JPH0115005B2 - - Google Patents
Info
- Publication number
- JPH0115005B2 JPH0115005B2 JP3750583A JP3750583A JPH0115005B2 JP H0115005 B2 JPH0115005 B2 JP H0115005B2 JP 3750583 A JP3750583 A JP 3750583A JP 3750583 A JP3750583 A JP 3750583A JP H0115005 B2 JPH0115005 B2 JP H0115005B2
- Authority
- JP
- Japan
- Prior art keywords
- light
- optical
- transparent body
- light source
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 230000003287 optical effect Effects 0.000 claims description 38
- 239000013307 optical fiber Substances 0.000 claims description 15
- 230000005540 biological transmission Effects 0.000 claims description 14
- 239000004065 semiconductor Substances 0.000 claims description 11
- 238000009529 body temperature measurement Methods 0.000 claims description 6
- 230000001427 coherent effect Effects 0.000 claims description 3
- BJQHLKABXJIVAM-UHFFFAOYSA-N bis(2-ethylhexyl) phthalate Chemical compound CCCCC(CC)COC(=O)C1=CC=CC=C1C(=O)OCC(CC)CCCC BJQHLKABXJIVAM-UHFFFAOYSA-N 0.000 description 20
- 238000001514 detection method Methods 0.000 description 6
- 238000005259 measurement Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 239000010453 quartz Substances 0.000 description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 230000003595 spectral effect Effects 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000001228 spectrum Methods 0.000 description 3
- 238000005452 bending Methods 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000002730 additional effect Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000005674 electromagnetic induction Effects 0.000 description 1
- 238000000295 emission spectrum Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 238000001028 reflection method Methods 0.000 description 1
- VEALVRVVWBQVSL-UHFFFAOYSA-N strontium titanate Chemical compound [Sr+2].[O-][Ti]([O-])=O VEALVRVVWBQVSL-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K11/00—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00
- G01K11/12—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00 using changes in colour, translucency or reflectance
- G01K11/14—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00 using changes in colour, translucency or reflectance of inorganic materials
Description
【発明の詳細な説明】
本発明は光フアイバを用いた光応用温度計測装
置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical temperature measuring device using an optical fiber.
光技術を応用した各種の光応用計測装置は、従
来の電気式計測装置に比べて、耐電磁誘導障害特
性、防爆性等の利点を有し、最近の光伝送技術の
進歩に伴い、各種計測方式の提案が活発である。 Various optical measurement devices that apply optical technology have advantages over conventional electrical measurement devices, such as resistance to electromagnetic induction interference and explosion-proof properties. There are active proposals for methods.
この種の計測装置では、光フアイバの曲げによ
る伝送損失の変動や光コネクタの着脱による結合
損失の変動等を要因とする光伝送路特性の変動が
もたらす測定誤差を最小限に留める事が重要な技
術的課題である。 In this type of measurement equipment, it is important to minimize measurement errors caused by variations in optical transmission line characteristics, such as variations in transmission loss due to bending of optical fibers and variations in coupling loss due to attachment and detachment of optical connectors. This is a technical issue.
第１図は、従来用いられている光応用温度計測
装置における２波長反射方式の例を示すもので、
何らかの物理現象に基づく、トランスデユーサの
温度変化による反射光の強度変化を利用したもの
である。この装置は、前記光伝送路特性の変動を
補償するために波長の異る２つの光を用いるもの
であり、光源駆動回路１０１により光源（波長
λ1）１０２と光源（波長λ2）１０３を交互に駆動
する。光方向性結合器１０４により合波された光
は、一部ホトダイオード１０５により受光され、
光源出力変動モニタとして用いられる。光方向性
結合器１０６を経た光信号は、光フアイバ１０７
を介して温度検出部へ導かれる。温度検出部にお
いて、光フアイバ１０７から出射した光は、コリ
メータレンズ１０８により平行光となり、波長選
択透過性をもつダイクロイツクミラ１０９を透過
した光源１０２の出射光はトランスデユーサ１１
０へ入射し、温度変化により強度変調されて反射
される。一方、光源１０２とは波長の異る光源１
０３の出射光は、ダイクロイツクミラ１０９によ
り直接反射される。これらの反射光は、再びコリ
メータレンズ１０８により光フアイバ１０７端面
に集光され、光フアイバ１０７を逆方向に伝送し
て、光方向性結合器１０６を介してホトダイオー
ド１１１により受光される。受光後、AD変換器
１１２、マイクロコンピユータ１１３により２種
の光の強度比を演算すれば、光源１０３の出射光
は光伝送系の外乱のみをモニタしているので、光
伝送路特性の変動が補償される。 Figure 1 shows an example of a two-wavelength reflection method in a conventional optical temperature measurement device.
