JP2000082433A - Electron microscope - Google Patents
Electron microscopeInfo
- Publication number
- JP2000082433A JP2000082433A JP10248175A JP24817598A JP2000082433A JP 2000082433 A JP2000082433 A JP 2000082433A JP 10248175 A JP10248175 A JP 10248175A JP 24817598 A JP24817598 A JP 24817598A JP 2000082433 A JP2000082433 A JP 2000082433A
- Authority
- JP
- Japan
- Prior art keywords
- image
- frame memory
- rotation
- photographing
- center
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000010586 diagram Methods 0.000 description 6
- 230000005284 excitation Effects 0.000 description 3
- 230000001133 acceleration Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000000007 visual effect Effects 0.000 description 2
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000003384 imaging method Methods 0.000 description 1
Landscapes
- Electron Sources, Ion Sources (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は電流軸合わせを自動
化するようにした電子顕微鏡に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron microscope in which current axis alignment is automated.
【０００２】[0002]
【従来の技術】電子顕微鏡で像観察を行う場合、電流軸
がずれていると対物レンズの励磁電流を可変してフォー
カス調整した時観察像は移動する。即ち、図６に示すよ
うに、回転中心（電流軸）が視野中心からずれている場
合、対物レンズの励磁電流を可変してフォーカス（以
下、フォーカスと称する）を変更するとこの回転中心の
周りを観察像が回転してしまう（図では矢印で時計方向
に回転していることを示している）。そのため、この回
転中心を視野中心に一致させるようにコンデンサレンズ
（ＣＬ）のアライメントを調整する必要があり、従来、
蛍光板上の像を観察しながら、調整するようにしてい
た。2. Description of the Related Art When performing image observation with an electron microscope, if the current axis is shifted, the observed image moves when the focus is adjusted by varying the exciting current of the objective lens. That is, as shown in FIG. 6, when the center of rotation (current axis) is shifted from the center of the field of view, when the excitation current of the objective lens is varied to change the focus (hereinafter, referred to as focus), the area around the center of rotation is changed. The observed image is rotated (in the figure, the arrow indicates clockwise rotation). Therefore, it is necessary to adjust the alignment of the condenser lens (CL) so that the center of rotation coincides with the center of the visual field.
The adjustment was made while observing the image on the phosphor plate.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、フォー
カスを変更しつつ蛍光板に投影された像を目視しなが
ら、調整する作業は容易なことではなく、また個人によ
って調整精度にバラツキが生じるという問題があった。
本発明は上記課題を解決するためのもので、従来手作業
で行っていた電流軸合わせの調整作業を自動化し、調整
精度に個人差が生じないようにすることを目的とする。However, it is not easy to make adjustments while visually observing the image projected on the fluorescent screen while changing the focus, and there is a problem that the adjustment accuracy varies among individuals. Was.
SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to automate a manual adjustment operation of a current axis, which is conventionally performed manually, so that there is no individual difference in adjustment accuracy.
【０００４】[0004]
【課題を解決するための手段】本発明は、蛍光板上の像
を撮影する撮影手段と、撮影手段で撮影された像をデジ
タル画像として取り込み、画像の積算を行うフレームメ
モリと、フレームメモリで積算した画像を表示する表示
手段と、対物レンズの励磁電流を可変してフォーカス調
整したときの前記画像の軌跡から画像の回転中心を算出
するとともに、電流軸合わせ補正量を算出する演算処理
制御手段と、演算処理制御手段により制御され、前記算
出された補正量に応じて電流軸合わせ補正を行う手段と
を備えたことを特徴とする。SUMMARY OF THE INVENTION The present invention relates to a photographing means for photographing an image on a fluorescent screen, a frame memory for taking in an image photographed by the photographing means as a digital image and integrating the images, and a frame memory for integrating the images. Display means for displaying the obtained image, and arithmetic processing control means for calculating the rotation center of the image from the locus of the image when the focus current is adjusted by varying the excitation current of the objective lens, and calculating the current axis alignment correction amount. And means for performing current axis alignment correction in accordance with the calculated correction amount, which is controlled by arithmetic processing control means.
