JPS60190812A - Position detector - Google Patents

Position detector

Info

Publication number
JPS60190812A
JPS60190812A JP22391684A JP22391684A JPS60190812A JP S60190812 A JPS60190812 A JP S60190812A JP 22391684 A JP22391684 A JP 22391684A JP 22391684 A JP22391684 A JP 22391684A JP S60190812 A JPS60190812 A JP S60190812A
Authority
JP
Japan
Prior art keywords
light
grating
diffraction grating
light beams
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.)
Granted
Application number
JP22391684A
Other languages
Japanese (ja)
Other versions
JPH0126005B2 (en
Inventor
Shigeo Moriyama
森山 茂夫
Tatsuo Harada
原田 達男
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.)
Hitachi Ltd
Original Assignee
Hitachi Ltd
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 Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP22391684A priority Critical patent/JPS60190812A/en
Publication of JPS60190812A publication Critical patent/JPS60190812A/en
Publication of JPH0126005B2 publication Critical patent/JPH0126005B2/ja
Granted legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01DMEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/32Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
    • G01D5/34Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
    • G01D5/36Forming the light into pulses
    • G01D5/38Forming the light into pulses by diffraction gratings

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Length Measuring Devices By Optical Means (AREA)
  • Optical Transform (AREA)

Abstract

PURPOSE:To make it possible to perform highly sensitive detection of a position, by interfering light beams having the same positive and negative degrees, which are inputted to a diffraction grating vertically, thereby using an extremely small grating constant. CONSTITUTION:Light from a point light source 1 in monochrome is made to be parallel light by a collimate lens 2 and veritcally inputted to the flat surface of the grating groove of a reflecting type diffraction grating 10. Diffracted light beams R1 and R2 having positive and negative degrees, respectively, are reflecteed in the directions determined by the incident wavelengths and a grating constant (d). In this case, there are the diffracted light beams having various degrees. But herein only a set of the light beams having the same degree is noted. The diffracted light beams R1 and R2 are reflected by parallel reflecting surfaces M1 and M2 and then inputted to a beam splitter 11. The transmitted diffracted light R1 and the reflected diffracted light R2 advance in the same direction and are interfered. Then the light beams are inputted to a photoelectric element 6. By reducing the grating constant (d) to the extremely small value, the highly sensitive detection of the position can be performed.

Description

【発明の詳細な説明】 〔発明の利用分野〕 本発明は、回折格子を用いた位置検出器に関する。[Detailed description of the invention] [Field of application of the invention] The present invention relates to a position detector using a diffraction grating.

〔発明の背景〕[Background of the invention]

従来、ミクロン・メートル(μm)単位の直線変位量を
計測する手段として、2枚の透過型回折格子を重ね合わ
ぜたいわゆるモアレ・スケールが広く用いられている(
例えば、Journal of Ph −ysics 
E:5cientific Instrument l
 972VOL5p−193−)。その−例を第1図に
示す。
Conventionally, a so-called moiré scale, which consists of two overlapping transmission gratings, has been widely used as a means of measuring linear displacement in micrometers (μm).
For example, Journal of Ph-physics
E:5 scientific instrument
972VOL5p-193-). An example of this is shown in FIG.

光源Iからの光はコリメータレンズ2によって平行光と
され、周期8μm程度の格子溝が形成されている主スケ
ール3を照射する。この主スケール3と同一周期の格子
溝を有するインテックス・スケール4が主スケール3に
向い合うように配置されていて、両スケール格子溝の幾
何的関係に応じて前記照射光は通過したり、遮蔽された
りする。
Light from a light source I is made into parallel light by a collimator lens 2, and is irradiated onto a main scale 3 in which grating grooves with a pitch of about 8 μm are formed. An Intex scale 4 having grating grooves with the same period as the main scale 3 is arranged to face the main scale 3, and depending on the geometric relationship between both scale grating grooves, the irradiated light can pass through or be blocked. Sometimes it happens.