This is based on some physical phenomenon and utilizes changes in the intensity of reflected light due to changes in the temperature of the transducer. This device uses two lights of different wavelengths to compensate for the fluctuations in the optical transmission path characteristics, and a light source (wavelength λ 1 ) 102 and a light source (wavelength λ 2 ) 103 are controlled by a light source drive circuit 101. Drive alternately. A portion of the light multiplexed by the optical directional coupler 104 is received by the photodiode 105,
Used as a light source output fluctuation monitor. The optical signal that has passed through the optical directional coupler 106 is transferred to an optical fiber 107.
is guided to the temperature detection section via. In the temperature detection section, the light emitted from the optical fiber 107 is turned into parallel light by the collimator lens 108, and the light emitted from the light source 102, which has passed through the dichroic mirror 109 having wavelength selective transparency, is transmitted to the transducer 11.
0, the intensity is modulated by temperature changes, and reflected. On the other hand, the light source 1 having a different wavelength from the light source 102
The emitted light 03 is directly reflected by the dichroic mirror 109. These reflected lights are again focused on the end face of the optical fiber 107 by the collimator lens 108, transmitted in the opposite direction through the optical fiber 107, and received by the photodiode 111 via the optical directional coupler 106. After receiving the light, the AD converter 112 and the microcomputer 113 calculate the intensity ratio of the two types of light, and the light emitted from the light source 103 monitors only the disturbance in the optical transmission system, so it is possible to detect fluctuations in the optical transmission path characteristics. be compensated.
上記２波長反射方式温度計測装置においては、
ダイクロイツクミラの分光特性の制約上、用いる
２つの波長を少くとも100nm程度分離しておく必
要があるが、光伝送系の変動要因は光フアイバに
対する曲げ・内部応力、あるいは光コネクタ着脱
時の位置ズレ、光コネクタ・光方向性結合器等の
光学要素の突き合せ面における多波干渉効果等複
雑多岐にわたつており、上記諸変動要因が異る波
長の光に対して等価に作用するという保障はな
い。また、上記ダイクロツクミラは温度検出部に
おいてトランスデユーサと隣接して配置されるべ
きものであり、測定温度の変化によりその分光特
性も変化することが考えられ、新たな誤差の原因
となる。 In the above two-wavelength reflection type temperature measurement device,
Due to restrictions on the spectral characteristics of dichroic mirrors, it is necessary to separate the two wavelengths used by at least 100 nm, but the fluctuation factors in the optical transmission system are bending and internal stress on the optical fiber, or the position when connecting and disconnecting the optical connector. Misalignment, multi-wave interference effects at the butting surfaces of optical elements such as optical connectors and optical directional couplers, etc. are complex and diverse, and there is no guarantee that the above-mentioned fluctuation factors act equally on light of different wavelengths. There isn't. Further, the dichroic mirror should be placed adjacent to the transducer in the temperature detecting section, and its spectral characteristics may change as the measured temperature changes, causing a new error.
この発明は、上述の欠点を除去して、より高精
度な光伝送路変動補償効果を備えた光応用温度計
測装置を提供することを目的とする。 SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks and provide an optical temperature measuring device that has a more accurate optical transmission path fluctuation compensation effect.
本発明では、温度変化を光量変化に変換するト
ランスデユーサとして、所定の反射率を有する平
坦で平行な端面をもつ光学的透明体（エタロン）
を用いる。第２図において、所定の屈折率ｎ、厚
みｌおよび表面反射率ｒを持つエタロン２０１の
端面に垂直に光を入射する場合、光の干渉により
エタロン２０１の反射率Ｒは、
Ｒ＝∫∞ 0ρ（λ）4rsin2（2πnl／λ）／（１−ｒ）2
＋4rsin2（2πnl／λ）dλ
で与えられる。但しλは波長、ρ（λ）は入射光
のスペクトルである。一般にエタロン材料の屈折
率ｎと厚みｌは温度によつて変化するため、エタ
ロンの反射率Ｒも温度の関数となる。 In the present invention, an optical transparent body (etalon) having a flat and parallel end face having a predetermined reflectance is used as a transducer that converts temperature changes into light intensity changes.
Use. In FIG. 2, when light is incident perpendicularly to the end face of the etalon 201 having a predetermined refractive index n, thickness l, and surface reflectance r, the reflectance R of the etalon 201 due to light interference is as follows: R=∫ ∞ 0 ρ(λ)4rsin 2 (2πnl/λ)/(1-r) 2
It is given by +4rsin 2 (2πnl/λ)dλ. However, λ is the wavelength and ρ(λ) is the spectrum of the incident light. Generally, the refractive index n and thickness l of an etalon material change with temperature, so the reflectance R of the etalon is also a function of temperature.