【０００５】[0005]
【発明の実施の形態】以下、本発明の実施の形態につい
て説明する。図１は本発明の電子顕微鏡の基本構成を示
すものである。電子銃１１から放出された電子ビームは
照射レンズと偏向コイルとからなるレンズ系７を通して
試料１０に照射され、試料透過像は対物レンズと結像レ
ンズからなるレンズ系７′により蛍光板１上に結像され
る。蛍光板１上の像はテレビカメラ２で撮影され、フレ
ームメモリ３にデジタル画像として取り込まれ、画像は
ディスプレイ９に表示される。ＣＰＵ４はフレームメモ
リに取り込んだ画像データから所定の演算処理、例えば
後述するように画像回転方向の動きベクトル等の抽出、
回転中心の算出等の処理を行う。また、ＣＰＵ４はイン
ターフェース５，６を介してレンズ系７，７′の制御、
ゴニオステージ８の制御を行っている。なお、画像の演
算はＣＰＵ４上のプログラムにより行うことに限らず、
例えばフレームメモリ３上に専用のチップを実装して行
っても良く、演算結果はＣＰＵ４によって判断する。そ
の結果、補正が必要であれば、インターフェース５，６
を介してレンズ系７の偏向コイルにフィードバックされ
て電流軸合わせが行われ、また、ディスプレイ９に表示
される。Embodiments of the present invention will be described below. FIG. 1 shows the basic configuration of an electron microscope according to the present invention. The electron beam emitted from the electron gun 11 is irradiated on the sample 10 through a lens system 7 including an irradiation lens and a deflection coil, and a sample transmission image is formed on the fluorescent screen 1 by a lens system 7 'including an objective lens and an imaging lens. Imaged. The image on the fluorescent screen 1 is photographed by the television camera 2, taken into the frame memory 3 as a digital image, and displayed on the display 9. The CPU 4 performs predetermined arithmetic processing from the image data fetched into the frame memory, for example, extraction of a motion vector in the image rotation direction as described later,
Processing such as calculation of the rotation center is performed. Further, the CPU 4 controls the lens systems 7, 7 'through the interfaces 5, 6,
The gonio stage 8 is controlled. The calculation of the image is not limited to being performed by the program on the CPU 4,
For example, a dedicated chip may be mounted on the frame memory 3, and the calculation result is determined by the CPU 4. As a result, if correction is necessary, the interfaces 5, 6
Is fed back to the deflection coil of the lens system 7 to perform current axis alignment, and is displayed on the display 9.
【０００６】次に、電流軸合わせを自動化する方法を図
２〜５により説明する。図２はフレームメモリ３に取り
込まれたフォーカス変更前の画像をディスプレイ９上に
表示したものであり、観測点Ａ，Ｂ，Ｃ，Ｄの像（●で
表示）と視野中心（×で表示）が示されている。いま、
フォーカスを変更しつつフレームメモリに画像を取り込
んで画像の積算を行うと、あたかも露光時間を長くして
北極星を撮影した時の写真のように、回転中心の回りに
軌跡を描いたような、図３に示すような像が得られる。
図３において、観測点Ａ，Ｂ，Ｃ，Ｄにそれぞれの黒丸
が複数個繋がって表示されているのは、その軌跡を示し
ており、また、回転方向は矢印で示している。このよう
にフレームメモリに取り込んだ画像に対してＣＰＵ４に
おいて処理を行い、各観測点Ａ，Ｂ，Ｃ，Ｄについて回
転方向の動きベクトルを抽出する。動きベクトル（始点
と終点が同一円周上にある）は、図４の矢印で示した通
りのもので、その大きさと向きは回転中心からの距離と
像の回転角に依存する。Next, a method for automating current axis alignment will be described with reference to FIGS. FIG. 2 shows the image before the focus change captured in the frame memory 3 on the display 9. The images of the observation points A, B, C and D (indicated by ●) and the center of the visual field (indicated by x) It is shown. Now
When the image is integrated into the frame memory while changing the focus, and the image is integrated, the trajectory is drawn around the center of rotation, as in a photo taken with a longer exposure time and a polar star. An image as shown in FIG.