通過した光は集光レンズ5により集光され、光電変換素
子6に入射してその光強度に応じた電気信号に変換され
る。格子溝周期か8μm程度のスケールを用いた場合、
主スケール3の移動に伴なって8μmを一周期とした正
弦状の信号となり、この信号の山数を計数することによ
り王スケールの移wJ量を計測することかできる。
The passing light is collected by a condensing lens 5, enters a photoelectric conversion element 6, and is converted into an electrical signal corresponding to the light intensity. When using a scale with a grating groove period of about 8 μm,
As the main scale 3 moves, a sinusoidal signal with one cycle of 8 μm is generated, and by counting the number of peaks of this signal, the amount of movement wJ of the king scale can be measured.

@2図は前記透過型スケール3の代わりに反射型回折格
子を用いる場合の一例である。光源1からの光はコリメ
ータレンズ2によって平行光とされ、反射型スケール7
に対し斜めに入射する。その結果、反射型スケール7の
格子溝の反射部分にあたった光は反射されるが、透過部
にあたった光は透過する゛か、または吸収されてしまう
ため、反射光束の断面は明暗の縞状となっている。そし
て、この縞は反射スケール7の移動と共に移動する。
Figure @2 is an example of a case where a reflection type diffraction grating is used instead of the transmission type scale 3. The light from the light source 1 is made into parallel light by the collimator lens 2, and the light from the reflective scale 7
incident at an angle to the As a result, the light that hits the reflective part of the grating groove of the reflective scale 7 is reflected, but the light that hits the transparent part is either transmitted or absorbed, so the cross section of the reflected light beam is a stripe of light and dark. The situation is as follows. This stripe moves as the reflective scale 7 moves.

この縞状反射光は集光レンズ5と反射鏡8の組6合わせ
により再び来た光路を逆もどりする。この逆もどりした
縞状反射光は反射スケール7の移動と共に移動するが、
反射鏡8によりその移動方向は反転している。この光は
再度反射スケール7の反射溝部分で反射され、レンズ2
、ハーフミラ−9を介して光電素子6に入射する。光電
素子6に入射する光強度は反射スケール7の移動と共に
正弦状の明暗となるが、上記したように反射鏡8で反射
されて逆もどりする光は反射スケール7と反対方向に移
動するため、その周期は格子前ピッチ(7) l / 
2となる。すなわち、変位感度は第1図のものに比べ2
倍になる。
This striped reflected light travels back along the optical path it came from by combining the condensing lens 5 and the reflecting mirror 8. This backward striped reflected light moves with the movement of the reflection scale 7,
The direction of movement is reversed by the reflecting mirror 8. This light is reflected again by the reflection groove part of the reflection scale 7, and is reflected by the lens 2.
, enters the photoelectric element 6 via the half mirror 9. The intensity of light incident on the photoelectric element 6 becomes bright and dark in a sinusoidal manner as the reflection scale 7 moves, but as mentioned above, the light reflected by the reflection mirror 8 moves in the opposite direction to the reflection scale 7. The period is the pitch before the grating (7) l/
It becomes 2. In other words, the displacement sensitivity is 2 compared to that in Figure 1.
Double.

上記した2棟類のモアレ・スケールでは、格子溝スケー
ルを単に明暗のスリット列としてしか用いておらず、格
子の回折現象を利用しているわけではない。そのため光
源lとして1m便な白色光を用いることができる反面、
変位感度を向上すべくスケールの格子ピッチを小さくす
ると逆に光の回折現象が無視できなくなり、たかだか5
μIn程度までしか格子ピッチを小さくできない欠点が
ある。
In the above-mentioned two types of moire scales, the grating groove scale is simply used as a row of bright and dark slits, and the diffraction phenomenon of the grating is not utilized. Therefore, while white light with a distance of 1 m can be used as a light source,
If the grating pitch of the scale is made smaller in order to improve the displacement sensitivity, the light diffraction phenomenon becomes impossible to ignore, and at most 5
There is a drawback that the grating pitch can only be reduced to about μIn.

上記の型式のモアレ・スケールと異なり、格子溝スケー
ルの回折光の干渉を利用したものが考えられている( 
0ptics &; 5pectroscopy Vo
L。
Different from the above-mentioned type of moiré scale, one that utilizes the interference of diffracted light from grating groove scales is being considered (
0ptics &; 5pectroscopy Vo
L.

