JP4326356B2 - Phase correction value measurement method - Google Patents

Phase correction value measurement method Download PDF

Info

Publication number
JP4326356B2
JP4326356B2 JP2004020349A JP2004020349A JP4326356B2 JP 4326356 B2 JP4326356 B2 JP 4326356B2 JP 2004020349 A JP2004020349 A JP 2004020349A JP 2004020349 A JP2004020349 A JP 2004020349A JP 4326356 B2 JP4326356 B2 JP 4326356B2
Authority
JP
Japan
Prior art keywords
light
measurement
interference
contact
measured
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 - Fee Related
Application number
JP2004020349A
Other languages
Japanese (ja)
Other versions
JP2005214740A (en
Inventor
雄一郎 横山
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.)
Mitutoyo Corp
Original Assignee
Mitutoyo 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 Mitutoyo Corp filed Critical Mitutoyo Corp
Priority to JP2004020349A priority Critical patent/JP4326356B2/en
Publication of JP2005214740A publication Critical patent/JP2005214740A/en
Application granted granted Critical
Publication of JP4326356B2 publication Critical patent/JP4326356B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Landscapes

  • Instruments For Measurement Of Length By Optical Means (AREA)
  • Length Measuring Devices By Optical Means (AREA)

Description

本発明は位相補正値測定方法、特に光波干渉測定による寸法測定値に対する位相補正値の測定方法の改良に関する。   The present invention relates to a method for measuring a phase correction value, and more particularly to an improvement in a method for measuring a phase correction value for a dimension measurement value by optical interference measurement.

従来より長さの基準として端度器が用いられている。端度器は両端の面間距離で規定の寸法を表す標準であり、代表的なものとしてブロックゲージがある。
このブロックゲージは極めて高い寸法精度をもち、その測定面が他のブロックゲージの測定面に容易に密着（リンギング）する。そして、数個のブロックゲージを密着することで必要な寸法が得られる。その反面、このブロックゲージは、測定面が常に他の測定面と接触するような使い方をするので、傷や摩耗を生じやすく、材料の経年変化もあり、定期的な検査が必要である。
ブロックゲージの相対向する端面間の寸法の校正を高精度に行うために、光波干渉測定装置が用いられている（特許文献１を参照）。さらに、特許文献２〜３に記載された非密着光波干渉測定装置では、ブロックゲージの両端面間から光を照射し、それぞれの端面からの反射光による干渉縞を用いて寸法測定をすることで、ブロックゲージをベースプレートにリンギングさせる必要がない非密着測定を行うことができる。 Conventionally, an end measure is used as a reference for length. The edge scale is a standard that represents a specified dimension by the distance between the surfaces of both ends, and a typical example is a block gauge.
This block gauge has extremely high dimensional accuracy, and its measurement surface is easily adhered (ringing) to the measurement surface of another block gauge. And a required dimension is obtained by sticking several block gauges. On the other hand, since this block gauge is used in such a way that the measurement surface always comes into contact with other measurement surfaces, it is easy to cause scratches and wear, and there is a secular change of the material, and a periodic inspection is necessary.
In order to calibrate the dimension between the opposing end faces of the block gauge with high accuracy, a light wave interference measuring apparatus is used (see Patent Document 1). Furthermore, in the non-contact optical interference measuring apparatus described in Patent Documents 2 and 3, light is irradiated from between both end faces of the block gauge, and the dimensions are measured using interference fringes by reflected light from the respective end faces. It is possible to perform non-contact measurement without having to block the block gauge to the base plate.

上述したようにブロックゲージは物理的な接触やリンギング等を伴った使用方法が前提である。そのため、端面間の寸法を測定する場合、両端面のそれぞれの粗さ曲線の最外部（特に突出する部分は除く）を測定位置として寸法を測定する。しかし、光波干渉測定では、表面粗さの問題、材質の光学的性質による光の反射時の位相変化の問題、の２点の問題でこの位置が測定位置とはならない。   As described above, the block gauge is premised on a usage method involving physical contact, ringing, and the like. Therefore, when measuring the dimension between the end faces, the dimension is measured using the outermost part (particularly excluding the protruding part) of the respective roughness curves on both end faces as the measurement position. However, in the light wave interference measurement, this position does not become the measurement position due to the two problems of the problem of surface roughness and the problem of phase change upon reflection of light due to the optical properties of the material.

図６に示すようにブロックゲージの端面は微視的には凹凸のある状態となっている。接触子を端面に接触して寸法を測る場合、図６（Ａ）のように接触子は凹凸の一番高い部分に触れることとなり、その部分を測定位置として寸法が測定される。しかしながら、光波干渉法で測定した場合、図６（Ｂ）のように、粗さ曲線の最上部からの反射光や、最下部からの反射光の重ね合わせた光で測定を行うため、反射面を特定できない。そのため、最上部と最下部の中間（粗さ曲線の算術平均粗さ）を測定位置とした寸法が測定される。よって、測定端面に粗さがある以上、表面最外部で測定することができず、機械的な接触による寸法よりも短く測定されてしまう。つまり、補正を行わないと、常に測りたい表面よりも潜り込んだ位置を測定するため、実際よりも短く測定されてしまう。また、表面粗さが大きいほど潜り込みの影響も大きくなる。この影響による位相変化を形状補正値と呼ぶ。   As shown in FIG. 6, the end surface of the block gauge is microscopically uneven. When the dimension is measured by bringing the contact element into contact with the end face, as shown in FIG. 6A, the contact element touches the highest uneven part, and the dimension is measured using that part as the measurement position. However, when the measurement is performed by the light wave interferometry, as shown in FIG. 6B, the measurement is performed using the reflected light from the uppermost part of the roughness curve or the reflected light from the lowermost part. Cannot be identified. Therefore, the dimension with the measurement position as the middle between the uppermost part and the lowermost part (arithmetic mean roughness of the roughness curve) is measured. Therefore, as long as the measurement end face has roughness, it cannot be measured at the outermost surface, and the measurement is shorter than the dimension due to mechanical contact. In other words, if correction is not performed, the position which is always submerged from the surface to be measured is measured, so that the measurement is shorter than the actual measurement. Also, the greater the surface roughness, the greater the influence of sinking. The phase change due to this influence is called a shape correction value.

また、測定表面が粗さのない理想面であったとしても、材質の光学的性質による光の位相変化の問題がある。垂直入射する光の反射時の位相変化は、複素屈折率の虚数部分（吸収係数）の小さい材質の場合は無視することができる。しかし、金属等のように吸収係数が大きい材質の場合、反射時の位相変化は無視することができない量となる。つまり、図６（Ｃ）に示すように反射時に光の位相の遅れが生じるため、見かけ上あたかも実際の表面よりも潜り込んだ中程の部分で測定を行った状態と同様な測定結果となる。このため、測定面が表面粗さのない理想面であったとしても、実際の寸法よりも短く測定されることになる。この影響による位相変化量を光学補正値という。
実際の測定では、形状補正値と光学補正値とを同時に考慮する必要があり、形状補正値と光学補正値との和を位相補正値と呼ぶ。この位相補正値を光波干渉測定による測定結果に加えることで前述の端面間における機械的寸法（両端面の粗さ曲線の最外部間の寸法）を求めることができる。 Even if the measurement surface is an ideal surface without roughness, there is a problem of phase change of light due to the optical properties of the material. The phase change during reflection of vertically incident light can be ignored in the case of a material having a small imaginary part (absorption coefficient) of the complex refractive index. However, in the case of a material having a large absorption coefficient such as metal, the phase change at the time of reflection is an amount that cannot be ignored. That is, as shown in FIG. 6C, a delay in the phase of the light occurs at the time of reflection, so that the measurement result is similar to the state in which the measurement is performed in the middle part that is submerged from the actual surface. For this reason, even if the measurement surface is an ideal surface with no surface roughness, the measurement is made shorter than the actual dimension. The amount of phase change due to this influence is called an optical correction value.
In actual measurement, it is necessary to consider the shape correction value and the optical correction value at the same time, and the sum of the shape correction value and the optical correction value is referred to as a phase correction value. By adding this phase correction value to the measurement result by the light wave interference measurement, the mechanical dimension between the end faces described above (the dimension between the outermost portions of the roughness curves on both end faces) can be obtained.

この位相補正値を求める方法として、従来より行われている補助ゲージ法について説明する。補助ゲージ法では、石英等を材質とするガラスが光学定数による位相変化がほとんどないことと、表面の粗さも無視できるくらい小さく加工可能であるという２つの特徴を利用して補正値をもとめるものである。まず、図７（Ａ）に示すように、同一材質同士をリンギングさせて測定を行う。つまり、位相補正値を測定したい材質のブロックゲージ（ＧＢ）を、同じ材質のブロックゲージ（ＧＢ）またはベースプレート（ＢＰ）にリンギングしそれぞれの測定面での反射時の位相変化を相殺する状態で光波干渉測定を行う。この測定で得られる寸法ＬＡは、ブロックゲージの寸法ＬＧＢ、リンギング層の厚さｄＷ、位相補正値Ｃとすると、
ＬＡ＝ＬＧＢ−Ｃ＋ｄＷ＋Ｃ＝ＬＧＢ＋ｄＷ
で表される。 As a method for obtaining this phase correction value, a conventional auxiliary gauge method will be described. In the auxiliary gauge method, the correction value is obtained by utilizing two characteristics that glass made of quartz or the like has almost no phase change due to optical constants and that the surface roughness can be negligibly small. is there. First, as shown in FIG. 7A, measurement is performed by ringing the same material. In other words, the light wave in a state where the block gauge (GB) of the material whose phase correction value is to be measured is ringed to the block gauge (GB) or the base plate (BP) of the same material to cancel the phase change at the time of reflection on each measurement surface. Perform interference measurements. When the dimension L A obtained by this measurement is the dimension L GB of the block gauge, the thickness d W of the ringing layer, and the phase correction value C,
L A = L GB −C + d W + C = L GB + d W
It is represented by

次に図７（Ｂ）に示すように補正値を測定したい材質のブロックゲージ（ＧＢ）に石英等のガラスのブロックゲージ（ＧＢ）またはベースプレート（ＢＰ）をリンギングさせて測定を行う。石英等のガラスは表面粗さが非常に小さく仕上げられており、また吸収係数が小さく光学定数による位相変化も無視できるレベルであるため、ベースプレート面上ではほとんど位相変化しない。この測定で得られるＬＢは、ブロックゲージの位相補正値Ｃを用いて、
ＬＢ＝ＬGB＋ｄｗ−Ｃ
と表される。ＬＡ，ＬＢの式から位相補正値Ｃは、
Ｃ＝ＬＢ−ＬＡ
と求められる。 Next, as shown in FIG. 7B, measurement is performed by ringing a block gauge (GB) of glass such as quartz or a base plate (BP) into a block gauge (GB) of a material whose correction value is to be measured. Glass such as quartz is finished with a very small surface roughness, and has a small absorption coefficient and a phase change due to an optical constant that can be ignored. Therefore, there is almost no phase change on the base plate surface. L B obtained by this measurement, using a phase correction value C of the block gauge,
L B = L GB + d w −C
It is expressed. From the equations of L A and L B, the phase correction value C is
C = L B -L A
Is required.

