JPS6141933A - Method and device for measuring stress in body - Google Patents
Method and device for measuring stress in bodyInfo
- Publication number
- JPS6141933A JPS6141933A JP16358684A JP16358684A JPS6141933A JP S6141933 A JPS6141933 A JP S6141933A JP 16358684 A JP16358684 A JP 16358684A JP 16358684 A JP16358684 A JP 16358684A JP S6141933 A JPS6141933 A JP S6141933A
- Authority
- JP
- Japan
- Prior art keywords
- measured
- light
- stress
- optical path
- path difference
- 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.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims description 13
- 230000003287 optical effect Effects 0.000 claims abstract description 14
- 230000010287 polarization Effects 0.000 claims abstract description 7
- 238000005259 measurement Methods 0.000 abstract description 4
- 230000000694 effects Effects 0.000 abstract description 3
- 230000006378 damage Effects 0.000 abstract 2
- 230000035882 stress Effects 0.000 description 23
- 239000000835 fiber Substances 0.000 description 6
- 238000010586 diagram Methods 0.000 description 3
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 1
- 235000011613 Pinus brutia Nutrition 0.000 description 1
- 241000018646 Pinus brutia Species 0.000 description 1
- 241001474791 Proboscis Species 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/24—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet
- G01L1/241—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet by photoelastic stress analysis
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、物体内の応力分布を非破壊で測定する測定方
法および装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a measuring method and apparatus for non-destructively measuring stress distribution within an object.
従来、透明物体内の応力を測定する方法としては、光弾
性偏光器を用いる方法、すなわち、被測定物と１／４波
長板を、偏光子と検光子の間に挟み、物体内の主応力差
を透過光の光の強度に変換して測定する方法がある。Conventionally, the method of measuring stress within a transparent object is to use a photoelastic polarizer, in which the object to be measured and a quarter-wave plate are sandwiched between a polarizer and an analyzer, and the principal stress within the object is measured. There is a method of measuring the difference by converting it into the intensity of transmitted light.
〔発明がＷ６決しようとする問題点〕
上記のような従来の測定方法では、被測定物か平板状、
あるいは軸対称性を有している必要があり、軸対称でな
い３次元物体の場合には、被測定物を平板状１こ加工し
なければならず、被測定物を破壊してしまうという問題
があった。また、受光方法として写真撮影やフォトダイ
オードをスキャンする方法を用いているため、データの
解析や測定に時間がかかり、精度もあまりよくないとい
う問題もあった。[Problems that the invention attempts to resolve] In the conventional measurement method as described above, the object to be measured is flat,
Alternatively, it is necessary to have axial symmetry, and in the case of a three-dimensional object that is not axially symmetrical, the object to be measured must be machined into a flat plate, which may cause the problem of destroying the object. there were. Furthermore, since the method of receiving light involves taking photographs or scanning photodiodes, there are problems in that it takes time to analyze and measure data, and the accuracy is not very good.
本発明は、これら従来の問題を解決するものである。The present invention solves these conventional problems.
本発明の物体内の応力測定方法は、発光源から被測定物
Ｉζ光線を照射し、応力が物体に与える複屈折性によっ
て透過光に生じる直交する偏光間の光路差を、被測定物
を回転させながら受光装置で検出し、それらのデータに
基づいて、被測定物の断面内における該断面に垂直な応
力成分分布を求めることを特徴とす。The method for measuring stress in an object of the present invention involves irradiating the object to be measured with Iζ rays from a light source, and rotating the object to compensate for the optical path difference between orthogonal polarized lights that occurs in the transmitted light due to the birefringence that stress imparts to the object. The method is characterized in that the stress component distribution perpendicular to the cross section of the object to be measured is determined based on the data detected by the light receiving device while the object is being measured.
