JP2002013920A - Interference fringe image processing device and image correcting method - Google Patents
Interference fringe image processing device and image correcting methodInfo
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- JP2002013920A JP2002013920A JP2000197485A JP2000197485A JP2002013920A JP 2002013920 A JP2002013920 A JP 2002013920A JP 2000197485 A JP2000197485 A JP 2000197485A JP 2000197485 A JP2000197485 A JP 2000197485A JP 2002013920 A JP2002013920 A JP 2002013920A
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は光波干渉を利用して
被検面起伏形状を計測する干渉計に関し、特に、参照面
から反射された参照光と被検面から反射された試料光と
の干渉によって生じる干渉縞画像の輝度データを撮像装
置で取得する干渉縞画像処理装置及び画像補正方法に関
する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interferometer for measuring an undulating shape of a test surface by using light wave interference, and more particularly to an interferometer for measuring a reference light reflected from a reference surface and a sample light reflected from the test surface. The present invention relates to an interference fringe image processing device and an image correction method for acquiring luminance data of an interference fringe image generated by interference with an imaging device.
【０００２】[0002]
【従来の技術】周知のように、被検面の起伏形状を被接
触で高精度に計測する方法のひとつとして、光波干渉を
ＣＣＤカメラなどの撮像装置で干渉縞画像の輝度データ
として取得する干渉計が知られている。この干渉計で
は、一般には、可干渉性の高いレーザを光源として使用
するが、干渉計を構成する光学素子により不要な反射光
が発生すると、不要な反射光が干渉して干渉ノイズとな
る。2. Description of the Related Art As is well known, as one of the methods for measuring the undulating shape of a surface to be measured with high accuracy by contact, an interference method of obtaining light wave interference as luminance data of an interference fringe image by an imaging device such as a CCD camera. The scale is known. In this interferometer, generally, a laser having high coherence is used as a light source. However, when unnecessary reflected light is generated by an optical element constituting the interferometer, the unnecessary reflected light interferes to generate interference noise.
【０００３】このような場合の干渉ノイズ対策として
は、光学部品に減反射膜を施したり、機能上差し支えな
いものは光学素子を楔構造にしたり、あるいは、干渉計
調整時に光学素子を光軸に対して姿勢を傾け配置するな
どの対策が可能である。しかし、これらの干渉ノイズの
ハードウェア的な対策では干渉計製作時の煩雑さを招く
ことになる。そして、ＣＣＤカメラの保護ガラスによる
干渉ノイズはハードウェア対策が困難であり、干渉縞画
像をＣＣＤカメラで撮像するときの大きな課題となって
いる。As a countermeasure against interference noise in such a case, an antireflection film is applied to an optical component, an optical element which does not interfere with the function has a wedge structure, or the optical element is set to an optical axis when adjusting the interferometer. It is possible to take countermeasures such as tilting the posture. However, hardware measures for these interference noises cause complications in the production of the interferometer. It is difficult to take measures against hardware for interference noise caused by the protection glass of the CCD camera, and this is a major problem when an interference fringe image is captured by the CCD camera.
【０００４】[0004]
【発明が解決しようとする課題】ところで、前述した干
渉ノイズは、光学素子の配置により固定的に生じるもの
で、一旦組立調整が完了すれば、固定的なノイズとして
扱うことが可能である。このため、本発明者らは、これ
らの固定的な干渉ノイズの性質を利用して、ソフトウェ
アにより干渉ノイズを補正することを特願平１１−１３
６８３２号出願・発明の名称「干渉縞画像の補正方法」
で提案した。つまり、その発明では、予めノイズ計測画
像を撮像して固有ノイズ分布データとして記憶してお
き、干渉縞撮像時に得られた干渉縞画像データと固有ノ
イズ分布データとを用いて、干渉縞画像データに含まれ
るノイズ分布をその都度求め、これらノイズ分布を干渉
縞画像データから差し引いて画像補正を行なうといった
処理を行なう。Incidentally, the above-described interference noise is fixedly generated by the arrangement of the optical elements, and can be treated as fixed noise once the assembly adjustment is completed. For this reason, the inventors of the present invention have proposed to correct the interference noise by using the property of the fixed interference noise by using software.
No. 6832 Application / Title of Invention "Correction method of interference fringe image"
Suggested. That is, in the present invention, a noise measurement image is captured in advance and stored as unique noise distribution data, and the interference fringe image data is obtained using A process is performed in which the noise distributions included are determined each time, and these noise distributions are subtracted from the interference fringe image data to perform image correction.
