JPH0526630A - Displacement measuring device - Google Patents
Displacement measuring deviceInfo
- Publication number
- JPH0526630A JPH0526630A JP20761591A JP20761591A JPH0526630A JP H0526630 A JPH0526630 A JP H0526630A JP 20761591 A JP20761591 A JP 20761591A JP 20761591 A JP20761591 A JP 20761591A JP H0526630 A JPH0526630 A JP H0526630A
- Authority
- JP
- Japan
- Prior art keywords
- grating
- light
- gain medium
- measured
- measuring device
- 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
Landscapes
- Length Measuring Devices By Optical Means (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、構造物内部歪の検出に
適用される変位測定装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a displacement measuring device applied to detect internal strain of a structure.
【０００２】[0002]
【従来の技術】従来の変位測定装置の一例を図２模式図
に示すと、これは、被測定物２１の一端にミラー２２を
取付けておき、光源２７より出た光をハーフミラー２４
により２本に分離しミラー２２及び固定ミラー２３に入
射させ、それぞれの反射光を再びハーフミラー２４を介
して合流させレンズ２５によりスクリーン２６上に干渉
じまを生じさせるマイケルソン干渉計を基本構造として
持つものである。しかして、被測定物２１の長さの変化
によりそこに固定したミラー２２からハーフミラー２４
までの距離が変化し、ミラー２２及び固定ミラー２３か
らの反射光のスクリーン２６上での位相差が変化し干渉
じまの位置が変化する。この変化量を測定することによ
り光の波長オーダー（数１００ｎｍ）以下の高精度の変
位検出が可能となる。2. Description of the Related Art An example of a conventional displacement measuring device is shown in the schematic view of FIG. 2, in which a mirror 22 is attached to one end of an object to be measured 21 and light emitted from a light source 27 is reflected by a half mirror 24.
The Michelson interferometer is a basic structure in which the light is split into two by the laser light and is incident on the mirror 22 and the fixed mirror 23, and the respective reflected lights are merged again through the half mirror 24 to cause interference fringes on the screen 26 by the lens 25. Have as. Then, due to the change in the length of the DUT 21, the mirror 22 fixed to the half mirror 24
Changes, the phase difference of the reflected light from the mirror 22 and the fixed mirror 23 on the screen 26 changes, and the position of the interference stripe changes. By measuring this amount of change, it is possible to detect the displacement with high accuracy on the order of the wavelength of light (several hundreds of nm) or less.
【０００３】しかしながらこのような装置では、被測定
物の内部で生じた歪の総量としての全長の変化しか検出
できないとともに、干渉計を安定に設置する必要があ
り、橋りょう，高層建造物等一般的な環境での使用が困
難である。However, such an apparatus can detect only the change in the total length as the total amount of strain generated inside the object to be measured, and it is necessary to stably install the interferometer, which is generally used for bridges, high-rise buildings and the like. It is difficult to use in various environments.
【０００４】[0004]
【発明が解決しようとする課題】本発明は、このような
事情に鑑みて提案されたもので、被測定物の局部的な歪
による変位を簡便かつ正確に検出することができる変位
測定装置を提供することを目的とする。SUMMARY OF THE INVENTION The present invention has been proposed in view of the above circumstances, and provides a displacement measuring device capable of simply and accurately detecting the displacement of a measured object due to local strain. The purpose is to provide.
【０００５】[0005]
【課題を解決するための手段】そのために本発明は、被
測定物の表面に透明のバッファー層を介して光の導波層
を設け、同導波層の一部に励起光を受ける利得媒質部を
形成するとともに、同利得媒質部の一方の側に格子間隔
一定の第１グレーティング、他方の側に格子間隔が上記
第１グレーティングのそれの２倍を含み連続的に変化す
る第２グレーティングをそれぞれ形成したことを特徴と
する。To this end, the present invention provides a gain medium in which an optical waveguide layer is provided on the surface of an object to be measured through a transparent buffer layer, and a portion of the waveguide layer receives pumping light. Part of the same gain medium portion, a first grating having a constant lattice spacing is provided on one side of the gain medium portion, and a second grating having a lattice spacing continuously changing including twice that of the first grating is provided on the other side. It is characterized in that each is formed.