In FIG. 3, a plurality of black circles connected to the observation points A, B, C, and D are displayed to indicate their trajectories, and the rotation directions are indicated by arrows. The CPU 4 performs processing on the image captured in the frame memory in this way, and extracts a motion vector in the rotation direction for each of the observation points A, B, C, and D. The motion vector (the starting point and the ending point are on the same circle) is as shown by the arrow in FIG. 4, and the size and direction depend on the distance from the rotation center and the rotation angle of the image.
【０００７】図５のＸ，Ｙ座標系において、Ｏ′（ｘ
0 ，ｙ0 ）を回転中心、ｒを回転中心から観測点までの
距離、Ｐ1 （ｘ1 ，ｙ1 ），Ｐ2 （ｘ2 ，ｙ2 ）を１つ
の観測点のフォーカス調整前後の位置、換言すれば、動
きベクトルの始点、終点、ｄを動きベトクルの大きさと
すると、 ｄ＝〔（ｘ2 − ｘ1 ）2 ＋（ｙ2 − ｙ1 ）2 〕1/2 ……（１） ｒ＝ｄ／（２ sin（θ／２）） ……（２） 〔（ｘ1 −ｘ0 ）2 ＋（ｙ1 − ｙ0 ）2 〕1/2 ＝ｒ ……（３） 〔（ｘ2 −ｘ0 ）2 ＋（ｙ2 − ｙ0 ）2 〕1/2 ＝ｒ ……（４） が成立する。ここで、Ｐ1 （ｘ1 ，ｙ1 ），Ｐ2 （ｘ
2 ，ｙ2 ）は観測される位置あり、これら各座標値を用
いて（１）式よりｄが求められる。In the X, Y coordinate system of FIG. 5, O '(x
0 , y 0 ) is the rotation center, r is the distance from the rotation center to the observation point, and P 1 (x 1 , y 1 ) and P 2 (x 2 , y 2 ) are the positions before and after the focus adjustment of one observation point. In other words, assuming that the starting point and the ending point of the motion vector and d are the size of the motion vector, d = [(x 2 −x 1 ) 2 + (y 2 −y 1 ) 2 ] 1/2 (1) r = d / (2 sin (θ / 2)) (2) [(x 1 −x 0 ) 2 + (y 1 −y 0 ) 2 ] 1/2 = r (3) [(x 2− x 0 ) 2 + (y 2 −y 0 ) 2 ] 1/2 = r (4) Here, P 1 (x 1 , y 1 ), P 2 (x
2 , y 2 ) is the position to be observed, and d is obtained from equation (1) using these coordinate values.
【０００８】ところで、像の回転角θは、例えば磁界レ
ンズを用いた場合には、 θ＝０．１８６３ＮＩ／Φ1/2 ……（５） θ：回転角 Φ：軸上電位（加速電圧） ＮＩ：アンペアターン で与えられる。アンペアターンＮＩは対物レンズの規格
によって特定でき、また、加速電圧についても装置から
取得可能な値であるのでＮＩ、Φは既知の値である。従
って、励磁によってフォーカス調整をしたときのＮＩに
応じて（５）式より回転角θが分かり、従って、（２）
式よりｒが、（３）、（４）式よりＯ′（ｘ0 ，ｙ0 ）
が求められ、回転中心を算出することができる。The rotation angle θ of the image is, for example, when a magnetic lens is used, θ = 0.1863 NI / Φ 1/2 (5) θ: rotation angle Φ: on-axis potential (acceleration voltage) NI: given in ampere turns. Since the ampere-turn NI can be specified by the standard of the objective lens, and the acceleration voltage is a value that can be obtained from the apparatus, NI and Φ are known values. Therefore, the rotation angle θ can be found from the equation (5) according to the NI when the focus is adjusted by the excitation, and accordingly, (2)
From the equations, r is O '(x 0 , y 0 ) from the equations (3) and (4).
Is obtained, and the rotation center can be calculated.