【０００５】しかしながら、この画像補正方法では、ノ
イズ分布をその都度算出する処理と干渉縞画像データか
らノイズ分布を差し引く処理が必要であるために、干渉
縞画像データ取得後のデータ処理に時間を要する問題が
ある。However, in this image correction method, a process for calculating the noise distribution each time and a process for subtracting the noise distribution from the interference fringe image data are required, so that it takes time for data processing after obtaining the interference fringe image data. There's a problem.
【０００６】本発明の目的は、以上に述べたような従来
における干渉計の干渉縞画像の補正方法の問題に鑑み、
より簡素な処理にて干渉ノイズ低減を実現することでデ
ータ処理の高速化を図れる干渉縞画像処理装置及び画像
補正方法を得るにある。SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problem of a conventional method for correcting an interference fringe image of an interferometer.
An object of the present invention is to provide an interference fringe image processing apparatus and an image correction method that can speed up data processing by realizing interference noise reduction with simpler processing.
【０００７】[0007]
【課題を解決するための手段】この目的を達成するた
め、本発明は、光源からの可干渉光を参照面と被検面に
照射し、前記参照面によって反射された参照光と、前記
被検面から反射された試料光との干渉によって生じる干
渉縞を、撮像装置により干渉縞画像の輝度データとして
取得して被検面起伏形状を計測する干渉計において、前
記撮像装置より予め撮像された参照光画像の各点の輝度
データを記憶するメモリと、このメモリから読み出され
た参照光画像の輝度データから前記干渉縞画像の各点の
輝度データを観測領域内の対応する前記各点にて除算し
て輝度変換補正を施こす処理装置とを備え、この輝度変
換補正後の干渉縞画像の輝度データを用いて、被検面起
伏形状を算出する干渉縞画像処理装置を提案するもので
ある。In order to achieve this object, the present invention irradiates a reference surface and a test surface with coherent light from a light source, and reflects the reference light reflected by the reference surface and the target light. An interference fringe generated by interference with the sample light reflected from the test surface is acquired in advance by the imaging device in an interferometer that measures the undulation shape of the test surface by acquiring the luminance data of the interference fringe image by the imaging device. A memory for storing the luminance data of each point of the reference light image, and the luminance data of each point of the interference fringe image from the luminance data of the reference light image read from this memory to the corresponding point in the observation area. And a processing device for performing luminance conversion correction by dividing the interference fringe image by using the luminance data of the interference fringe image after the luminance conversion correction. is there.
【０００８】また、本発明においては、この目的は、光
源からの可干渉光を参照面と被検面に照射し、前記参照
面によって反射された参照光と、前記被検面から反射さ
れた試料光との干渉によって生じる干渉縞を、撮像装置
により干渉縞画像の輝度データとして取得して被検面起
伏形状を計測する干渉計において、前記干渉縞画像の各
点の輝度データを、前記撮像装置で予め撮像された参照
光画像の前記各点に対応する量の輝度データにより観測
領域内の対応する前記各点にて除算して輝度変換補正を
施し、この輝度変換補正後の干渉縞画像の輝度データを
用いて、被検面起伏形状を算出する干渉縞画像の補正方
法によっても達成される。Further, in the present invention, the object is to irradiate the coherent light from the light source to the reference surface and the test surface, and to reflect the reference light reflected by the reference surface and the reference light reflected from the test surface. In an interferometer that acquires interference fringes caused by interference with the sample light as luminance data of the interference fringe image by an imaging device and measures the undulation shape of the surface to be inspected, the luminance data of each point of the interference fringe image is captured by the imaging device. An interference fringe image after the luminance conversion correction is obtained by dividing by the respective points in the observation area by the luminance data of the amount corresponding to the respective points of the reference light image captured in advance by the apparatus and dividing by the respective points. This is also achieved by an interference fringe image correction method for calculating the undulating shape of the test surface using the luminance data of
【０００９】[0009]
【発明の実施の形態】以下、図面について本発明の実施
例の詳細を説明する。図１は本発明が対象とする代表的
な干渉計の一つであるフィゾー型干渉計を示している。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a Fizeau interferometer which is one of the representative interferometers to which the present invention is applied.
