JPH026002B2 - - Google Patents

Info

Publication number
JPH026002B2
JPH026002B2 JP10934982A JP10934982A JPH026002B2 JP H026002 B2 JPH026002 B2 JP H026002B2 JP 10934982 A JP10934982 A JP 10934982A JP 10934982 A JP10934982 A JP 10934982A JP H026002 B2 JPH026002 B2 JP H026002B2
Authority
JP
Japan
Prior art keywords
light
polarizing beam
beam splitter
target
reflected
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
Application number
JP10934982A
Other languages
Japanese (ja)
Other versions
JPS58225304A (en
Inventor
Eiji Ogita
Toshitsugu Ueda
Yutaka Ono
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Yokogawa Electric Corp
Original Assignee
Yokogawa Electric Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Yokogawa Electric Corp filed Critical Yokogawa Electric Corp
Priority to JP10934982A priority Critical patent/JPS58225304A/en
Publication of JPS58225304A publication Critical patent/JPS58225304A/en
Publication of JPH026002B2 publication Critical patent/JPH026002B2/ja
Granted legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B9/00—Measuring instruments characterised by the use of optical techniques
    • G01B9/02—Interferometers
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B2290/00—Aspects of interferometers not specifically covered by any group under G01B9/02
    • G01B2290/70—Using polarization in the interferometer

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Instruments For Measurement Of Length By Optical Means (AREA)
  • Length Measuring Devices By Optical Means (AREA)

Abstract

PURPOSE:To measure the three-dimensional mechanical quantity by causing an interference between a speckle pattern formed with a mobile diffusion surface and a reference light from a fixed reflection surface. CONSTITUTION:Light from a light source 1 irradiates a target 4 passing through a first polarized beam splitter 21. The light reflected from the target 4 enters a light receiver 7 reflected with the first PBS21. The light which enters the first PBS21 from the light source 1 and passes through first and second PBSs 21 and 22 reflected with a mirror 6 enters a light receiver 7 as reference light. A speckle pattern is formed on the light receiver 7 in such a manner as to be overlapped by a Michelson interference fringe. The three-dimensional mechanical quantity is measured from the movement of the speckle pattern and the movement of the interference fringe.

Description

【発明の詳細な説明】 本発明は、光の干渉を利用して変位量、変位速
度、振動数等の機械量を知るようにした光学式機
械量測定装置に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical mechanical quantity measuring device that uses optical interference to determine mechanical quantities such as displacement amount, displacement speed, and vibration frequency.

本発明の目的は、被測定物体とは非接触でその
３次元の各種機械量を高精度、高分解能で測定す
ることのできる構造簡単な、この種の装置を実現
しようとするものである。 An object of the present invention is to realize a device of this kind, which has a simple structure and can measure various three-dimensional mechanical quantities of an object to be measured with high precision and high resolution without contacting the object.

本発明に係る装置は、光源からの可干渉光を被
測定機械量が与えられる可動拡散面と、固定反射
面に照射し、可動拡散面からの拡散光によつてで
きるスペツクルパターンと固定定反射面からの参
照光とを干渉させてスペツクルパターンに干渉稿
を重畳させ、スペツクルパターンの移動及び干渉
稿の移動から３次元の機械量測定を行なうように
したものである。 The apparatus according to the present invention irradiates coherent light from a light source onto a movable diffusing surface to which a mechanical quantity to be measured is given and a fixed reflecting surface, and produces a speckle pattern and a fixed constant by the diffused light from the movable diffusing surface. An interference pattern is superimposed on the speckle pattern by interfering with a reference light from a reflecting surface, and three-dimensional mechanical quantity measurement is performed from the movement of the speckle pattern and the movement of the interference pattern.