【０００９】このように１つの観測点の軌跡から回転中
心が求められるが、幾つかの観測点の軌跡からそれぞれ
回転中心を求め、それらの平均をとって回転中心を算出
するようにしてもよい。こうして求めた回転中心を視野
中心に一致させるには、ＣＰＵ４によって補正量を計算
し、算出した補正量に基づいて偏向コイルの電流制御を
行って電流軸合わせを行う。こうして従来手作業で行っ
ていた電流軸合わせ調整作業を自動化することが可能と
なる。As described above, the center of rotation is obtained from the trajectory of one observation point. Alternatively, the center of rotation may be obtained from the trajectories of several observation points, and the rotation center may be calculated by taking the average of them. . In order to make the rotation center thus found coincide with the center of the field of view, a correction amount is calculated by the CPU 4, and the current axis of the deflection coil is controlled based on the calculated correction amount. In this way, it is possible to automate the current axis alignment adjustment work conventionally performed manually.
【００１０】なお、上記説明では、完全自動化の例につ
いて説明したが、回転の軌跡をディスプレイの画像上で
人間が指定し、これを入力することによりＣＰＵ４で回
転中心を算出するようにしても良い。In the above description, an example of complete automation has been described. However, a human may specify the trajectory of rotation on an image on the display, and the CPU 4 may calculate the center of rotation by inputting this. .
【００１１】[0011]
【発明の効果】以上のように本発明によれば、電流軸合
わせの調整作業を自動化することができ、調整作業が簡
素化され、また特定の技術、教育や経験を要しなくても
調整作業を行うことができるので、個人差による調整精
度の違いをなくすことが可能となる。As described above, according to the present invention, the adjustment work of the current axis alignment can be automated, the adjustment work can be simplified, and the adjustment can be performed without requiring any specific technology, education or experience. Since the work can be performed, it is possible to eliminate a difference in adjustment accuracy due to individual differences.
【図１】 本発明の電子顕微鏡の基本構成を示す図であ
る。FIG. 1 is a diagram showing a basic configuration of an electron microscope of the present invention.
【図２】 フォーカス変更前の像を示す図である。FIG. 2 is a diagram showing an image before a focus change.
【図３】 フォーカス変更後の像を示す図である。FIG. 3 is a diagram showing an image after a focus change.
【図４】 各観測点の動きベクトルを説明する図であ
る。FIG. 4 is a diagram illustrating a motion vector of each observation point.
【図５】 回転中心の算出を説明する図である。FIG. 5 is a diagram illustrating calculation of a rotation center.
【図６】 従来のフォーカス調整方法を説明する図であ
る。FIG. 6 is a diagram illustrating a conventional focus adjustment method.
１…蛍光板、２…ＴＶカメラ、３…フレームメモリ、４
…ＣＰＵ、５，６…インターフェース、７，７′…レン
ズ系、８…ゴニオステージ、９…ディスプレイ、１０…
試料、１１…電子銃。DESCRIPTION OF SYMBOLS 1 ... Fluorescent screen, 2 ... TV camera, 3 ... Frame memory, 4
... CPU, 5, 6 ... interface, 7, 7 '... lens system, 8 ... goniometer, 9 ... display, 10 ...
Sample, 11 ... Electron gun.
Claims (1)
影手段で撮影された像をデジタル画像として取り込み、
画像の積算を行うフレームメモリと、フレームメモリで
積算した画像を表示する表示手段と、対物レンズの励磁
電流を可変してフォーカス調整したときの前記画像の軌
跡から画像の回転中心を算出するとともに、電流軸合わ
せ補正量を算出する演算処理制御手段と、演算処理制御
手段により制御され、前記算出された補正量に応じて電
流軸合わせ補正を行う手段とを備えた電子顕微鏡。A photographing means for photographing an image on a fluorescent screen; and an image photographed by the photographing means is taken in as a digital image.