特開平６−３４１８０９号公報JP-A-6-341809 特開平８−２７１２１６号公報JP-A-8-271216 特開２００３−１９４５２３号公報JP 2003-194523 A

しかしながら、前述の従来方法はブロックゲージの寸法を測定する装置以外に特別な装置が必要ないという利点がある反面、測定の際にリンギングを伴うという問題がある。リンギングは作業そのものに熟練を要する上、再現性良く行うことが非常に困難である。上記の従来方法では、対象とするブロックゲージと同材質のベースプレートにリンギングさせた場合のリンギング層の厚さと、石英ガラス等のベースプレートにリンギングさせた場合のリンギング層の厚さとが等しいことが前提である。しかし、同一材質同士の場合と異なる材質同士の場合とではリンギング力が異なる等の理由から再現性よくリンギングを行うことは非常に難しく、前提通りにはならない。つまり、前提からのずれがそのまま系統誤差として現れる。   However, the above-described conventional method has an advantage that a special device other than the device for measuring the size of the block gauge is not necessary, but has a problem that ringing is involved in the measurement. Ringing requires skill in the work itself and is very difficult to perform with good reproducibility. In the above conventional method, it is assumed that the thickness of the ringing layer when ringing on the base plate made of the same material as the target block gauge is equal to the thickness of the ringing layer when ringing on a base plate such as quartz glass. is there. However, it is very difficult to perform ringing with good reproducibility because the ringing force is different between the same material and different materials, and it is not as expected. That is, the deviation from the premise appears as a systematic error as it is.

また、同一材質同士の密着測定時には二者の表面粗さや光学特性が等しく、それぞれで発生する位相変化が完全に相殺されていることが前提である。しかし、現実には二者の状態が全く同一ということはないため、前提通りにはならないという問題がある。このときの前提からのずれもまた系統誤差となる。
他の従来方法としてブロックゲージをガラス等のベースプレート上に積み重ねて測定を行う方法があるが、この方法もリンギングを用いるため、上記同様の問題が発生する。
また、リンギングを用いない従来方法としては表面粗さ及び光学定数を直接測定するという方法もある。しかし、この方法は、前述の形状補正値を粗さ測定機で、光学補正値をエリプソメータにより複素屈折率を測定することで求めなければならず、それぞれを測定するための測定装置が別途必要になるという問題がある。 Also, it is assumed that the surface roughness and optical characteristics of the two materials are equal when measuring the close contact between the same materials, and the phase changes that occur in each of them are completely offset. However, in reality, there is a problem that the two states are not exactly the same, so they are not as expected. A deviation from the premise at this time also becomes a systematic error.
As another conventional method, there is a method of performing measurement by stacking block gauges on a base plate such as glass. However, since this method also uses ringing, the same problem as described above occurs.
Further, as a conventional method that does not use ringing, there is a method of directly measuring the surface roughness and the optical constant. However, in this method, the above-mentioned shape correction value must be obtained by measuring the complex refractive index with a roughness measuring machine and the optical correction value with an ellipsometer, and a separate measuring device is required for measuring each. There is a problem of becoming.

光波干渉測定により求められるブロックゲージ等の端度器の寸法値には位相補正値を加算し、正しい値に補正する必要がある。そのため、寸法測定の不確かさをより低減するためには位相補正値の不確かさも低減しなければならない。現在、位相補正値測定はリンギングを用いた光波干渉計で測定しているが上記の理由から分かるようにリンギング層のばらつきにより安定した位相補正値を得ることが困難であった。
本発明は上記課題に鑑みなされたものであり、その目的は、簡易かつ高精度に光波干渉測定における位相補正値を測定する方法を提供することにある。 It is necessary to add a phase correction value to the size value of the edge gauge such as a block gauge obtained by the light wave interference measurement and correct it to a correct value. Therefore, in order to further reduce the uncertainty of dimension measurement, the uncertainty of the phase correction value must also be reduced. At present, the phase correction value is measured by a light wave interferometer using ringing. However, as can be seen from the above reason, it is difficult to obtain a stable phase correction value due to variations in the ringing layer.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for measuring a phase correction value in light wave interference measurement simply and with high accuracy.

本発明の位相補正値測定方法は、光を互いに可干渉な２光束に分け、一方を参照光、他方を測定光とし、測定光を測定対象物に照射し、その反射光と参照光とによる干渉に基づいて前記測定物の相対向する端面間の寸法測定を行う光波干渉測定での測定光の反射時の位相変化分を求める位相補正値測定方法において、
位相変化分ＣＸが未知の被測定物と位相変化分ＣＳが既知の基準物とを用意する工程と、
寸法測定の対象となる測定対象物の相対向する両端面へそれぞれ測定光を照射し、前記測定対象物の一方の端面からの反射光と参照光との干渉と、前記測定対象物の他方の端面からの反射光と参照光との干渉と、に基づいて前記測定対象物の光学的寸法を測定する非密着光波干渉測定装置を用いて、前記被測定物の光学的寸法ＬＩＸと前記基準物の光学的寸法ＬＩＳとの差である光学的寸法差ΔＬ Ｉ （ΔＬ Ｉ ＝ＬＩＸ −ＬＩＳ ）を求める工程と、
寸法測定の対象となる測定対象物の端面に接触子を接触させ、該接触子の接触位置に基づいて前記測定対象物の相対向する端面間の機械的寸法を測定する接触式の測長装置を用い、前記被測定物の機械的寸法Ｌ Ｘ と前記基準物の機械的寸法Ｌ Ｓ との差である機械的寸法差ΔＬ（ΔＬ＝Ｌ Ｘ −Ｌ Ｓ ）を接触式比較測定によって求める工程と、
前記光学的寸法差ΔＬ Ｉ 、前記機械的寸法差ΔＬ、及び前記基準物の位相変化量ＣＳから前記被測定物の位相変化分ＣＸを次の式、
ＣＸ＝ＣＳ ＋ΔＬ／２−ΔＬ Ｉ ／２
によって求める工程と、を含むことを特徴とする。
ここで、光学的寸法差ΔＬ Ｉ （ΔＬ Ｉ ＝Ｌ ＩＸ −Ｌ ＩＳ ）の記載について、括弧内の式は、括弧前の符号（ΔＬ Ｉ ）の意味を定義するものである。従って、光学的寸法差ΔＬ Ｉ を求める工程は、括弧内の個々の値Ｌ ＩＸ 、Ｌ ＩＳ をそれぞれ測定し、その差をとって間接的に光学的寸法差ΔＬ Ｉ を算出する方法に限られるものではなく、光学的寸法差ΔＬ Ｉ のみを測定する方法でもよい。 In the phase correction value measuring method of the present invention, light is divided into two coherent light beams, one is used as reference light, the other is used as measurement light, the measurement light is irradiated onto the measurement object, and the reflected light and reference light are used. In the phase correction value measurement method for obtaining the phase change amount at the time of reflection of the measurement light in the light wave interference measurement for measuring the dimension between the opposite end faces of the measurement object based on the interference,
Preparing a measurement object whose phase change C X is unknown and a reference object whose phase change C S is known;
Irradiate measurement light to both opposite end surfaces of the measurement object to be dimensioned, interference between the reflected light from one end surface of the measurement object and the reference light, and the other of the measurement object Using a non-contact optical interference measuring apparatus that measures the optical dimension of the measurement object based on the interference between the reflected light from the end surface and the reference light, the optical dimension L IX of the object to be measured and the reference Determining an optical dimension difference ΔL I (ΔL I = L I X −L I S ) which is a difference from the optical dimension L IS of the object;
A contact-type length measuring device that contacts a contact surface with an end surface of a measurement object to be dimensioned and measures a mechanical dimension between opposing end surfaces of the measurement object based on a contact position of the contact device. And obtaining a mechanical dimension difference ΔL (ΔL = L X −L S ) , which is a difference between the mechanical dimension L X of the object to be measured and the mechanical dimension L S of the reference object, by contact-type comparative measurement When,
Said optical dimensional difference [Delta] L I, the mechanical dimensions difference [Delta] L, and the phase change amount C X the following equation of the object to be measured from the phase variation amount C S of the reference object,
C X = C S + ΔL / 2 -ΔL I / 2
And a step of obtaining by the following.
Here, in the description of the optical dimensional difference ΔL I (ΔL I = L IX −L IS ), the formula in parentheses defines the meaning of the sign (ΔL I ) before the parentheses . Therefore, the process for obtaining the optical size difference [Delta] L I, limited to the method of calculating the individual values L IX, the L IS were measured indirectly optically dimensional differences [Delta] L I taking the difference in parentheses not, it may be a method of measuring only the optical size difference [Delta] L I.