第１図は本発明に係る装置の一例を示す構成説
明図である。図において、１は光源で、例えば
HeNeレーザ光源が使用され、ここから可干渉な
光が出射される。１１，１２はレンズで、光源１
から出射した光を拡げて平行光とするビームエク
スパンダBXを構成している。２１は第１の偏光
ビームスプリツタ（以下PBSと略す）で、ビー
ムエクスパンダBXを通つて入射する光源１から
の光ビームを、２方向に分割する。２２は第２の
PBSで、第１のPBSに対して45゜回転して設置さ
れており、ここに入射する２種の光を干渉させて
縞を作る役目をしている。３１，３２はそれぞれ
焦点距離が1，2のレンズ、３０はレンズ３１と
３２との間であつて、レンズ３１から1、レンズ
３２から2の距離に設置した絞り板で、これに
は、径ｄの透孔が設けられている。４は拡散面４
０を有するターゲツトで、レンズ３２からｌ（ｌ
は０〜22程度が好ましい）だけ離れて設置され
ており、これには、例えば図示のようにｘ，ｙ，
ｚ方向の３次元の測定機械量が与えられる。５１
はレンズ３２とターゲツト４との間に設置した
λ／４板、６はミラーで、光源１の光軸Clに対し
て僅かな角度Δ0だけ傾斜して設置されており、
第１のPBS２１で分割された光源１からの光ビ
ームが入射する。５２は第１のPBS２１とミラ
ー６との間に設置したλ／４板、７は第２の
PBS２２から出射した光を受光する受光器であ
る。 FIG. 1 is a configuration explanatory diagram showing an example of a device according to the present invention. In the figure, 1 is a light source, for example
A HeNe laser light source is used, which emits coherent light. 11 and 12 are lenses, and light source 1
It constitutes a beam expander BX that expands the light emitted from the beam into parallel light. A first polarizing beam splitter (hereinafter abbreviated as PBS) 21 splits the light beam from the light source 1, which is incident through the beam expander BX, into two directions. 22 is the second
This is a PBS that is rotated 45 degrees from the first PBS, and its role is to create stripes by interfering with the two types of light that enter it. 31 and 32 are lenses with focal lengths of 1 and 2 , respectively; 30 is a diaphragm plate installed between the lenses 31 and 32 at a distance of 1 from the lens 31 and 2 from the lens 32; A through hole d is provided. 4 is the diffusion surface 4
0, l(l
(preferably about 0 to 22 ), and this includes, for example, x, y,
A three-dimensional measured mechanical quantity in the z-direction is given. 51
is a λ/4 plate installed between the lens 32 and the target 4, and 6 is a mirror, which is installed at a slight angle Δ0 with respect to the optical axis Cl of the light source 1.
A light beam from the light source 1 divided by the first PBS 21 enters. 52 is a λ/4 plate installed between the first PBS 21 and the mirror 6, and 7 is the second
This is a light receiver that receives the light emitted from the PBS 22.

第２図は、この受光器７の受光面の構成例を示
す平面図である。ここには、例えば多数個の受光
素子をアレイ状に配列して構成されるCCDなど
のイメージセンサ７１，７２を、受光素子の配列
方向が互いに直交するように設置して構成してあ
る。 FIG. 2 is a plan view showing an example of the structure of the light receiving surface of this light receiver 7. As shown in FIG. Here, image sensors 71 and 72 such as CCDs, which are configured by arranging a large number of light receiving elements in an array, are installed so that the arrangement directions of the light receiving elements are orthogonal to each other.

第３図は第１図装置において、電気的な回路を
示す構成ブロツク図である。この図において、７
０は、例えばCCDで構成された各受光器７１，
７２を駆動するクロツク発振器で、例えば周波数
cのクロツク信号を各受光器に印加している。８
１，８２は各受光器７１，７２からの出力周波数
信号x，yを入力し、これと参照周波数信号R1
とをミキシングするミキサ、８３は受光器７１か
らの周波数信号xを入力し、これと参照周波数
信号R2とをミキシングするミキサ、９１，９２，
９３はそれぞれ対応するミキサからの出力信号の
なかの特定な周波数信号を通過させるローパスフ
イルタ、４１，４２，４３はそれぞれローパスフ
イルタ９１，９２，９３からの周波数信号を計数
するカウンタ、６は各カウンタ４１，４２，４３
からの計数信号1，2，3を入力する演算回路
で、この演算回路としては、例えばマイクロプロ
セツサが使用される。６０は表示装置で、例えば
CRTが使用され、演算回路６での演算結果を表
示する。 FIG. 3 is a block diagram showing an electrical circuit in the apparatus shown in FIG. 1. In this figure, 7
0 is each light receiver 71 configured with a CCD, for example.
A clock oscillator that drives 72, e.g.
A clock signal of c is applied to each photoreceiver. 8
1 and 82 input the output frequency signals x and y from each photoreceiver 71 and 72, and this and the reference frequency signal R1
A mixer 83 inputs the frequency signal x from the photoreceiver 71, and mixers 91, 92, and 83 mix this and the reference frequency signal R2 .
93 is a low-pass filter that passes a specific frequency signal in the output signal from the corresponding mixer; 41, 42, and 43 are counters that count the frequency signals from the low-pass filters 91, 92, and 93, respectively; and 6 is each counter. 41, 42, 43
This is an arithmetic circuit that inputs counting signals 1 , 2 , and 3 from a microprocessor, and for example, a microprocessor is used as this arithmetic circuit. 60 is a display device, for example
A CRT is used to display the calculation results of the calculation circuit 6.