A frame memory for accumulating images, a display means for displaying the images accumulated in the frame memory, and calculating the center of rotation of the image from the locus of the image when the focus is adjusted by varying the exciting current of the objective lens; An electron microscope comprising: an arithmetic processing control unit that calculates a current axis alignment correction amount; and a unit that is controlled by the arithmetic processing control unit and that performs a current axis alignment correction in accordance with the calculated correction amount.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24817598A JP3522121B2 (en) | 1998-09-02 | 1998-09-02 | electronic microscope |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24817598A JP3522121B2 (en) | 1998-09-02 | 1998-09-02 | electronic microscope |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2000082433A true JP2000082433A (en) | 2000-03-21 |
| JP3522121B2 JP3522121B2 (en) | 2004-04-26 |
Family
ID=17174333
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP24817598A Expired - Fee Related JP3522121B2 (en) | 1998-09-02 | 1998-09-02 | electronic microscope |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3522121B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2056332A1 (en) * | 2007-10-29 | 2009-05-06 | Hitachi High-Technologies Corporation | Displacement correction of a sample stage for an eucentric rotation in a charged particle microscope |
| JP2017208285A (en) * | 2016-05-20 | 2017-11-24 | 株式会社日立ハイテクノロジーズ | Charged particle beam device |
| JP2020042957A (en) * | 2018-09-10 | 2020-03-19 | 日本電子株式会社 | Electron microscope and adjustment method of electron microscope |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6394544A (en) * | 1986-10-08 | 1988-04-25 | Hitachi Ltd | Electron microscope |
| JPH04192244A (en) * | 1990-11-27 | 1992-07-10 | Hitachi Ltd | Electron microscope |
-
1998
- 1998-09-02 JP JP24817598A patent/JP3522121B2/en not_active Expired - Fee Related
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6394544A (en) * | 1986-10-08 | 1988-04-25 | Hitachi Ltd | Electron microscope |
| JPH04192244A (en) * | 1990-11-27 | 1992-07-10 | Hitachi Ltd | Electron microscope |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2056332A1 (en) * | 2007-10-29 | 2009-05-06 | Hitachi High-Technologies Corporation | Displacement correction of a sample stage for an eucentric rotation in a charged particle microscope |
| US7863564B2 (en) | 2007-10-29 | 2011-01-04 | Hitachi High-Technologies Corporation | Electric charged particle beam microscope and microscopy |
| JP2017208285A (en) * | 2016-05-20 | 2017-11-24 | 株式会社日立ハイテクノロジーズ | Charged particle beam device |
| JP2020042957A (en) * | 2018-09-10 | 2020-03-19 | 日本電子株式会社 | Electron microscope and adjustment method of electron microscope |
| JP7114417B2 (en) | 2018-09-10 | 2022-08-08 | 日本電子株式会社 | Electron Microscope and Electron Microscope Adjustment Method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3522121B2 (en) | 2004-04-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5296413B2 (en) | Cross-sectional image acquisition method using composite charged particle beam apparatus and composite charged particle beam apparatus | |
| JP2877624B2 (en) | Objective lens alignment control apparatus and control method for scanning electron microscope | |
| JP2010139890A (en) | Imaging apparatus | |
| JP2007179753A (en) | Scanning transmission electron microscope, and aberration measuring method | |
| JP5603421B2 (en) | Charged particle beam equipment with automatic aberration correction method | |
| CN104995905A (en) | Image processing device, photographing control method, and program | |
| JP6537231B2 (en) | Image processing apparatus, image processing method and program | |
| CN107302668A (en) | High dynamic range imaging module based on runner dynamic light splitting | |
| DE102018118620A1 (en) | Image pickup device and control method of this | |
| JPH073774B2 (en) | electronic microscope | |
| JPH04319236A (en) | Correction of pincushion distortion of x-ray image diagnostic device | |
| JP3522121B2 (en) | electronic microscope | |
| US20030183762A1 (en) | Method of observing a sample by a transmission electron microscope | |
| JP4891788B2 (en) | Electron microscope image distortion correction method and brightness correction method | |
| JPH0313700B2 (en) | ||
| JP4095743B2 (en) | Transmission electron microscope | |
| JPH04192244A (en) | Electron microscope | |
| JP2008226742A (en) | Image forming method and electron microscope | |
| JPH07302564A (en) | Scanning electron microscope | |
| JPH03182976A (en) | Joining method for digital picture | |
| US20050167607A1 (en) | Multipole field-producing apparatus in charged-particle optical system and aberration corrector | |
| JP2000323081A (en) | Electron microscope | |
| JP4634324B2 (en) | Transmission electron microscope | |
| JP2946857B2 (en) | Charged particle beam equipment | |
| JP2004146192A (en) | Test piece observation method by transmission electron microscope |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20040113 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20040130 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20040203 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090220 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100220 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110220 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110220 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120220 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130220 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130220 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140220 Year of fee payment: 10 |
|
| LAPS | Cancellation because of no payment of annual fees |