光源として第３図に示す様な隣接した数本の線
スペクトルを持つマルチモード半導体レーザ光を
用いる場合、厚さ約20μｍの石英エタロンでは温
度変化（nl積の変化）によつて反射率は第４図の
様に周期的に変化する。図は計算結果で表面反射
率ｒをパラメータとする。従つて、特定の温度範
囲では温度と反射率が１対１に対応し、温度の計
測が可能であり、測定温度範囲もエタロンの厚み
を最適化することにより制御が可能である。 When using a multimode semiconductor laser beam with a spectrum of several adjacent lines as shown in Figure 3 as a light source, the reflectance of a quartz etalon with a thickness of about 20 μm changes due to temperature changes (changes in the nl product). It changes periodically as shown in Figure 4. The figure shows the calculation results using the surface reflectance r as a parameter. Therefore, in a specific temperature range, there is a one-to-one correspondence between temperature and reflectance, and temperature can be measured, and the measurement temperature range can also be controlled by optimizing the thickness of the etalon.
次に、このエタロンに第５図に示す様なガウス
型スペクトル分布ρ（λ）
（但しλ0は中心波長、ρはスペクトルの拡がりを
示すパラメータ）を持つ発光ダイオード（LED）
光を入射した場合のエタロン反射率の温度変化の
計算結果を第６図に示す。LED光はインコヒー
レントであるため20μｍ程度のエタロンにおいて
は殆ど干渉を起こさず、表面反射率ｒを適当に選
べばエタロンの温度変化の影響を受けない。従つ
て、トランスデユーサによる強度変化を受けず、
光伝送路特性の変動のみをモニタする参照光とし
て、LEDを用いれば良いことがわかる。 Next, this etalon is given a Gaussian spectral distribution ρ(λ) as shown in Figure 5. (where λ 0 is the center wavelength and ρ is a parameter indicating the spectrum spread)
FIG. 6 shows calculation results of temperature changes in etalon reflectance when light is incident. Since LED light is incoherent, there is almost no interference in an etalon of about 20 μm, and if the surface reflectance r is appropriately selected, it will not be affected by changes in etalon temperature. Therefore, it is not affected by the intensity change due to the transducer,
It can be seen that it is sufficient to use an LED as a reference light for monitoring only changes in optical transmission path characteristics.
第７図はこの発明の実施例を示すもので、エタ
ロンの温度変化による強度変調を受けるコヒーレ
ントな信号光として半導体レーザ光を用い、光伝
送路特性の変動をモニタするインコヒーレントな
参照光としてLED光を用いる。半導体レーザに
関しては、マルチモードフアイバを使用する場合
はモーダルノイズの点からマルチモードレーザが
適する。シングルモードレーザを使用するとき
は、同様の理由によりシングルモードフアイバが
適する。 FIG. 7 shows an embodiment of the present invention, in which a semiconductor laser beam is used as a coherent signal beam that undergoes intensity modulation due to temperature changes in the etalon, and an LED is used as an incoherent reference beam to monitor fluctuations in optical transmission path characteristics. Use light. Regarding semiconductor lasers, when using a multimode fiber, a multimode laser is suitable from the viewpoint of modal noise. When using a single mode laser, a single mode fiber is suitable for similar reasons.