このように構成した装置の動作は次の通りであ
る。光源１から出射された波長λの光は、ビーム
エクスパンダBXで拡げられ、平行光となつて第
１のPBS２１に入射する。ここに入射した光の
うち、入射面に対して振動方向が平行な光成分
（Ｐ波）は、ここを通過し、レンズ３１、絞り板
３０、レンズ３２及びλ／４板５１を経てターゲ
ツト４の拡散面４０に平行光となつて照射され
る。ターゲツト４の拡散面４０に照射された平行
光は、この拡散面の凹凸によつてランダムな位相
変調を受けて反射し、この反射光は、再びλ／４
板５１、レンズ３２、絞り板３０、レンズ３１を
通つて戻り、第１のPBS２１に入射する。ここ
で、レンズ３１、絞り板３０、レンズ３２は、こ
こを通過する光の空間周波数を下げるローパスフ
イルタとして機能しており、必ずしも必要でな
い。第１のPBSに再入射する光は、λ／４板５
１を２度通過したので、90゜偏波面が回転してＳ
波となつており、このPBS２１で反射して、第
２のPBS２２に入射する。一方光源１から第１
のPBS２１に入射した光のうち、８波成分は、
ここで反射し、λ／４板５２を通つて、ミラー６
で反射し、再びλ／４板５２を通つて、第１の
PBS２１に再入射する。この光はＰ波となつて
おり、このPBS２１を通過して、第２のPBS２
２に参照光として入射する。第２のPBS２２は、
第１のPBS２１に対して45゜回転して置かれてお
り、ここで、互いに偏波面が90゜異なるターゲツ
ト４からの反射光と、光源１からミラー６で反射
してくる参照光とのうち、第４図に示すように
45゜成分のものが透過し、受光器７上に干渉稿が
つくられる。なお、第２のPBS２２は、偏光板
を用いてもよい。 The operation of the device configured as described above is as follows. Light with a wavelength λ emitted from the light source 1 is expanded by the beam expander BX, becomes parallel light, and enters the first PBS 21. Of the light incident here, the light component (P wave) whose vibration direction is parallel to the incident plane passes through here, passes through the lens 31, the aperture plate 30, the lens 32, and the λ/4 plate 51, and reaches the target 4. The parallel light is irradiated onto the diffusing surface 40 of the light beam. The parallel light irradiated onto the diffusing surface 40 of the target 4 undergoes random phase modulation and is reflected by the unevenness of this diffusing surface, and this reflected light is again λ/4
The light returns through the plate 51, lens 32, aperture plate 30, and lens 31, and enters the first PBS 21. Here, the lens 31, the aperture plate 30, and the lens 32 function as a low-pass filter that lowers the spatial frequency of light passing through them, and are not necessarily necessary. The light re-entering the first PBS is transmitted through the λ/4 plate 5
1 twice, the polarization plane rotates by 90° and S
It becomes a wave, is reflected by this PBS 21, and enters the second PBS 22. On the other hand, from light source 1 to
Of the light incident on PBS21, the 8 wave components are:
It is reflected here, passes through the λ/4 plate 52, and passes through the mirror 6.
, passes through the λ/4 plate 52 again, and passes through the first
Re-enters PBS21. This light is a P wave, passes through this PBS21, and is transmitted to the second PBS2.
2 as a reference light. The second PBS22 is
It is placed rotated by 45 degrees with respect to the first PBS 21, and here, between the reflected light from the target 4 whose plane of polarization differs by 90 degrees from each other and the reference light reflected from the light source 1 by the mirror 6, , as shown in Figure 4.
The 45° component is transmitted, and an interference pattern is created on the photoreceiver 7. Note that the second PBS 22 may use a polarizing plate.

