x-ray production Flashcards
memorized
roentgen discovered x-rays while working with an Crookes tube
Crookes
An electron cloud surrounding the filament of the cathode is referred to as space charge
space charge
the creation of the space charge in the x-ray tube produces
thermonic emission
The majority of photons in the x-ray beam are created by which process?
Brems
more than 99 of the energy of the electron stream is converted into : HEAT
Heat
The high-speed rotation (100,000 rpm) of the anode enables
greater dissipation of heat from high technical factors.
The degree of angulation of the x-ray tube target will determine the
size of the actual focal spot and effective focal spot
A dual focus x-ray tube
- two filaments
2.two focal spot sizes
the anode heel effect is a phenomenon of x-ray production that results in :
uneven distribution of radiation within the x-ray field.
The penetrating power of the x-ray beam is controlled by varying the KVP
peak kilovoltage
The rate of current flow across the x-ray tube is measured in
mA
doubling the mA will result in:
- increased patient dose 2. twice as many photons in the x-ray beam 3. increased radiographic density
the unit used to indicate the total quantity of x-ray exposure is :
(MAS)
the device for removing long wavelength radiation from the primary x-ray beam is the
filter
x-ray equipment capable of producing 70 kvp or more is required to have total filtration of at least
2.5 MM AI equiv.
The purpose of rotating the anode of the x-ray tube is to :
increase the heat capacity of the anode
image sharpness is determined by the
size of the effective focal spot
above 70 kvp what percentage of photons is created by the Bremsstrahlung process
85 percent
the amount of detail seen in the x-ray image is referred to as
spatial resolution
what is the percentage of characteristic radiation that is produced below 70 kvp ?
none . characteristic radiation can only be produced above 70 kvp.
the primary purpose of filtration is to
reduce patient dose
the filament is made of
tungsten
target and the anode are made of
tungsten
what is added to the port to remove the long wavelength radiation
aluminium
what type of motor is used to turn the anode inside the x-ray tube
induction motor
larger focal spot used -
larger patients or thick and dense body parts
all of the following devices are located within the low voltage circuit and control console except the : kilovolt control, exposure switch , autotransformer
step up transformer
