JPH08114434A - Flatness measuring device - Google Patents
Flatness measuring deviceInfo
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- JPH08114434A JPH08114434A JP25197594A JP25197594A JPH08114434A JP H08114434 A JPH08114434 A JP H08114434A JP 25197594 A JP25197594 A JP 25197594A JP 25197594 A JP25197594 A JP 25197594A JP H08114434 A JPH08114434 A JP H08114434A
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- light
- positions
- reflected
- incident
- reflect
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- Length Measuring Devices By Optical Means (AREA)
- Length Measuring Devices With Unspecified Measuring Means (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、光の干渉作用によって
形成される干渉縞を利用して被検面の平面度を測定する
平面度測定装置に関し、詳しくは基準面および被検面に
対し斜め方向から光を照射する斜入射干渉法を用いた平
面度測定装置の改良に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flatness measuring device for measuring the flatness of a surface to be inspected by utilizing interference fringes formed by the interference effect of light. The present invention relates to an improvement of a flatness measuring device using oblique incidence interferometry in which light is obliquely irradiated.
【０００２】[0002]
【従来の技術】従来より、加工物表面の平面度を測定す
るための種々の干渉計装置が知られている。その中でも
凹凸差の大きい被検体表面の平面度を測定し得る装置と
して斜入射干渉計装置が知られている。2. Description of the Related Art Conventionally, various interferometer devices for measuring the flatness of a work surface are known. Among them, the grazing incidence interferometer device is known as a device capable of measuring the flatness of the surface of a subject having a large unevenness.
【０００３】この斜入射干渉計装置は、平行平板状の基
準原器の表面に斜め方向から可干渉光を入射せしめ、裏
面（基準面）から射出してこの裏面と対向させた被検体
の被検面上に照射し、上記裏面と被検面各部の距離に基
づく光路差に応じた干渉縞をスクリーン上に形成せしめ
るようにしたものであって、その詳細な内容は、例えば
本出願人が既に出願した特願平6-60894 号明細書に示さ
れている。This oblique-incidence interferometer device makes coherent light incident on the surface of a parallel plate-shaped reference standard device from an oblique direction, emits it from the back surface (reference surface), and opposes the back surface. Irradiation on the inspection surface, to form an interference fringes according to the optical path difference based on the distance between the back surface and each portion of the inspection surface on the screen, the detailed content, for example, the applicant It is shown in Japanese Patent Application No. 6-60894, which has already been filed.
【０００４】ところで、干渉計においてコントラストの
よい干渉縞を得るためには、特に被検面からの反射光量
と基準面からの反射光量とが同等となるように両表面の
反射率を合わせることが必要となる。In order to obtain interference fringes with good contrast in an interferometer, it is necessary to match the reflectances of both surfaces so that the amount of reflected light from the surface to be inspected and the amount of reflected light from the reference surface are equal. Will be needed.
【０００５】特に、近年、干渉計自体の外光遮蔽技術や
光ノイズ低減技術の進歩に伴ない低反射率を有する被検
面を測定する環境が整備されてきたため、このような低
反射率の被検面を干渉計を用いて測定する試みもなされ
ているが、このような低反射率の被検面の測定において
は元々の反射光量が不足しているため、上述した２つの
面からの反射光の光量を厳密に合わせコントラストを良
好なものとしないと解析可能な干渉縞を得ることは困難
であった。Particularly, in recent years, an environment for measuring a surface to be inspected having a low reflectance has been developed with the progress of the external light shielding technology and the optical noise reduction technology of the interferometer itself. Attempts have also been made to measure the surface to be inspected using an interferometer, but in the measurement of the surface to be inspected having such a low reflectance, the amount of originally reflected light is insufficient. It is difficult to obtain an interference fringe that can be analyzed unless the amount of reflected light is strictly adjusted and the contrast is made good.