第５図は、受光器７上に得られたパターンの一
例を示す図であつて、スペツクルパターンSPに、
マイケルソン干渉縞が重畳したものとなる。そし
て、このパターンにおいて、ターゲツト４がｘ
（ｙ）方向へ変位すると、スペツクルパターンSP
は第５図において、ｘ（ｙ）方向に移動する。ま
た、ターゲツト４がｚ方向へ変位すると、マイケ
ルソン干渉稿MPはｘ方向へ変位し、そのときス
ペツクルパターンSPは動かない。 FIG. 5 is a diagram showing an example of a pattern obtained on the light receiver 7, and shows a speckle pattern SP.
This results in superimposed Michelson interference fringes. In this pattern, target 4 is x
When displaced in the (y) direction, the speckle pattern SP
moves in the x (y) direction in FIG. Furthermore, when the target 4 is displaced in the z direction, the Michelson interference pattern MP is displaced in the x direction, and at this time the speckle pattern SP does not move.

ここで、レンズ３１，３２の距離が1＋2であ
ることと、ターゲツト４に平面波が照射されるよ
うにすれば、所謂純移動状態となり、この状態で
は、受光器７の受光面に得られるスペツクルパタ
ーンの、平均的スペツクル径は、（1・λ）／
（π・ｄ）で与えられる。また、干渉稿の平均ピ
ツチはλ／sinΔ0で与えられ、ひとつのスペツク
ルパターンの中には、５〜10本の縞が入るように
選ぶのが望ましい。したがつて、レンズ３２とタ
ーゲツト４との間の距離ｌや、レンズ３１から受
光器７までの距離は、純移動状態、スペツクル
径、干渉稿のピツチには無関係となる。 Here, if the distance between the lenses 31 and 32 is 1 + 2 and the target 4 is irradiated with a plane wave, a so-called pure movement state will occur, and in this state, a The average speckle diameter of the speckle pattern is ( 1・λ)/
It is given by (π・d). Further, the average pitch of the interference pattern is given by λ/sinΔ0, and it is desirable to select so that 5 to 10 stripes are included in one speckle pattern. Therefore, the distance l between the lens 32 and the target 4 and the distance from the lens 31 to the light receiver 7 are independent of the pure movement state, the speckle diameter, and the pitch of the interference pattern.

受光器７の各受光器７１，７２は、一端にクロ
ツク発振器７０から周波数cのクロツク信号が印
加されて駆動されており、各受光器７１，７２か
らo＝c／Ｎ（ただしＮは受光器７１，７２のビ
ツト数）を基本周波数とする周波数信号x，y
が出力される。 Each of the light receivers 71 and 72 of the light receiver 7 is driven by applying a clock signal of frequency c from the clock oscillator 70 to one end, and from each light receiver 71 and 72 o=c/N (where N is the light receiver). Frequency signals x, y whose fundamental frequency is 71, 72 bit numbers)
is output.

第６図は、各受光器７１から得られる周波数信
号xの周波数スペクトルを示す説明図である。
この信号のパワースペクトルは、基本周波数o
の整数倍の点でピークがあり、かつこれらのピー
クの包絡線はR2の周波数（R2≫R1とする）で、
干渉縞によるピークを有している。ここで、ター
ゲツト４がｘ方向にＸだけ移動すれば、ｍ次高調
波に相当するピークPmは、その移動速度dX／dt
に比例したfmxだけ周波数シフトする。また、タ
ーゲツト４がｚ方向に移動すれば、包絡線のピー
クが移動する。 FIG. 6 is an explanatory diagram showing the frequency spectrum of the frequency signal x obtained from each light receiver 71.
The power spectrum of this signal is the fundamental frequency o
There are peaks at points that are integer multiples of , and the envelope of these peaks is at the frequency of R2 (where R2 ≫ R1 ),
It has a peak due to interference fringes. Here, if the target 4 moves by X in the x direction, the peak Pm corresponding to the m-th harmonic will be equal to its moving speed dX/dt
Shift the frequency by fmx proportional to . Furthermore, if the target 4 moves in the z direction, the peak of the envelope moves.