L3p−295−)。第3図は、その例を示すものであ
る。単色の点光源1からの光はコリメータ・レンズ2に
より平行光とされた後にビームスプリッタ11に斜めに
入射し、その分割面において透過する光aと反射する光
すの2つに分割される。
L3p-295-). FIG. 3 shows an example. Light from a monochromatic point light source 1 is made into parallel light by a collimator lens 2, and then obliquely enters a beam splitter 11, where it is split into two parts, a transmitted light a and a reflected light, at its splitting surface.

それぞれの光は反射型回折格子10に斜めに入射し、回
折される。反射回折光の方向は、回折格子10の格子定
数41入射角および入射波長λによって決定され、それ
らを適当に選ぶと入射した方向へ回折させることが可能
である。この場合回折光は負の次数を持つものとなる。
Each light beam obliquely enters the reflection type diffraction grating 10 and is diffracted. The direction of the reflected diffracted light is determined by the incident angle of the grating constant 41 of the diffraction grating 10 and the incident wavelength λ, and by appropriately selecting them, it is possible to diffract the reflected diffracted light in the direction of incidence. In this case, the diffracted light has a negative order.

さて回折して入射光の光路を逆にたどった2つの光a’
 、b’はそれぞれ再びビームスプリッタ1■により2
分割される。ビームスプリッタ11を透過したa′とb
′の光はレンズ2、ハーフミラ−9を介して光電素子6
に入射する。この2つの光は可干渉であるため干渉し、
光強度に明暗を生じる。回折格子10の格子溝1/2本
分の距離d/2だけ変位すると電気信号は一周期の正弦
波を生ずる。この型式のものでは回折現象を利用してい
るため、光源としては可干渉なものであるこ仔 とが必要であるが、株子定数を小さくすることができ、
高感度な位1a検出器を得ることが可能である。
Now, the two lights a' that have been diffracted and traced the optical path of the incident light in opposite directions
, b' are each again 2 by beam splitter 1
be divided. a' and b transmitted through the beam splitter 11
'The light passes through the lens 2 and half mirror 9 to the photoelectric element 6.
incident on . These two lights are coherent, so they interfere,
Produces brightness and darkness in light intensity. When the electric signal is displaced by a distance d/2 corresponding to 1/2 of the grating grooves of the diffraction grating 10, the electric signal generates a sine wave with one period. Since this type of device uses diffraction phenomenon, it requires a coherent light source, but the stock constant can be made small.
It is possible to obtain a highly sensitive 1a detector.

しかし、第3図の形式のものを実施する上で次のような
欠点がある。すなわち、■)作動距離(物がぶつからな
い空間のきよりで、回折格子10とビームスプリッタ1
1間の距離をいう)を比較的大きくとりたい場合(例え
ば、10mm程度)には必然的に回折格子上に照射され
る2光束間の距離りが大きくなり、一定の移動距離を検
出するにはそれだけ長い回折格子が必要となること。
However, there are the following drawbacks in implementing the type shown in FIG. In other words, ■) working distance (the distance between the diffraction grating 10 and the beam splitter 1 in the space where objects do not collide)
If you want to take a relatively large distance (for example, about 10 mm), the distance between the two light beams irradiated onto the diffraction grating will inevitably become large, and it will be difficult to detect a fixed distance of movement. requires a longer diffraction grating.

2)光源からの入射光をビームスプリッタにより分割し
ており、その透過光はビームスプリッタの傾き角に影響
されないが、反射光はその傾き角に依存するため、回折
格子lOからの2つの反射回折光が良く干渉するようビ
ームスプリッタ11と光源lルンズ2等の光学軸を厳密
にアライメントする必要があり、逆にこの回折格子lO
が移動した場合には光学系が狂いやすいこと。そして、
3)お互いに干渉させる光が回折格子10の異なった2
つの部分によって回折された光どうしであるため、良好
な干渉性を得るためには特に均一な格子溝性能を有する
回折格子が必要となり、また格子上のゴミやキズの影響
を受けやすいこと、等。
2) The incident light from the light source is split by a beam splitter, and the transmitted light is not affected by the tilt angle of the beam splitter, but the reflected light depends on the tilt angle, so there are two reflections and diffraction from the diffraction grating lO. It is necessary to strictly align the optical axes of the beam splitter 11 and the light source luns 2, etc., so that the light interferes well, and conversely, this diffraction grating lO
If the lens moves, the optical system is likely to go awry. and,
3) The light to be interfered with each other is caused by two different diffraction gratings 10.
Since the light is diffracted by two parts, a diffraction grating with particularly uniform grating groove performance is required to obtain good coherence, and it is easily affected by dust and scratches on the grating. .