【０００６】[0006]
【発明が解決しようとする課題】しかしながら、前述し
た斜入射干渉計装置においては、基準原器の裏面（基準
面）から射出された光の被検面からの反射光（物体光）
と、該裏面（基準面）からの内面反射光（参照光）とに
より光干渉を行なわせることとなるが、被検面が低反射
率の場合、物体光の光量は微かとなり、上記裏面からの
参照光の光量をこの微かな光量に合わせることが困難で
あった。However, in the above-mentioned oblique incidence interferometer device, the light emitted from the back surface (reference surface) of the reference prototype is reflected light (object light) from the surface to be inspected.
And the inner surface reflected light (reference light) from the back surface (reference surface) causes optical interference. However, when the surface to be inspected has a low reflectance, the light amount of the object light becomes small, and It was difficult to match the light quantity of the reference light of 1 to this minute light quantity.
【０００７】本発明は、このような事情に鑑みなさたれ
ものであり、斜入射干渉法を用いて低反射率の被検面の
平面度を測定する場合に、この被検面からの反射光量と
参照光の光量を合致させることのできる平面度測定装置
を提供することを目的とするものである。The present invention has been made in view of the above circumstances, and when measuring the flatness of a test surface having a low reflectance by using the oblique incidence interferometry, the amount of light reflected from the test surface is measured. It is an object of the present invention to provide a flatness measuring device capable of matching the light amounts of the reference light and the reference light.
【０００８】[0008]
【課題を解決するための手段】本発明の平面度測定装置
は、斜入射された可干渉光を射出して被検体上に照射す
ると共に、該可干渉光を内面反射して得た参照光と該可
干渉光の該被検体の表面からの反射光である物体光を互
いに干渉せしめる平行平面板を備えた平面度測定装置に
おいて、前記参照光が、前記可干渉光を前記平行平面板
の両面で複数回に亘り内面反射して得られるように構成
されてなり、前記可干渉光が複数回に亘り内面反射され
る前記両面上の位置であって、前記被検体への照射光が
射出される位置および該可干渉光の該被検体の表面から
の反射光が入射する位置以外の位置のうち少なくとも１
つに光反射部材を設けてなることを特徴とするものであ
る。The flatness measuring apparatus of the present invention emits coherent light that is obliquely incident and irradiates the subject with the coherent light, and reflects the coherent light by internal reflection. And a flatness measuring device comprising a plane-parallel plate for interfering with each other the object light that is the reflected light from the surface of the subject of the coherent light, the reference light, the coherent light of the parallel plane plate It is configured to be obtained by internally reflecting multiple times on both sides, and the coherent light is a position on the both surfaces that is internally reflected multiple times, and the irradiation light to the subject is emitted. At least one position other than the position where the reflected light from the surface of the subject of the coherent light is incident
It is characterized in that it is provided with a light reflecting member.
【０００９】[0009]
【作用および発明の効果】上述した如く構成された本発
明の平面度測定装置によれば、平行平面板に斜入射され
た可干渉光をこの平行平面板の両面で複数回に亘り内面
反射せしめて参照光を形成しており、その複数回の反射
によって参照光の光量を容易に低減させることができ
る。According to the flatness measuring apparatus of the present invention constructed as described above, the coherent light obliquely incident on the parallel plane plate is internally reflected on both sides of the parallel plane plate a plurality of times. The reference light is formed in this way, and the light quantity of the reference light can be easily reduced by the multiple reflections.
【００１０】しかも、この複数回の反射のうち少なくと
も１回の反射は平行平面板の表面に設けられた光反射部
材により行なわれるので、この光反射部材の反射率を変
更することにより、参照光の光量を、低反射率の被検面
からの反射光量に厳密に合わせた値に設定することがで
きるので、低反射率の被検面の形状測定を行なう際にも
コントラストの良好な干渉縞を形成することができる。Moreover, since at least one of the plurality of reflections is performed by the light reflecting member provided on the surface of the plane-parallel plate, the reference light can be changed by changing the reflectance of the light reflecting member. Can be set to a value that exactly matches the amount of light reflected from the surface to be inspected with low reflectance, so that an interference fringe with good contrast can be obtained even when measuring the shape of the surface to be inspected with low reflectance. Can be formed.