【０００６】[0006]
【作用】上述の構成により、被測定物の局部的な歪によ
る変位を簡便かつ正確に検出することができる変位測定
装置を得ることができる。With the above structure, it is possible to obtain a displacement measuring device capable of simply and accurately detecting the displacement of the object to be measured due to local strain.
【０００７】[0007]
【実施例】本発明変位測定装置の一実施例を図１断面図
について説明すると、被測定物１１の表面に、 SiO2や
ＰＭＭＡ（ポリメタクリレート）などの透明のバッファ
ー層１２を介してそれより屈折率の高い導波層１３を設
け、光導波路を形成する。この導波層１３としてはガラ
スや透明な樹脂を用いる。しかしてこの導波層１３の一
部に、励起光ＬP を受ける部分として、利得媒質として
レーザー色素やNd ,Erなどの原子を含む利得媒質部１３
0 を形成する。更にこの利得媒質部１３0 の両側に、一
定の格子間隔Λ1 の第１グレーティング１３1 と、Λ1
の２倍を含み位置によってなだらかに連続して変化する
格子間隔Λ2(ｘ) を有する第２グレーティング１３2 を
形成する。EXAMPLES To illustrate an embodiment of the present invention displacement measuring apparatus 1 a cross-sectional view for, on the surface of the object 11, than through the SiO 2 and PMMA (polymethyl methacrylate) transparent buffer layer 12, such as The waveguide layer 13 having a high refractive index is provided to form an optical waveguide. Glass or transparent resin is used as the waveguide layer 13. As a gain medium, a portion of the waveguide layer 13 that receives the pumping light L P includes a gain medium portion 13 that includes a laser dye and atoms such as Nd and Er.
Form 0 . Further on either side of the gain medium 13 0, the first grating 13 1 having a constant grating spacing lambda 1, lambda 1
To form a second grating 13 2 having a lattice spacing Λ 2 (x) which is twice as large as and which continuously changes depending on the position.
【０００８】このような装置において、利得媒質部１３
0 を励起光ＬP によって励起することによって利得媒質
からある波長範囲の光を持つ蛍光が生ずる。その内の波
長λ0 に対してグレーティング格子間隔Λを導波路中の
光波の位相定数βを用いてΛ＝ｑπ／βの関係を満たす
ようにすれば、グレーティングは反射器としての特性を
示す。ただしｑは整数である。In such a device, the gain medium section 13
By exciting 0 with the pumping light L P , fluorescence having light in a certain wavelength range is generated from the gain medium. If the grating lattice spacing Λ for the wavelength λ 0 among them is set to satisfy the relation of Λ = qπ / β by using the phase constant β of the light wave in the waveguide, the grating exhibits characteristics as a reflector. However, q is an integer.
【０００９】そしてΛ1 はｑ＝１とした場合であり、Λ
2 はある位置ｘ0 においてΛ2(ｘ0 ) ＝２Λ1 を持ち連
続的に格子間隔がゆるやかに変化するように選んであ
る。ｑ＝２の場合においては２次の回折波が反射波とな
り１次の回折波は導波層表面の法線方向に生ずる。すな
わち波長λ0 の光が第１グレーティング１３1 と第２グ
レーティング１３2 のΛ2 ＝２Λ1 となる領域との間で
くり返し反射されることにより増幅されレーザー発振を
生じ、第２グレーティング１３2 の１次回折波によって
波長λ0 のレーザー出力Ｌ0 が出力される面発光レーザ
ーとなる。Λ 1 is the case where q = 1, and Λ
2 has Λ 2 (x 0 ) = 2Λ 1 at a certain position x 0 , and is selected so that the lattice spacing changes continuously and gradually. When q = 2, the second-order diffracted wave becomes a reflected wave and the first-order diffracted wave is generated in the direction normal to the surface of the waveguide layer. That is, the light of the wavelength λ 0 is repeatedly reflected between the region of Λ 2 = 2Λ 1 of the first grating 13 1 and the second grating 13 2 to be amplified and generate laser oscillation, and the second grating 13 2 The surface emitting laser outputs a laser output L 0 having a wavelength λ 0 by the first-order diffracted wave.