【００１０】図１において、レーザ光源１からのレーザ
光束はレンズ２よりビーム径を拡大され、ビームスプリ
ッタ３を透過してコリメートレンズ４にて平行光束とさ
れ、この平行光束は参照面５で反射された参照光と参照
面５を透過して被検面６で反射された試料光を生成す
る。両光の光波干渉により得られる干渉縞をビームスプ
リッタで反射させて、ＣＣＤカメラなどの撮像装置７で
撮像する。この撮像装置７の出力は干渉縞画像の輝度デ
ータを処理するＣＰＵなどの処理装置８に入力され、同
処理装置８で処理された干渉縞画像がＣＲＴなどで構成
する図２の表示装置９に表示される。本発明において
は、この処理装置８は詳細を後述する参照光画像の各点
の輝度データを格納できるメモリ１０を内蔵し、時間的
に変化しない同参照光の輝度データを用いた演算処理が
行われるが、この演算処理については後述から明らかに
なる。In FIG. 1, a laser beam from a laser light source 1 is enlarged in beam diameter by a lens 2, passes through a beam splitter 3, is converted into a parallel beam by a collimator lens 4, and the parallel beam is reflected by a reference surface 5. The generated reference light and sample light transmitted through the reference surface 5 and reflected by the test surface 6 are generated. The interference fringes obtained by the light wave interference of the two lights are reflected by a beam splitter and imaged by an imaging device 7 such as a CCD camera. The output of the imaging device 7 is input to a processing device 8 such as a CPU that processes the luminance data of the interference fringe image, and the interference fringe image processed by the processing device 8 is sent to a display device 9 of FIG. Is displayed. In the present invention, the processing device 8 has a built-in memory 10 capable of storing luminance data of each point of a reference light image, which will be described in detail later, and performs arithmetic processing using luminance data of the reference light which does not change with time. However, this calculation process will be clarified later.
【００１１】図３は前述したフィゾー型干渉計の参照面
５、被検面６、参照光と試料光が光路上で介在する光学
素子、観測位置の配置関係の模式図であり、ここでは、
参照光をＡ、試料光をＢとし、参照光Ａが光学素子Ｔを
透過する成分をＡ1 、光学素子Ｔの内部で反射されて一
往復し、観測位置側Ｕに向かう成分をＡ2 としてある。
また、同様に試料光Ｂについても光学素子Ｔを透過する
成分と光学素子Ｔの内部で一往復する成分をそれぞれＢ
1 、Ｂ2 としてある。Ａ1 、Ａ2 、Ｂ1 、Ｂ2は図示の
都合上異なる位置に記載されているが、これら４つの光
の干渉を考慮する際には、全て同一光軸上に存在するも
のとして理解される。FIG. 3 is a schematic view showing the arrangement of the reference plane 5, the test plane 6, the optical element in which the reference light and the sample light are interposed on the optical path, and the observation position of the Fizeau interferometer.
The reference light is A, the sample light is B, the component of the reference light A passing through the optical element T is A 1 , and the component that is reflected inside the optical element T and makes one round trip and heads toward the observation position U is A 2. is there.
Similarly, for the sample light B, the component that transmits through the optical element T and the component that makes one round trip inside the optical element T are represented by B and B, respectively.
1 and B 2 . Although A 1 , A 2 , B 1 , and B 2 are shown at different positions for convenience of illustration, they are understood as all existing on the same optical axis when considering the interference of these four lights. You.
【００１２】ちなみに、図３における各符号の意味・内
容を整理しておくと、次の通りである。 Ａ1 ：参照面Ｒからの反射光Ａのうち、光学素子Ｔを透
過する成分 Ａ2 ：参照面Ｒからの反射光Ａのうち、光学素子Ｔ内で
の反射により余分に一往復して透過する成分 Ｂ1 ：被検面Ｓからの反射光Ｂのうち、光学素子Ｔを透
過する成分 Ｂ2 ：被検面Ｓからの反射光Ｂのうち、光学素子Ｔ内で
の反射により余分に一往復して透過する成分 ｌ：参照面Ｒと被検面Ｓ間の距離 Ｌ：参照面Ｒと観測位置Ｕ間の距離 ｔ：各撮像位置において計画外の干渉ノイズを発生させ
る光学素子Ｔの厚みIncidentally, the meaning and contents of each code in FIG. 3 are summarized as follows. A 1 : A component of the reflected light A from the reference surface R that passes through the optical element T A 2 : A component of the reflected light A from the reference surface R that travels one extra round trip due to reflection in the optical element T Component B 1 : of the reflected light B from the test surface S, the component transmitted through the optical element T B 2 : of the reflected light B from the test surface S, one extra due to reflection in the optical element T Reciprocally transmitted component l: distance between reference surface R and test surface S L: distance between reference surface R and observation position U t: thickness of optical element T that generates unplanned interference noise at each imaging position
【００１３】次に、撮像装置７で観測される２次元の干
渉縞のある一点の干渉現象について説明すると、Ａ1 、
Ａ2 、Ｂ1 、Ｂ2 の振幅をそれぞれａ1 、ａ2 、ｂ1 、
ｂ2とおき、参照面位置を原点として図３に示した配置
関係により４つの光を数式により記述すれば、[0013] Subsequently explained interference phenomenon one point with a two-dimensional interference fringes are observed by the imaging device 7, A 1,
The amplitudes of A 2 , B 1 , and B 2 are represented by a 1 , a 2 , b 1 ,
b 2 Distant, the arrangement relationship shown a reference surface position in Fig. 3 as the origin of the four light if described by formula,
【数１】 で表わすことができ、これらの式のうち（１−２）式、
（１−４）式には光学素子Ｔの影響であるｔが含まれて
いる。(Equation 1) Which can be expressed by the following equation (1-2):
The expression (1-4) includes t which is an influence of the optical element T.