上記の位相補正値測定方法において、前記非密着光波干渉測定装置は、所定のビーム径及び波長を持つ光を照射する光照射手段と、前記光照射手段から照射された光を二光束に分割する光分割手段と、測定対象物の測長軸と一致する光軸を有する第１干渉手段及び第２干渉手段と、前記第１干渉手段及び第２干渉手段の干渉縞をそれぞれ観察する第１観察手段と第２観察手段と、を備え、
前記光分割手段により分割された二光束の一方の光束は、前記第１干渉手段に入射し、該光束の一部は第１参照光となり、残りは前記第１干渉手段により前記測定対象物の測長軸方向に反射され、
前記光分割手段により分割された二光束の他方の光束は、前記第２干渉手段に入射し、該光束の一部は第２参照光となり、残りは前記第２干渉手段により前記測定対象物の測長軸方向に反射され、
前記第１干渉手段から前記測定対象物の測長軸方向へ反射された光は、一部が前記測定対象物の一端において反射され、第１干渉手段へと戻り第１参照光と重ね合わされ第１測定干渉光となり、その残りは前記測定対象物の脇を通過し前記第２干渉手段へ入射し、第２参照光と重ね合わされ第２基準干渉光となり、
前記第２干渉手段から前記測定対象物の測長軸方向へ反射された光は、一部が前記測定対象物の他端面において反射され、第２干渉手段へと戻り第２参照光と重ね合わされ第２測定干渉光となり、その残りは前記測定対象物の脇を通過し前記第１干渉部へ入射し、第１参照光と重ね合わされ第１基準干渉光となり、
前記第１観察部により、前記第１干渉部で形成される第１基準干渉光と第１測定干渉光とをそれぞれ第１基準干渉縞及び第１測定干渉縞として観察し、
前記第２観察部により、前記第２干渉部で形成される第２基準干渉光と第２測定干渉光とをそれぞれ第２基準干渉縞及び第２測定干渉縞として観察し、
前記第１基準干渉縞と前記第１測定干渉縞との位相差、前記第２基準干渉縞と前記第２測定干渉縞との位相差、および前記測定対象物の予備値に基き、前記測定対象物の光学的寸法を測定する装置であって、該装置を用いた測定によって、前記被測定物と前記基準物との光学的寸法差を求めることが好適である。 In the above-described phase correction value measuring method, the non-contact light wave interference measuring apparatus divides the light irradiated from the light irradiating means having a predetermined beam diameter and wavelength, and the light irradiated from the light irradiating means into two light beams. A first observation for observing the light splitting means, the first interference means and the second interference means having an optical axis coinciding with the measurement axis of the measurement object, and the interference fringes of the first interference means and the second interference means, respectively. Means and second observation means,
One of the two light beams divided by the light splitting unit is incident on the first interference unit, a part of the light beam becomes the first reference light, and the rest of the beam is measured by the first interference unit. Reflected in the measuring axis direction,
The other light beam of the two light beams split by the light splitting unit is incident on the second interference unit, a part of the beam becomes second reference light, and the rest of the beam is measured by the second interference unit. Reflected in the measuring axis direction,
A part of the light reflected from the first interference means in the measuring axis direction of the measurement object is reflected at one end of the measurement object, returns to the first interference means, and overlaps with the first reference light. 1 measurement interference light, the remainder passes by the side of the measurement object, enters the second interference means, and is superimposed on the second reference light to become the second reference interference light,
A part of the light reflected from the second interference means in the measuring axis direction of the measurement object is reflected on the other end surface of the measurement object, returns to the second interference means, and is superimposed on the second reference light. It becomes the second measurement interference light, the remainder passes by the side of the measurement object, enters the first interference part, is superposed on the first reference light and becomes the first reference interference light,
The first observation unit observes the first reference interference light and the first measurement interference light formed by the first interference unit as a first reference interference fringe and a first measurement interference fringe, respectively.
The second observation unit observes the second reference interference light and the second measurement interference light formed by the second interference unit as a second reference interference pattern and a second measurement interference pattern, respectively.
The measurement object based on a phase difference between the first reference interference fringe and the first measurement interference fringe, a phase difference between the second reference interference fringe and the second measurement interference fringe, and a preliminary value of the measurement object It is an apparatus for measuring the optical dimension of an object, and it is preferable that an optical dimension difference between the object to be measured and the reference object is obtained by measurement using the apparatus.

また、上記の位相補正値測定方法において、前記接触式比較測定は、測定する端面に接触させる接触子と、該接触子の非接触側に設置された鏡面と、を備えた治具を使用し、測定対象物の相対向する端面に前記接触子をそれぞれ接触させ、前記鏡面を前記測定対象物の端面に平行になるよう設置し、
前記鏡面を取り付けた測定対象物の両端面へそれぞれ測定光を照射し、該測定対象物の一方の端面の鏡面からの反射光と該反射光に可干渉な参照光との干渉光と、前記測定対象物の他方の端面の鏡面からの反射光と該反射光に可干渉な参照光との干渉光と、に基づいて前記鏡面間の光学的寸法を測定し該鏡面間の光学的寸法から測定対象物の機械的寸法を求める測長装置を用い、前記被測定物と前記基準物の機械的寸法差を測定することが好適である。
上記の位相補正値測定方法において、前記基準物は光学的定数による位相変化を実質的に起こさない複素屈折率を持つ材質で形成され、該基準物の測定光が照射される面の表面粗さが測定に用いる光の波長より小さいことが好適である。 In the phase correction value measuring method, the contact-type comparative measurement uses a jig including a contactor that is in contact with an end face to be measured and a mirror surface that is installed on a non-contact side of the contactor. , The contactors are brought into contact with the opposite end surfaces of the measurement object, and the mirror surface is installed so as to be parallel to the end surface of the measurement object,
Irradiating measurement light to both end surfaces of the measurement object to which the mirror surface is attached, and interference light between reflected light from the mirror surface of one end surface of the measurement object and reference light that is coherent with the reflected light, and The optical dimension between the mirror surfaces is measured based on the reflected light from the mirror surface of the other end surface of the object to be measured and the interference light of the reference light that is coherent with the reflected light, and from the optical dimension between the mirror surfaces. It is preferable to measure a mechanical dimension difference between the object to be measured and the reference object by using a length measuring device for obtaining a mechanical dimension of the object to be measured.
In the phase correction value measuring method, the reference object is formed of a material having a complex refractive index that does not substantially cause a phase change due to an optical constant, and the surface roughness of the surface irradiated with the measurement light of the reference object Is preferably smaller than the wavelength of light used for measurement.

本発明の位相補正値測定方法によれば、非密着光波干渉測定による光学的な寸法差と、接触式比較測定による機械的な寸法差とから位相補正値を求めているため、リンギングという熟練を要する作業が不要であり、簡単、効率的かつ高精度に位相補正値を測定することが可能となった。その結果、位相補正値の精度が向上し、端度器等の校正の不確かさを低減することができる。   According to the phase correction value measuring method of the present invention, the phase correction value is obtained from the optical dimensional difference by the non-contact optical interference measurement and the mechanical dimensional difference by the contact-type comparative measurement. The necessary work is unnecessary, and the phase correction value can be measured easily, efficiently and with high accuracy. As a result, the accuracy of the phase correction value can be improved, and the uncertainty of calibration of the edge scale can be reduced.

以下に本発明の好適な実施形態について説明を行う。
本発明の一実施形態に係る位相補正値測定方法は、位相補正値が未知の端度器等の被測定物と位相補正値が既知の基準物とを用意する工程と、前記被測定物の光学的寸法と前記基準物の光学的寸法との光学的寸法差を非密着光波干渉測定により測定する工程と、前記被測定物と前記基準物との機械的寸法差と接触式比較測定によって測定する工程と、を含む。そして、測定した光学的寸法差と機械的寸法差とに基づいて被測定物の位相補正値が算出される。
本実施形態では光学的寸法差を測定するときの光波干渉測定装置は、測定する両端面側から光を照射して非密着で寸法測定を行うものを使用する（図３参照）。例えば特許文献２、３に記載された装置を用いることができる。 Hereinafter, preferred embodiments of the present invention will be described.
A phase correction value measurement method according to an embodiment of the present invention includes a step of preparing a measurement object such as a protractor whose phase correction value is unknown and a reference object whose phase correction value is known; A step of measuring an optical dimension difference between an optical dimension and an optical dimension of the reference object by non-contact optical interference measurement, and a mechanical dimension difference between the object to be measured and the reference object and a contact type comparative measurement. And a step of performing. Then, the phase correction value of the object to be measured is calculated based on the measured optical dimensional difference and mechanical dimensional difference.
In the present embodiment, a light wave interference measuring apparatus for measuring an optical dimensional difference is one that measures light in a non-contact manner by irradiating light from both end faces to be measured (see FIG. 3). For example, the apparatuses described in Patent Documents 2 and 3 can be used.

本実施形態では、被測定物と基準物として、位相補正値を測定したい材質のブロックゲージＸ（被測定物）と、それと同じ呼び寸法の基準ブロックゲージＳ（基準物）を用意する。これを図１に示すように、非密着光波干渉測定によって光学的な寸法測定を行う。このときのブロックゲージＸの光波干渉測定結果をＬＩＸ、測定面の片側で発生する位相変化分をＣＸとすると、ブロックゲージＸの端面間の機械的寸法ＬＸは、
ＬＸ＝ＬＩＸ＋２ＣＸ …（式１）
となる。ここで、非密着式の光波干渉測定では、測定光は測定対象物の両側の面で反射するため、片側の位相変化分の２倍が位相補正値となる。 In the present embodiment, as a measurement object and a reference object, a block gauge X (measurement object) of a material whose phase correction value is to be measured and a reference block gauge S (reference object) having the same nominal size are prepared. As shown in FIG. 1, optical dimension measurement is performed by non-contact optical interference measurement. If the optical interference measurement result of the block gauge X at this time is L IX and the phase change generated on one side of the measurement surface is C X , the mechanical dimension L X between the end surfaces of the block gauge X is
L X = L IX + 2C X (Formula 1)
It becomes. Here, in the non-contact type light wave interference measurement, since the measurement light is reflected on both surfaces of the measurement object, twice the phase change on one side becomes the phase correction value.