【００１０】次に被測定物１１が内部歪により変形し表
面の長さが変化した場合について考える。長さの変化量
が第１グレーティング１３1 の格子間隔Λ1 に対してδ
である（Λ1′＝Λ1 ＋δ）とすると、第２グレーティ
ング１３2 のｘ0 における格子間隔Λ2′(x0 ) はΛ
2(ｘ0)＋δ＝２（Λ1 ＋δ/2）となり、Λ2′( ｘ0)＝
２Λ1′の関係が満たされなくなる。しかし第２グレー
ティング１３2 の格子間隔は連続的に変化しているた
め、Λ2′(ｘ）＝２Λ1′が成り立つ位置ｘが存在し、
Λ1′に対応する波長λ′のレーザー光が出力される。
かくして被測定物１１の変位は連続的な波長の変化とし
て検出される。Next, consider a case where the object 11 to be measured is deformed by internal strain and the surface length is changed. The amount of change in length is δ for the lattice spacing Λ 1 of the first grating 13 1.
(Λ 1 ′ = Λ 1 + δ), the lattice spacing Λ 2 ′ (x 0 ) of the second grating 13 2 at x 0 is Λ
2 (x 0 ) + δ = 2 (Λ 1 + δ / 2), and Λ 2 ′ (x 0 ) =
The relation of 2Λ 1 ′ cannot be satisfied. However, since the lattice spacing of the second grating 13 2 is continuously changing, there is a position x where Λ 2 ′ (x) = 2Λ 1 ′ holds,
Laser light of wavelength λ'corresponding to Λ 1 'is output.
Thus, the displacement of the DUT 11 is detected as a continuous wavelength change.
【００１１】以上説明したように、このような装置によ
れば、被測定物１１の表面に面発光分布反射型波長可変
レーザーをバッファー層１２を介して形成することによ
って、内部歪によって生じた表面の変位を波長の変化と
して検出できる。またこの装置は光のみで動作させるこ
とが可能であり、励起光ＬP としてパルス幅が数ｎｓ以
下の短光パルスを用いれば励動などによる変動を受けな
い安定な検出ができる。更に面発光レーザーであるため
出力光が直接外部に取り出せることから非接触計測が可
能である。As described above, according to such an apparatus, the surface emission distributed reflection type wavelength tunable laser is formed on the surface of the DUT 11 through the buffer layer 12, so that the surface generated by the internal strain is generated. Can be detected as a change in wavelength. Further, this device can be operated only by light, and if a short optical pulse having a pulse width of several ns or less is used as the excitation light L P , stable detection can be performed without fluctuation due to excitation or the like. Furthermore, since it is a surface emitting laser, the output light can be directly extracted to the outside, so non-contact measurement is possible.
【００１２】[0012]
【発明の効果】要するに本発明によれば、被測定物の表
面に透明のバッファー層を介して光の導波層を設け、同
導波層の一部に励起光を受ける利得媒質部を形成すると
ともに、同利得媒質部の一方の側に格子間隔一定の第１
グレーティング、他方の側に格子間隔が上記第１グレー
ティングのそれの２倍を含み連続的に変化する第２グレ
ーティングをそれぞれ形成したことにより、被測定物の
局部的な歪による変位を簡便かつ正確に検出することが
できる変位測定装置を得るから、本発明は産業上極めて
有益なものである。In summary, according to the present invention, an optical waveguide layer is provided on the surface of the object to be measured through a transparent buffer layer, and a gain medium portion for receiving pump light is formed in a part of the waveguide layer. In addition, a first grating with a constant lattice spacing is provided on one side of the gain medium section.
By forming a grating and a second grating, on the other side of which the grating spacing continuously changes, including twice that of the first grating, the displacement due to local strain of the measured object can be easily and accurately obtained. The present invention is extremely useful industrially because a displacement measuring device capable of detecting is obtained.