第３図において、ミキサ８１，８２は各受光器
７１，７２から出力される周波数信号と、周波数
R1とをミキシング、すなわち、ヘテロダイン検
波し、各出力をローパスフイルタ９１，９２及び
カウンタ４１，４２を介することによつて、例え
ばｍ次高調波に相当するピークPmの、ターゲツ
ト４のｘ（ｙ）方向変位に伴う周波数シフト
Δmx、（Δmy）に対応した信号をそれぞれ得
る。演算回路６は、これらの信号を入力し、所定
の演算、例えば積分演算することによつて、ター
ゲツト４のｘ，ｙ方向の変位量Ｘ，Ｙを知ること
ができる。同じように、ミキサ８３は、受光器７
１から出力される周波数信号と、周波数R2とを
ミキシングし、ローパスフイルタ９３、カウンタ
４３を介することによつて、包絡線のピークのシ
フトΔzに対応した信号を得る。演算回路６は、
この信号を入力し、所定の演算をすることによつ
て、ターゲツト４のｚ方向の変位量Ｚを知ること
ができる。なお、Δmx，Δmy，Δzは、いず
れもターゲツト４の移動方向に応じて正、負に極
性が変ることから、移動方向の判別も同時にでき
る。 In FIG. 3, mixers 81 and 82 combine the frequency signals output from each light receiver 71 and 72 with the frequency
By mixing R1 , that is, performing heterodyne detection, and passing each output through low-pass filters 91, 92 and counters 41, 42, x(y) of target 4 of peak Pm corresponding to m-th harmonic, for example Signals corresponding to the frequency shifts Δmx and (Δmy) accompanying the directional displacement are obtained, respectively. The arithmetic circuit 6 inputs these signals and performs a predetermined calculation, for example, an integral calculation, thereby being able to determine the amount of displacement X, Y of the target 4 in the x and y directions. Similarly, the mixer 83
A signal corresponding to the shift Δz of the peak of the envelope is obtained by mixing the frequency signal outputted from 1 and the frequency R2 and passing it through the low-pass filter 93 and the counter 43. The arithmetic circuit 6 is
By inputting this signal and performing a predetermined calculation, the amount of displacement Z of the target 4 in the z direction can be determined. Note that since the polarities of Δmx, Δmy, and Δz all change between positive and negative depending on the moving direction of the target 4, the moving direction can also be determined at the same time.

このように構成される装置は、ひとつの光源か
らのビームによつて３次元の変位が同時に測定で
きるもので、全体構成を簡単にできる。また、各
受光器から得られる信号は周波数信号であること
から、演算処理が容易であり、高分解能で各種機
械量を測定することができる。 The device configured in this manner can simultaneously measure three-dimensional displacement using a beam from one light source, and the overall configuration can be simplified. Furthermore, since the signals obtained from each light receiver are frequency signals, calculation processing is easy and various mechanical quantities can be measured with high resolution.

なお、上記の実施例において、ミラー６は、入
射光と反射光とがΔθ傾くものならば、他の構成、
例えば、頂角がπ′／２＋Δθ／２のプリズムやキ
ユーブコーナーを用いてもよい。また、ここで
は、受光器７１，７２としてCCDのようなイメ
ージセンサを用いることを想定したが、空間フイ
ルタを組合せたようなパターン検出器を用いても
よい。また、光パワーに余裕があれば第７図に示
すようにハーフミラー２３を用いるような光学系
としてもよい。また、ここではターゲツト４の
ｘ，ｙ，ｚ方向の変位量を測定する場合を説明し
たが、ターゲツト４の変位速度、振動数、回転数
あるいは形状変化等、各種の３次元の機械量を測
定することができる。 In the above embodiment, the mirror 6 may have other configurations as long as the incident light and the reflected light are inclined by Δθ.
For example, a prism or a cube corner with an apex angle of π'/2+Δθ/2 may be used. Moreover, although it is assumed here that image sensors such as CCDs are used as the light receivers 71 and 72, a pattern detector such as a combination of spatial filters may be used. Alternatively, if there is sufficient optical power, an optical system using a half mirror 23 as shown in FIG. 7 may be used. In addition, although we have explained here the case of measuring the amount of displacement of the target 4 in the x, y, and z directions, it is also possible to measure various three-dimensional mechanical quantities such as the displacement speed, vibration frequency, rotation speed, or shape change of the target 4. can do.

以上説明したように、本発明に係る装置によれ
ば、被測定機械量が与えられるターゲツトとは非
接触で、このターゲツトの３次元の変位量などの
機械量を高分解能で測定することができる。 As explained above, according to the device according to the present invention, it is possible to measure mechanical quantities such as three-dimensional displacement of a target with high resolution without contacting the target to which the mechanical quantity to be measured is given. .