また、本発明の物体内の応力測定ｇｃ置は、レーザ光源
部、該レーザ光源の出力光を被測定物の大きさ以上の広
がりを有する平行光線に変換するレンズ系と、該平行光
線を直線偏光とするための偏亮子とによって光源部を構
成すると共に、被測定物の外周部屈折率と等しい屈折率
を有するマツチングオイルを充てんできかつ該被測定物
を所望の角度で回転できる回転台を備え、かつビディコ
ンと、該ビディコン上に被測定物の像を結像するレンズ
と、被測定物を通過したレーザ光を直線偏光とするため
のλ／４板と、偏光面のずれを検出するための検光子と
から受光部を構成し、さらにビディコンからの出力を処
理して所望の応力分布を求めるデータ処理部を備えて成
ることを特徴とする。The gc device for measuring stress in an object according to the present invention includes a laser light source section, a lens system that converts the output light of the laser light source into a parallel light beam having a spread larger than the size of the object to be measured, and a lens system that converts the parallel light beam into a straight line. A rotary table which constitutes a light source section with a polarizer for polarizing the light, is filled with matching oil having a refractive index equal to the refractive index of the outer circumference of the object to be measured, and is capable of rotating the object to be measured at a desired angle. and a vidicon, a lens for forming an image of the object to be measured on the vidicon, a λ/4 plate for linearly polarizing the laser beam that has passed through the object to be measured, and detecting a shift in the plane of polarization. The present invention is characterized in that the light receiving section is constituted by an analyzer for determining the amount of stress, and further includes a data processing section that processes the output from the vidicon to obtain a desired stress distribution.
以下、本発明を図面に基づいて説明する。 Hereinafter, the present invention will be explained based on the drawings.
第１図は本発明の測定装置の構成例を表わす。FIG. 1 shows an example of the configuration of a measuring device according to the present invention.
図中１はレーザ、２ａ、２ｂ、２ｃはレンズ、３は偏光
子、４は被測定物であり、レンズ２ａ 、 ２ｂは、レ
ーザ１の出力光を被測定物４の大きさ以上の広がりをも
つ平行光線に変換するレンズ系を成し、また偏光子３は
平行光線を直線偏光とするものである。これら、レーザ
１．レンズ２ａ、２ｂ１および偏光子３は光源部を構成
している。被測定物４は試料回転台５に固定されている
。この回転台５は、マツチングオイル６を充填でき、か
つ被測定物４を所望の角度回転できるものである。マツ
チングオイル６は、被測定物４の外周部の屈折率と等し
い屈折率を有する液体であり、光線が屈折によって曲が
ることを防ぐ。In the figure, 1 is a laser, 2a, 2b, and 2c are lenses, 3 is a polarizer, and 4 is an object to be measured. Lenses 2a and 2b spread the output light of the laser 1 to a size larger than the object to be measured 4. The polarizer 3 constitutes a lens system that converts the parallel light beams into parallel light beams, and the polarizer 3 converts the parallel light beams into linearly polarized light beams. These lasers 1. Lenses 2a, 2b1 and polarizer 3 constitute a light source section. The object to be measured 4 is fixed to a sample rotating table 5. This rotating table 5 can be filled with matching oil 6 and can rotate the object 4 to be measured at a desired angle. The matching oil 6 is a liquid having a refractive index equal to the refractive index of the outer periphery of the object to be measured 4, and prevents the light beam from being bent due to refraction.
また、７は１／４ Ｍ、長板、８は検光子％ ９はビデ
イコンであり、これらは前出したレンズ２ａと共に受光
部を構成している。レンズ２ａは、被測定物４の像をビ
デイコン９上に結像するように配置さｎている。１／４
波長板７は、被測定物４を通過したレーザ光を直線偏光
するものであり、また検光子８は、偏光面のずれを検出
するものである。Further, 7 is a 1/4 M long plate, 8 is an analyzer, and 9 is a videcon, which constitute a light receiving section together with the previously provided lens 2a. The lens 2 a is arranged so as to form an image of the object 4 on the videcon 9 . 1/4
The wavelength plate 7 linearly polarizes the laser beam that has passed through the object to be measured 4, and the analyzer 8 detects a shift in the plane of polarization.
また、１０は画像メモリ装置、１１は電子計算機、１２
は出力装置であり、これらはビデイコン９からの出力を
処理して所望の応力分布を求めるデータ処理部を成して
いる。Further, 10 is an image memory device, 11 is an electronic computer, and 12
is an output device, and these constitute a data processing section that processes the output from the videcon 9 to obtain a desired stress distribution.
次に、上記装置による応力の測定方法について説明する
。Next, a method for measuring stress using the above device will be explained.