【００１４】そして（１−１）式〜（１−４）式で示し
たこれら４つの光による干渉強度は、The interference intensities of these four lights shown in the equations (1-1) to (1-4) are as follows:
【数２】 となる。ここで、光学素子Ｔの内部反射により発生する
Ａ2 の振幅を減衰係数εを用いて、 ａ2 ＝εａ1 （３） で表すと、同一の光学素子Ｔを経て観測位置に達するＢ
1 とＢ2 の関係についても同様に ｂ2 ＝εｂ1 （４） で表すことができる。(Equation 2) Becomes Here, when the amplitude of A 2 generated by the internal reflection of the optical element T is represented by a 2 = εa 1 (3) using the attenuation coefficient ε, B reaching the observation position via the same optical element T
The relationship between 1 and B 2 can be similarly expressed by b 2 = εb 1 (4).
【００１５】ここに、（３）式、（４）式を（２）式に
代入すると、次式が得られる。Here, by substituting equations (3) and (4) into equation (2), the following equation is obtained.
【数３】 (Equation 3)
【００１６】次に、Ｉ’の実数部をとるとNext, taking the real part of I '
【数４】 となり、４つの光による干渉強度を表す式が得られる。(Equation 4) Thus, an expression representing the interference intensity of the four lights is obtained.
【００１７】つまり、（６）式中、右辺第一項、第二項
は光学素子Ｔの内部反射によって発生する干渉ノイズを
表しており、光学素子Ｔの厚みに依存した干渉ノイズ強
度の振幅はそれぞれ２εａ1 2、２εｂ1 2であることを表
している。また、右辺第三項目は、光学素子Ｔによって
発生する干渉ノイズが被検面起伏形状によって発生する
干渉強度により強度の振幅変調がなされたものと解釈で
きる。（６）式をまとめると、That is, in the equation (6), the first and second terms on the right side represent interference noise generated by internal reflection of the optical element T, and the amplitude of the interference noise intensity depending on the thickness of the optical element T is each 2εa 1 2, it indicates that a 2εb 1 2. The third item on the right-hand side can be interpreted as that the intensity of the interference noise generated by the optical element T is modulated by the interference intensity generated by the undulating shape of the test surface. (6) Summarizing the equation,
【数５】 という形で表せる。(Equation 5) Can be expressed in the form
【００１８】一方、参照光Ａのみの場合に、Ａ1 、Ａ2
によって発生する干渉は次式で表される。On the other hand, when only the reference light A is used, A 1 , A 2
The interference caused by the above is expressed by the following equation.
【数６】 (Equation 6)
【００１９】ここで、（６）′式を（７）式で除算する
と、Here, dividing equation (6) 'by equation (7) gives:
【数７】 となり、光学素子Ｔに依存した項；ｃｏｓ（ｋ２ｔ）を
削除することができる。(Equation 7) And the term dependent on the optical element T; cos (k2t) can be deleted.