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

第１図は本発明に係る装置の一例を示す構成説
明図、第２図は第１図装置に用いられている受光
器の構成説明図、第３図は電気的回路を示す構成
ブロツク図、第４図は受光器に照射される光の偏
波面の説明図、第５図は受光器の受光面につくら
れるパターンの一例を示す説明図、第６図は受光
器から得られる信号の周波数スペクトルを示す説
明図、第７図は本発明の他の光学系の要部を示す
説明図である。 １…光源、２１，２２…偏光ビームスプリツ
タ、３１，３２…レンズ、３０…絞り板、４…タ
ーゲツト、４０…拡散面、５１，５２…λ／４
板、６…ミラー、７…受光器。 FIG. 1 is a configuration explanatory diagram showing an example of a device according to the present invention, FIG. 2 is a configuration explanatory diagram of a light receiver used in the device shown in FIG. 1, and FIG. 3 is a configuration block diagram showing an electric circuit. Figure 4 is an explanatory diagram of the polarization plane of light irradiated to the optical receiver, Figure 5 is an explanatory diagram showing an example of the pattern created on the light receiving surface of the optical receiver, and Figure 6 is the frequency of the signal obtained from the optical receiver. FIG. 7 is an explanatory diagram showing the spectrum, and FIG. 7 is an explanatory diagram showing the main parts of another optical system of the present invention. 1... Light source, 21, 22... Polarizing beam splitter, 31, 32... Lens, 30... Aperture plate, 4... Target, 40... Diffusion surface, 51, 52... λ/4
Plate, 6...mirror, 7...light receiver.

Claims (1)

【特許請求の範囲】 １ 可干渉な光を出射する光源と、 ｘ軸、ｙ軸、ｚ軸方向に変位する被測定機械量
が与えられるターゲツトと、 前記光源からの光を２方向に分割する偏光ビー
ムスプリツタと、 この偏光ビームスプリツタで分割された一方の
光をλ／４板を介して前記ターゲツトに照射する
と共に、ターゲツトからの反射光を前記λ／４板
を介して前記偏光ビームスプリツタに導く光学系
と、 前記偏光ビームスプリツタで分割された他方の
光をλ／４板を介して、前記光源からの光の光軸
に対して所定の角度をもつて設置されたミラーに
照射すると共に、当該ミラーからの反射光をλ／
４板を介して前記偏光ビームスプリツタに導く光
学系と、 多数個の受光素子がアレイ状に配列され、かつ
各受光素子の配列方向が互いに直交する第１、第
２のイメージセンサからなり、前記偏光ビームス
プリツタで反射した前記ターゲツトからの拡散光
と前記偏光ビームスプリツタを通過した前記ミラ
ーからの反射光とを受光する受光手段と、 前記偏光ビームスプリツタと前記受光手段との
間に設置され、前記受光手段上に干渉縞を作るた
めの偏光手段と、 前記第１、第２のイメージセンサを駆動するク
ロツク発振器と、 前記第１及び第２のイメージセンサからの出力
周波数信号x，yをそれぞれ入力し、これと第
１の参照周波数信号R１とをミキシングする第
１、第２のミキサ８１，８２と、 前記第１のイメージセンサからの出力周波数信
号xを入力し、これと第２の参照周波数信号R
２とをミキシングする第３のミキサ８３と、 前記第１、第２及び第３の各ミキサからの周波
数信号をそれぞれローパスフイルタ９１〜９３を
介して計数する第１、第２及び第３のカウンタ４
１〜４３と、 これらの各カウンタからの信号をそれぞれ入力
し、所定の演算を行う演算回路と を備え、 前記受光手段上に得られるスペツクルパターン
の移動から前記ターゲツトのｘ軸方向及びｙ軸方
向の機械量を、前記受光手段上に得られる干渉縞
の移動から前記ターゲツトのｚ軸方向の機械量を
それぞれ知るようにしたことを特徴とする光学式
機械量測定装置。[Claims] 1. A light source that emits coherent light; a target to which mechanical quantities to be measured are displaced in the x-axis, y-axis, and z-axis directions; and the light from the light source is split into two directions. a polarizing beam splitter; one of the lights split by the polarizing beam splitter is irradiated onto the target via a λ/4 plate, and the reflected light from the target is irradiated to the polarizing beam splitter via the λ/4 plate; an optical system that guides the other light split by the polarizing beam splitter to the polarizing beam splitter, and a mirror installed at a predetermined angle with respect to the optical axis of the light from the light source, passing the other light split by the polarizing beam splitter through a λ/4 plate. At the same time, the reflected light from the mirror is λ/
an optical system that guides the polarizing beam to the polarizing beam splitter via four plates, and first and second image sensors in which a large number of light receiving elements are arranged in an array, and the arrangement directions of the light receiving elements are orthogonal to each other, a light receiving means for receiving the diffused light from the target reflected by the polarizing beam splitter and the reflected light from the mirror that has passed through the polarizing beam splitter; and between the polarizing beam splitter and the light receiving means. polarizing means for creating interference fringes on the light receiving means; a clock oscillator for driving the first and second image sensors; output frequency signals x from the first and second image sensors; first and second mixers 81 and 82 which respectively input y and mix this and the first reference frequency signal R1; and input the output frequency signal x from the first image sensor and mix this and the first reference frequency signal R1. 2 reference frequency signal R
a third mixer 83 that mixes the frequency signals of the first, second, and third mixers; and first, second, and third counters that count the frequency signals from the first, second, and third mixers via low-pass filters 91 to 93, respectively. 4
1 to 43, and an arithmetic circuit that inputs signals from each of these counters and performs predetermined arithmetic operations. An optical mechanical quantity measuring device characterized in that the mechanical quantity in the z-axis direction of the target is determined from the movement of interference fringes obtained on the light receiving means.
JP10934982A 1982-06-25 1982-06-25 Optical type mechanical quantity measuring apparatus Granted JPS58225304A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10934982A JPS58225304A (en) 1982-06-25 1982-06-25 Optical type mechanical quantity measuring apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10934982A JPS58225304A (en) 1982-06-25 1982-06-25 Optical type mechanical quantity measuring apparatus