また、同様に基準ブロックゲージＳは、光学的寸法をＬＩＳ、測定面片側で発生する位相変化分をＣＳとすると、端面間の機械的寸法ＬＳは、
ＬＳ＝ＬＩＳ＋２ＣＳ …（式２）
となる。
次に図２に示すように被測定ブロックゲージと基準ブロックゲージとを接触式の測長装置を用いて機械的寸法差を比較測定する。これにより測定される端面間の寸法の差ΔＬは
ΔＬ＝ＬＸ−ＬＳ …（式３）
となる。接触式の比較測定器では接触子をブロックゲージの端面に接触させて測定を行うため、測定される寸法は端面の粗さ曲線の最上部を測定位置としたものが得られる。また、機械寸法差を、基準物との比較による比較測定によって求めているため、誤差の少ない非常に高精度な値が得られる。 Similarly, the reference gauge block S is an optical dimension L IS, when the phase variation generated in the measurement surface side and C S, the mechanical dimensions L S between the end faces,
L S = L IS + 2C S (Formula 2)
It becomes.
Next, as shown in FIG. 2, the measured block gauge and the reference block gauge are compared and measured using a contact-type length measuring device. The dimension difference ΔL between the end faces measured in this way is ΔL = L X −L S (Equation 3)
It becomes. In the contact-type comparative measuring instrument, the contact is brought into contact with the end face of the block gauge and the measurement is performed. Therefore, the measured dimension is obtained with the uppermost portion of the roughness curve of the end face as the measurement position. In addition, since the machine dimensional difference is obtained by comparative measurement by comparison with a reference object, a highly accurate value with little error can be obtained.

そこで（式３）に（式１），（式２）を代入すると、
ΔＬ＝ＬＩＸ−ＬＩＳ＋２ＣＸ−２ＣＳ
これをＣＸについて解くと、
ＣＸ＝ＣＳ＋（ＬＩＳ−ＬＩＸ＋ΔＬ）／２ …（式４）
となる。これにより、基準ブロックゲージＳの位相変化分ＣＳが既知であれば（式４）によりブロックゲージＸの測定面片側で発生する位相変化分ＣＸが求められ、これが位相補正値となる。つまり、被密着光波干渉測定器によって寸法を測定した場合には、その光学的寸法値に上記の位相変化分ＣＸの２倍を加えることによって実際の寸法値を求めることができる。また、密着式の光波干渉測定によって測定した場合は、測定光が照射されるのはブロックゲージの一方の面だけであるので、上記の位相変化分ＣＸを加えることで実際の寸法が得られる。 Therefore, if (Equation 1) and (Equation 2) are substituted into (Equation 3),
ΔL = L IX -L IS + 2C X -2C S
Solving this for CX ,
C X = C S + ( LIS− L IX + ΔL) / 2 (Formula 4)
It becomes. Thereby, if the phase change C S of the reference block gauge S is known, the phase change C X generated on one side of the measurement surface of the block gauge X is obtained by (Equation 4), and this is the phase correction value. That is, when the dimension is measured by the light wave interference measuring instrument, the actual dimension value can be obtained by adding twice the phase change CX to the optical dimension value. Further, when measured by contact-type light wave interference measurement, the measurement light is irradiated only on one surface of the block gauge, so that the actual dimensions can be obtained by adding the above-described phase change CX. .

このように位相補正値が既知の基準物を用意して、寸法差を基準物との比較測定によって求めているため、非常に高精度に位相補正値を求めることが可能であり、また、非密着の光波干渉測定によって光学的寸法を測定しているため、リンギングの必要がなく、容易に高精度な測定を行うことができる。つまり、本発明は、接触式比較測定と非接触式の光波干渉測定による両測定結果を用いることで、高精度な位相補正値測定を可能としたものである。   In this way, a reference object with a known phase correction value is prepared, and the dimensional difference is obtained by comparison measurement with the reference object. Therefore, it is possible to obtain the phase correction value with very high accuracy. Since the optical dimensions are measured by close-contact optical interference measurement, ringing is not necessary, and high-accuracy measurement can be easily performed. That is, the present invention enables highly accurate phase correction value measurement by using both measurement results of contact-type comparative measurement and non-contact-type light wave interference measurement.

また、上記光学的寸法差を測定する際には、被測定物と基準物とを別々に測定しても、被測定物と基準物を並列に並べて同時に測定を行ってもよい。
また、基準物として光学的定数による反射時の位相変化を起こさない複素屈折率をもつ材質を用いることが好適である。つまり、材質の複素屈折率の虚数部分（吸収係数）が実質的に０（そのときに要求される測定精度で無視し得る程度）であればよい。具体的には、どの程度の測定精度を要求するかで異なってくるが、複素屈折率の虚数部分が０．１以下、さらに好適には０．０４以下であれば十分である。 Further, when measuring the optical dimensional difference, the measurement object and the reference object may be measured separately, or the measurement object and the reference object may be arranged in parallel and simultaneously measured.
Further, it is preferable to use a material having a complex refractive index that does not cause a phase change at the time of reflection due to an optical constant as a reference object. That is, it is only necessary that the imaginary part (absorption coefficient) of the complex refractive index of the material is substantially 0 (to the extent that the measurement accuracy required at that time can be ignored). Specifically, it depends on how much measurement accuracy is required, but it is sufficient if the imaginary part of the complex refractive index is 0.1 or less, more preferably 0.04 or less.

さらに、表面粗さとしては測定に用いる光の波長より小さくなるよう加工されたものを基準物として用いることが好適である。つまり、表面粗さも要求される測定精度に応じた基準以下であればよい。具体的には、要求される測定精度によって異なってくるが、粗さ曲線の最大山高さＲｐで、おおよそ１０ｎｍ以下、さらに好適には一桁前半ｎｍ以下であれば、高精度な測定でも形状補正値を０とみなせる。
これらの条件を満たすものとして、例えば、合成石英、硼珪酸ガラス、等の光学ガラス素材等がある。これらの材質を基準物Ｓとするとその位相補正値ＣＳは０とみなすことができる。 Furthermore, as the surface roughness, it is preferable to use the surface roughness processed so as to be smaller than the wavelength of light used for measurement. That is, the surface roughness may be equal to or less than the standard corresponding to the required measurement accuracy. Specifically, although it depends on the required measurement accuracy, if the maximum peak height Rp of the roughness curve is approximately 10 nm or less, and more preferably less than the first half of an order of magnitude, the shape correction can be performed even with high accuracy measurement. The value can be regarded as 0.
As a material satisfying these conditions, for example, there are optical glass materials such as synthetic quartz and borosilicate glass. When these materials as a reference object S is the phase correction value C S can be regarded as zero.

以上が本実施形態の位相補正値測定方法の概略である。次に個々の寸法差測定の工程について説明する。図２は接触式比較測定器の一実施形態例の概略構成図である。
図２の接触式比較測定器２１０は、変位計２１２、２１４が測定対象物の両測定面側で支持された構成となっている。つまり、被測定物（位相補正値を測定するブロックゲージ（ＧＢ））、及び基準物（基準ブロックゲージ（ＧＢ））は、測長軸を鉛直にして支持台２１８上に置かれる。そして、支持柱２１６によって支持された変位計２１２が測定対象物の上部測定面側に設置され、変位計２１４は支持台２１８の下に置かれ、測定対象物の下部測定面側に設置される。変位計２１４の接触子２２２は、支持台２１８面にある穴を通して、測定対象物の下部測定面にその先端を接触できるようになっている。また、変位計２１２の接触子２２０は測定対象物の上部測定面に接触できるようになっている。２つの変位計２１２、２１４からの変位量の情報は比較器２２４へと送られ、二つの測定対象物の機械的な寸法差を得ることができる。 The above is the outline of the phase correction value measurement method of the present embodiment. Next, individual dimensional difference measurement steps will be described. FIG. 2 is a schematic configuration diagram of an embodiment of a contact-type comparative measuring instrument.
2 has a configuration in which displacement gauges 212 and 214 are supported on both measurement surface sides of the measurement object. That is, the device under test (block gauge (GB) for measuring the phase correction value) and the reference object (reference block gauge (GB)) are placed on the support base 218 with the length measurement axis vertical. The displacement meter 212 which is supported by the support post 216 is installed on the upper measurement surface of the measurement object, the displacement meter 214 is placed under the support base 21 8 is installed in the lower measurement surface of the measurement object The Contact 222 of the displacement gauge 214, through a hole in the support table 21 8 side, and to be able to contact the front end to the lower measurement surface of the measurement object. Further, the contact 220 of the displacement meter 212 can come into contact with the upper measurement surface of the measurement object. Information on the displacement amounts from the two displacement meters 212 and 214 is sent to the comparator 224, and a mechanical dimensional difference between the two measurement objects can be obtained.

寸法差の測定は次のようにして行う。まず、基準ＧＢを支持台２１８面にある穴の上に測長軸を鉛直方向にして設置する。次に変位計２１２、２１４の接触子２２０、２２２を基準ＧＢの上下の両端面に所定の測定力で接触させ、このときのそれぞれの変位計の値を原点とする。次に位相補正値を測定するＧＢを支持台２１８面にある穴の上に、測長軸を鉛直方向にして設置する。そして、変位計２１２、２１４の接触子２２０、２２２を測定対象のＧＢの上下両端面に接触させる。変位計２１２、２１４の変位量は比較器２２４に送られ、先にセットした原点からの変位量が計測される。こうして求めた変位計２１２、２１４の変位量から、基準ＧＢと測定対象のＧＢとの機械的寸法差が求められる。また、上記の接触子が測定物に与える測定力は測定物の変形が無視できるように十分小さくする必要がある。測定力の大きさは測定物の材質等を考慮して決めればよい。 The dimensional difference is measured as follows. First, placed by the measurement axis in the vertical direction on the hole in the reference GB support base 21 8 surface. Next, the contacts 220 and 222 of the displacement meters 212 and 214 are brought into contact with the upper and lower end surfaces of the reference GB with a predetermined measuring force, and the values of the respective displacement meters at this time are set as the origins. Then on the hole in the GB measuring the phase correction value to the support table 21 eight surfaces, placed in a measurement axis in the vertical direction. Then, the contacts 220 and 222 of the displacement meters 212 and 214 are brought into contact with the upper and lower end surfaces of the GB to be measured. The displacement amounts of the displacement meters 212 and 214 are sent to the comparator 224, and the displacement amount from the previously set origin is measured. A mechanical dimensional difference between the reference GB and the GB to be measured is obtained from the displacement amounts of the displacement meters 212 and 214 thus obtained. Further, the measuring force applied to the measurement object by the above-described contact must be sufficiently small so that the deformation of the measurement object can be ignored. The magnitude of the measurement force may be determined in consideration of the material of the measurement object.

