The traditional Debye-Scherrer and Hull diffractometer

The X-rays emitted by the Coolidge tube penetrate the cylindrical chamber on the axis of which is placed the sample. An imprint of the diffracted beams is produced using a film placed on the inside of the chamber. The intersection of the diffraction cones and the cylinder gives diffraction arcs with a curvature that depends on the angle. These arcs become hnes when 20 = 180° and their curvature is reversed beyond that. 

Two sample holders can be considered, but they must always be made of glass so as not to diffract the X-rays. 

In this case, the sample holder is made of fiberglass, which is as thin as possible, on which the powder we wish to study is deposited and glued using a thin layer of grease. 

This method, while relatively simple, has a drawback. The powder located on the edges of the fiber carmot be placed in exactly the center of the device, which widens the diffraction arcs. 

This time, the powder sample is placed inside a glass tube with very thin sides. The major problem of this sample holder is absorption, since the X-ray beam must go through the tube s walls and therefore be partially absorbed. Therefore, the capillary is made out of low absorbing material, in practice Lindemarm glass or silica. 

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