【００１１】また、平行平面板の両面において可干渉光
を複数回に亘り内面反射させる際に、被検体の照射光が
射出される位置および被検面からの反射光が入射する位
置以外の上記複数の反射位置のうち観察側の反射位置に
高反射率の光反射部材を設ければ、この観察側に、光量
が同等の２系の参照光が射出されることがなくゴースト
のない干渉縞画像を得ることができる。Further, when the coherent light is internally reflected multiple times on both surfaces of the plane-parallel plate, the above-mentioned points other than the position where the irradiation light of the object is emitted and the position where the reflected light from the surface to be inspected are incident. If a light-reflecting member having a high reflectance is provided at a reflection position on the observation side among a plurality of reflection positions, interference fringes having no ghost can be generated on the observation side without the emission of the two-system reference lights having the same light amount. Images can be obtained.
【００１２】[0012]
【実施例】以下、本発明の実施例について図面を参照し
ながら説明する。Embodiments of the present invention will be described below with reference to the drawings.
【００１３】第１図は本発明の実施例に係る平面度測定
装置を示す側面図である。この装置は、可干渉光を射出
する半導体レーザ光源１と、この半導体レーザ光源１か
らの光を平行光３とするコリメータレンズ２と、この平
行光３を斜め方向から入射され、この一部を透過せしめ
るとともに、残りを平面度の高い両基準面４ａ，４ｂに
より、複数回に亘って反射する透明ガラス製の平行平面
板からなる基準原器４を備えている。FIG. 1 is a side view showing a flatness measuring apparatus according to an embodiment of the present invention. This apparatus includes a semiconductor laser light source 1 that emits coherent light, a collimator lens 2 that converts the light from the semiconductor laser light source 1 into parallel light 3, and the parallel light 3 that is incident from an oblique direction and partially The reference prototype 4 is made of a plane parallel plate made of transparent glass, which is transparent and reflects the rest by a plurality of reference surfaces 4a and 4b having high flatness a plurality of times.
【００１４】また基準原器４の両基準面４ａ，４ｂの光
反射位置（ＣＣ位置、ＤＤ位置、Ｅ位置）には、金属蒸
着膜よりなる光反射部材11ａ，11ｂが設けられている。At the light reflection positions (CC position, DD position, E position) of both reference surfaces 4a and 4b of the reference prototype 4, light reflection members 11a and 11b made of a metal vapor deposition film are provided.
【００１５】さらに、上記基準原器４は、その基準面４
ａと被検体６の被検面６ａとが所定の空気間隔を隔てて
平行、かつ対向するような位置に配されており、基準面
４ａから射出された可干渉光が被検面６ａ上に斜めに照
射され、その反射光である物体光が再び基準面４ａから
基準原器４内に入射して参照光との間で波面合成される
ようになっている。Further, the reference prototype 4 has the reference surface 4
a and the test surface 6a of the test object 6 are arranged in parallel and opposite to each other with a predetermined air gap, and the coherent light emitted from the reference surface 4a is placed on the test surface 6a. The object light which is obliquely irradiated and reflected from the object light is again incident on the reference standard 4 from the reference surface 4a and is wavefront synthesized with the reference light.
