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4.2.4 Detection system

Diffracted neutron beam from a sample object has to
be captured and recorded by detector and data ac-
quisition. In general, there are an analog or digital
approach to record and display diffraction data. Ana-
log approach was utilised radiographic film and recent
method is mainly utilised a digital method. Detection
can be done either in one dimensional using single lin-
ear detector or two dimensional using area detector.
Multiple arrangement of single detectors into two di-
mensional array provide similar to area detection sys-
tem as well.

However, detection system is dependent on the sam-
ple type, single detector is used for the sample in pow-
der form. Sample in randomly distributed or isotropic
usually can be used for diffraction system with single
detector. While, fibre sample where usually crystal
with some preferred orientation required large area de-
tector to capture its diffraction pattern. Furthermore, if
the interest is more on molecular orientation, the diffrac-
tion using area detection system is needed.

4.3 Neutron wavelength measurement

Monochromatic neutron beam is required in diffraction
experiment for residual stress measurement. It is ob-
tained by letting the neutron beam reflects by a ma-

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