このように接触式比較測定器は、接触部の接触子が測定物の表面の直接接触し、かつ接触子の直径が測定物の表面粗さに比べ十分に大きいので、粗さ曲線の最上部を測定位置とする測定が簡単に実現できる。また、一般に比較測定器は測定レンジを狭い範囲に絞ることによって高精度の測定を行うことができる。そこで、測定の再現性だけに限定すれば、リンギングによる光波干渉測定よりも高い再現性が得られるため、容易に高精度な比較測定が可能である。
光波干渉測定装置を所有するような研究室、校正室には、事前に測定光の波長の２分の１以内の精度で予備測定を行うための装置として接触式の測定器が必要である。そのため、特別準備が必要な装置ではない。
図２では変位計を２つ用いる２点測定法による比較測定器を説明したが、変位計を一つしか持たない１点測定法による比較測長器を用いてもよい。 In this way, the contact-type comparative measuring device has a contact portion in direct contact with the surface of the object to be measured and the diameter of the contact is sufficiently larger than the surface roughness of the object to be measured. Measurement with the measurement position can be easily realized. In general, a comparative measuring instrument can perform highly accurate measurement by narrowing the measurement range to a narrow range. Therefore, if only the reproducibility of the measurement is limited, a higher reproducibility can be obtained than the light wave interference measurement by ringing, and therefore, a highly accurate comparative measurement can be easily performed.
In laboratories and calibration rooms that own optical wave interference measuring devices, a contact-type measuring device is required as a device for performing preliminary measurement with accuracy within a half of the wavelength of the measuring light in advance. Therefore, it is not a device that requires special preparation.
In FIG. 2, a comparative measuring instrument using a two-point measuring method using two displacement meters has been described, but a comparative measuring instrument using a one-point measuring method having only one displacement meter may be used.

次に非密着光波干渉測定装置の説明を行う。図３は光波干渉測定装置の一実施形態例の概略構成図である。図３の光波干渉測定装置３１０は光照射手段３１２と、照射された光を分割する第１ハーフミラー３１４(光分割手段)と、所定の距離だけ離間して配置された第２ハーフミラー３１６(第１干渉手段)及び第３ハーフミラー３１８(第２干渉手段)と、第２、３ハーフミラー３１６、３１８にそれぞれ対応した第１参照鏡３２０(第１干渉手段)、第２参照鏡３２２(第２干渉手段)と、第１スクリーン３２４(第１観察手段)、第２スクリーン３２６(第２観察手段)と、を備えている。第２ハーフミラー３１６と第３ハーフミラー３１８とは、それらを結ぶ測定光の光軸が測定対象物３２８の測長軸と一致するように配置される。また、第１スクリーン３２４、第２スクリーン３２６はそれぞれ第２，３ハーフミラー３１６、３１８の後段に設置されており、ここで干渉縞が形成される。光照射手段３１２は光源３３０、コリメータレンズ３３２、反射鏡３３４等を含み、所定のビーム径及び波長を持つレーザ光を照射する。レーザ光は被測定物３２８の端面で反射されるものと測定対象物の脇を通り抜けていくものが必要なため、レーザ光のビーム径はある程度の大きさを持つことが必要である。このため測定対象物の断面積より大きいビーム径であることが望ましい。   Next, the non-contact light wave interference measuring apparatus will be described. FIG. 3 is a schematic configuration diagram of an embodiment of the optical interference measurement apparatus. 3 includes a light irradiation unit 312, a first half mirror 314 (light division unit) that divides the emitted light, and a second half mirror 316 (a light separation unit) that is spaced apart by a predetermined distance. First interference means) and third half mirror 318 (second interference means), first reference mirror 320 (first interference means) and second reference mirror 322 corresponding to the second and third half mirrors 316 and 318, respectively. Second interference means), a first screen 324 (first observation means), and a second screen 326 (second observation means). The second half mirror 316 and the third half mirror 318 are arranged so that the optical axis of the measurement light connecting them coincides with the measurement axis of the measurement object 328. In addition, the first screen 324 and the second screen 326 are respectively installed at the subsequent stage of the second and third half mirrors 316 and 318, and interference fringes are formed here. The light irradiation means 312 includes a light source 330, a collimator lens 332, a reflecting mirror 334, and the like, and irradiates laser light having a predetermined beam diameter and wavelength. Since the laser light needs to be reflected by the end face of the object 328 to be measured and to pass through the side of the object to be measured, the beam diameter of the laser light needs to have a certain size. For this reason, it is desirable that the beam diameter is larger than the cross-sectional area of the measurement object.

また、第１参照鏡３２０と第２ハーフミラー３１６との組、第２参照鏡３２２と第３ハーフミラー３１８との組は測定光と参照光を干渉させる干渉手段として働く。そして、第１ハーフミラー３１４と第２ハーフミラー３１６と第３ハーフミラー３１８とによって、環状の干渉計が構成されている。
光照射手段３１２から照射されたレーザ光は第１ハーフミラー３１４により二光束に分割され、それぞれ第２ハーフミラー３１６、第３ハーフミラー３１８へと向かう。この第２ハーフミラー３１６に入射した光は測長軸方向へ反射する光と、第２ハーフミラー３１６を透過し第１参照鏡３２０に向かう光とに分割される。第１参照鏡３２０に向かった光はそこで反射され、第２ハーフミラー３１６へと戻り、この光が第１参照光となる。また、測長軸方向へ向かった光の一部は測定対象物３２８の図中左端面３２８ａで反射し第２ハーフミラー３１６へ戻り、その残りは測定対象物３２８の脇を通り抜け第３ハーフミラー３１８へと向かう。 Further, the set of the first reference mirror 320 and the second half mirror 316 and the set of the second reference mirror 322 and the third half mirror 318 function as interference means for causing the measurement light and the reference light to interfere with each other. The first half mirror 314, the second half mirror 316, and the third half mirror 318 constitute an annular interferometer.
The laser light emitted from the light irradiation means 312 is divided into two light fluxes by the first half mirror 314 and directed to the second half mirror 316 and the third half mirror 318, respectively. The light incident on the second half mirror 316 is divided into light that is reflected in the length measuring axis direction and light that passes through the second half mirror 316 and travels toward the first reference mirror 320. The light directed to the first reference mirror 320 is reflected there, returns to the second half mirror 316, and this light becomes the first reference light. Further, part of the light traveling in the direction of the measuring axis is reflected by the left end surface 328a of the measurement object 328 in the drawing and returns to the second half mirror 316, and the rest passes by the measurement object 328 and passes through the third half mirror. Head to 318.

同様に、第１ハーフミラー３１４で分割された二光束のうち第３ハーフミラー３１８に入射した光は、測長軸方向へ反射する光と、第３ハーフミラー３１８を透過し第２参照鏡３２２に向かう光とに分割される。その第２参照鏡３２２に向かった光はそこで反射され、第３ハーフミラー３１８へと戻り、第２参照光となる。また、測長軸方向へ向かった光の一部は測定対象物３２８の図中右端面３２８ｂで反射し第３ハーフミラー３１８へ戻り、その残りは測定対象物３２８の脇を通り抜け第２ハーフミラー３１６へ向かう。
以上のような光路を辿った光は、第２ハーフミラー３１６において、第１参照鏡３２０からくる第１参照光と、測定対象物３２８の脇を通過してきた光とが干渉して第１基準干渉光となり、また測定対象物３２８の左端面３２８ａで反射された光と前記第１参照光とが干渉し第１測定干渉光となる。これらの干渉光は第１スクリーン３２４に向かい、そこで干渉縞として観察され、第１基準干渉縞と第１測定干渉縞の位相差が読み取られる。 Similarly, of the two light beams divided by the first half mirror 314, the light incident on the third half mirror 318 is transmitted through the third half mirror 318 and the second reference mirror 322 through the third half mirror 318 and the light reflected in the measurement axis direction. It is divided into the light which goes to. The light directed to the second reference mirror 322 is reflected there, returns to the third half mirror 318, and becomes the second reference light. Further, a part of the light traveling in the length measuring axis direction is reflected by the right end surface 328b of the measurement object 328 in the drawing and returns to the third half mirror 318, and the rest passes through the measurement object 328 and passes through the second half mirror. Head to 316.
In the second half mirror 316, the light that has traveled the optical path as described above interferes with the first reference light coming from the first reference mirror 320 and the light that has passed by the side of the measurement object 328, so that the first reference The light becomes interference light, and the light reflected by the left end surface 328a of the measurement object 328 interferes with the first reference light to become the first measurement interference light. These interference lights travel to the first screen 324, where they are observed as interference fringes, and the phase difference between the first reference interference fringes and the first measurement interference fringes is read.

