JPH05164620A - Optical measuring apparatus - Google Patents

Abstract

PURPOSE:To obtain the sense signal at a sufficient level by alleviating the fluctuation of the output of a sensor including an optional system in parallel with the measurement of a body to be measured. CONSTITUTION:A reference light source 3c for emitting a reference signal, whose level is preset, is embedded in a detecting window 1. The reference light is superimposed or radiation energy, which is condensed through a light condensing means by the opening and closing of a switch 3a. A sensor 5 detects the radiation energy when the reference light is turned ON and turned OFF. A comparing and operating means 7b operates the level difference of the detected signals when the light is turned ON and turned OFF. A gain correcting means 7c corrects the gain of an amplifier 6 to the upper value so that the operated level difference agrees with the level of the reference light.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、例えば放射温度計、水
分計等のように被測定体に光を投光して反射してくる放
射エネルギーに基づいて被測定体の表面温度や成分等を
測定する光学的測定装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the surface temperature and components of an object to be measured based on the radiant energy reflected by projecting light onto the object to be measured, such as a radiation thermometer and a moisture meter. The present invention relates to an optical measuring device for measuring.

【０００２】[0002]

【従来の技術】光学的測定装置として放射温度計を例に
とって説明すると、放射温度計は被測定体からの放射エ
ネルギーを装置本体の一側部に設けられた検出窓を介し
て光学系により集光し、この集光された放射エネルギー
を測定波長および比較波長のフィルタが配設された回転
板に導き、回転板でチョッパされフィルタを透過して検
出素子により検出された光に基づいて被測定体の表面温
度を測定している。2. Description of the Related Art A radiation thermometer will be described as an example of an optical measuring apparatus. The radiation thermometer collects the radiant energy from the object to be measured by an optical system through a detection window provided on one side of the apparatus body. Light is emitted, and the condensed radiant energy is guided to a rotating plate on which a filter for the measurement wavelength and a filter for the comparison wavelength are arranged, choppered by the rotating plate, transmitted through the filter, and measured based on the light detected by the detection element. The surface temperature of the body is measured.

【０００３】ところで、この種の放射温度計では、検出
素子として硫化鉛（ＰｂＳ）光導電素子が使用されてい
るものが知られているが、硫化鉛光導電素子は時間とと
もに出力が変動してドリフトを生じ易く、このドリフト
は測定誤差に直接影響を及ぼすという問題があった。こ
のため、従来では外部の黒体炉の放射率を基準として検
出信号の校正を行い、ドリフトの補償をしていた。Incidentally, in this type of radiation thermometer, it is known that a lead sulfide (PbS) photoconductive element is used as a detection element, but the output of the lead sulfide photoconductive element varies with time. There is a problem that a drift is likely to occur, and this drift directly affects the measurement error. Therefore, conventionally, the detection signal is calibrated with reference to the emissivity of an external black body furnace to compensate for the drift.

【０００４】[0004]

【発明が解決しようとする課題】従って、従来の放射温
度計では、検出素子に出力変動が起きてドリフトが生じ
た場合、その都度被測定体の測定を中断してドリフトの
補償を行っていたので、作業効率が悪く効率的な測定が
行えなかった。Therefore, in the conventional radiation thermometer, when the output of the detection element fluctuates and drift occurs, the measurement of the object to be measured is interrupted each time to compensate the drift. Therefore, the work efficiency was poor and efficient measurement could not be performed.

【０００５】また、この種の放射温度計では、被測定体
からの放射エネルギーが検出素子に検出されるまでの間
に光学系を通過するため、光学系にゴミ、塵等が付着し
て汚れると、検出信号のレベルが低下して信号処理を行
うのに十分なレベルの検出信号を得ることができなかっ
た。Further, in this type of radiation thermometer, since the radiant energy from the object to be measured passes through the optical system until it is detected by the detecting element, dust and dirt adhere to the optical system and become contaminated. As a result, the level of the detection signal is lowered and it is not possible to obtain a detection signal of a level sufficient for signal processing.

