Xray System

Question 1

what are the 3 principal parts of the imaging system

Answer 1

xray tube
high voltage generator
operating console

Question 2

what does the operating console control

Answer 2

tube current -mA
voltage -kVp
exposure time - ms

Question 3

function of line compensator

Answer 3

measures voltage provided and adjust the voltage precisely to 220V

Question 4

where is the first stop of power in the imaging system and where does it deliver the power

Answer 4

first delivered to the autotransformer who then delivers the precise voltage to the filament circuit and high voltage circuit

Question 5

what is the role of the filament curcuit?

Answer 5

determines how many photons will be in the beam -mA

Question 6

what is the role of the high voltage circuit

Answer 6

determines the potential difference across the xray tube -kVp

Question 7

what determines the number of electrons emitted by the filament?

Answer 7

heat and current

current will control temp of filament

Question 8

in order to increase the number of electrons that reach the image receptor without increasing mA you would increase the ________ of _______

Answer 8

time of exposure

Question 9

what is AEC, what does it do

Answer 9

automatic exposure control
with ionization chambers or photodiode detectors they measure the amount of radiation that reaches the image receptor and terminates exposure when there is sufficient exposure to achive the appropriate optical density on the image

Question 10

what is the role of the high voltage generator

Answer 10

converts low voltage into the kilovoltage energy range

Question 11

what are the three primary parts of the high voltage generator?

Answer 11

high voltage transformer
filament transformer
rectifiers

Question 12

what are rectifiers used for

Answer 12

convert alternating current to direct current

Question 13

for solid state rectifiers what charges need to be applied to the p and n side to make electrons flow

Answer 13

p -pos

n- neg

Question 14

what is half wave rectification

Answer 14

negative half of current cycle is removed only allowing current to flow during the positive part of the cycle
the negative half results in energy loss

Question 15

what is full wave rectification

Answer 15

• when negative half of the cycle is reversed so that the anode is always positive, no gaps in output waveform
• usually involves 2 diodes which conduct during the positive half cycle and 2 more conducting only during the negative half cycle