X-ray Lab Technique

Low-Resolution (LR) mode is mostly used for texture and residual Y-stress analysis. For these measurements x-ray tube has to be operated in point focus.

In X-ray Lab LR measurements can be done using the following optics:

Incident Beam:

PreFIX Crossed Slit Collimator - X'Pert 1

Polycapillary X-ray Lens - X'Pert 2

Diffracted Beam:

Parallel Plate Collimator + Flat Graphite Monochromator - X'Pert 1

Parallel Plate Collimator - X'Pert 2

Triple Axis/Rocking Curve (TA/RC) attachment's RC part - X'Pert 1

Crossed Slit Collimator (CSC) combines a divergence slit and the beam width mask in one optical module. The divergence slit part is used to control the equatorial divergence of the incident beam. The beam mask part of the collimator controls the axial divergence of the incident beam.

Note:
There is no advantage of Philips X'Pert diffractometer when x-ray tube is in point focus mode. X-ray Mirror is used only in line focus. Therefore, it is recommended to use Philips MRD diffractometer for texture and Y-stress measurements.

w/2q scans can also be done in low resolution mode. However, it is not the best setup for this kind of measurement. It is recommended to use medium resolution mode.

Low Resolution applications and the required equipment

Application	Incident Beam Optics	Diffracted Beam Optics	Remarks	Notes
Texture Analysis	Crossed Slit Collimator	Parallel Plate Collimator	Point focus.	The incident x-ray beam must be completely accepted by the sample at all f and y settings at all 2q angles where the pole figures are recorded. No defocusing effects occur over a wide range of y tilts.
Texture Analysis	Crossed Slit Collimator	Receiving Slit part of TA/RC attachment	Point focus. Higher intensity.	Defocusing effects will appear in the diffraction pattern measured at the higher y tilt angles.
Y-stress Analysis	Crossed Slit Collimator	Parallel Plate Collimator	Point focus.	No defocusing effects occur over a wide range of y tilts.
Y-stress Analysis	Crossed Slit Collimator	Receiving Slit part of TA/RC attachment	Point focus. Higher intensity.	Defocusing effects will appear in the diffraction pattern measured at the higher y tilt angles.
w-2q scan, phase analysis	Crossed Slit Collimator	Parallel Plate Collimator	Point focus.	Background is reduced by flat graphite monochromator. Some Kb can be visible next to strong Ka diffraction peaks. Insensitive to sample roughness and misalignment.
w-2q scan, phase analysis	Crossed Slit Collimator	Receiving Slit part of TA/RC attachment	Point focus. Higher intensity.	High background. Kb is present.