〔発明の目的〕[Purpose of the invention]

本発明は、上述した従来の欠点を解消した位置検出器を
提供するものである。
The present invention provides a position detector that eliminates the above-mentioned conventional drawbacks.

説明する。explain.

単色の黒光′m、1からの光はコリメート・レンズ2に
より平行光とされ、反射型回折格子10の格子溝平面に
゛垂直に入射させる。そうすると、入射波長さ格子定数
dから定まる方向にR1,R2のそれぞれ正負次数の回
折光が反射される。この場合、多数の次数の回折光が存
在するが、ここではただ−組の同一次数の光に注目する
。さて、回折光ill、R2はお互いに平行な反射面M
、L、M2によって反射された後にビームスプリッタ1
jに入射し、透過する回折光几lと反射される回折光R
2は同一方向に憩行して干渉し合い、光重素子6に入射
する。その干渉は回折格子10上の折点とビームスプリ
ッタ11によって再び合成されるで正弦状の信号が得ら
れる。
The light from the monochromatic black light 'm, 1 is made into parallel light by the collimating lens 2, and is made to be incident perpendicularly to the grating groove plane of the reflection type diffraction grating 10. Then, the diffracted lights of the positive and negative orders of R1 and R2 are reflected in directions determined by the incident wavelength and the grating constant d. In this case, there are diffracted lights of many orders, but here we will focus only on the set of lights of the same order. Now, the diffracted beams ill and R2 are reflected by a reflective surface M parallel to each other.
, L, after being reflected by M2 beam splitter 1
The diffracted light L that enters and passes through j and the diffracted light R that is reflected
2 travel in the same direction, interfere with each other, and enter the optical heavy element 6. The interference is combined again by the bending point on the diffraction grating 10 and the beam splitter 11 to obtain a sinusoidal signal.

以上説明したように、本発明では回折格子に垂直入射し
た光のそれぞれ正貝同仄数の光どうしを干渉させること
に特徴かあり、その結果、上述した従来の欠点を解消す
ることが可能となる。ずなわぢ、回折現象を利用してい
るため格子定数dを極めて小さく、たとえばd = 0
.8μm位のものも用いることができ、それだけ高感度
な位置検出が可能である。また回折格子に垂直入射させ
ることから光学系のアライメントが容易であり、さらに
直交格子溝を形成しである回折格子を用いることにより
、XY二次元の位置検出が可能となる。これについては
詳しく後述する。第4図では本発明の原理的構成を反射
型回折格子の例で説明しているが、これを透過型回折格
子とすることも当然可能である。
As explained above, the present invention is characterized by causing the same number of beams of light vertically incident on the diffraction grating to interfere with each other, and as a result, it is possible to eliminate the above-mentioned conventional drawbacks. Become. Zunawaji utilizes the diffraction phenomenon, so the lattice constant d is extremely small, for example d = 0.
.. It is also possible to use a material with a diameter of about 8 μm, which allows highly sensitive position detection. Further, alignment of the optical system is easy because the light is incident perpendicularly to the diffraction grating, and furthermore, by using a diffraction grating in which orthogonal grating grooves are formed, XY two-dimensional position detection becomes possible. This will be described in detail later. In FIG. 4, the basic structure of the present invention is explained using an example of a reflection type diffraction grating, but it is of course possible to use this as a transmission type diffraction grating.

