RTE 1401 Final Exam Questions & Answers 2025/2026
Fixed mAs/ variable kVp chart - (answer)adjust kVp by multiplying by 2 (+/-) for every increment of ONE
centimeter or inch of size difference
Fixed KVP/ variable mAs chart - (answer)adjust mAs by multiplying (+) by 2 for every 4-5 centimeter or
inch size difference
digital image quality factors - (answer)brightness, contrast resolution, spatial resolution, distortion
exposure indicator, noise
brightness - (answer)intensity of light coming through monitor
contrast resolution - (answer)how well a system can display varying shades of gray
-affected by dynamic range
pixel depth - (answer)determines the number of shades of gray that can be displayed: 2 to the 14th
power= 16,384 shades of gray
spatial resolution - (answer)measured in Lp/ mm
-2.5- 5 Lp/mm in digital imaging
distortion - (answer)size & shape
effected by SID, OID, and alignment
exposure indicator - (answer)number displayed on the processed image to indicate the level of x-ray
exposure received to the digital image receptor.
-red, yellow or green
noise - (answer)random disturbance that reduces of obscures image clarity
,RTE 1401 Final Exam Questions & Answers 2025/2026
-SNR and quantum noise
Signal to Noise Ratio (SNR) - (answer)The ratio of the speech signal (intended signal) to that of the
background noise
-HIGH is ALWAYS best
quantum noise - (answer)lack of sufficient data (photons) - results in blotchy or mottled image. Increase
mAs to fix
algorithms - (answer)complex math equations used to maintain image quality
Dynamic range - (answer)range of shades a digital system is capable of displaying as seen by the human
eye
exposure latitude - (answer)the range of exposures that can be used and still result in the capture of a
diagnostic-quality image
-DR has more than film-screen imaging
scotopic vision - (answer)night vision; uses rods of retina which are peripherally located
photopic vision - (answer)daylight vision; uses cones, centrally located
Image Intensifier - (answer)an electronic vacuum tube that converts beam of light to electrons, then
back to light, increasing the light intensity in the process
-brightens image up to 5,000 times brighter than conventional floural
-5 principal parts
5 principal parts of Image Intensifier - (answer)input phosphor screen, photocathode, electrostatic
focusing lenses, accelerating anode*, output phosphor screen
,RTE 1401 Final Exam Questions & Answers 2025/2026
Dead man's switch - (answer)apply positive pressure to switch (not constant power)
input phosphor screen - (answer)a 6"- 23" screen bonded to the curved surface of the flourscopy tube
-made of cesium iodide which acts as a scintillator
-converts XR to light
-curved to maintain distance to focal point
photocathode - (answer)emits e- when stimulated by light in a process called photoemission due to it
being made of cesium and antimony compounds
-bonded directly to input phospher
electrostatic focusing lenses - (answer)negatively charged plates that repel the e- to accelerate and
focus them
-gradient in operation
output phosphor screen - (answer)2.5 cm screen located at the opposite end of the image intensifier
that converts e- to intensified light
-made of zinc cadmium sulfide
accelerating anode* - (answer)located at the neck of the intensifier near output phospher, it sets the e-
stream in motion at a constant velocity
Multifield Image Intensifier - (answer)multiple sizes of input screen; may be used to magnify the image
Flux Gain - (answer)Ratio of the number of light photons at the output phosphor to the number of x-rays
at the input phosphor
, RTE 1401 Final Exam Questions & Answers 2025/2026
Minification Gain - (answer)Ratio of the square of the diameter of the input phosphor to the square of
the diameter of the output phosphor.
Total Brightness Gain - (answer)is equal to the product of Minification Gain and Flux Gain.