光源駆動回路７０１により、半導体レーザ７０
２とLED７０３を交互に駆動する。光方向性結
合器７０４により合成された２種の光は、一部ホ
トダイオード７０５により受光され、光源出力変
動モニタとして用いられる。光方向性結合器７０
６を経た光信号は、光フアイバ７０７を経て温度
検出部へ伝送される。温度検出部において、光フ
アイバ７０７から出射した光は、コリメータレン
ズ７０８により平行光となり、エタロン７１０へ
入射する。エタロンは石英またはチタン酸ストロ
ンチウム等の耐熱性光学結晶により、その屈折率
の温度係数、熱膨張係数を考慮して測定温度範囲
に応じて適当な厚さに形成されており、端面には
適当な表面反射率ｒを与える反射コーテイングが
施されている。石英エタロンに信号光としてマル
チモード半導体レーザ、参照光としてLEDを用
いる場合、前記第４図および第６図の計算結果か
ら、両光の干渉状態を考慮して、ｒ＝0.3〜0.4が
適当である。但しこの最適値は、エタロンの厚み
により多少変化する。エタロン７０１からの反射
光は、再びコリメータレンズ７０８により光フア
イバ７０７端面に集光され、光フアイバ７０７を
逆方向に伝送し、光方向性結合器７０６を介して
ホトダイオード７１１により受光される。ホトダ
イオード７１１により受光される半導体レーザ光
とLED光の強度をそれぞれS1，S2とし、ホトダ
イオード７０５により受光される半導体レーザ光
とLED光の強度をそれぞれR1，R2とすると、AD
変換器７１２、マイクロコンピユータ７１３によ
り
Ｘ（Ｔ）＝S1／R1／S2／R2
の演算を行えば、光伝送路特性の変動並びに光源
出力の変動が補償された温度情報Ｘ（Ｔ）が得ら
れる。 The light source drive circuit 701 drives the semiconductor laser 70
2 and LED 703 are driven alternately. A portion of the two types of light combined by the optical directional coupler 704 is received by a photodiode 705 and used as a light source output fluctuation monitor. Optical directional coupler 70
The optical signal that has passed through the optical fiber 707 is transmitted to the temperature detection section. In the temperature detection section, the light emitted from the optical fiber 707 is turned into parallel light by the collimator lens 708 and enters the etalon 710. The etalon is made of heat-resistant optical crystal such as quartz or strontium titanate, and is formed to have an appropriate thickness depending on the measurement temperature range, taking into consideration the temperature coefficient of its refractive index and coefficient of thermal expansion. A reflective coating is applied giving a surface reflectance r. When using a multi-mode semiconductor laser as a signal light and an LED as a reference light in a quartz etalon, from the calculation results shown in Figures 4 and 6 above, taking into account the state of interference between both lights, r = 0.3 to 0.4 is appropriate. be. However, this optimum value changes somewhat depending on the thickness of the etalon. The reflected light from the etalon 701 is again focused on the end face of the optical fiber 707 by the collimator lens 708, transmitted in the opposite direction through the optical fiber 707, and received by the photodiode 711 via the optical directional coupler 706. If the intensities of the semiconductor laser light and LED light received by the photodiode 711 are S 1 and S 2 , respectively, and the intensities of the semiconductor laser light and LED light received by the photodiode 705 are R 1 and R 2 , respectively, AD
When the converter 712 and the microcomputer 713 calculate X(T)=S 1 /R 1 /S 2 /R 2 , temperature information X(T ) is obtained.
この発明は、２種の光のコヒーレンシの差を利
用したものであるため、信号光と伝送路参照光と
で同一の中心波長の光を用いることが可能であ
り、異なる波長の光を用いる従来の２波長方式に
比べて、伝送路分散による補償誤差がない。 Since this invention utilizes the difference in coherency between two types of light, it is possible to use light with the same center wavelength for the signal light and the transmission line reference light, which is different from the conventional method of using light of different wavelengths. Compared to the two-wavelength method, there is no compensation error due to transmission line dispersion.
また、ダイクロイツクミラが不要であるため、
この分光特性の温度変化による補償誤差もなく、
補償効果の改善が図れ、構成も簡単になる。さら
に、実施例で述べた方式の反射光を検出する反射
型だけでなく透過型の検出部構成も可能であると
いう付加的な効果も得られる。 In addition, since dikreutzukumira is not required,
There is no compensation error due to temperature changes in this spectral characteristic.
The compensation effect can be improved and the configuration can be simplified. Furthermore, an additional effect can be obtained in that it is possible to configure not only a reflective type detection unit for detecting reflected light as described in the embodiment, but also a transmission type detection unit configuration.