【００１６】このように構成された実施例装置におい
て、平行光３は基準原器４の上部の基準面４ｂ（基準面
４ａと平行であってこの基準面４ａと同程度の平面度を
有するのが望ましい）のＡＡ位置７に入射角θで斜入射
する。この入射光のうちの一部は基準面４ａのＢＢ位置
８で外部に射出され、被検面６ａで反射され、基準面４
ａのＦＦ位置９に再入射する。一方、上記基準面４ｂへ
の入射光のうち一部は基準面４ａで反射され、この後両
基準面４ａ，４ｂのＣＣ位置、ＤＤ位置、ＥＥ位置、Ｆ
Ｆ位置９において次々と反射されて参照光を生成する。
この参照光はＦＦ位置９で被検面６ａからの物体光と波
面合成され互いに干渉して基準面のＧＧ位置10から射出
され、これら参照光および物体光の光路差に応じた干渉
縞がスクリーン15上に投影される。In the apparatus of the embodiment thus constructed, the collimated light 3 has the reference plane 4b (which is parallel to the reference plane 4a and has the same degree of flatness as the reference plane 4a) above the reference prototype 4. Is desirable) at an AA position 7 with an incident angle θ. Part of this incident light is emitted to the outside at the BB position 8 of the reference surface 4a, reflected by the surface 6a to be measured, and
It re-enters the FF position 9 of a. On the other hand, a part of the incident light on the reference surface 4b is reflected by the reference surface 4a, and thereafter, the CC position, DD position, EE position, and F position of both reference surfaces 4a and 4b.
The light is reflected one after another at the F position 9 to generate reference light.
This reference light is wavefront synthesized with the object light from the surface 6a to be inspected at the FF position 9, interferes with each other and is emitted from the GG position 10 on the reference surface, and interference fringes corresponding to the optical path difference between the reference light and the object light are displayed on the screen. Projected on 15.
【００１７】このスクリーン15上に投影された干渉縞は
この基準原器４の上方の観察者13に観察され、この干渉
縞の縞間隔等に基づき上記被検面６ａの平面度が測定さ
れる。The interference fringes projected on the screen 15 are observed by an observer 13 above the reference prototype 4, and the flatness of the surface 6a to be measured is measured based on the fringe spacing of the interference fringes. .
【００１８】また、光反射部材11ａ，11ｂが設けられて
いない位置であって、光の光入射部７，９および光射出
部８，10とはなっていない両基準面４ａ，４ｂの各位置
にはノイズとなる光をカットするための、砂ずり処理に
よる粗面が形成されている。Further, at the positions where the light reflecting members 11a and 11b are not provided, and the positions of both reference surfaces 4a and 4b which are not the light incident portions 7 and 9 and the light emitting portions 8 and 10 of the light. A rough surface is formed by sanding for cutting light that becomes noise.
【００１９】また、上記光反射部材11ａ，11ｂは、Ａｌ
等金属を蒸着することによって形成されたものであり、
この厚みをコントロールすることで光反射率を所望の値
に設定することができる。The light reflecting members 11a and 11b are made of Al.
It is formed by depositing a metal such as
By controlling this thickness, the light reflectance can be set to a desired value.
【００２０】上記スクリーン15は紙、布あるいはスリガ
ラス等を用いて形成する。このようにして形成されたス
クリーン15は透過光を散乱光に変えるため観察者13はス
クリーン15上の干渉縞全体を見ることが可能となる。The screen 15 is formed using paper, cloth, frosted glass or the like. The screen 15 thus formed changes the transmitted light into scattered light, so that the observer 13 can see the entire interference fringes on the screen 15.
【００２１】なお、この観察者13の位置にテレビカメラ
等の撮像手段を配設すれば上記干渉縞を記録することが
可能となる。If an image pickup means such as a television camera is provided at the position of the observer 13, the interference fringes can be recorded.
【００２２】なお、このスクリーン15と観察者13との間
に結像光学系を配設するのが実用上好ましい。It is practically preferable to dispose an imaging optical system between the screen 15 and the observer 13.
【００２３】上述したように構成された実施例装置によ
れば、可干渉光を基準原器４の両基準面４ａ，４ｂの間
で複数回に亘り反射せしめ、しかも両基準面４ａ，４ｂ
のＣＣ，ＤＤ，ＥＥの各位置においては所望の反射率を
有する光反射部材11ａによって可干渉光を反射せしめて
参照光を生成しており、これにより、参照光の光量を被
検面６ａからの物体光の光量に応じた、所望の低い値に
容易に設定できるようになっている。According to the embodiment apparatus configured as described above, the coherent light is reflected a plurality of times between the reference surfaces 4a and 4b of the reference prototype 4, and both reference surfaces 4a and 4b are reflected.