同様にして、第３ハーフミラー３１８では、測定対象物３２８の脇を通過してきた光と第２参照鏡３２２からの第２参照光とが干渉して第２基準干渉光となり、測定対象物３２８の右端面３２８ｂで反射された光と、第２参照鏡３２２からの第２参照光とが干渉して第２測定干渉光となる。また、これらの干渉光は、第２スクリーン３２６でそれぞれ第２基準干渉縞、第２測定干渉縞として観測され、基準干渉縞と測定干渉縞との位相差が読み取られる。
以上のようにして、第１スクリーン３２４と第２スクリーン３６でそれぞれ観察される第１基準干渉縞と第１測定干渉縞との位相差、第２基準干渉縞と第２測定干渉縞との位相差と、測定対象物の予備値と、をもとにして、測定対象物の光学的寸法ＬＢが測定される。 Similarly, in the third half mirror 318, the light that has passed by the side of the measurement object 328 interferes with the second reference light from the second reference mirror 322 to become the second reference interference light, and the measurement object 328 is obtained. The light reflected by the right end surface 328b of the second reference mirror 322 interferes with the second reference light from the second reference mirror 322 to become second measurement interference light. These interference lights are observed as the second reference interference fringe and the second measurement interference fringe on the second screen 326, respectively, and the phase difference between the reference interference fringe and the measurement interference fringe is read.
As described above, the phase difference between the first reference interference fringe and the first measurement interference fringe observed on the first screen 324 and the second screen 36, respectively, and the positions of the second reference interference fringe and the second measurement interference fringe. Based on the phase difference and the preliminary value of the measurement object, the optical dimension L B of the measurement object is measured.

図５（Ａ）は、干渉縞からの位相差の計算の説明図である。図のＧＢは測定対象物の端面を、図の円で囲んだ部分は測定光束をそれぞれ模式的に示したものである。測定対象物の両脇の点での基準干渉縞（図示せず）から求まる位相ΦＡ、ΦＣの平均値と、測定対象物の端面上の点での測定干渉縞（図示せず）から求まる位相ΦＢとの差を計算することで、基準干渉縞と測定干渉縞との位相差を求めることができる。 FIG. 5A is an explanatory diagram of the calculation of the phase difference from the interference fringes. GB in the figure schematically shows the end face of the measurement object, and the portion surrounded by a circle in the figure schematically shows the measurement light beam. From average values of phases Φ A and Φ C obtained from reference interference fringes (not shown) at both sides of the measurement object and measurement interference fringes (not shown) at points on the end face of the measurement object by calculating the difference between the obtained phase [Phi B, it is possible to obtain the phase difference between the reference interference fringe and the measured interference fringe.

上記で求めた干渉縞の位相差からの寸法の算出について、図１を参照して説明する。第１ハーフミラー３１４から第２ハーフミラー３１６へ、さらに被測定物３２８の図中左端面３２８ａで反射し、再び第２ハーフミラー３１６へと戻る光路の光路長をＬ１とする。また、第１ハーフミラー３１４から第３ハーフミラー３１８に向かい、そこで反射され被測定物３２８の脇を通り抜け第２ハーフミラー３１６へ入射するまでの光路長をＬ２とする。同様に、光路長Ｌ３は第１ハーフミラー３１４、第３ハーフミラー３１８、被測定物４２の右端面３２８ｂ、第３ハーフミラー３１８へと進む光路長とする。光路長Ｌ４は、第１ハーフミラー３１４から第２ハーフミラー３１６へと向かい、そこで反射され被測定物３２８の脇を通過し第３ハーフミラー３１８へ入射するまでの光路長とする。 Calculation of the dimension from the phase difference of the interference fringes obtained above will be described with reference to FIG. From the first half mirror 314 to the second half mirror 316, further reflected by the left end in the drawing surface 328a of the workpiece 328, the optical path length of the optical path and L 1 back to the second half mirror 316 again. Further, from the first half mirror 314 toward the third half mirror 318, where the optical path length to be reflected to enter the second half mirror 316 through the side of the object to be measured 328 and L 2. Similarly, the optical path length L 3 is an optical path length that travels to the first half mirror 314, the third half mirror 318, the right end surface 328 b of the DUT 42, and the third half mirror 318. The optical path length L 4 is an optical path length from the first half mirror 314 to the second half mirror 316, reflected there, passing through the side of the measured object 328, and entering the third half mirror 318.

すると測定対象物の寸法ＬＢは上記の光路長Ｌ１，Ｌ２，Ｌ３，Ｌ４を用いて次の式で表される。
ＬＢ＝１／２｛（Ｌ４−Ｌ３）＋（Ｌ２−Ｌ１）｝ …（式５）
また、上記の光路長Ｌ１、Ｌ２、Ｌ３、Ｌ４を、測定に使用するレーザ光の波長λを用いて表すと以下のようになる。
Ｌｉ＝λ(Ｎｉ＋εｉ) (ｉ＝１〜４) …（式６）
ここで、Ｎｉは光路長Ｌｉを波長λで割った時の商の整数部分、εｉはその商の端数部分(位相)である。(式６)を(式５)に代入すると
ＬＢ＝λ／２｛（Ｎ４−Ｎ３）＋（Ｎ２−Ｎ１）＋（ε４−ε３）＋（ε２−ε１）｝
＝λ／２｛Ｎ＋（ε４−ε３）＋（ε２−ε１）｝ …（式７）
となる。ただし、Ｎ＝（Ｎ４−Ｎ３）＋（Ｎ２−Ｎ１）とした。
上式の（ε２−ε１）が第１スクリーン３２４で観測される第１基準干渉縞と第１測定干渉縞の位相差であり、また、（ε４−ε３）が第２スクリーン３２６で観測される第２基準干渉縞と第２測定干渉縞の位相差である。また、波長λは既知であり、測定対象物の予備値と波長λより算出されるＮを用いて(式７)より測定対象物の寸法ＬＢが求められる。 Then dimension L B of the measurement object by using the above-mentioned optical path length L 1, L 2, L 3 , L 4 is represented by the following formula.
L B = 1/2 {(L 4 −L 3 ) + (L 2 −L 1 )} (Formula 5)
The above optical path lengths L 1 , L 2 , L 3 , and L 4 are expressed as follows using the wavelength λ of the laser light used for measurement.
L i = λ (N i + ε i ) (i = 1 to 4) (Expression 6)
Here, N i is the integer part of the quotient when the optical path length L i is divided by the wavelength λ, and ε i is the fractional part (phase) of the quotient. Substituting (Equation 6) into (Equation 5), L B = λ / 2 {(N 4 −N 3 ) + (N 2 −N 1 ) + (ε 4 −ε 3 ) + (ε 2 −ε 1 ) }
= Λ / 2 {N + (ε 4 −ε 3 ) + (ε 2 −ε 1 )} (Expression 7)
It becomes. However, N = (N 4 −N 3 ) + (N 2 −N 1 ).
(Ε 2 −ε 1 ) in the above equation is the phase difference between the first reference interference fringe and the first measurement interference fringe observed on the first screen 324, and (ε 4 −ε 3 ) is the second screen 326. Is the phase difference between the second reference interference fringe and the second measurement interference fringe observed in FIG. The wavelength λ are known, the dimension L B of the measurement object from using N calculated from the pre-value and the wavelength λ of the measurement object (7) is determined.

また、第１スクリーン３２６の後段には第一読取手段３３６を設けている。そして、第一読取手段３３６は、第一スクリーンで観察された第一基準干渉縞と第一測定干渉縞との位相差（ε２−ε１）を読取り、読取結果はコンピュータ３４０の測定データ記憶部３４４に記憶される。同様に第２スクリーン３２６の後段に第２読取手段３３８を設けられ、第２スクリーン３２６で観察された第２基準干渉縞と第２測定干渉縞との位相差を読取る。その読取結果は同様に測定データ記憶部３４４に記憶される。そして、コンピュータ３４０の演算手段３４２によって、上記位相差情報から測定対象物の光学的寸法を算出する。また、コンピュータ３４０は演算情報記憶部３４６を備え、ブロックゲージ等の測定対象物の予備値の情報や、位相差から寸法を算出するためのプログラム等が予め記憶されている。 A first reading unit 336 is provided at the subsequent stage of the first screen 326. The first reading unit 336 reads the phase difference (ε 2 −ε 1 ) between the first reference interference fringe and the first measurement interference fringe observed on the first screen, and the reading result is stored in the measurement data of the computer 340. Stored in the unit 344. Similarly, a second reading unit 338 is provided at the subsequent stage of the second screen 326 to read the phase difference between the second reference interference fringe and the second measurement interference fringe observed on the second screen 326. The read result is similarly stored in the measurement data storage unit 344. Then, the optical means of the measurement object is calculated from the phase difference information by the computing means 342 of the computer 340. In addition, the computer 340 includes a calculation information storage unit 346, and preliminarily stores information on a preliminary value of a measurement object such as a block gauge, a program for calculating a dimension from a phase difference, and the like.

上記のように構成された非密着光波測定装置を用い、位相補正値が未知の被測定物に対して上記の測定を行いその光学的寸法を測定する。また同様に位相補正値が既知の基準物に対しても同様の測定を行い光学的寸法を測定する。そして、それぞれの測定結果から、被測定物と基準物との光学的寸法差が求められる。
また、光学的寸法を測定する際には、被測定物の光学的寸法と基準物の光学的寸法を順番に別々に測定してもよいし、被測定物と基準物を並列に並べて同時に測定を行ってもよい。つまり、第２ハーフミラー３１６及び第３ハーフミラー３１８からの光が、被測定物の両端面、基準物の両端面のどちらにも照射されるように、被測定物と基準物を並列に並べて設置する。また、被測定物と基準物の間にも光が通過するように被測定物と基準物を離して配置する。図５（Ｂ）を参照して、並列に並べたときの位相差の計算を説明する。図中の二つの四角は被測定物（図のＧＢ１）の端面及び基準物（ＧＢ２）の端面を、円は測定光束の部分を模式的に示している。干渉縞（図示せず）からの位相差の計算は、測定対象が一つの場合（図５（Ａ）の場合）と同様に行えばよい。つまり、ＧＢ１の両脇の点での位相ΦＡ、ΦＣの平均値とＧＢ１の端面の点での位相ΦＢとの差によって、ＧＢ１における基準干渉縞と測定干渉縞との位相差を求める。また、同様にしてＧＢ２の両脇の点での位相ΦＣ、ΦＥの平均値とＧＢ２の端面での位相ΦＤとの差によって、ＧＢ２における干渉縞の位相差を求める。これらの位相差からＧＢ１、ＧＢ２のそれぞれの光学的寸法を求めることができ、それらからＧＢ１とＧＢ２との光学的寸法差が算出される。 Using the non-contact light wave measuring apparatus configured as described above, the above-described measurement is performed on an object whose phase correction value is unknown, and its optical dimension is measured. Similarly, the same measurement is performed on a reference object whose phase correction value is known, and the optical dimension is measured. And from each measurement result, the optical dimensional difference of a to-be-measured object and a reference | standard thing is calculated | required.
Also, when measuring the optical dimensions, the optical dimension of the object to be measured and the optical dimension of the reference object may be measured separately in order, or the object to be measured and the reference object are arranged in parallel and measured simultaneously. May be performed. That is, the object to be measured and the reference object are arranged in parallel so that the light from the second half mirror 316 and the third half mirror 318 is irradiated to both the end faces of the object to be measured and both end faces of the reference object. Install. Further, the object to be measured and the reference object are arranged apart so that light can pass between the object to be measured and the reference object. With reference to FIG. 5B, calculation of the phase difference when arranged in parallel will be described. The two squares in the figure schematically show the end face of the object to be measured (GB1 in the figure) and the end face of the reference object (GB2), and the circle schematically shows the portion of the measurement light beam. The calculation of the phase difference from the interference fringes (not shown) may be performed in the same manner as in the case where there is one measurement object (in the case of FIG. 5A). That is, the phase difference between the reference interference fringe and the measurement interference fringe in GB1 is obtained by the difference between the average value of the phases Φ A and Φ C at the points on both sides of GB1 and the phase Φ B at the point on the end face of GB1. . The phase [Phi C in terms of both sides of the GB2 in the same manner, the difference between the phase [Phi D at the end face of the mean and GB2 of [Phi E, obtains the phase difference of the interference fringes in GB2. The optical dimensions of GB1 and GB2 can be obtained from these phase differences, and the optical dimension difference between GB1 and GB2 is calculated from them.