【０００６】そこで、本発明は上述した問題点に鑑みて
なされたものであって、その目的は、被測定体の測定に
並行して光学系を含めた検出素子の出力変動を軽減して
十分なレベルの検出信号が得られる光学的測定装置を提
供することにある。Therefore, the present invention has been made in view of the above-mentioned problems, and an object thereof is to reduce output fluctuations of a detection element including an optical system in parallel with measurement of an object to be measured. An object of the present invention is to provide an optical measuring device capable of obtaining detection signals of various levels.

【０００７】[0007]

【課題を解決するための手段】上記目的を達成するた
め、本発明による光学的測定装置は、被測定体からの放
射エネルギーを取り込む検出窓の近くに配置され、前記
放射エネルギーに重畳するための予めレベル設定された
基準光を断続的に出力する基準光出力手段と、前記基準
光の点灯時および消灯時の放射エネルギーを検出する検
出手段と、該検出手段が検出した前記基準光の点灯時お
よび消灯時の検出信号のレベル差を演算する演算手段
と、該演算手段が演算したレベル差を前記基準光のレベ
ル値と一致するように補正する補正手段とを備えたこと
を特徴としている。In order to achieve the above object, an optical measuring device according to the present invention is arranged near a detection window for taking in radiant energy from an object to be measured and superimposes it on the radiant energy. Reference light output means for intermittently outputting the reference light whose level is set beforehand, detection means for detecting radiant energy when the reference light is turned on and off, and when the reference light detected by the detection means is turned on And a calculating means for calculating the level difference of the detection signal when the light is turned off, and a correcting means for correcting the level difference calculated by the calculating means so as to match the level value of the reference light.

【０００８】[0008]

【作用】被測定体からの放射エネルギーは検出窓から取
り込まれ、この検出窓の近くに配置された基準光出力手
段は、予めレベル設定された基準光を断続的に出射して
放射エネルギーに重畳する。検出手段は基準光の点灯時
および消灯時の放射エネルギーを検出する。演算手段は
検出手段が検出した基準光の点灯時および消灯時の検出
信号のレベル差を演算する。補正手段はこのレベル差を
基準光のレベルと一致するように例えば増幅器のゲイン
等を補正する。The radiant energy from the object to be measured is taken in through the detection window, and the reference light output means arranged in the vicinity of the detection window intermittently emits the reference light whose level is set in advance and superimposes it on the radiant energy. To do. The detection means detects the radiant energy when the reference light is turned on and off. The calculation means calculates the level difference of the detection signal when the reference light detected by the detection means is turned on and off. The correction means corrects, for example, the gain of the amplifier so that this level difference matches the level of the reference light.

【０００９】[0009]

【実施例】図１は本発明による光学的測定装置の一実施
例を示す図、図２は同測定装置による動作時の波形図で
ある。この実施例による光学的測定装置は、検出窓１、
集光手段２、基準光出力手段３、回転セクタ４、検出素
子（検出手段）５、増幅器６、処理制御手段７を装置本
体８に備えて構成されている。1 is a diagram showing an embodiment of an optical measuring device according to the present invention, and FIG. 2 is a waveform diagram during operation of the measuring device. The optical measuring device according to this embodiment includes a detection window 1,
The apparatus main body 8 is configured to include a light collecting unit 2, a reference light output unit 3, a rotating sector 4, a detection element (detection unit) 5, an amplifier 6, and a processing control unit 7.