Publications (2)

Publication Number Publication Date
JPS58225304A JPS58225304A (en) 1983-12-27
JPH026002B2 true JPH026002B2 (en) 1990-02-07

Family

ID=14507969

Family Applications (1)

Application Number Title Priority Date Filing Date
JP10934982A Granted JPS58225304A (en) 1982-06-25 1982-06-25 Optical type mechanical quantity measuring apparatus

Country Status (1)

Country Link
JP (1) JPS58225304A (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8613635D0 (en) * 1986-06-05 1986-07-09 Tyrer J R Optical inspection
JPH03128405A (en) * 1989-10-12 1991-05-31 Keyence Corp Feed quantity detecting device for material of forming machine or the like
IE910326A1 (en) * 1991-01-31 1992-07-29 Mairead Rosario Reynolds A method and apparatus for detecting direction and¹displacement of a surface
JP2008096295A (en) * 2006-10-12 2008-04-24 Mitsutoyo Corp Three-dimensional sensor and contact probe

Also Published As

Publication number Publication date
JPS58225304A (en) 1983-12-27

Similar Documents

Publication Publication Date Title
US3891321A (en) Optical method and apparatus for measuring the relative displacement of a diffraction grid
EP0250306A2 (en) Angle measuring interferometer
TWI627388B (en) Grating measuring device
EP0244275B1 (en) Angle measuring interferometer
US3635552A (en) Optical interferometer
RU2638580C1 (en) Laser doppler velocity sensor
JPH026002B2 (en)
EP0405462B1 (en) Optical system for measuring linear or angular displacements
JP2023036027A (en) Heterodyne light source for use in metrology system
JPH0134082Y2 (en)
JPH045122B2 (en)
JPS6344136A (en) Heterodyne michelson interferometer related to polarimetry
US3419331A (en) Single and double beam interferometer means
JPS59162405A (en) Optical-type mechanical-quantity measuring device
JPH0141205B2 (en)
JPH0587518A (en) Interferometer for measuring rectilinear and up-and-down and left and right displacement
JP2779497B2 (en) Interferometer
JPH04155260A (en) Rotational speed measuring apparatus
JP2000018918A (en) Laser interference apparatus for detecting moving quantity of movable body
JPS60216207A (en) Optical measuring instrument for mechanical amount
RU2060475C1 (en) Method of measurement of harmonic oscillation amplitudes
JPS58225302A (en) Optical type mechanical quantity measuring apparatus
JPS6212442B2 (en)
SU1095033A1 (en) Polarization interferometer of shift
JP2023035989A (en) Digital holography metrology system