Bruker VANTEC-1, User Manual

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Hardware Installation for the D8 ADVANCE VÅNTEC-1 Detector User Manual
4 - 28 M88-E01072
Align the air scatter screen:
The alignment of the air scatter screen is depen-
dant upon the beam path of the system and the
type of optics used. The alignment consists of
two parts: the height of the paddle above the
sample surface and centering the paddle to the
center of the measuring circle. Because the
sample holder is mounted onto the stage in the
center of the goniometer, a fluorescent screen is
used as a reference to the center line. The
beam path of a Bragg-Brentano, para-focusing
or parallel beam (Göbel mirror) condition will
influence the gap between the paddle and the
sample surface.
1. Before any alignment is made to the air
scatter screen, run a measurement scan
using the settings in Table 7.1 or Table 7.2.
This data file will be the baseline for com-
parison to the data collected using the air
scatter screen. The baseline data should be
collected with a standard reference material
(SRM) like the NIST 1976 corundum plate.
See the Instrument Verification Booklet
M88-Zxx041 for additional system parame-
ters.
2. For the tilt and translation adjustments, use
a 2 mm Allen tool.
Perform manual alignment:
1. Run a measurement with predefined optical
settings with SRM1976 or another similar
reference material to define the intensity
distribution (see M88-Zxx041).
2. Move the primary (theta or tube) drive to 0°
theta.
3. Mount the fluorescent screen (P/N A13-
B71) onto the sample stage.
3.1 Set tilt to a reasonable value (see item
5 in Figure 4.28).
3.2 Align the height of the gap between the
paddle and the sample surface using
tilt.
3.3 For a 0.6 mm (0.3°) divergence slit, use
a gap of 2 mm as a starting point.
4. Align the translation of the screen so the
paddle will be exactly centered to the sam-
ple (see Figure 4.29).
5. Repeat the measurement in step 1 and
check the intensity distribution.
6. Close the height of the gap and realign the
translation to keep the paddle centered.
6.1 Repeat steps 5 and 6 until the desired
intensity distribution is met. Do not for-
get to compensate the translation
movement of the air scatter screen.