LRA 221 FINAL EXAM QUESTIONS
WITH CORRECT ANSWERS
Which statement best describes a capacitor? - ANSWER-It converts x-ray photons to
light and stores it.
Which of the following statements about scintillators is true? - ANSWER-The amount of
x-rays absorbed depends on the type of scintillator.
The readout process requires that _______ and _______. - ANSWER-the flow of
electrons is timed; multiple voltage changes occur
The most common types of noise that affects image quality include all of the following
except - ANSWER-quantum noise
When compared with a CMOS, CCDs: - ANSWER-use more than 100 times the power
The most popular base material used in integrated circuits is - ANSWER-Silicon
A highly efficient indirect conversion system that takes up less fill space than CCDs is
known as a(n) - ANSWER-CMOS
The indirect conversion detector system that requires optical coupling and image size
reduction is known as a - ANSWER-CCD
When specialized pixels in a complementary metal oxide silicon system are struck with
X-ray photons - ANSWER-all of the above
Quantum efficiency is a measurement of the - ANSWER-Amount of electrons produced
by relative to the incident light from the scintillator
Some advantages to CCDs include - ANSWER-A and C only
The number of electron-hole pairs produced is related to the amount of light absorbed. -
ANSWER-True
Film and intensifying screens are primarily used in - ANSWER-conventional radiography
, CR acquires an image through: - ANSWER-The use of a storage phosphor plate
Technologist efficiency ratings are generally the same when comparing conventional
radiography with ______ radiography. - ANSWER-computed
The active element in a storage phosphor is: - ANSWER-barium fluorohalide
In reference to PSP image capture, to release the latent image, which of the following
devices is scanned over the phosphor plate? - ANSWER-Focused laser light
X-ray energy related in indirect capture DR will stimulate a ______, which eventually is
changed into an electrical signal. - ANSWER-scintillator
The ______ converts x-ray energy directly to a digital electrical signal. - ANSWER-
photoconductor
Exposure latitude is to conventional radiography as _______ is to DR. - ANSWER-
dynamic range
A look-up table maps - ANSWER-Image gray scale values
All of the following are components of a PACS except - ANSWER-independent
kilovoltage peak and milliampere-second stations.
Similar to CR, DR can use the existing diagnostic equipment found in today's imaging
departments. - ANSWER-False- Can't use the same equipment
Indirect capture DR converts absorbed x-ray energy into visible light. - ANSWER-True-
indirect DR convert X-ray energy to visible light
DICOM is a standard that allows imaging modalities and PACS to communicate in the
same language. - ANSWER-True
Which of the following statements is not true? - ANSWER-Changing the matrix and the
FOV will not change the size of the pixel.
Each square in a matrix is called a - ANSWER-picture element
The number of bits per pixel is known as bit - ANSWER-depth
Which of the following statements is not true?? - ANSWER-Exposure index refers to the
amount of exposure to the patient.
Deviation index is the difference between _____ and _____ expressed in logarithmic
fashion. - ANSWER-actual exposure (KIND); target exposure (KTGT)
WITH CORRECT ANSWERS
Which statement best describes a capacitor? - ANSWER-It converts x-ray photons to
light and stores it.
Which of the following statements about scintillators is true? - ANSWER-The amount of
x-rays absorbed depends on the type of scintillator.
The readout process requires that _______ and _______. - ANSWER-the flow of
electrons is timed; multiple voltage changes occur
The most common types of noise that affects image quality include all of the following
except - ANSWER-quantum noise
When compared with a CMOS, CCDs: - ANSWER-use more than 100 times the power
The most popular base material used in integrated circuits is - ANSWER-Silicon
A highly efficient indirect conversion system that takes up less fill space than CCDs is
known as a(n) - ANSWER-CMOS
The indirect conversion detector system that requires optical coupling and image size
reduction is known as a - ANSWER-CCD
When specialized pixels in a complementary metal oxide silicon system are struck with
X-ray photons - ANSWER-all of the above
Quantum efficiency is a measurement of the - ANSWER-Amount of electrons produced
by relative to the incident light from the scintillator
Some advantages to CCDs include - ANSWER-A and C only
The number of electron-hole pairs produced is related to the amount of light absorbed. -
ANSWER-True
Film and intensifying screens are primarily used in - ANSWER-conventional radiography
, CR acquires an image through: - ANSWER-The use of a storage phosphor plate
Technologist efficiency ratings are generally the same when comparing conventional
radiography with ______ radiography. - ANSWER-computed
The active element in a storage phosphor is: - ANSWER-barium fluorohalide
In reference to PSP image capture, to release the latent image, which of the following
devices is scanned over the phosphor plate? - ANSWER-Focused laser light
X-ray energy related in indirect capture DR will stimulate a ______, which eventually is
changed into an electrical signal. - ANSWER-scintillator
The ______ converts x-ray energy directly to a digital electrical signal. - ANSWER-
photoconductor
Exposure latitude is to conventional radiography as _______ is to DR. - ANSWER-
dynamic range
A look-up table maps - ANSWER-Image gray scale values
All of the following are components of a PACS except - ANSWER-independent
kilovoltage peak and milliampere-second stations.
Similar to CR, DR can use the existing diagnostic equipment found in today's imaging
departments. - ANSWER-False- Can't use the same equipment
Indirect capture DR converts absorbed x-ray energy into visible light. - ANSWER-True-
indirect DR convert X-ray energy to visible light
DICOM is a standard that allows imaging modalities and PACS to communicate in the
same language. - ANSWER-True
Which of the following statements is not true? - ANSWER-Changing the matrix and the
FOV will not change the size of the pixel.
Each square in a matrix is called a - ANSWER-picture element
The number of bits per pixel is known as bit - ANSWER-depth
Which of the following statements is not true?? - ANSWER-Exposure index refers to the
amount of exposure to the patient.
Deviation index is the difference between _____ and _____ expressed in logarithmic
fashion. - ANSWER-actual exposure (KIND); target exposure (KTGT)