At each of CC, DD, and EE positions, the coherent light is reflected by the light reflecting member 11a having a desired reflectance to generate the reference light, whereby the light amount of the reference light is changed from the surface 6a to be measured. The desired low value can be easily set according to the light amount of the object light.
【００２４】すなわち、図２に示すように、基準面４ａ
のＢおよびＦの各位置における反射率がｒ、光反射部材
11ａ，11ｂが設けられたＣ，Ｄ，Ｅ各位置における反射
率をｒ′、被検面６ａの反射率をＲ、基準面４ａのＢ位
置における透過率をｔ、平行光３の元々の光量を１とし
た場合に、物体光と参照光の光量を略同程度に設定しよ
うとすれば下記条件式（１）を満足する必要がある。That is, as shown in FIG. 2, the reference surface 4a
The reflectance at each position of B and F is r, and the light reflecting member
The reflectance at each of C, D, and E positions where 11a and 11b are provided is r ', the reflectance at the surface 6a to be measured is R, the transmittance at the position B of the reference surface 4a is t, and the original light amount of the parallel light 3 is obtained. When is set to 1, if the light amounts of the object light and the reference light are set to be substantially the same, it is necessary to satisfy the following conditional expression (1).
【００２５】 Ｒｔ2 ≒ｒ2 ｒ′3 ……（１） したがって、光反射部材11ａ，11ｂの反射率ｒ′は、Rt 2 ≈r 2 r ′ 3 (1) Therefore, the reflectance r ′ of the light reflecting members 11 a and 11 b is
【００２６】[0026]
【数１】 [Equation 1]
【００２７】により導出すればよい。It may be derived by
【００２８】ここでｒ＝0.1 、ｔ＝0.9 、Ｒ＝0.01とす
れば、上記（２）式によりｒ′≒0.932 となる。Here, if r = 0.1, t = 0.9, and R = 0.01, then r'.apprxeq.0.932 according to the above equation (2).
【００２９】すなわち、被検面６ａの反射率が１％であ
れば、光反射部材11ａ，11ｂの反射率を略93.2％に設定
すればよいことになる。That is, if the reflectance of the surface 6a to be inspected is 1%, the reflectance of the light reflecting members 11a and 11b should be set to approximately 93.2%.
【００３０】このように本実施例では、基準面４ｂのＣ
ＣおよびＥＥの各位置において高反射率の光反射部材11
ａ，11ｂを設けていることから、これら各位置から観察
者13側に射出される参照光が極めて小さくなりこれらの
参照光と物体光により、いわゆる干渉縞のゴーストの発
生を防止することができる。As described above, in this embodiment, the C of the reference surface 4b is
Light reflecting member 11 having high reflectance at each position of C and EE
Since a and 11b are provided, the reference light emitted from the respective positions to the observer 13 side is extremely small, and it is possible to prevent the so-called interference fringe ghost from being generated by the reference light and the object light. .
【００３１】また、本発明装置においては参照光を複数
回反射させるようにしていることから、参照光と物体光
との間で光路長が大きく異なるため、平行光３の干渉性
を良好とすることが必要となる。Further, since the reference light is reflected a plurality of times in the device of the present invention, the optical path length between the reference light and the object light is largely different, so that the coherence of the parallel light 3 is improved. Will be required.
【００３２】これを、上記実施例の場合について説明す
る。This will be described in the case of the above embodiment.