【図１】本発明変位測定装置の一実施例の断面図であ
る。FIG. 1 is a sectional view of an embodiment of a displacement measuring device of the present invention.
【図２】従来の変位測定装置の模式図である。FIG. 2 is a schematic diagram of a conventional displacement measuring device.
11 被測定物 12 バッファー層 13 導波層 130 利得媒質部 131 第１グレーティング 132 第２グレーティング11 DUT 12 Buffer layer 13 Waveguide layer 13 0 Gain medium part 13 1 First grating 13 2 Second grating
Claims (1)
介して光の導波層を設け、同導波層の一部に励起光を受
ける利得媒質部を形成するとともに、同利得媒質部の一
方の側に格子間隔一定の第１グレーティング、他方の側
に格子間隔が上記第１グレーティングのそれの２倍を含
み連続的に変化する第２グレーティングをそれぞれ形成
したことを特徴とする変位測定装置。Claim: What is claimed is: 1. A waveguide layer for light is provided on the surface of an object to be measured through a transparent buffer layer, and a gain medium portion for receiving pump light is formed in a part of the waveguide layer. At the same time, a first grating having a constant lattice spacing is formed on one side of the same gain medium portion, and a second grating having a lattice spacing continuously changing including twice that of the first grating is formed on the other side. Displacement measuring device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20761591A JP2915636B2 (en) | 1991-07-24 | 1991-07-24 | Displacement measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20761591A JP2915636B2 (en) | 1991-07-24 | 1991-07-24 | Displacement measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0526630A true JPH0526630A (en) | 1993-02-02 |
| JP2915636B2 JP2915636B2 (en) | 1999-07-05 |
Family
ID=16542727
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20761591A Expired - Lifetime JP2915636B2 (en) | 1991-07-24 | 1991-07-24 | Displacement measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2915636B2 (en) |
-
1991
- 1991-07-24 JP JP20761591A patent/JP2915636B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JP2915636B2 (en) | 1999-07-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6549687B1 (en) | System and method for measuring physical, chemical and biological stimuli using vertical cavity surface emitting lasers with integrated tuner | |
| US6836578B2 (en) | System and method for measuring physical stimuli using vertical cavity surface emitting lasers with integrated tuning means | |
| US5677769A (en) | Optical sensor utilizing rare-earth-doped integrated-optic lasers | |
| US5341205A (en) | Method for characterization of optical waveguide devices using partial coherence interferometry | |
| US6643025B2 (en) | Microinterferometer for distance measurements | |
| EP0023345A2 (en) | Optical sensing system | |
| JP4892401B2 (en) | Optical interference measurement device | |
| TW201719109A (en) | Apparatus for measuring cavity length of optical resonant cavity | |
| US7308162B2 (en) | Intrinsic Fabry-Perot optical fiber sensors and their multiplexing | |
| CN112304213B (en) | Fabry-Perot grating interferometer for single-degree-of-freedom displacement measurement and measurement method thereof | |
| US20030046024A1 (en) | Apparatus and method for volumetric dilatometry | |
| JP2915636B2 (en) | Displacement measuring device | |
| JP4027352B2 (en) | Optical fiber probe device | |
| Imran et al. | Measurement of the group-delay dispersion of femtosecond optics using white-light interferometry | |
| EP1690254B1 (en) | Measurement device | |
| JPH06241929A (en) | Optical fiber sensor | |
| RU2082119C1 (en) | Fiber-optical multiplexer which measures temperature | |
| RU2084845C1 (en) | Fibre-interference system of pressure measurement | |
| JP2934535B2 (en) | Waveguide type tunable ring laser | |
| Qu et al. | Micro-displacement sensors based on plastic photonic bandgap bragg fibers | |
| Chen et al. | Fiber-optic Fabry-Perot Interferometry for High-resolution Motion Detection | |
| JPH0953999A (en) | Optical external force detector | |
| JPH06281414A (en) | Photo-integrated displacement measuring device | |
| JP2712509B2 (en) | Reflection film characteristic measuring device | |
| JPH11274643A (en) | Variable wavelength semiconductor laser light source |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 19990317 |