Quiz C12/13 (Bush) & C21/22 (C&A)

Question 1

Computed radiography screens respond to radiation with ______________________.

Answer 1

photostimulable luminescence

Question 2

A photostimulable phosphor in a metastable state will emit light ________________.

Answer 2

immediately, when stimulated by light, and over time

Question 3

The computed radiography cassette is called a(n) ______________ receptor.

Answer 3

imaging

Question 4

The photostimulable phosphor screen is handled in a ______________.

Answer 4

reader

Question 5

The four steps of creating an image with computed radiography are ______________.

Answer 5

metastable state, stimulate, read, and erase

Question 6

The output signal from the photostimulable phosphor plate is converted from analog to digital by the ________________.

Answer 6

computer controls

Question 7

The principal source of noise in computed radiography is ____________________.

Answer 7

scatter radiation

Question 8

With computed radiography the contrast is _______________________________.

Answer 8

constant regardless of radiation exposure

Question 9

The computed radiography image has _____________________ compared to Screen film Radiography.

Answer 9

wide exposure latitude and improved contrast resolution

Question 10

The laser beam must be less than 100 µm in diameter in order to maintain ________.

Answer 10

high spatial resolution

Question 11

_____________ is prevented by flooding the erased imaging plate with bright light.

Answer 11

ghosting

Question 12

T or F: The digital imaging plate can sit for some time out in the open after the erase cycle.

Answer 12

false

Question 13

T or F: IPs should be used soon after the erase cycle has been completed.

Answer 13

true

Question 14

Digital radiography is best described by which three elements?

Answer 14

capture, coupling, and collection

Question 15

In Computed radiography, the visible image results when the _______________ is scanned by a laser beam.

Answer 15

photostimulable phosphor (PSP)

Question 16

In digital radiography, the brightness of the image is determined by _______________.

Answer 16

pixel values

Question 17

In CR, the capture element is the _____________.

Answer 17

photostimulable phosphor (PSP)

Question 18

What is the most recent development in digital radiography image receptors?

Answer 18

direct capture solid state devices

Question 19

In digital radiography, spatial resolution is improved with increased _____________.

Answer 19

matrix size

Question 20

The dynamic range determines the degree of __________________ in the image.

Answer 20

contrast resolution

Question 21

One advantage of DR over scanned projection radiography is __________________________.

Answer 21

shorter exposure time

Question 22

T or F: Digital radiography is best described by three elements—capture, archiving, and storage.

Answer 22

false

Question 23

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.

Answer 23

true

Question 24

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.

Answer 24

true

Question 25

T or F: Spatial resolution in DR is pixel-unlimited.

Answer 25

false