The effect of exit beam phase aberrations on parallel beam coherent x-ray reconstructions

A second generation twin lens has been developed. This symmetrical lens with a wider bore, yet superior values of chromatic and spherical aberration for a given focal length, retains both eucentric ± 60° tilt movement and 20°x ray detector take-off angle at 90° to the tilt axis. Adjust able tilt axis height, as well as specimen height, now ensures almost invariant objective lens strengths for both TEM (parallel beam conditions) and STEM or nano probe (focused small probe) modes.These modes are selected through use of an auxiliary lens situ ated above the objective. When this lens is on the specimen is illuminated with a parallel beam of electrons, and when it is off the specimen is illuminated with a focused probe of dimensions governed by the excitation of the condenser 1 lens. Thus TEM/STEM operation is controlled by a lens which is independent of the objective lens field strength.

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Quantitative determination of polymorphic composition in intact compacts by parallel-beam X-ray powder diffractometry II

Journal of Pharmaceutical and Biomedical Analysis ◽

10.1016/j.jpba.2005.03.003 ◽

2005 ◽

Vol 39 (1-2) ◽

pp. 1-7 ◽

Cited By ~ 20

Author(s):

Peter L.D. Wildfong ◽

Nicole A. Morley ◽

Michael D. Moore ◽

Kenneth R. Morris

Keyword(s):

Quantitative Determination ◽

Parallel Beam ◽

X Ray ◽

Polymorphic Composition

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Inversion of the X-ray transform from limited angle parallel beam region of interest data with applications to electron tomography

PAMM ◽

10.1002/pamm.200700762 ◽

2007 ◽

Vol 7 (1) ◽

pp. 1050301-1050302

Author(s):

Ozan Ã–ktem ◽

Eric Todd Quinto

Keyword(s):

Electron Tomography ◽

Region Of Interest ◽

Parallel Beam ◽

X Ray ◽

Ray Transform ◽

Limited Angle

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X-ray Diffraction Studies of Polycrystalline Thin Films Using Glancing Angle Diffractometry

Advances in X-ray Analysis ◽

10.1154/s0376030800020620 ◽

1988 ◽

Vol 32 ◽

pp. 311-321 ◽

Cited By ~ 2

Author(s):

R.A. Larsen ◽

T.F. McNulty ◽

R.P. Goehner ◽

K.R. Crystal

Keyword(s):

Thin Films ◽

Deep Penetration ◽

X Ray Diffraction ◽

Parallel Beam ◽

X Ray ◽

Beam Geometry ◽

Polycrystalline Thin Films ◽

Glancing Angle ◽

Parallel Beam Geometry

AbstractThe use of conventional θ/2θ diffraction methods for the characterization of polycrystalline thin films is not in general a satisfactory technique due to the relatively deep penetration of x-ray photons in most materials. Glancing incidence diffraction (GID) can compensate for the penetration problems inherent in the θ/2θ geometry. Parallel beam geometry has been developed in conjunction with GID to eliminate the focusing aberrations encountered when performing these types of measurements. During the past yearwe developed a parallel beam attachment which we have successfully configured to a number of systems.

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Visualization of Liquid Water Distribution at Interfaces of PEFC by Using Parallel-Beam Soft X-ray Radiography

ECS Meeting Abstracts ◽

10.1149/ma2017-02/32/1435 ◽

2017 ◽

Keyword(s):

Liquid Water ◽

Water Distribution ◽

Parallel Beam ◽

X Ray

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X-ray Residual Stress Measurements Using Parallel Beam Optics

Advances in X-ray Analysis ◽

10.1154/s037603080001199x ◽

1976 ◽

Vol 20 ◽

pp. 393-402 ◽

Cited By ~ 2

Author(s):

Richard M. Chrenko

Keyword(s):

Residual Stress ◽

Grain Size ◽

Beam Optics ◽

X Ray Diffraction ◽

Parallel Beam ◽

Modes Of Operation ◽

X Ray ◽

Stress Measurements ◽

Larger Sample ◽

Special Modes

X-ray residual stress measurements have been made with a commercial portable X-ray diffraction apparatus that uses parallel beam optics and that was specifically designed for residual stress measurements. This machine differs from X-ray diffraction units using the usual parafocusing geometry in several respects, most notably reduced sample placement errors and larger sample sizes that can be accommodated. Two special modes of operation are available and will be discussed. These are the ability to use the side inclining method for stress analysis and the ability to use an oscillating ψ motion, the latter mode being useful for examining large grain size materials.

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