【００３３】すなわち、平行光３の基準面４ｂへの入射
角をθ、屈折角をθ′、基準面４ａ，４ｂ上における反
射光線幅をＰ、基準原器４の厚みをｔ、基準面４ａと被
検面６ａの距離をｄ、空気の屈折率を１、基準原器４の
屈折率をｎとした場合、 sin θ＝ｎ sinθ′ ……（３） また、基準原器４内のＢＢ位置からＦＦ位置に至るまで
の光通過距離Ｄ1 は４ｔ／ cosθ′であるから、この光
通過距離Ｄ1 内に含まれる波数ｋ1 はThat is, the incident angle of the parallel light 3 on the reference surface 4b is θ, the refraction angle is θ ′, the reflected light beam width on the reference surfaces 4a and 4b is P, the thickness of the reference prototype 4 is t, and the reference surface 4a. When the distance between the target surface 6a and the test surface 6a is d, the refractive index of air is 1, and the refractive index of the reference standard 4 is n, sin θ = n sin θ ′ (3) since light passing distance D 1 up to the FF position is 4t / cos [theta] 'from the position, the wave number k 1 included in the light passing distance D 1 is
【００３４】[0034]
【数２】 [Equation 2]
【００３５】で表わされる。It is represented by
【００３６】また、基準原器４外のＢＢ位置からＦＦ位
置に至るまでの光通過距離Ｄ2 は２ｄ／ cosθであるか
ら、この光通過距離Ｄ2 に含まれる波数ｋ2 はFurther, since the light passing distance D 2 from the reference standard 4 out of the BB position to the FF position is 2d / cos [theta], the wave number k 2 contained in the light passage distance D 2 is
【００３７】[0037]
【数３】 (Equation 3)
【００３８】で表わされる。It is represented by
【００３９】ここで距離Ｄ1 と距離Ｄ2 の波数差ｋ′
は、Here, the wave number difference k ′ between the distance D 1 and the distance D 2
Is
【００４０】[0040]
【数４】 [Equation 4]
【００４１】で表わされる。It is represented by
【００４２】 また、Ｐ＝２ｔ tanθ′＝ｄ tanθ ……（７） であるから、Further, since P = 2t tan θ ′ = d tan θ (7),
【００４３】[0043]
【数５】 (Equation 5)
【００４４】となる。It becomes
【００４５】ここで、θ＝85°、ｎ＝1.5 とすれば、
（３）式によりθ′＝ 41.62°となる。Here, if θ = 85 ° and n = 1.5,
According to equation (3), θ '= 41.62 °.
【００４６】また、Ｐ＝20mmとすると、（７）式および
（８）式により、ｔ≒11.26 mm、ｄ＝1.8 mmとなり、ｄ
の値は基準面に対して非接触で測定できる。When P = 20 mm, t≈11.26 mm and d = 1.8 mm according to the equations (7) and (8), and d
The value of can be measured without contact with the reference surface.
【００４７】したがって（６）式により、Therefore, according to the equation (6),
【００４８】[0048]
【数６】 (Equation 6)
【００４９】となる。It becomes
【００５０】すなわち、上記実施例で干渉縞を得るため
には平行光３のコヒーレント長を49mm以上とする必要が
ある。That is, in order to obtain interference fringes in the above embodiment, the coherent length of the parallel light 3 must be 49 mm or more.
【００５１】なお、本発明の平面度測定装置としては上
記実施例のものに限られるものではなく、その他種々の
態様の変更が可能である。The flatness measuring apparatus of the present invention is not limited to the above-mentioned embodiment, and various other modifications can be made.
【００５２】例えば上記２つの実施例装置においては光
源として半導体レーザ光源を用いているが、この光源と
しては良好な干渉性のある光を射出する光源であればよ
く、例えばＨｅ−Ｎｅレーザ光源等の他のレーザ光源で
あってもよい。For example, although the semiconductor laser light source is used as the light source in the above-mentioned two embodiments, the light source may be any light source that emits light with good coherence, such as a He-Ne laser light source. Other laser light sources may be used.
【００５３】また、参照光を得るために基準原器４内を
内面反射させる回数は上記実施例のものに限られるもの
ではなく、所望の参照光の光量や設定する光反射部材の
反射率に応じて適宜選択することが可能である。Further, the number of times that the inside of the standard prototype 4 is internally reflected in order to obtain the reference light is not limited to that in the above-mentioned embodiment, and the desired quantity of the reference light and the reflectance of the light reflecting member to be set are set. It is possible to select it appropriately.