まず、被ｄす宝物４を試料回転台５に固定し、その回転
角をある角度θ０に設定する。この状態において、偏光
子３により直線偏光となったレーザ１からのレーザ光を
被測定物４に入射する。この入射光は、物体内の応力分
布１こ起因する複屈折性により互いに直交する偏波面を
持つ２つの成分に分かれて、それぞれの成分が異った伝
播速度で進むため、物体を透過した光には光路差＆が生
じ、光線は清円偏波となる。光路差几は、光線の入射位
ｉｆＸと回転台の回転角θ０の関数から次式で与えられ
る。First, the treasure 4 to be d is fixed on the sample rotating table 5, and its rotation angle is set to a certain angle θ0. In this state, the laser beam from the laser 1, which has been linearly polarized by the polarizer 3, is incident on the object to be measured 4. This incident light is split into two components with mutually orthogonal polarization planes due to birefringence caused by the stress distribution within the object, and each component propagates at a different propagation speed, so the light that passes through the object An optical path difference & occurs, and the light beam becomes a clear circularly polarized wave. The optical path difference is given by the following equation from a function of the incident position ifX of the light beam and the rotation angle θ0 of the rotary table.
Ｒ（Ｘ、θ０）＝Ｃｆ″’ｒｚｄＹ −・・・・・
（１）ここで、Ｃは光弾性定数、Ｙは光層の進行方向
、σ２はＸ−Ｙ面に垂直な方向の物体内の応力であり、
被測定物４はＺ方向に一欣な形状および応力状をｑを有
するとしている（第２図）。この光路差を持つ光線が１
／４波長板７を通過すると、偏波面の角度が入射光の偏
光面よりΔφ＝πＢ、／λだけずれた直線偏光となる。R(X, θ0)=Cf″'rzdY −・・・・・
(1) Here, C is the photoelastic constant, Y is the traveling direction of the optical layer, and σ2 is the stress within the object in the direction perpendicular to the X-Y plane.
The object to be measured 4 is assumed to have a uniform shape and stress shape q in the Z direction (FIG. 2). A ray with this optical path difference is 1
When the light passes through the /4 wavelength plate 7, it becomes linearly polarized light whose polarization plane angle is shifted by Δφ=πB, /λ from the polarization plane of the incident light.
ただし、λは光の波長。However, λ is the wavelength of light.
そこで、検光子８の光軸１を回転させながらビディコン
９上の画像データを画像メモリ１０に読みとり、計算＋
Ｒ１１を用いて透過光の強度が最小となる検光子８の回
転角からΔφを求め、（１式の光路差ＩＩ、 （Ｘ 、
θ０）のデータをル＝Δφλ／πより求める。Therefore, while rotating the optical axis 1 of the analyzer 8, the image data on the vidicon 9 is read into the image memory 10, and the calculation +
Using R11, find Δφ from the rotation angle of the analyzer 8 where the intensity of the transmitted light is minimum, and (1 equation optical path difference II, (X,
The data of θ0) is obtained from Le=Δφλ/π.
次に、試料回転台５をある角度回転させて角度θ１とし
、上記と同じ操作によりＲ（Ｘ、θ１ ）のデータを得
る。この手順を試料回転台５が１回転するまで繰り返し
行なう。物体内の２方向の応力σ２はこのＩＬ （Ｘ
、θ０）ｔＲ（Ｘ、θＩＬ”’Ｒ（Ｘ、０ｎ）（ｎは任
意の数）のデータより次式を用いて計算機１１により計
算する。Next, the sample rotating table 5 is rotated by a certain angle to an angle θ1, and the data of R(X, θ1) is obtained by the same operation as above. This procedure is repeated until the sample rotating table 5 rotates once. The stress σ2 in two directions inside the object is this IL (X
, θ0) tR(X, θIL'''R(X, 0n) (n is an arbitrary number) using the following formula and calculated by the calculator 11.
