Hemispherical Laue camera

Patent · Tue Jan 01 04:00:00 EST 1980

OSTI ID:863635

Li, James C. M. ^[1]; Chu, Sungnee G ^[2]

---

1. Pittsford, NY
2. Rochester, NY

A hemispherical Laue camera comprises a crystal sample mount for positioning a sample to be analyzed at the center of sphere of a hemispherical, X-radiation sensitive film cassette, a collimator, a stationary or rotating sample mount and a set of standard spherical projection spheres. X-radiation generated from an external source is directed through the collimator to impinge onto the single crystal sample on the stationary mount. The diffracted beam is recorded on the hemispherical X-radiation sensitive film mounted inside the hemispherical film cassette in either transmission or back-reflection geometry. The distances travelled by X-radiation diffracted from the crystal to the hemispherical film are the same for all crystal planes which satisfy Bragg's Law. The recorded diffraction spots or Laue spots on the film thereby preserve both the symmetry information of the crystal structure and the relative intensities which are directly related to the relative structure factors of the crystal orientations. The diffraction pattern on the exposed film is compared with the known diffraction pattern on one of the standard spherical projection spheres for a specific crystal structure to determine the orientation of the crystal sample. By replacing the stationary sample support with a rotating sample mount, the hemispherical Laue camera can be used for crystal structure determination in a manner previously provided in conventional Debye-Scherrer cameras.

• Research Organization: Rochester Univ., NY (USA)
• DOE Contract Number: EY-76-S-02-2296
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4217493
• OSTI ID: 863635
• Country of Publication: United States
• Language: English

Related Subjects

/378/
analyzed
back-reflection
beam
bragg
camera
camera comprises
cameras
cassette
center
collimator
compared
comprises
conventional
crystal
crystal orientation
crystal plane
crystal planes
crystal structure
debye-scherrer
determination
determine
diffracted
diffracted beam
diffraction
diffraction pattern
directed
directly
directly related
distances
exposed
external
external source
factors
film
film cassette
generated
geometry
hemispherical
hemispherical laue
impinge
information
inside
intensities
laue
laue camera
law
manner
mount
mounted
mounted inside
orientation
orientations
pattern
planes
positioning
preserve
previously
projection
provided
radiation generated
radiation sensitive
recorded
related
relative
replacing
rotating
sample
sample mount
satisfy
sensitive
sensitive film
set
single
single crystal
source
specific
sphere
spheres
spherical
spots
standard
stationary
structure
support
symmetry
transmission
travelled
x-radiation