Quiz C12/13 (Bush) & C21/22 (C&A) Flashcards
Computed radiography screens respond to radiation with ______________________.
photostimulable luminescence
A photostimulable phosphor in a metastable state will emit light ________________.
immediately, when stimulated by light, and over time
The computed radiography cassette is called a(n) ______________ receptor.
imaging
The photostimulable phosphor screen is handled in a ______________.
reader
The four steps of creating an image with computed radiography are ______________.
metastable state, stimulate, read, and erase
The output signal from the photostimulable phosphor plate is converted from analog to digital by the ________________.
computer controls
The principal source of noise in computed radiography is ____________________.
scatter radiation
With computed radiography the contrast is _______________________________.
constant regardless of radiation exposure
The computed radiography image has _____________________ compared to Screen film Radiography.
wide exposure latitude and improved contrast resolution
The laser beam must be less than 100 µm in diameter in order to maintain ________.
high spatial resolution
_____________ is prevented by flooding the erased imaging plate with bright light.
ghosting
T or F: The digital imaging plate can sit for some time out in the open after the erase cycle.
false
T or F: IPs should be used soon after the erase cycle has been completed.
true
Digital radiography is best described by which three elements?
capture, coupling, and collection
In Computed radiography, the visible image results when the _______________ is scanned by a laser beam.
photostimulable phosphor (PSP)
In digital radiography, the brightness of the image is determined by _______________.
pixel values
In CR, the capture element is the _____________.
photostimulable phosphor (PSP)
What is the most recent development in digital radiography image receptors?
direct capture solid state devices
In digital radiography, spatial resolution is improved with increased _____________.
matrix size
The dynamic range determines the degree of __________________ in the image.
contrast resolution
One advantage of DR over scanned projection radiography is __________________________.
shorter exposure time
T or F: Digital radiography is best described by three elements—capture, archiving, and storage.
false
T or F: CsI/CCD is an indirect DR process by which x-rays are converted first to light and then to an electronic signal.
true
T or F: CsI/a-Si is an indirect DR process by which x-rays are converted first to light and then to an electronic signal.
true
T or F: Spatial resolution in DR is pixel-unlimited.
false
