Development of Super Resolution Phase Electron Microscopy

超分辨率相位电子显微镜的发展

• 批准号: 10450037
• 负责人: TAKAI Yoshizo
• 金额: $ 2.94万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10450037/
• 关键词: Phase Electron Microscope; Defocus Image Modulation Processing; 3D Fourier Filtering; Spherical aberration Correction; Aberration-Free observation; Hollow Cone Illumination; Real-Time Correction; 実時間観察; 焦点位置変調型画像処理; 能動型画像処理; 非点収差補正; コマ収差補正; 超解

In a high-resolution transmission electron microscope, the influence of a spherical aberration which intrinsically remains in the conventional magnetic lenses disturbs the interpretation for the atomic structure directly from the observed images. Defocus image modulation processing (DIMP) is one of the most promising approaches for observing spherical aberration-free phase and amplitude images with a transmission electron microscope. Since DIMP is based on a bipolar weighted image integration of the observed defocus series, all the processing of DIMP is performed in real space without Fourier transform. Therefore, the method can be rather easily applied to real-time processing by using a method of irradiation time control of a primary electron beam during accelerating voltage modulation. We have developed a real-time DIMP-EM using accelerating voltage modulation, recently. The original DIMP has presumed the observation under axial illumination, but DIMP can be extended for hollow-cone … More illumination (HCI) to realize much higher resolution, which has been already confirmed in the experiment using an optical microscope. In the present research, DIMP has been extended to HCI using an electron microscope for the first time. The processed image showed 10% higher resolution than the information limit, resulting in the realization of super resolution phase electron microscope having higher resolution than its attainable resolution under axial illumination.As another method to achieve super resolution electron microscopy, three dimensional Fourier filtering method has been mathematically derived using a proposed three dimensional image formation theory. Phase and amplitude images with spherical aberration correction has been confirmed in experiments. In the results, the resolution of the reconstructed phase image was improved from Scherzer resolution limit to the information limit because of the correction of spherical aberration. The 3D Fourier filtering method can be also applied to correct comprehensive aberrations, such as astigmatic aberration and coma aberration. Less

在高分辨率透射电子显微镜中，传统磁透镜中固有的球差影响了直接从观察到的图像对原子结构的解释。离焦图像调制处理（DIMP）是利用透射电子显微镜观测无球差相位和振幅图像最有前途的方法之一。由于DIMP是基于观测离焦序列的双极加权图像积分，因此DIMP的所有处理都是在真实空间中进行的，而不需要进行傅里叶变换。因此，该方法可以很容易地应用于实时处理，通过在加速电压调制过程中使用一次电子束辐照时间控制的方法。最近，我们开发了一种使用加速电压调制的实时DIMP-EM。原来的DIMP只假定轴向照明下的观测，但DIMP可以扩展到空心锥，更大的照度（HCI）可以实现更高的分辨率，这已经在光学显微镜的实验中得到了证实。在本研究中，首次使用电子显微镜将DIMP扩展到HCI。处理后的图像分辨率比信息极限高10%，从而实现了超分辨率相控电子显微镜在轴向照明下的分辨率高于其可达到的分辨率。作为实现超分辨率电子显微镜的另一种方法，三维傅里叶滤波方法利用提出的三维成像理论进行了数学推导。通过实验验证了经球差校正后的相位和振幅图像。结果表明，由于球面像差的校正，重构相位像的分辨率由舍尔策分辨率极限提高到信息极限。三维傅里叶滤波方法还可用于校正像散像差和彗差等综合像差。少

项目成果

Y.Takai et al.: "Defocus Image Modulation Processing Electron Microscope : Dynamic Observation of Crystal Deformation"Proc.of the 7th Asia-Psific Electron Microscopy Conference. 1. 128-129 (2000)

Y.Takai等人：“散焦图像调制处理电子显微镜：晶体变形的动态观察”第七届亚洲电子显微镜会议论文集。

T.Kawasaki, Y.Takai, T.Ikuta and R.Shimizu: "Construction of local area electron diffraction pattern using through-focus images"Eighth Conference on Frontiers of Electron Microscopy in Materials Science of Electron Microscopy in Materials Science. 1. 100-

T.Kawasaki、Y.Takai、T.Ikuta 和 R.Shimizu：“使用离焦图像构建局部区域电子衍射图案”第八届材料科学电子显微镜前沿会议材料科学电子显微镜。

T.Ueda et al.: "Cross-sectional transmission electron microscopic observation of etch hillocks and etch pits in LiTa03 single crystal"Japan Journal Applied Physics. (submitted). (1999)

T.Ueda等：“LiTa03单晶中蚀刻小丘和蚀刻坑的横截面透射电子显微镜观察”日本应用物理杂志。

Y.Takai et al.: "Defocus image modulation processing electron microscope : Dynamic observation of crystal deformation"Proc.Of Asia-Pasific Electron Microscope. (Submitted). (2000)

Y.Takai等人：“散焦图像调制处理电子显微镜：晶体变形的动态观察”Proc.Of Asia-Pasific Electron Microscope。

Y.Takai, H.Utsuro, T.Kawasaki, Y.Kimura, T.Ikuta and R.Shimizu: "Real Time Defocus Image Modulation Processing Electron Microscope"Proc.of the 7th NIRIM Int. Symposium on Advanced Materials. 1. 65-66 (2000)

Y.Takai、H.Utsuro、T.Kawasaki、Y.Kimura、T.Ikuta 和 R.Shimizu：“实时散焦图像调制处理电子显微镜”Proc. of the 7th NIRIM Int.