Image-plane alcove reflection hologram using one-step recording

Computer programs are now available in various laboratories for the indexing and simulation of transmission electron diffraction patterns. Although these programs address themselves to the solution of various aspects of the indexing and simulation process, the ultimate goal is to perform real time diffraction pattern analysis directly off of the imaging screen of the transmission electron microscope. The program to be described in this paper represents one step prior to real time analysis. It involves the combination of two programs, described in an earlier paper(l), into a single program for use on an interactive basis with a minicomputer. In our case, the minicomputer is an INTERDATA 70 equipped with a Tektronix 4010-1 graphical display terminal and hard copy unit.A simplified flow diagram of the combined program, written in Fortran IV, is shown in Figure 1. It consists of two programs INDEX and TEDP which index and simulate electron diffraction patterns respectively. The user has the option of choosing either the indexing or simulating aspects of the combined program.

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Measurements in 3D images

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100086349 ◽

1991 ◽

Vol 49 ◽

pp. 408-409

Author(s):

John C. Russ

Keyword(s):

Three Dimensional ◽

Image Plane ◽

X Rays ◽

Traditional Use ◽

3D Images ◽

Confocal Scanning Laser Microscope ◽

Hard Materials ◽

Depth Direction ◽

Confocal Scanning ◽

Confocal Scanning Laser

Three-dimensional (3D) images consisting of arrays of voxels can now be routinely obtained from several different types of microscopes. These include both the transmission and emission modes of the confocal scanning laser microscope (but not its most common reflection mode), the secondary ion mass spectrometer, and computed tomography using electrons, X-rays or other signals. Compared to the traditional use of serial sectioning (which includes sequential polishing of hard materials), these newer techniques eliminate difficulties of alignment of slices, and maintain uniform resolution in the depth direction. However, the resolution in the z-direction may be different from that within each image plane, which makes the voxels non-cubic and creates some difficulties for subsequent analysis.

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Comparison of Conventional and Electron Spectroscopic Imaging in the Fixed Beam Electron Microscope of Ordered Protein Arrays

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117443 ◽

1985 ◽

Vol 43 ◽

pp. 74-75

Author(s):

E. L. Buhle ◽

U. Aebi

Keyword(s):

Image Processing ◽

Electron Microscope ◽

High Resolution ◽

Image Plane ◽

Electron Spectroscopic Imaging ◽

Protein Arrays ◽

Beam Electron ◽

Average Unit ◽

Fixed Beam ◽

Energy Components

CTEM brightfield images are formed by a combination of relatively high resolution elastically scattered electrons and unscattered and inelastically scattered electrons. In the case of electron spectroscopic images (ESI), the inelastically scattered electrons cause a loss of both contrast and spatial resolution in the image. In the case of ESI imaging on the Zeiss EM902, the transmited electrons are dispersed into their various energy components by passing them through a magnetic prism spectrometer; a slit is then placed in the image plane of the prism to select the electrons of a given energy loss for image formation. The purpose of this study was to compare CTEM with ESI images recorded on a Zeiss EM902 of ordered protein arrays. Digital image processing was employed to analyze the average unit cell morphologies of the two types of images.

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The restoration of blurred electron micrographs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142529 ◽

1986 ◽

Vol 44 ◽

pp. 180-181

Author(s):

Bridget Carragher ◽

David A. Bluemke ◽

Michael J. Potel ◽

Robert Josephs

Keyword(s):

Cross Section ◽

Electron Micrographs ◽

Relative Motion ◽

Finite Thickness ◽

Image Plane ◽

Helical Axis ◽

Thin Sections ◽

Structural Details

We have investigated the feasibility of restoring blurred electron micrographs. Two related problems have been considered; the restoration of images blurred as a result of relative motion between the specimen and the image plane, and the restoration of images which are rotationally blurred about an axis. Micrographs taken while the specimen is drifting result in images which are blurred in the direction of motion. An example of rotational blurring arises in micrographs of thin sections of helical particles viewed in cross section. The twist of the particle within the finite thickness of the section causes the image to appear rotationally blurred about the helical axis. As a result, structural details, particularly at large distances from the helical axis, will be obscured.

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Electron holography of p-n junctions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100167330 ◽

1996 ◽

Vol 54 ◽

pp. 974-975

Author(s):

B.G. Frost ◽

D.C. Joy ◽

L.F. Allard ◽

E. Voelkl

Keyword(s):

Electron Beam ◽

Electron Microscope ◽

Field Emission ◽

Ccd Camera ◽

Image Plane ◽

Reference Wave ◽

Field Of View ◽

Control Mode ◽

Objective Lens ◽

Electron Holography

A wide holographic field of view (up to 15 μm in the Hitachi-HF2000) is achieved in a TEM by switching off the objective lens and imaging the sample by the first intermediate lens. Fig.1 shows the corresponding ray diagram for low magnification image plane off-axis holography. A coherent electron beam modulated by the sample in its amplitude and its phase is superimposed on a plane reference wave by a negatively biased Möllenstedt-type biprism.Our holograms are acquired utilizing a Hitachi HF-2000 field emission electron microscope at 200 kV. Essential for holography are a field emission gun and an electron biprism. At low magnification, the excitation of each lens must be appropriately adjusted by the free lens control mode of the microscope. The holograms are acquired by a 1024 by 1024 slow-scan CCD-camera and processed by the “Holoworks” software. The hologram fringes indicate positively and negatively charged areas in a sample by the direction of the fringe bending (Fig.2).

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