象ガス毎に、前記正規化された信号の特性と前記測定対象ガス濃度との相関を示す濃度変換テーブルが記憶された濃度変換テーブル記憶手段をさらに備え、
前記濃度変換手段は前記濃度変換テーブルを参照して前記濃度変換を行う請求項１０記載のガス測定装置。 Concentration conversion table storage means for storing a concentration conversion table indicating a correlation between the normalized signal characteristic and the measurement target gas concentration for each measurement target gas,
The gas measuring device according to claim 10, wherein the concentration conversion unit performs the concentration conversion with reference to the concentration conversion table. 前記所定の波長は、被測定ガス中の赤外線透過率が所定値以上となる波長である請求項１ないし１１のいずれか一項記載のガス測定装置。   The gas measuring apparatus according to any one of claims 1 to 11, wherein the predetermined wavelength is a wavelength at which an infrared transmittance in the gas to be measured is a predetermined value or more. 前記複数の赤外線センサが、１次元または２次元のアレイ状に配置されてケースに格納された赤外線センサユニットを有する請求項１ないし１２のいずれか一項記載のガス測定装置。   The gas measuring device according to any one of claims 1 to 12, wherein the plurality of infrared sensors include an infrared sensor unit arranged in a one-dimensional or two-dimensional array and stored in a case. 前記複数の赤外線センサは、焦電型赤外線センサである請求項１ないし１３のいずれか一項記載のガス測定装置。   The gas measuring device according to claim 1, wherein the plurality of infrared sensors are pyroelectric infrared sensors. 被測定ガスを通過させた赤外光源からの赤外光より所定の波長の光と、測定対象となるガスの固有赤外線吸収波長の赤外光を検出するステップと、
前記測定対象となるガスの固有赤外線吸収波長に対応した赤外線センサの検出信号を、前記基準赤外線センサの検出信号に基づいて正規化するステップと、
を備えるガス測定方法。 Detecting light of a predetermined wavelength from infrared light from an infrared light source that has passed the gas to be measured, and infrared light having an intrinsic infrared absorption wavelength of the gas to be measured;
Normalizing the detection signal of the infrared sensor corresponding to the intrinsic infrared absorption wavelength of the gas to be measured based on the detection signal of the reference infrared sensor;
A gas measurement method comprising:

Images