第5図は、本発明の一実施例を説明する図である。光源
13は波長830nmのレーザ・タイオードを用い、そ
の光はコリメータレンズ2によって平行ビームとされて
反射型回折格子10に垂直に入射する。格子定数dを1
.6μr71(d場合、正負それぞれの一次回折光は約
40°の角度で反射回折し、ポロプリズムlもり、1%
2に入射する。両回折光はそれぞれのポロプリズムによ
りもと米だ方向に対射され、再び回折格子上の1点X2
に入射して再び回折される。ここでそれぞれの光路内に
はお互いに直交した偏光11(1+をもつ偏光&P1゜
P2が設けられているため、前記X2点での0次回折光
はさえきられる一方、回折格子10に垂直な方向に回折
する両回折光はお互いに直交した偏光而を有したままビ
ームスプリッタ11に入射する。このビームスプリッタ
を透過した両直線偏光は、それぞれの偏光面古さらに4
50の角度の偏光而を有する偏光板P3を通過してお互
いに可干渉な光となり、受光素子1〕1に入射する。他
方、ビームスプリッタ1工を反射した両直線偏光は偏光
板P3からさらに90°回転した偏光面を有する偏光板
P4を通過して受光素子D2に入射する。
FIG. 5 is a diagram illustrating an embodiment of the present invention. The light source 13 uses a laser diode with a wavelength of 830 nm, and its light is made into a parallel beam by the collimator lens 2 and enters the reflection type diffraction grating 10 perpendicularly. The lattice constant d is 1
.. 6μr71 (in the case of d, each of the positive and negative first-order diffraction lights is reflected and diffracted at an angle of about 40°, and the Porro prism l is 1%
2. Both diffracted lights are reflected in the horizontal direction by their respective Porro prisms, and are again focused on a point X2 on the diffraction grating.
and is diffracted again. Here, since polarized light 11 (polarized light &P1°P2 with 1+) which are perpendicular to each other are provided in each optical path, the 0th order diffracted light at the point X2 is blocked, while the The two diffracted lights enter the beam splitter 11 with their polarization planes orthogonal to each other.The two linearly polarized lights that have passed through this beam splitter are
The light passes through a polarizing plate P3 having a polarization angle of 50 degrees, becomes mutually coherent light, and enters the light receiving element 1]1. On the other hand, the linearly polarized light reflected by the beam splitter 1 passes through a polarizing plate P4 having a plane of polarization rotated by 90 degrees from the polarizing plate P3, and enters the light receiving element D2.

それぞれの受光素子1)l、D2から得られる信号SL
、82は、たとえは第6図(a)に示すように、回折格
子の移動量d/4(二0.4μm)を周期とし、位相が
お互いに90°ずれている正弦状の信号である。この正
弦信号の振11¥計11心のレヘル■1に対する1百号
の大小を比奴し、第6図(1))に示すごとく信号をテ
ジクル化した後、その信号の立上がりおよび立下がりで
第6図(C)のy口きパルス信号を発生させる。これら
の信号処理は既知の方法で行うことができる。
Signal SL obtained from each light receiving element 1)l, D2
, 82 are sinusoidal signals whose period is the amount of movement of the diffraction grating d/4 (20.4 μm) and whose phases are shifted by 90° from each other, as shown in FIG. 6(a). . After comparing the magnitude of this sine signal's amplitude of 11 yen to 11 cores of 100, and converting the signal into a technical signal as shown in Figure 6 (1)), the rising and falling edges of the signal are The Y-shaped pulse signal shown in FIG. 6(C) is generated. These signal processes can be performed using known methods.

以上の処理によりパルスは回折格子の移動量d/16(
二〇、1μm )ごとに発生ずることになり、これを計
数することにより移動量を知ることができる。本実施例
ではポロプリズムを用いて2度回折させているが、これ
は回折格子10の移動により回折格子にわずかな傾き等
を生じても、2つの回折光の進行方向を常に一致さぜ、
艮好な干渉を得るためである。また2度回折させるため
感度は、第4図のものに比べ2倍となっている。この感
度に対しては回折光としてさらに多数次どうしを干渉さ
せることにより、高感度とすることが可能である。また
ポロプリズムの代わりにキ−プ・コーナ等を用いても同
じ効果が得られるのは明らかである。
Through the above processing, the pulse is shifted by the amount of movement of the diffraction grating d/16 (
This occurs every 20.1 μm), and by counting this, the amount of movement can be determined. In this embodiment, a Porro prism is used to cause the diffraction to occur twice, but this allows the traveling directions of the two diffracted lights to always match even if the diffraction grating is slightly tilted due to movement of the diffraction grating 10.
The purpose is to obtain elegant interference. Furthermore, since the beam is diffracted twice, the sensitivity is twice as high as that of the one shown in FIG. This sensitivity can be increased by causing multiple orders to interfere with each other as diffracted light. It is also obvious that the same effect can be obtained by using a keep corner or the like instead of the Porro prism.