MG x FG
Tube failure reasons - (answer)1. Single high-heat exposure on cold anode
2. Tungsten vaporizing
3. Consecutive high heat exposures or long exposure times
Heat Units (HU) - (answer)kVp × ma × sec. × rectification constant (RC)
Rectification constant (generator type) - (answer)-Single phase= 1
-3 phase, 6 pulse= 1.35
-3phase, 12 pulse= 1.41
-high frequency= 1.45
Radiographic charts (3) - (answer)-tube rating chart
-anode cooling chart
-housing cooling chart
Tube rating chart - (answer)Used to determine if a given set of exposure factors are safe or unsafe
Anode cooling chart - (answer)Used to determine how long the anode will take to cool when heated
Housing cooling chart - (answer)Determines how long the housing will take to cool when heated
Fixed mAs/ variable kVp chart - (answer)adjust kVp by multiplying by 2 (+/-) for every increment of ONE
centimeter or inch of size difference
Fixed KVP/ variable mAs chart - (answer)adjust mAs by multiplying (+) by 2 for every 4-5 centimeter or
inch size difference
digital image quality factors - (answer)brightness, contrast resolution, spatial resolution, distortion
exposure indicator, noise
brightness - (answer)intensity of light coming through monitor
contrast resolution - (answer)how well a system can display varying shades of gray
-affected by dynamic range
pixel depth - (answer)determines the number of shades of gray that can be displayed: 2 to the 14th
power= 16,384 shades of gray
spatial resolution - (answer)measured in Lp/ mm
-2.5- 5 Lp/mm in digital imaging
distortion - (answer)size & shape
effected by SID, OID, and alignment
exposure indicator - (answer)number displayed on the processed image to indicate the level of x-ray
exposure received to the digital image receptor.
-red, yellow or green
noise - (answer)random disturbance that reduces of obscures image clarity
,RTE 1401 Final Exam Questions & Answers 2025/2026
-SNR and quantum noise
Signal to Noise Ratio (SNR) - (answer)The ratio of the speech signal (intended signal) to that of the
background noise
-HIGH is ALWAYS best
quantum noise - (answer)lack of sufficient data (photons) - results in blotchy or mottled image. Increase
mAs to fix
algorithms - (answer)complex math equations used to maintain image quality
Dynamic range - (answer)range of shades a digital system is capable of displaying as seen by the human
eye
exposure latitude - (answer)the range of exposures that can be used and still result in the capture of a
diagnostic-quality image
-DR has more than film-screen imaging
scotopic vision - (answer)night vision; uses rods of retina which are peripherally located
photopic vision - (answer)daylight vision; uses cones, centrally located
Image Intensifier - (answer)an electronic vacuum tube that converts beam of light to electrons, then
back to light, increasing the light intensity in the process
-brightens image up to 5,000 times brighter than conventional floural
-5 principal parts
5 principal parts of Image Intensifier - (answer)input phosphor screen, photocathode, electrostatic
focusing lenses, accelerating anode*, output phosphor screen
,RTE 1401 Final Exam Questions & Answers 2025/2026
Dead man's switch - (answer)apply positive pressure to switch (not constant power)
input phosphor screen - (answer)a 6"- 23" screen bonded to the curved surface of the flourscopy tube
-made of cesium iodide which acts as a scintillator
-converts XR to light
-curved to maintain distance to focal point
photocathode - (answer)emits e- when stimulated by light in a process called photoemission due to it
being made of cesium and antimony compounds
-bonded directly to input phospher
electrostatic focusing lenses - (answer)negatively charged plates that repel the e- to accelerate and
focus them
-gradient in operation
output phosphor screen - (answer)2.5 cm screen located at the opposite end of the image intensifier
that converts e- to intensified light
-made of zinc cadmium sulfide
accelerating anode* - (answer)located at the neck of the intensifier near output phospher, it sets the e-
stream in motion at a constant velocity
Multifield Image Intensifier - (answer)multiple sizes of input screen; may be used to magnify the image
Flux Gain - (answer)Ratio of the number of light photons at the output phosphor to the number of x-rays
at the input phosphor
, RTE 1401 Final Exam Questions & Answers 2025/2026
Minification Gain - (answer)Ratio of the square of the diameter of the input phosphor to the square of
the diameter of the output phosphor.
Total Brightness Gain - (answer)is equal to the product of Minification Gain and Flux Gain.
MG x FG
Tube failure reasons - (answer)1. Single high-heat exposure on cold anode
2. Tungsten vaporizing
3. Consecutive high heat exposures or long exposure times
Heat Units (HU) - (answer)kVp × ma × sec. × rectification constant (RC)
Rectification constant (generator type) - (answer)-Single phase= 1
-3 phase, 6 pulse= 1.35
-3phase, 12 pulse= 1.41
-high frequency= 1.45
Radiographic charts (3) - (answer)-tube rating chart
-anode cooling chart
-housing cooling chart
Tube rating chart - (answer)Used to determine if a given set of exposure factors are safe or unsafe
Anode cooling chart - (answer)Used to determine how long the anode will take to cool when heated
Housing cooling chart - (answer)Determines how long the housing will take to cool when heated
