ThermoFisher Scientific EZx, User Manual

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About this Manual
Thermo Fisher Scientific About this Manual ix
REC 4132 Rev E
The principle constituents of an
X-ray
tube are:
•
Glass Envelope
– provides a vacuum for the electron beam
•
Electron Source
– a filament, which operates at a high temperature.
The current through the filament provides control on the quantity of
the electrons emitted.
•
High Voltage
– applied between the filament (the cathode) and the
anode. This high voltage controls the
X-ray
power, and the force of
the penetration of the
X-ray
s.
•
Anode
– a piece of metal (typically tungsten) that is hit by the
electrons.
The entire tube is immersed in oil, shielded in lead, and contained in a
tank. This ensures the
X-ray
s are contained within the tank, except for a
controlled beam used for detection.
The oil is there to cool the tube because of the heat produced and helps
insulate the high voltage within the tank.
This section discusses the properties of
X-ray
s.
X-ray
s are capable of penetrating through dense materials. The depth of
penetration is determined by the density of the material, together with
the high voltage applied to the tube. The depth of penetration is
important, because it permits differences in product densities to be
shown.
Properties of
X-ray
s
Absorption of
X-ray
s
Detector
Product
X-Ray Source
Conveyor