第7図は、本発明により二次元の位1d検出を行う場合
の実施例を示す図である。回折格子10′としてはX、
Y方向に直角に溝が形成されているもの(直角格子)を
用い、第5図と同様、回折格子10’に垂直にレーザビ
ームを入射する。その結果、それ゛ぞれ格子溝と直角な
4つの方向に光は反射回折され、ポロプリズムRλ+、
Rx−、几y+。
FIG. 7 is a diagram showing an embodiment in which two-dimensional digit 1d detection is performed according to the present invention. As the diffraction grating 10', X,
A diffraction grating 10' having grooves formed perpendicularly to the Y direction (a right-angled grating) is used, and a laser beam is incident perpendicularly onto the diffraction grating 10', as in FIG. As a result, the light is reflected and diffracted in four directions perpendicular to the grating grooves, and the porroprism Rλ+,
Rx-, y+.

Ry−に入射、反射される。ポロプリズムRx+とRX
−で反射された光は回折格子上の1点X2に集まり、再
び垂直に回折される。他方Y軸方向の光は点Y2で一致
する。
It is incident on Ry- and reflected. Porro prism Rx+ and RX
The light reflected by - is collected at one point X2 on the diffraction grating and is diffracted vertically again. On the other hand, the lights in the Y-axis direction coincide at point Y2.

このような光字系により、それぞれX軸、Y軸方向の回
折格子の移動をそれぞれ独立した回折光の干渉として得
ることができ、二次元の位置検出をすることができる。
With such an optical system, movement of the diffraction grating in the X-axis and Y-axis directions can be obtained as interference of independent diffracted lights, and two-dimensional position detection can be performed.

なお、図中、2’ 、11’。In addition, in the figure, 2', 11'.

13’ 、S、’、D、’ 、S2’ 、D2’ 、 
P3’、P4’はそれぞれ第5図に示した2 、11,
13.S、、Dl。
13', S,', D,', S2', D2',
P3' and P4' are 2, 11, and 11, respectively, shown in Figure 5.
13. S,,Dl.

S2 + D2 + ”3 + ”4と同様のものを示
し、またPx+、Pχ−はX方向に配置した偏光板、p
y+ 。
S2 + D2 + ``3 +'' 4 shows the same thing, and Px+ and Pχ- are polarizing plates arranged in the X direction, p
y+.

PY−はY方向に配置した偏光板を示す。PY- indicates a polarizing plate arranged in the Y direction.

〔発明の効果〕〔Effect of the invention〕

以上の説明より明らかなように、本発明によれば、移動
格子からl Om m程度離れていながら041μm単
位の位置検出が可能であり、焦点合わせの心安もない。
As is clear from the above description, according to the present invention, it is possible to detect the position in units of 041 μm even though the distance from the moving grating is about 1 Om m, and there is no need to worry about focusing.

また二次元の位置検出も容易であるので、XY移動台等
と組合わせ、座標検出を行う測定器や、精密位置決めが
必要な/?!r槙製造機械に応用できるなど、種々なる
利点を有し、実用に供してその効果は太きい。なお、本
発明は上記実施例で用いた具体的数値等に限定されるも
のではなく、適宜設定可能であることはいうまでもない
In addition, since two-dimensional position detection is easy, it can be combined with an XY moving table, etc., to create a measuring instrument that detects coordinates, or a system that requires precision positioning. ! It has various advantages such as being applicable to r-maki manufacturing machinery, and its effects are significant when put into practical use. Note that the present invention is not limited to the specific numerical values used in the above embodiments, and it goes without saying that they can be set as appropriate.