【００１０】検出窓１は透光性を有する部材、例えばガ
ラスで形成されており、測定時に被測定体Ｗに向くよう
に装置本体８の一側部に配設されている。集光手段２は
例えば単一の対物レンズ、凹面鏡と凸面鏡の組み合わせ
によって構成されるもので、被測定体Ｗからの放射エネ
ルギーを検出素子６の検出面６ａに結像するように集光
している。基準光出力手段３はスイッチ３ａを介して基
準電源３ｂから供給される電力により基準光源３ｃを点
灯して基準光を回転セクタ４に出射している。さらに説
明すると、基準光源３ｃは検出窓１に埋設または近接し
て側部に設けられており、基準光は検出窓１の中心に向
かって出射されるようになっている。なお、基準光源３
ｃは検出器１の近く後方の集光手段２と回転セクタ４と
の間等の光軸Ｌ−Ｌから離れた位置に配設してもよく、
この場合、光軸Ｌ−Ｌ上にハーフミラーを配設する。こ
のハーフミラーは集光手段２によって集光された被測定
体Ｗからの放射エネルギーを検出素子５側に透過させる
とともに、基準光出力手段３からの基準光が入射された
場合には、この基準光を９０度反射させて放射エネルギ
ーに重畳し、検出素子５側に反射させている。The detection window 1 is formed of a translucent member such as glass, and is arranged on one side of the apparatus main body 8 so as to face the object W to be measured at the time of measurement. The condensing unit 2 is composed of, for example, a single objective lens, a combination of a concave mirror and a convex mirror, and condenses the radiant energy from the measured object W so as to form an image on the detection surface 6 a of the detection element 6. There is. The reference light output means 3 lights the reference light source 3c by the electric power supplied from the reference power source 3b via the switch 3a, and emits the reference light to the rotating sector 4. More specifically, the reference light source 3c is embedded in or close to the detection window 1 and is provided on the side portion, and the reference light is emitted toward the center of the detection window 1. The reference light source 3
c may be arranged near the detector 1 at a position apart from the optical axis L-L, such as between the light collecting means 2 and the rotating sector 4 at the rear,
In this case, a half mirror is arranged on the optical axis L-L. This half mirror transmits the radiant energy from the object to be measured W condensed by the condensing means 2 to the detecting element 5 side, and when the reference light from the reference light output means 3 is incident, this reference is used. The light is reflected by 90 degrees, superimposed on the radiant energy, and reflected on the detection element 5 side.

【００１１】回転セクタ４は測定波長および比較波長の
光を透過するフィルタ４ａが円板４ｂ上に配設されたも
ので、集光手段２から入射される光をチョッピングし、
測定波長および比較波長の光をフィルタ４ａより透過し
て検出素子５に出射している。The rotating sector 4 is provided with a filter 4a which transmits the light of the measurement wavelength and the light of the comparison wavelength on the disc 4b, and chops the light incident from the light converging means 2.
The light of the measurement wavelength and the light of the comparison wavelength are transmitted through the filter 4a and emitted to the detection element 5.

【００１２】検出素子５は例えば硫化鉛光導電素子で構
成され、回転セクタ４の各フィルタ４ａを透過した光を
受光検出して増幅器６に出力している。増幅器６は検出
素子５が受光検出して変換された電気信号を所定ゲイン
により所定レベルまで増幅して処理制御手段７に入力し
ている。処理制御手段７はスイッチ駆動手段７ａ、比較
演算手段（演算手段）７ｂ、補正手段７ｃを備えて構成
され、スイッチ３ａの駆動を制御するとともに、増幅器
６より入力される信号に基づいて増幅器６のゲインを適
正値に補正している。The detection element 5 is composed of, for example, a lead sulfide photoconductive element, and detects the light transmitted through each filter 4a of the rotating sector 4 and outputs it to the amplifier 6. The amplifier 6 amplifies the electric signal detected by the detection element 5 by detecting the light received and converted to a predetermined level by a predetermined gain, and inputs it to the processing control means 7. The processing control means 7 is configured to include a switch driving means 7a, a comparison calculation means (calculation means) 7b, and a correction means 7c. The gain is corrected to an appropriate value.