ｄ曽〕ｄθ
Ｆ（ｗ−θ、ＷｓＩｒＩＯ）＝ｆ）Ｌ（Ｘ、θ）ｅｘｐ
（−ｉｗｘ）ｄＸｍ ３ （ａ）図は、実際に本装置を
用いて、応力付与形ｔｔｉｉｌ波保存元ファイバの一層
で断面形状が第３図中）のファイバ（通称・「ＰＡＮＬ
ＩＡファイバ」）１３のＴｌｆｒ面内の応力分布を測定
して、高さを応力の大きさとして３次元表示したもので
ある。このファイバ１３は、第３図（ｂ）中斜線で示し
た部分の熱膨張係数がその周囲に比べて大きくなるよう
に作られており、その斜線で示した部分で大きな熱応力
が生じるような構造となっている。その熱応力が第３
（ａ）図中の２つの山として表示されている。ファイバ
１３は、外径が１２５μｍ、１度と細く軸対称性もない
ためその２方向の応力を測定することは従来の方法では
極めて困難であった力ξ本発明の方法によれば簡単１こ
精度よく、かつ非破壊で測定することが可能となる。dso]dθ F(w-θ, WsIrIO)=f)L(X,θ)exp
(-iwx)dXm 3 (a) shows the fiber (commonly known as "PANL") (commonly known as "PANL"
The stress distribution in the Tlfr plane of the IA fiber (13) was measured, and the height was expressed three-dimensionally as the magnitude of stress. This fiber 13 is made in such a way that the coefficient of thermal expansion of the shaded area in FIG. It has a structure. The thermal stress is the third
(a) Displayed as two mountains in the figure. Since the fiber 13 has an outer diameter of 125 μm, is as thin as 1 degree, and has no axial symmetry, it is extremely difficult to measure the stress in two directions using conventional methods. It becomes possible to measure accurately and non-destructively.
なお、本実施例では、受光装置としてビディコン９２画
像メモリ１０を用いているため、透過光のデータを一度
に精度よく収集・記憶して、そのまま計算１機処理する
ことができ、応力測定の一層の高精度化、および、％連
化を図ることができる。In addition, in this example, since the Vidicon 92 image memory 10 is used as the light receiving device, transmitted light data can be collected and stored with high accuracy at one time, and calculations can be processed in one machine as it is, making stress measurement even easier. It is possible to achieve high accuracy and increase the percentage continuity.
以上説明したようｌこ、本発明によれば、被測定物を透
過してきた光に光弾性効果によって生じる光路差を、ｖ
ｌ、測定物を回転させながら測定して、ｖ！ｔｌＩＩｌ
ｌ定吻の断面内の応力分布・３求めるにめ、ある一つの
方間に一様な形状と応力分布をもつ物体の内部の応力分
布を、非破壊でかつ篇速に測定することができる。As explained above, according to the present invention, the optical path difference caused by the photoelastic effect in the light transmitted through the object to be measured is
l.Measure while rotating the object, v! tlIIl
In order to find the stress distribution within the cross section of a constant proboscis, the stress distribution inside an object that has a uniform shape and stress distribution in one direction can be measured non-destructively and quickly. .
第１図は本発明の応力測定装置の一例を表わす概略構成
図、り１２図は測定原理の幌、明図、２４３図（ａ）は
実測結果の一例を表わす図、第３図（ｂ）は被測定物と
したファイバの断面図である。
１・・・・・・レーザ（レーザ光源）、２ａ 、 ２ｂ
、 ２ｃ・・・・・・レンズ、３・・・・・・偏光子
、４・・・・・・被測定物、５・・・・・・試料回転台
、６・・・・・・マツチングオイル、７・・・・・・１
／４波長版、８・・・・・・検光子、９・・・・・・ビ
ディコン、１０・・・・・・画像メモリ、１１・・・・
・パ電子計カニ機、１２・・・・・・出力装置％ １３
・・・・・・ファイバ。
第１図
第２図Figure 1 is a schematic configuration diagram showing an example of the stress measuring device of the present invention, Figure 12 is a clear diagram of the measurement principle, Figure 243 (a) is a diagram showing an example of actual measurement results, and Figure 3 (b). is a cross-sectional view of a fiber used as an object to be measured. 1... Laser (laser light source), 2a, 2b
, 2c...lens, 3...polarizer, 4...object to be measured, 5...sample rotating table, 6...pine Ching oil, 7...1
/4 wavelength version, 8...analyzer, 9...vidicon, 10...image memory, 11...