図４は、接触式比較測定の他の実施形態例である。図４には、測定する端面に接触させる接触子４１２、４１４と、該接触子４１２、４１４の非接触側に設置された鏡面４１６、４１８と、上記接触子４１２、４１４を固定する支持部４２０とを備えた治具４１０が示されている。この治具４１０を用い、測定対象物の相対向する端面に前記接触子４１２、４１４をそれぞれ所定の接触力で接触させて固定する。前記接触子４１２、４１４に設けられた鏡面４１６、４１８は、その反射面が測定対象物の端面に平行になるよう設置される。また鏡面を構成する材質は位相補正値が既知の材質であるか、または位相補正値がほとんど０の材質のものを用いる。
このような治具４１０を用い、図３で説明したような非密着光波干渉測定装置を利用して測定対象物の機械的寸法を測定することができる。 FIG. 4 shows another embodiment of the contact type comparative measurement. FIG. 4 shows contacts 412 and 414 brought into contact with the end face to be measured, mirror surfaces 416 and 418 installed on the non-contact side of the contacts 412 and 414, and a support part 420 for fixing the contacts 412 and 414. The jig | tool 410 provided with these is shown. Using the jig 410, the contacts 412 and 414 are brought into contact with the opposing end surfaces of the measurement object with a predetermined contact force and fixed. The mirror surfaces 416 and 418 provided on the contacts 412 and 414 are installed such that their reflection surfaces are parallel to the end surface of the measurement object. The material constituting the mirror surface is a material whose phase correction value is known or a material whose phase correction value is almost zero.
Using such a jig 410, the mechanical dimension of the measurement object can be measured using the non-contact optical interference measuring apparatus as described in FIG.

つまり、上記の治具４１０を位相補正値が未知の被測定物、位相補正値が既知の基準物にそれぞれ取り付ける。治具を取り付けた被測定物、基準物に対して非密着光波干渉装置によって鏡面間の寸法をそれぞれ測定する。つまり、接触子４１２、４１４の非接触側に取り付けた鏡面４１６、４１８がそれぞれ非密着光波測定装置によって照射される測定光が入射する測定面となる。位相補正値が既知の鏡面を用いているため、鏡面間の距離は正確に求めることができる。よって、鏡面間の寸法の測定結果を用い、接触子に挟まれた測定対象物の機械的寸法が測定される。こうして求めた被測定物の機械的寸法と基準物の機械的寸法との差分をとることによって、機械的寸法差を求めることができる。   That is, the jig 410 is attached to an object to be measured whose phase correction value is unknown and a reference object whose phase correction value is known. The dimension between the mirror surfaces is measured by the non-contact light wave interference device with respect to the object to be measured and the reference object to which the jig is attached. That is, the mirror surfaces 416 and 418 attached to the non-contact side of the contacts 412 and 414 become measurement surfaces on which measurement light irradiated by the non-contact light wave measuring device is incident. Since mirror surfaces with known phase correction values are used, the distance between the mirror surfaces can be accurately obtained. Therefore, the mechanical dimension of the measurement object sandwiched between the contacts is measured using the measurement result of the dimension between the mirror surfaces. By taking the difference between the mechanical dimension of the object to be measured thus obtained and the mechanical dimension of the reference object, the mechanical dimension difference can be obtained.

非密着光波干渉測定の説明図Illustration of non-contact optical interference measurement 接触式比較測定器の一実施形態例の説明図Explanatory drawing of one embodiment of a contact type comparative measuring instrument 非密着光波測定器の一実施形態例の概略構成図Schematic configuration diagram of an embodiment of a non-contact light wave measuring device 接触測定のための光波干渉測定用治具の一実施形態の概略構成図Schematic configuration diagram of an embodiment of a light wave interference measurement jig for contact measurement 基準干渉縞と測定干渉縞との位相差の計算の説明図Explanatory drawing of calculation of phase difference between reference interference fringe and measurement interference fringe 表面粗さ、光学定数による反射時の位相変化量の説明図Explanatory diagram of phase change during reflection due to surface roughness and optical constants 従来の位相補正値測定方法の説明図Explanatory drawing of conventional phase correction value measurement method

符号の説明Explanation of symbols

２１０ 接触式比較測定器
３１０ 非接触光波干渉測定装置
４１０ 光波干渉測定用治具 210 Contact-type comparative measuring device 310 Non-contact light wave interference measuring device 410 Light wave interference measuring jig

Claims (4)