【００１３】さらに説明すると、スイッチ駆動手段７ａ
は基準光出力手段３のスイッチ３ａを予め設定された時
間Ｔ置きに所定時間ｔだけ閉状態に切り換える制御を行
っている。なお、スイッチ３ａを閉状態にする周期Ｔ
と、閉状態に切り換えて保持する時間ｔは測定前に可変
設定できるようになっている。比較演算手段７ｂは検出
素子５が検出した基準光点灯時の信号のレベルＶ（Ｅ
ｔ）＋Ｖ（Ｅｒ）と、基準光消灯時の信号のレベルＶ
（Ｅｔ）とのレベル差αを演算し、さらに、このレベル
差αと基準光のレベルＶ（Ｅｒ）とを比較してその差β
を演算し、その結果を差信号として補正手段７ｃに出力
している。補正手段８ｃは比較演算手段８ｂより入力さ
れる差信号に基づいて基準光に対する変動分β（＝α−
Ｖ（Ｅｒ））が無くなるように、増幅器６のゲイン等を
適正値に補正している。ここで、信号のレベル差βは検
出素子５の出力変動によるドリフトと、検出窓１、集光
手段２による光学系の汚れ等により生ずるものである。To explain further, the switch driving means 7a
Controls the switch 3a of the reference light output means 3 to be closed for a predetermined time t at every preset time T. In addition, a cycle T for closing the switch 3a
Then, the time t for switching to the closed state and holding it can be variably set before the measurement. The comparison calculation means 7b detects the level V (E of the signal detected by the detection element 5 when the reference light is lit.
t) + V (Er) and the signal level V when the reference light is off
(Et), the level difference α is calculated, and this level difference α is compared with the level V (Er) of the reference light to obtain the difference β.
Is calculated, and the result is output to the correction means 7c as a difference signal. The correction unit 8c uses the difference signal input from the comparison calculation unit 8b to calculate a variation β (= α−) relative to the reference light.
The gain and the like of the amplifier 6 are corrected to appropriate values so that V (Er)) disappears. Here, the signal level difference β is caused by the drift due to the output fluctuation of the detection element 5, the contamination of the optical system by the detection window 1 and the condensing means 2, and the like.

【００１４】次に、上記のように構成された光学的測定
装置の動作について説明する。被測定体Ｗの測定を行う
にあたっては、まず、検出窓１から集光される光を遮断
し、スイッチ３ａを閉状態にして基準光を点灯させて基
準光のレベルＶ（Ｅｒ）を検出してスイッチ３ａを開状
態に戻す。この状態で被測定体Ｗの測定を開始する。ま
ず、スイッチ３ａが開状態で基準光が消灯している場合
には、被測定体Ｗからの放射エネルギーは検出窓１を介
して集光手段２により集光され、さらに回転セクタ４の
各フィルタ４ａを透過して検出素子５に検出される。Next, the operation of the optical measuring device configured as described above will be described. In measuring the object to be measured W, first, the light condensed from the detection window 1 is shut off, the switch 3a is closed, and the reference light is turned on to detect the level V (Er) of the reference light. Switch 3a to the open state. In this state, the measurement of the measured object W is started. First, when the switch 3a is in the open state and the reference light is off, the radiant energy from the object to be measured W is condensed by the condensing means 2 via the detection window 1, and each filter of the rotating sector 4 is also collected. The light is transmitted through 4a and detected by the detection element 5.

【００１５】次に、スイッチ３ａが開状態から閉状態に
切り換わると、基準電源３ｂからの電力の供給により基
準電源３ｃが点灯して基準光が検出窓１の中心に向かっ
て出射される。そして、この基準光は検出窓１において
被測定体Ｗから集光された光に重畳されて回転セクタ４
に導かれ、各フィルタ４ａを透過して検出素子５に検出
される。Next, when the switch 3a is switched from the open state to the closed state, the reference power source 3c is turned on by the power supplied from the reference power source 3b, and the reference light is emitted toward the center of the detection window 1. Then, this reference light is superimposed on the light condensed from the object to be measured W in the detection window 1 to be combined with the rotating sector 4.
Is transmitted to each filter 4a and detected by the detection element 5.

【００１６】そして、比較演算手段７ｂは基準光の消灯
時および点灯時の検出信号のレベル差αを演算した後、
このレベル差αと基準光のレベルＶ（Ｅｒ）との差βを
演算し、その結果を差信号として補正手段７ｃに出力す
る。ここで、差βが無ければ、すなわち、α＝Ｖ（Ｅ
ｒ）であれば、変動分βが０と判別される。Then, the comparison calculation means 7b calculates the level difference α of the detection signal when the reference light is turned off and when it is turned on, and then,
A difference β between the level difference α and the level V (Er) of the reference light is calculated, and the result is output to the correction means 7c as a difference signal. Here, if there is no difference β, that is, α = V (E
If it is r), it is determined that the variation β is 0.