第１図は従来用いられている２波長反射方式光
応用温度計測装置を例示する接続図、第２図は本
発明の装置において使用されるエタロンの構成を
例示する側面図、第３図および第５図は本発明の
装置において使用されるマルチモード半導体レー
ザおよびLEDの典型的な発光スペクトル図、第
４図および第６図は本発明の装置において使用さ
れる石英エタロンにおけるマルチモード半導体レ
ーザおよびLEDの干渉の程度を例示した計算結
果を示す線図、第７図は本発明の実施例を示す接
続図である。
１０１：光源駆動回路、１０２：光源、１０
３：光源、１０４：光方向性結合器、１０
５：ホトダイオード、１０６：光方向性結合器
、１０７：光フアイバ、１０８：コリメータレ
ンズ、１０９：ダイクロイツクミラ、１１０：ト
ランスデユーサ、１１１：ホトダイオード、１
１２：AD変換器、１１３：マイクロコンピユー
タ、７０１：光源駆動回路、７０２：半導体レー
ザ、７０３：LED、７０４：光方向性結合器、
７０５：ホトダイオード、７０６：光方向性結
合器、７０７：光フアイバ、７０８：コリメー
タレンズ、７１０：エタロン、７１１：ホトダイ
オード、７１２：AD変換器、７１３：マイク
ロコンピユータ。
FIG. 1 is a connection diagram illustrating a conventional two-wavelength reflection type optical temperature measurement device, FIG. 2 is a side view illustrating the configuration of an etalon used in the device of the present invention, and FIGS. Figure 5 is a typical emission spectrum diagram of a multimode semiconductor laser and LED used in the device of the present invention, and Figures 4 and 6 are diagrams of a multimode semiconductor laser and LED in a quartz etalon used in the device of the present invention. FIG. 7 is a diagram showing calculation results illustrating the degree of interference in FIG. 7, and FIG. 7 is a connection diagram showing an embodiment of the present invention. 101: Light source drive circuit, 102: Light source, 10
3: light source, 104: optical directional coupler, 10
5: Photodiode, 106: Optical directional coupler, 107: Optical fiber, 108: Collimator lens, 109: Dichroic mirror, 110: Transducer, 111: Photodiode, 1
12: AD converter, 113: Microcomputer, 701: Light source drive circuit, 702: Semiconductor laser, 703: LED, 704: Optical directional coupler,
705: Photodiode, 706: Optical directional coupler, 707: Optical fiber, 708: Collimator lens, 710: Etalon, 711: Photodiode, 712: AD converter, 713: Microcomputer.
Claims (1)
つ光学的透明体と、光源と、前記透明体に前記光
源の光を伝送し、前記透明体からの反射光または
透過光を伝送する光フアイバと、この反射光また
は透過光を受ける受光部と、電気信号処理部とを
備え、前記透明体内部における光の干渉状態の温
度変化による前記透明体の反射光強度または透過
光強度の変化を利用した光応用温度計測装置にお
いて、前記透明体内部で干渉し得るコヒーレント
な光と、前記透明体内部で干渉し得ないインコヒ
ーレントな光との二種の光源を用い、受光後に前
記二種の光の強度比を演算することにより光フア
イバ等の光伝送路の特性変動を補償することを特
徴とする光応用温度計測装置。 ２ 特許請求の範囲第１項記載の光応用温度計測
装置において、コヒーレントな光源としてマルチ
モード半導体レーザを用いることを特徴とする光
応用温度計測装置。[Scope of Claims] 1. An optical transparent body having flat and parallel end faces having a predetermined reflectance, a light source, transmitting light from the light source to the transparent body, and transmitting light reflected or transmitted from the transparent body. It includes an optical fiber that transmits light, a light receiving section that receives the reflected light or the transmitted light, and an electrical signal processing section, and the intensity or transmission of the reflected light of the transparent body is determined by the temperature change of the light interference state inside the transparent body. In an optical temperature measurement device that utilizes changes in light intensity, two types of light sources are used: coherent light that can interfere inside the transparent body, and incoherent light that cannot interfere inside the transparent body, and receives light. An optical temperature measurement device characterized in that the temperature measurement device compensates for characteristic fluctuations of an optical transmission line such as an optical fiber by later calculating the intensity ratio of the two types of light. 2. An optical temperature measuring device according to claim 1, characterized in that a multimode semiconductor laser is used as a coherent light source.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3750583A JPS59163529A (en) | 1983-03-09 | 1983-03-09 | Light-applied temperature measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3750583A JPS59163529A (en) | 1983-03-09 | 1983-03-09 | Light-applied temperature measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59163529A JPS59163529A (en) | 1984-09-14 |
| JPH0115005B2 true JPH0115005B2 (en) | 1989-03-15 |
Family
ID=12499381
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3750583A Granted JPS59163529A (en) | 1983-03-09 | 1983-03-09 | Light-applied temperature measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59163529A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006517028A (en) * | 2003-01-16 | 2006-07-13 | メディツィニシェス ラザーツェントラム リューベック ゲゼルシャフト ミット ベシュレンクテル ハフツング | Non-contact temperature monitor and control method and apparatus |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6486999B1 (en) * | 2000-03-15 | 2002-11-26 | Agere Systems Inc. | Using crystalline materials to control the thermo-optic behavior of an optical path |
-
1983
- 1983-03-09 JP JP3750583A patent/JPS59163529A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006517028A (en) * | 2003-01-16 | 2006-07-13 | メディツィニシェス ラザーツェントラム リューベック ゲゼルシャフト ミット ベシュレンクテル ハフツング | Non-contact temperature monitor and control method and apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59163529A (en) | 1984-09-14 |
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