【００２０】ここに、前述したことは２次元の干渉縞画
像上の各撮像点にて成立する。このことは、（６）式で
示した参照光と試料光による干渉強度と（７）式で示し
た参照光による干渉強度が、撮像装置８によりある階調
の輝度データとして得られたとき、前者から後者を各撮
像点ごとに除算して輝度変換を施すことで、干渉計を構
成する光学部品によって発生する干渉ノイズを低減する
ことができることを意味する。なお、参照光強度は時間
的に変動しないものであるために、予め撮像して処理装
置８のメモリ１０に輝度データを保持しておけば良い。
干渉縞画像取得後にノイズ低減処理に要する処理は除算
の１回のみで済む。Here, the above holds for each imaging point on the two-dimensional interference fringe image. This means that when the interference intensity due to the reference light and the sample light represented by the expression (6) and the interference intensity due to the reference light represented by the expression (7) are obtained as luminance data of a certain gradation by the imaging device 8, By dividing the former to the latter for each imaging point and performing luminance conversion, it means that interference noise generated by optical components constituting the interferometer can be reduced. Since the reference light intensity does not fluctuate with time, it is sufficient that the image is captured in advance and the luminance data is stored in the memory 10 of the processing device 8.
The processing required for the noise reduction processing after the acquisition of the interference fringe image is performed only once in the division.
【００２１】他方、光源の波長可変かあるいは、参照面
の平行移動により得られた３枚の位相シフト干渉縞の場
合、On the other hand, in the case of three phase-shift interference fringes obtained by changing the wavelength of the light source or by translating the reference surface,
【数８】 に対して、参照光画像の除算によりノイズ低減を施した
干渉縞は、(Equation 8) On the other hand, the interference fringes that have been subjected to noise reduction by dividing the reference light image
【数９】 となる。(Equation 9) Becomes
【００２２】これらの（１０−１）式〜（１０−３）式
からFrom the equations (10-1) to (10-3),
【数１０】 となる関係が得られる。よって、被検面起伏形状に相当
する干渉縞位相φは、(Equation 10) The following relationship is obtained. Therefore, the interference fringe phase φ corresponding to the undulating shape of the test surface is
【数１１】 で求められる。つまり、本発明による画像補正方法によ
りノイズ低減処理を施した干渉縞においても位相シフト
法を適用することが可能である。[Equation 11] Is required. That is, the phase shift method can be applied to the interference fringes subjected to the noise reduction processing by the image correction method according to the present invention.
【００２３】撮像各点に対して、以上に述べたような処
理を施せば、２次元の干渉縞画像上に観測される干渉ノ
イズを低減させることができ、この結果、被検面起伏形
状を高精度に計測することが可能となる。By performing the above-described processing on each point of imaging, it is possible to reduce interference noise observed on a two-dimensional interference fringe image. It is possible to measure with high accuracy.
【００２４】[0024]
【発明の効果】以上の説明から明らかなように、本発明
の干渉縞画像処理装置及び画像補正方法では、撮像装置
より得られた干渉縞画像の輝度データを参照光画像の輝
度データを１回除算するだけで、干渉縞に含まれる固定
の干渉ノイズを低減することができるために、処理時間
の大幅な短縮が見込める。As is apparent from the above description, in the interference fringe image processing apparatus and the image correction method of the present invention, the luminance data of the interference fringe image obtained from the image pickup apparatus is converted into the luminance data of the reference light image once. Since the fixed interference noise included in the interference fringes can be reduced only by the division, the processing time can be greatly reduced.
【図１】本発明を適用できるフィゾー型干渉計の概念図
である。FIG. 1 is a conceptual diagram of a Fizeau interferometer to which the present invention can be applied.
【図２】本発明で用いる処理装置のブロックダイヤグラ
ムである。FIG. 2 is a block diagram of a processing apparatus used in the present invention.
【図３】同フィゾー型干渉計の参照面、被検面、光学素
子、観測位置の配置関係の模式図である。FIG. 3 is a schematic diagram of an arrangement relationship among a reference surface, a test surface, an optical element, and an observation position of the Fizeau interferometer.
