Diagnostic Xray Production Flashcards
The effects of making the actual focal spot appear smaller when viewed from the position of the X-ray film
Line focus principle
What is the surface of the anode that is bombarded by the electron beam coming from the cathode?
Focal spot
Maximum electrical and thermal tube ratings for a portable, table top unit
60-90 kvp
40-120 kvp
If the angle of the anode is less than 15 degrees, the xray beam will be narrow and the image…
Will have good resolution
Thicker portion should be placed under which side of the X-ray tube
Cathode
The variation in intensity between the anode and cathode is
Heel effect
Most common cathode failure
Filament evaporation
Within an xray machine, what adjusts the incoming voltage so the primary voltage stays constant?
Line voltage compensator
Purpose of ground wire
Alternative route for energy when broken
X-ray machines have how many volts of energy running through them
220 v
Why are 3 phase generators more efficient than single and high frequency generators?
Target is not subjected to low energy electrons
What transformer provides a variable yet predetermined voltage to step up transformer
Autotransformer
Auto transformer is connected to what exposure factor?
Kvp exposure factor
What transformer boosts the incoming voltage to the X-ray tube
Step up
What is the step up transformers purpose?
Transport electron stream to anode
What transformer produces the correct temperature for the cathode filament by decreasing the voltage?
Step down transformer
The step down transformer is connected to what exposure factor?
mA exposure factor
High voltage circuit transformers
Auto and step up
Low voltage circuit
Step down transformer
Charge of cathode and anode
Cathode- neg
Anode- pos
what occurs during the partial depression of the exposure pedal?
initiate low voltage circuit, anode begins to spin
what occurs during the full depression of exposure pedal
initiates high voltage circuit, electrodes flow and produce xray
AC vs DC
AC- pos and neg deflection
DC- pos deflection
what currents do xray machines use?
DC
why is DC more beneficial to us?
allows for shorter exposure time. important bc of movement
switching between AC and DC currents is called?
rectification
what percent of heat is produced when the electrons strike the anode target?
99%
what percent of xrays are produced when the electrons strike the anode target?
1%
the cathode filament and the anode target are made from what metal?
tungsten
the focusing cup within the cathode is made from what metal?
molybdenum
to help dissipate and absorb heat, the anode target sits in a cylindrical base made of what material?
copper
what type of anode is used in small animal xray units?
rotating
ideal target would have what to equal out the heat
high kVp, low mA