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

第1図乃至第3図は、それぞれ従来の位置検出器を示す
図、第4図は、本発明の基本的原理を説明する図、第5
図は、本発明の一実施例を示す図、第6図は、その信号
処理の一例を示す信号波形図、および第7図は、本発明
により二次元の位置検出を行う実施例を示す図である。 図中、■・・・点光源、2・・・コリメート・レンズ、
6・・・光電素子、lO・・・回折格子、11・・・ビ
ームス■1図 ′F32 図 嘉 5 図 第 4 図 手 4゛ε 捕 止 11:(方式) 60417 %式% (3 発明の名称 位 11“1′ 倹 出 ど;4補止をす
る考 ′1f件との関係 特許出願人 名 fホ (510)イス、式会礼 [−1きZifヴ
 作 所代 理 人 )11:)ヅ[刊oo東京都千代11」区丸の内−・」
川」5’(!′j1号株式会社1」立製作所内 電 話 東京212−1111(大代表)補正命令の1
コ1イ□I’ It!f 4’ll 60年3JJ26
1」補止の対象 明5ill ;!lの「発明の詳31
11な説明」の欄/−7〉\ 補正の内容 (1)明#m i!x、の第1頁第20行+41から第
2頁第2行目の記載を下記の通り訂正する。 記 [広く用いられている。このような技術を開示する公j
l1例としては、例えはジャーナルオフ フイジソグス
イー:サイエンティフインク インスツルメンh197
2第5巻第]93頁(,1ournal ofPhys
j、cs tE : 5cientifj、c Ins
trument 1 972 Vol、5. pi 9
3 )がある。その−例を第1図に示す。」 (2)明細専の第4頁第9行L1および第1−0行]」
の記1代を次の通り訂正する。 [られている。例えば、オプティソタスアンドスペク1
−ロスコピ第13巻第295頁(0ptics& 5p
ectroscopy Vol、 1.3 、 p29
5 )に記載されている。第3図は、その例を示すも」
Figures 1 to 3 are diagrams showing conventional position detectors, Figure 4 is a diagram explaining the basic principle of the present invention, and Figure 5 is a diagram showing the basic principle of the present invention.
6 is a diagram showing an example of the present invention, FIG. 6 is a signal waveform diagram showing an example of the signal processing, and FIG. 7 is a diagram showing an example of performing two-dimensional position detection according to the present invention. It is. In the figure, ■... point light source, 2... collimating lens,
6...Photoelectric element, lO...Diffraction grating, 11...Beams ■1 Figure F32 Figure 5 Name 11 "1'" 4.Relationship with supplementary consideration "1f" Patent applicant's name fho (510) chair, ceremony ceremony [-1ki Zifv creator agent person) 11:) ㅅ[Publication oo Tokyo Chiyo 11'' Ward Marunouchi--''
Kawa"5' (! 'j No. 1 Co., Ltd. 1" Tate Manufacturing Telephone: Tokyo 212-1111 (Major Representative) Amendment Order No. 1
Ko1i□I' It! f 4'll 60 years 3JJ26
1” Target of correction Akira 5 ill ;! ``Details of the invention 31''
11 Explanation” column/-7〉\ Contents of correction (1) Ming #m i! The description from page 1, line 20 +41 to page 2, line 2 of x is corrected as follows. [Widely used. Public companies disclosing such technology
For example, Journal Off Fujisogsui: Scientific Inc. Instrument h197
2 Volume 5] page 93 (, 1 Journal of Phys.
j, cs tE: 5cientifj, c Ins
trument 1 972 Vol, 5. pi9
3). An example of this is shown in FIG. (2) Page 4, line 9, L1 and lines 1-0, dedicated to details]
1st generation is corrected as follows. [It is being done. For example, Optisotas and Spec 1
- Rothkopi Volume 13, Page 295 (0ptics & 5p
electronoscopy Vol, 1.3, p29
5). Figure 3 shows an example of this.

Claims (1)

【特許請求の範囲】[Claims] ン動方向に対して垂直な格子溝を有する回折格子と、該
回折格子に単色平行光を垂直に入射せしめる手段と、該
回折格子により生起される回折光のうち一組の同一次数
の回折光をとり出して、これらを干渉せしめる手段と、
該干渉光を光電変換せしめて得られる電気信号をもとに
、該回折格子の移動位置を検出する手段を具備してなる
ことを特徴とする位置検出器。
a diffraction grating having grating grooves perpendicular to the direction of movement of the diffraction grating, means for making monochromatic parallel light perpendicularly incident on the diffraction grating, and a set of diffracted lights of the same order among the diffracted lights generated by the diffraction grating. means to extract and interfere with these,
A position detector comprising means for detecting the moving position of the diffraction grating based on an electric signal obtained by photoelectrically converting the interference light.
JP22391684A 1984-10-26 1984-10-26 Position detector Granted JPS60190812A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP22391684A JPS60190812A (en) 1984-10-26 1984-10-26 Position detector