１ レーザ光源 ２ レンズ ３ ビームスプリッタ ４ コリメートレンズ ５ 参照面 ６ 被検面 ７ 撮像装置 ８ 処理装置 ９ 表示装置 １０ メモリ REFERENCE SIGNS LIST 1 laser light source 2 lens 3 beam splitter 4 collimating lens 5 reference surface 6 test surface 7 imaging device 8 processing device 9 display device 10 memory
───────────────────────────────────────────────────── フロントページの続き Ｆターム(参考） 2F065 AA54 DD03 DD04 FF42 FF51 GG04 HH13 JJ03 JJ26 LL04 LL46 QQ21 QQ24 QQ28 QQ32 QQ34 SS13 5B057 AA01 BA02 CA02 CA08 CA12 CA16 CB02 CB08 CB12 CB16 CC01 CE02 CH11 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F065 AA54 DD03 DD04 FF42 FF51 GG04 HH13 JJ03 JJ26 LL04 LL46 QQ21 QQ24 QQ28 QQ32 QQ34 SS13 5B057 AA01 BA02 CA02 CA08 CA12 CA16 CB02 CB08 CB12 CH11 CC01 CE
Claims (2)
照射し、前記参照面によって反射された参照光と、前記
被検面から反射された試料光との干渉によって生じる干
渉縞を、撮像装置により干渉縞画像の輝度データとして
取得して被検面起伏形状を計測する干渉計において、 前記撮像装置より予め撮像された参照光画像の各点の輝
度データを記憶するメモリと、前記干渉縞画像の各点の
輝度データを前記メモリから読み出された参照光画像の
輝度データで観測領域内の対応する前記各点にて除算し
て輝度変換補正を施こす処理装置とを備え、この輝度変
換補正後の干渉縞画像の輝度データを用いて、被検面起
伏形状を算出することを特徴とする干渉縞画像処理装
置。1. A reference surface and a test surface are irradiated with coherent light from a light source, and interference fringes generated by interference between the reference light reflected by the reference surface and the sample light reflected from the test surface. In an interferometer that acquires the luminance data of the interference fringe image by the imaging device and measures the undulating shape of the test surface, a memory that stores the luminance data of each point of the reference light image that is captured in advance by the imaging device, A processing device for performing luminance conversion correction by dividing luminance data of each point of the interference fringe image by luminance data of the reference light image read from the memory by the corresponding points in the observation area. An interference fringe image processing apparatus that calculates the undulating shape of the test surface using the luminance data of the interference fringe image after the luminance conversion correction.
照射し、前記参照面によって反射された参照光と、前記
被検面から反射された試料光との干渉によって生じる干
渉縞を、撮像装置により干渉縞画像の輝度データとして
取得して被検面起伏形状を計測する干渉計において、 前記干渉縞画像の各点の輝度データを、前記撮像装置で
予め撮像された参照光画像の前記各点に対応する量の輝
度データにより観測領域内の対応する前記各点にて除算
して輝度変換補正を施し、この輝度変換補正後の干渉縞
画像の輝度データを用いて、被検面起伏形状を算出する
ことを特徴とする干渉縞画像の補正方法。2. A coherent light from a light source is applied to a reference surface and a test surface, and interference fringes generated by interference between the reference light reflected by the reference surface and the sample light reflected from the test surface. In an interferometer that acquires the luminance data of the interference fringe image by the imaging device and measures the undulation shape of the surface to be inspected, the luminance data of each point of the interference fringe image is referred to as a reference light image previously captured by the imaging device. The luminance conversion of the interference fringe image is performed using the luminance data of the interference fringe image after the luminance conversion of the corresponding point in the observation area is divided by the luminance data of the amount corresponding to each of the points. A method for correcting an interference fringe image, comprising calculating a surface undulation shape.
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|---|---|---|---|
| JP2000197485A JP2002013920A (en) | 2000-06-30 | 2000-06-30 | Interference fringe image processing device and image correcting method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000197485A JP2002013920A (en) | 2000-06-30 | 2000-06-30 | Interference fringe image processing device and image correcting method |
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ID=18695809
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010281741A (en) * | 2009-06-05 | 2010-12-16 | Nikon Corp | Noise eliminator, noise eliminating method, noise position detector, noise position detecting method, measuring system, and program |
| CN112179505A (en) * | 2020-09-23 | 2021-01-05 | 中国科学院光电技术研究所 | Image processing device and method based on wedge-shaped flat plate shearing interferometer |
-
2000
- 2000-06-30 JP JP2000197485A patent/JP2002013920A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010281741A (en) * | 2009-06-05 | 2010-12-16 | Nikon Corp | Noise eliminator, noise eliminating method, noise position detector, noise position detecting method, measuring system, and program |
| CN112179505A (en) * | 2020-09-23 | 2021-01-05 | 中国科学院光电技术研究所 | Image processing device and method based on wedge-shaped flat plate shearing interferometer |
| CN112179505B (en) * | 2020-09-23 | 2022-08-02 | 中国科学院光电技术研究所 | Image processing device and method based on wedge-shaped flat plate shearing interferometer |
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