光を互いに可干渉な２光束に分け、一方を参照光、他方を測定光とし、測定光を測定対象物に照射し、その反射光と参照光とによる干渉に基づいて前記測定物の相対向する端面間の寸法測定を行う光波干渉測定での測定光の反射時の位相変化分を求める位相補正値測定方法において、
位相変化分ＣＸが未知の被測定物と位相変化分ＣＳが既知の基準物とを用意する工程と、
寸法測定の対象となる測定対象物の相対向する両端面へそれぞれ測定光を照射し、前記測定対象物の一方の端面からの反射光と参照光との干渉と、前記測定対象物の他方の端面からの反射光と参照光との干渉と、に基づいて前記測定対象物の光学的寸法を測定する非密着光波干渉測定装置を用いて、前記被測定物の光学的寸法ＬＩＸと前記基準物の光学的寸法ＬＩＳとの差である光学的寸法差ΔＬ Ｉ （ΔＬ Ｉ ＝ＬＩＸ −ＬＩＳ ）を求める工程と、
寸法測定の対象となる測定対象物の端面に接触子を接触させ、該接触子の接触位置に基づいて前記測定対象物の相対向する端面間の機械的寸法を測定する接触式の測長装置を用い、前記被測定物の機械的寸法Ｌ Ｘ と前記基準物の機械的寸法Ｌ Ｓ との差である機械的寸法差ΔＬ（ΔＬ＝Ｌ Ｘ −Ｌ Ｓ ）を接触式比較測定によって求める工程と、
前記光学的寸法差ΔＬ Ｉ 、前記機械的寸法差ΔＬ、及び前記基準物の位相変化量ＣＳから前記被測定物の位相変化分ＣＸを次の式、
ＣＸ＝ＣＳ ＋ΔＬ／２−ΔＬ Ｉ ／２
によって求める工程と、
を含むことを特徴とする位相補正値測定方法。 The light is divided into two coherent light beams, one is the reference light, the other is the measurement light, the measurement light is irradiated to the measurement object, and the measurement object is opposed to each other based on the interference between the reflected light and the reference light In the phase correction value measurement method for obtaining the phase change amount at the time of reflection of the measurement light in the light wave interference measurement for measuring the dimension between the end faces,
Preparing a measurement object whose phase change C X is unknown and a reference object whose phase change C S is known;
Irradiate measurement light to both opposite end surfaces of the measurement object to be dimensioned, interference between the reflected light from one end surface of the measurement object and the reference light, and the other of the measurement object Using a non-contact optical interference measuring apparatus that measures the optical dimension of the measurement object based on the interference between the reflected light from the end surface and the reference light, the optical dimension L IX of the object to be measured and the reference Determining an optical dimension difference ΔL I (ΔL I = L I X −L I S ) which is a difference from the optical dimension L IS of the object;
A contact-type length measuring device that contacts a contact surface with an end surface of a measurement object to be dimensioned and measures a mechanical dimension between opposing end surfaces of the measurement object based on a contact position of the contact device. And obtaining a mechanical dimension difference ΔL (ΔL = L X −L S ) , which is a difference between the mechanical dimension L X of the object to be measured and the mechanical dimension L S of the reference object, by contact-type comparative measurement When,
Said optical dimensional difference [Delta] L I, the mechanical dimensions difference [Delta] L, and the phase change amount C X the following equation of the object to be measured from the phase variation amount C S of the reference object,
C X = C S + ΔL / 2 -ΔL I / 2
The process sought by
A phase correction value measuring method comprising: 請求項１の位相補正値測定方法において、
前記非密着光波干渉測定装置は、所定のビーム径及び波長を持つ光を照射する光照射手段と、前記光照射手段から照射された光を二光束に分割する光分割手段と、測定対象物の測長軸と一致する光軸を有する第１干渉手段及び第２干渉手段と、前記第１干渉手段及び第２干渉手段の干渉縞をそれぞれ観察する第１観察手段と第２観察手段と、を備え、
前記光分割手段により分割された二光束の一方の光束は、前記第１干渉手段に入射し、該光束の一部は第１参照光となり、残りは前記第１干渉手段により前記測定対象物の測長軸方向に反射され、
前記光分割手段により分割された二光束の他方の光束は、前記第２干渉手段に入射し、該光束の一部は第２参照光となり、残りは前記第２干渉手段により前記測定対象物の測長軸方向に反射され、
前記第１干渉手段から前記測定対象物の測長軸方向へ反射された光は、一部が前記測定対象物の一端において反射され、第１干渉手段へと戻り第１参照光と重ね合わされ第１測定干渉光となり、その残りは前記測定対象物の脇を通過し前記第２干渉手段へ入射し、第２参照光と重ね合わされ第２基準干渉光となり、
前記第２干渉手段から前記測定対象物の測長軸方向へ反射された光は、一部が前記測定対象物の他端面において反射され、第２干渉手段へと戻り第２参照光と重ね合わされ第２測定干渉光となり、その残りは前記測定対象物の脇を通過し前記第１干渉部へ入射し、第１参照光と重ね合わされ第１基準干渉光となり、
前記第１観察部により、前記第１干渉部で形成される第１基準干渉光と第１測定干渉光とをそれぞれ第１基準干渉縞及び第１測定干渉縞として観察し、
前記第２観察部により、前記第２干渉部で形成される第２基準干渉光と第２測定干渉光とをそれぞれ第２基準干渉縞及び第２測定干渉縞として観察し、
前記第１基準干渉縞と前記第１測定干渉縞との位相差、前記第２基準干渉縞と前記第２測定干渉縞との位相差、および前記測定対象物の予備値に基き、前記測定対象物の光学的寸法を測定する装置であって、該装置を用いた測定によって、前記被測定物と前記基準物との光学的寸法差を求めることを特徴とする位相補正値測定方法。 In the phase correction value measuring method according to claim 1,
The non-contact light wave interference measuring apparatus includes a light irradiating unit that irradiates light having a predetermined beam diameter and wavelength, a light dividing unit that divides light emitted from the light irradiating unit into two light beams, and a measurement object. First interference means and second interference means having optical axes that coincide with the measurement axis, and first observation means and second observation means for observing interference fringes of the first interference means and the second interference means, respectively. Prepared,
One of the two light beams divided by the light splitting unit is incident on the first interference unit, a part of the light beam becomes the first reference light, and the rest of the beam is measured by the first interference unit. Reflected in the measuring axis direction,
The other light beam of the two light beams split by the light splitting unit is incident on the second interference unit, a part of the beam becomes second reference light, and the rest of the beam is measured by the second interference unit. Reflected in the measuring axis direction,
A part of the light reflected from the first interference means in the measuring axis direction of the measurement object is reflected at one end of the measurement object, returns to the first interference means, and overlaps with the first reference light. 1 measurement interference light, the remainder passes by the side of the measurement object, enters the second interference means, and is superimposed on the second reference light to become the second reference interference light,
A part of the light reflected from the second interference means in the measuring axis direction of the measurement object is reflected on the other end surface of the measurement object, returns to the second interference means, and is superimposed on the second reference light. It becomes the second measurement interference light, the remainder passes by the side of the measurement object, enters the first interference part, is superposed on the first reference light and becomes the first reference interference light,
The first observation unit observes the first reference interference light and the first measurement interference light formed by the first interference unit as a first reference interference fringe and a first measurement interference fringe, respectively.
The second observation unit observes the second reference interference light and the second measurement interference light formed by the second interference unit as a second reference interference pattern and a second measurement interference pattern, respectively.
The measurement object based on a phase difference between the first reference interference fringe and the first measurement interference fringe, a phase difference between the second reference interference fringe and the second measurement interference fringe, and a preliminary value of the measurement object An apparatus for measuring an optical dimension of an object, wherein a difference in optical dimension between the object to be measured and the reference object is obtained by measurement using the apparatus. 請求項１または２に記載の位相補正値測定方法において、
前記接触式比較測定は、測定する端面に接触させる接触子と、該接触子の非接触側に設置された鏡面と、を備えた治具を使用し、測定対象物の相対向する端面に前記接触子をそれぞれ接触させ、前記鏡面を前記測定対象物の端面に平行になるよう設置し、
前記鏡面を取り付けた測定対象物の両端面へそれぞれ測定光を照射し、該測定対象物の一方の端面の鏡面からの反射光と該反射光に可干渉な参照光との干渉光と、前記測定対象物の他方の端面の鏡面からの反射光と該反射光に可干渉な参照光との干渉光と、に基づいて前記鏡面間の光学的寸法を測定し該鏡面間の光学的寸法から測定対象物の機械的寸法を求める測長装置を用い、前記被測定物と前記基準物の機械的寸法差を測定することを特徴とする位相補正値測定方法。 In the phase correction value measuring method according to claim 1 or 2,
The contact-type comparative measurement uses a jig provided with a contactor to be brought into contact with an end surface to be measured and a mirror surface placed on the non-contact side of the contactor, and the contact-type comparative measurement is performed on the opposite end surfaces of the measurement object. Contact each contact, set the mirror surface parallel to the end surface of the measurement object,
Irradiating measurement light to both end surfaces of the measurement object to which the mirror surface is attached, and interference light between reflected light from the mirror surface of one end surface of the measurement object and reference light that is coherent with the reflected light, and The optical dimension between the mirror surfaces is measured based on the reflected light from the mirror surface of the other end surface of the object to be measured and the interference light of the reference light that is coherent with the reflected light, and from the optical dimension between the mirror surfaces. A phase correction value measuring method, comprising: measuring a mechanical dimension difference between the object to be measured and the reference object using a length measuring device that obtains a mechanical dimension of the object to be measured. 請求項１〜３に記載の位相補正値測定方法において、
前記基準物は光学的定数による位相変化を実質的に起こさない複素屈折率を持つ材質で形成され、該基準物の測定光が照射される面の表面粗さが測定に用いる光の波長より小さいことを特徴とする位相補正値測定方法。 In the phase correction value measuring method according to claims 1 to 3,
The reference object is formed of a material having a complex refractive index that does not substantially cause a phase change due to an optical constant, and the surface roughness of the surface irradiated with the measurement light of the reference object is smaller than the wavelength of light used for measurement. A method of measuring a phase correction value.
JP2004020349A 2004-01-28 2004-01-28 Phase correction value measurement method Expired - Fee Related JP4326356B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2004020349A JP4326356B2 (en) 2004-01-28 2004-01-28 Phase correction value measurement method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2004020349A JP4326356B2 (en) 2004-01-28 2004-01-28 Phase correction value measurement method

Publications (2)

Publication Number Publication Date
JP2005214740A JP2005214740A (en) 2005-08-11
JP4326356B2 true JP4326356B2 (en) 2009-09-02

Family

ID=34904293

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2004020349A Expired - Fee Related JP4326356B2 (en) 2004-01-28 2004-01-28 Phase correction value measurement method

Country Status (1)

Country Link
JP (1) JP4326356B2 (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4528028B2 (en) * 2004-05-25 2010-08-18 株式会社ミツトヨ Terminal
JP4878904B2 (en) * 2006-04-14 2012-02-15 株式会社ミツトヨ Dimensional difference measuring method and apparatus
JP2008309652A (en) * 2007-06-14 2008-12-25 National Institute Of Advanced Industrial & Technology Dimension measuring device and dimension measuring method
JP4947301B2 (en) * 2007-06-14 2012-06-06 独立行政法人産業技術総合研究所 Dimension measuring apparatus and dimension measuring method
JP6101035B2 (en) * 2012-10-11 2017-03-22 株式会社ミツトヨ Method for measuring phase correction value, and method for measuring dimension between end faces of end measure
JP7103086B2 (en) * 2018-09-05 2022-07-20 株式会社島津製作所 Material testing machine

Also Published As

Publication number Publication date
JP2005214740A (en) 2005-08-11

Similar Documents

Publication Publication Date Title
JP2561861B2 (en) Combined scale and interferometer
JP4326356B2 (en) Phase correction value measurement method
Weingärtner et al. System of four distance sensors for high-accuracy measurement of topography
JP2009014487A (en) Method and device for measuring refractive index
Lipus et al. Analysis of laser interferometer measurement uncertainty by simulating error sources
TWI383466B (en) An imprinting platform alignment and leveling measurement system
JP4203831B2 (en) Precision measurement method for group refractive index of optical materials
Lassila et al. Wave front and phase correction for double-ended gauge block interferometry
Sanjid et al. A review of diameter measurement and a proposal for the improvement thereof
JPS60186707A (en) Method of measuring surface profile
Leach NanoSurf IV: traceable measurement of surface texture at the National Physical Laboratory, UK
JP2001165629A (en) Shape measuring device and shape measuring method
JP2001227929A (en) Angle measuring method and apparatus
El Melegy et al. Recommendations for Acceptance Protocol for Flatness of Surface Plates
Weingaertner et al. Simultaneous distance, slope, curvature, and shape measurement with a multipurpose interferometer
Elmelegy Methods of Union Jack and XY-Grid in Surface Plate Measurements
JP6101035B2 (en) Method for measuring phase correction value, and method for measuring dimension between end faces of end measure
Höink et al. Application of diode lasers in interferometrical length measurements
JPH10260024A (en) Aspherical shape measuring device and method
JPH11173825A (en) Prism squareness-measuring method
Pekelsky et al. Bootstrap calibration of an autocollimator, index table and sine bar ensemble for angle metrology
Kozhevatov et al. A new in situ method for testing the optical thickness of removed transparent elements
JP5188140B2 (en) Dimension measurement method
Kim et al. Calibration of two-dimensional nanometer gratings using optical diffractometer and metrological atomic force microscope
Schulz et al. Fiber optical interferometric sensor based on a piezo-driven oscillation

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20061130

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20081121

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20081202

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20090129

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20090526

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20090609

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20120619

Year of fee payment: 3

R150 Certificate of patent or registration of utility model

Ref document number: 4326356

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20150619

Year of fee payment: 6

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

LAPS Cancellation because of no payment of annual fees