【００１７】もし、変動分βがある場合には、補正手段
７ｃは比較演算手段７ｂからの差信号に基づいて基準光
に対する変動分βが無くなるように、増幅器６のゲイン
等を増減して適正値に補正する。If there is a fluctuation β, the correcting means 7c appropriately increases or decreases the gain of the amplifier 6 or the like so that the fluctuation β with respect to the reference light is eliminated based on the difference signal from the comparison calculating means 7b. Correct to the value.

【００１８】従って、上述した実施例では、基準光の消
灯時および点灯時の検出信号のレベル差に基づいて基準
光のレベルに対する変動が無くなるように増幅器６のゲ
イン尚を増減して補正を行っているので、被測定体Ｗの
測定を中断することなく、この測定動作に並行して光学
系を含めた検出素子の出力変動を軽減してドリフト補償
を行うことができる。Therefore, in the above-mentioned embodiment, the gain of the amplifier 6 is increased or decreased so as to eliminate the fluctuation with respect to the level of the reference light based on the level difference between the detection signals when the reference light is off and when it is on. Therefore, it is possible to perform drift compensation by interrupting the output fluctuation of the detection element including the optical system in parallel with the measurement operation without interrupting the measurement of the measured object W.

【００１９】ところで、上述した実施例において、基準
光の点灯時の検出信号と比較される基準光の消灯時の検
出信号は、基準光の点灯前後の平均によるものでもよ
い。By the way, in the above-described embodiment, the detection signal when the reference light is turned off, which is compared with the detection signal when the reference light is turned on, may be an average before and after the reference light is turned on.

【００２０】[0020]

【発明の効果】以上説明したように、本発明の光学的測
定装置によれば、被測定体の測定に並行して光学系を含
めた検出素子の出力変動を軽減して十分なレベルの検出
信号を得ることができる。As described above, according to the optical measuring apparatus of the present invention, the fluctuation of the output of the detecting element including the optical system is reduced in parallel with the measurement of the object to be measured to detect a sufficient level. You can get a signal.

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

【図１】本発明による光学的測定装置の一実施例を示す
ブロック構成図FIG. 1 is a block diagram showing an embodiment of an optical measuring device according to the present invention.

【図２】同測定装置による動作時の波形図[Fig. 2] Waveform diagram during operation by the measurement device

【符号の説明】[Explanation of symbols]

１…検出窓、３…基準光出力手段、５…検出素子（検出
手段）、７ｂ…比較演算手段（演算手段）、７ｃ…補正
手段、Ｗ…被測定体。DESCRIPTION OF SYMBOLS 1 ... Detection window, 3 ... Reference light output means, 5 ... Detection element (detection means), 7b ... Comparison calculation means (calculation means), 7c ... Correction means, W ... Measured object.

───────────────────────────────────────────────────── フロントページの続き (72)発明者 廿楽 雅宏 東京都板橋区熊野町32番８号 株式会社チ ノー内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masahiro Hiroraku 32-8, Kumano-cho, Itabashi-ku, Tokyo Chino Co., Ltd.

Claims (1)

【特許請求の範囲】[Claims] 【請求項１】 被測定体からの放射エネルギーを取り込
む検出窓の近くに配置され、前記放射エネルギーに重畳
するための予めレベル設定された基準光を断続的に出力
する基準光出力手段と、前記基準光の点灯時および消灯
時の放射エネルギーを検出する検出手段と、該検出手段
が検出した前記基準光の点灯時および消灯時の検出信号
のレベル差を演算する演算手段と、該演算手段が演算し
たレベル差を前記基準光のレベル値と一致するように補
正する補正手段とを備えたことを特徴とする光学的測定
装置。1. A reference light output means, which is arranged near a detection window for taking in radiant energy from an object to be measured, and which intermittently outputs a reference light whose level is set beforehand for superimposing on the radiant energy, and Detecting means for detecting radiant energy when the reference light is turned on and off, calculating means for calculating a level difference between detection signals detected by the detecting means when the reference light is turned on and turned off, and the calculating means An optical measuring device comprising: a correction unit that corrects the calculated level difference so as to match the level value of the reference light.