【００５４】また、光反射部材としては、スパッタリン
グ法等を用いて形成した薄層としてもよく、さらには別
体の反射部材を密接して取り付けるようにしてもよい。The light reflecting member may be a thin layer formed by a sputtering method or the like, or a separate reflecting member may be closely attached.
【００５５】また、被検面と対向する基準面から参照光
を射出し、物体光との間で光干渉を行なわせることも可
能である。Further, it is also possible to emit the reference light from the reference surface facing the surface to be inspected to cause optical interference with the object light.
【００５６】さらに、基準原器の厚み、屈折率、基準面
への平行光の入射角、基準面と被検面の間隔等も適宜選
択することが可能である。Further, the thickness of the reference prototype, the refractive index, the angle of incidence of the parallel light on the reference surface, the distance between the reference surface and the surface to be inspected, etc. can be appropriately selected.
【図１】本発明の実施例に係る平面度測定装置を示す概
略図FIG. 1 is a schematic diagram showing a flatness measuring apparatus according to an embodiment of the present invention.
【図２】図１に示す実施例装置の内容を説明するための
概略図FIG. 2 is a schematic diagram for explaining the contents of the apparatus of the embodiment shown in FIG.
１ 半導体レーザ光源 ２ コリメータレンズ ３ 平行光 ４ 基準原器 ４ａ，４ｂ 基準表面 ６ 被検体 ６ａ 被検面 ７，９ 光入射部 ８，10 光射出部 11ａ，11ｂ 光反射部材 13 観察者 15 スクリーン 1 semiconductor laser light source 2 collimator lens 3 parallel light 4 reference standard 4a, 4b reference surface 6 test object 6a test surface 7, 9 light incident part 8, 10 light emitting part 11a, 11b light reflecting member 13 observer 15 screen
Claims (1)
上に照射すると共に、該可干渉光を内面反射して得た参
照光と該可干渉光の該被検体の表面からの反射光である
物体光を互いに干渉せしめる平行平面板を備えた平面度
測定装置において、 前記参照光が、前記可干渉光を前記平行平面板の両面で
複数回に亘り内面反射して得られるように構成されてな
り、 前記可干渉光が複数回に亘り内面反射される前記両面上
の位置であって、前記被検体への照射光が射出される位
置および該可干渉光の該被検体の表面からの反射光が入
射する位置以外の位置のうち少なくとも１つに光反射部
材を設けてなることを特徴とする平面度測定装置。1. A reference light obtained by internally reflecting the coherent light and emitting the coherent light that is obliquely incident and irradiating the coherent light from the surface of the subject. In a flatness measuring device provided with parallel plane plates that interfere with each other as object light, which is reflected light, the reference light is obtained by internally reflecting the coherent light on both sides of the parallel plane plate a plurality of times. A position on the both surfaces where the coherent light is internally reflected a plurality of times, where the irradiation light to the subject is emitted and the coherent light of the subject. A flatness measuring device comprising a light reflecting member provided in at least one of the positions other than the position where the reflected light from the surface is incident.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25197594A JPH08114434A (en) | 1994-10-18 | 1994-10-18 | Flatness measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25197594A JPH08114434A (en) | 1994-10-18 | 1994-10-18 | Flatness measuring device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH08114434A true JPH08114434A (en) | 1996-05-07 |
Family
ID=17230790
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP25197594A Withdrawn JPH08114434A (en) | 1994-10-18 | 1994-10-18 | Flatness measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH08114434A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010539458A (en) * | 2007-09-14 | 2010-12-16 | ライカ ジオシステムズ アクチエンゲゼルシャフト | Surface measuring method and measuring apparatus |
-
1994
- 1994-10-18 JP JP25197594A patent/JPH08114434A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010539458A (en) * | 2007-09-14 | 2010-12-16 | ライカ ジオシステムズ アクチエンゲゼルシャフト | Surface measuring method and measuring apparatus |
| US9127929B2 (en) | 2007-09-14 | 2015-09-08 | Leica Geosystems Ag | Method and measuring device for gauging surfaces |
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