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP22391684A JPS60190812A (en) 1984-10-26 1984-10-26 Position detector

Related Child Applications (1)

Application Number Title Priority Date Filing Date
JP10295690A Division JPH032520A (en) 1990-04-20 1990-04-20 Position detector

Publications (2)

Publication Number Publication Date
JPS60190812A true JPS60190812A (en) 1985-09-28
JPH0126005B2 JPH0126005B2 (en) 1989-05-22

Family

ID=16805720

Family Applications (1)

Application Number Title Priority Date Filing Date
JP22391684A Granted JPS60190812A (en) 1984-10-26 1984-10-26 Position detector

Country Status (1)

Country Link
JP (1) JPS60190812A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62163926A (en) * 1986-01-14 1987-07-20 Canon Inc Linear encoder
US4930895A (en) * 1987-06-15 1990-06-05 Canon Kabushiki Kaisha Encoder for forming interference fringes by re-diffracted lights from an optical type scale and photoelectrically converting the interference fringes to thereby detect the displacement of the scale
US5102226A (en) * 1989-01-12 1992-04-07 Matsushita Electric Works, Ltd. Optical measurement system for determination of an object profile
JP2013160760A (en) * 2012-02-01 2013-08-19 Dr Johannes Heidenhain Gmbh Position measuring device and equipment with a plurality of position measuring devices
WO2013161428A1 (en) * 2012-04-26 2013-10-31 株式会社ニコン Measurement method and encoder device, and exposure method and device

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5104225A (en) * 1991-01-25 1992-04-14 Mitutoyo Corporation Position detector and method of measuring position

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3630622A (en) * 1968-08-08 1971-12-28 Philips Corp Apparatus for determining the relative movement of an object by means of a grating mechanically connected to the object
US3756723A (en) * 1970-01-27 1973-09-04 Leitz Ernst Gmbh Method of measuring the displacement of an object and arrangement therefor
GB1367886A (en) * 1971-10-29 1974-09-25 Ti Group Serivces Ltd Measuring apparatus
JPS5174659A (en) * 1974-12-24 1976-06-28 Nippon Electric Co
JPS5245225A (en) * 1975-10-07 1977-04-09 Fujitsu Ltd Memory device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3630622A (en) * 1968-08-08 1971-12-28 Philips Corp Apparatus for determining the relative movement of an object by means of a grating mechanically connected to the object
US3756723A (en) * 1970-01-27 1973-09-04 Leitz Ernst Gmbh Method of measuring the displacement of an object and arrangement therefor
GB1367886A (en) * 1971-10-29 1974-09-25 Ti Group Serivces Ltd Measuring apparatus
JPS5174659A (en) * 1974-12-24 1976-06-28 Nippon Electric Co
JPS5245225A (en) * 1975-10-07 1977-04-09 Fujitsu Ltd Memory device

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62163926A (en) * 1986-01-14 1987-07-20 Canon Inc Linear encoder
US4930895A (en) * 1987-06-15 1990-06-05 Canon Kabushiki Kaisha Encoder for forming interference fringes by re-diffracted lights from an optical type scale and photoelectrically converting the interference fringes to thereby detect the displacement of the scale
US5102226A (en) * 1989-01-12 1992-04-07 Matsushita Electric Works, Ltd. Optical measurement system for determination of an object profile
JP2013160760A (en) * 2012-02-01 2013-08-19 Dr Johannes Heidenhain Gmbh Position measuring device and equipment with a plurality of position measuring devices
WO2013161428A1 (en) * 2012-04-26 2013-10-31 株式会社ニコン Measurement method and encoder device, and exposure method and device
JPWO2013161428A1 (en) * 2012-04-26 2015-12-24 株式会社ニコン Measuring method and encoder device, and exposure method and device

Also Published As

Publication number Publication date
JPH0126005B2 (en) 1989-05-22

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