・Paper electronic meter crab machine, 12...Output device% 13
······fiber. Figure 1 Figure 2
Claims (2)
に与える複屈折性によって透過光に生じる直交する偏光
間の光路差を、被測定物を回転させながら受光装置で検
出し、それらのデータに基づいて、被測定物の断面内に
おける該断面に垂直な応力成分分布を求めることを特徴
とする物体内の応力測定方法。(1) A light beam is irradiated from the light source to the object to be measured, and a light receiving device detects the optical path difference between orthogonal polarized lights that occurs in the transmitted light due to the birefringence that stress imparts to the object, while rotating the object to be measured, A method for measuring stress in an object, which comprises determining a stress component distribution perpendicular to a cross section of the object to be measured based on the data.
の大きさ以上の広がりを有する平行光線に変換するレン
ズ系と、該平行光線を直線偏光とするための偏光子とに
よって光源部を構成すると共に、被測定物の外周部屈折
率と等しい屈折率を有するマッチングオイルを充てんで
きかつ該被測定物を所望の角度で回転できる回転台を備
え、かつビディコンと、該ビディコン上に被測定物の像
を結像するレンズと、被測定物を通過したレーザ光を直
線偏光とするための１／４波長板と、偏光面のずれを検
出するための検光子とから受光部を構成し、さらにビデ
ィコンからの出力を処理して所望の応力分布を求めるデ
ータ処理部を備えて成ることを特徴とする物体内の応力
測定装置。(2) A light source unit consisting of a laser light source, a lens system that converts the output light of the laser light source into parallel light beams having a spread larger than the size of the object to be measured, and a polarizer that converts the parallel light beams into linearly polarized light. It comprises a vidicon and a rotary table which can be filled with matching oil having a refractive index equal to the refractive index of the outer circumference of the object to be measured and which can rotate the object to be measured at a desired angle. The light receiving section consists of a lens that forms an image of the object to be measured, a quarter-wave plate that linearly polarizes the laser beam that has passed through the object, and an analyzer that detects deviations in the plane of polarization. An apparatus for measuring stress in an object, further comprising a data processing section that processes the output from the vidicon to obtain a desired stress distribution.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16358684A JPS6141933A (en) | 1984-08-03 | 1984-08-03 | Method and device for measuring stress in body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16358684A JPS6141933A (en) | 1984-08-03 | 1984-08-03 | Method and device for measuring stress in body |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6141933A true JPS6141933A (en) | 1986-02-28 |
| JPH0369059B2 JPH0369059B2 (en) | 1991-10-30 |
Family
ID=15776728
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16358684A Granted JPS6141933A (en) | 1984-08-03 | 1984-08-03 | Method and device for measuring stress in body |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6141933A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6325341U (en) * | 1986-08-01 | 1988-02-19 | ||
| JP2007121174A (en) * | 2005-10-31 | 2007-05-17 | Univ Nagoya | Stress sensor |
| JP2009168813A (en) * | 2008-01-14 | 2009-07-30 | Gwangju Inst Of Science & Technology | Apparatus for measuring residual stress of optical fiber |
| WO2011065175A1 (en) * | 2009-11-27 | 2011-06-03 | 国立大学法人京都工芸繊維大学 | Stress measurement device and stress measurement method |
| CN103091014A (en) * | 2011-11-02 | 2013-05-08 | 财团法人工业技术研究院 | Optical measuring device |
| CN103115705A (en) * | 2013-01-19 | 2013-05-22 | 清华大学 | Stress and double refraction measurement instrument and measurement method based on cross-polarization solid laser |
-
1984
- 1984-08-03 JP JP16358684A patent/JPS6141933A/en active Granted
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6325341U (en) * | 1986-08-01 | 1988-02-19 | ||
| JP2007121174A (en) * | 2005-10-31 | 2007-05-17 | Univ Nagoya | Stress sensor |
| JP2009168813A (en) * | 2008-01-14 | 2009-07-30 | Gwangju Inst Of Science & Technology | Apparatus for measuring residual stress of optical fiber |
| WO2011065175A1 (en) * | 2009-11-27 | 2011-06-03 | 国立大学法人京都工芸繊維大学 | Stress measurement device and stress measurement method |
| CN103091014A (en) * | 2011-11-02 | 2013-05-08 | 财团法人工业技术研究院 | Optical measuring device |
| CN103115705A (en) * | 2013-01-19 | 2013-05-22 | 清华大学 | Stress and double refraction measurement instrument and measurement method based on cross-polarization solid laser |
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|---|---|
| JPH0369059B2 (en) | 1991-10-30 |
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