arrt review: image production (CR v. direct DR v. indirect DR)

Question 1

CR plate layers in order

Answer 1

Protective
Phosphor (active) = PSP
Conductive
Support/base
Reflective (light shield)
Backing (“Protective backing”)

Question 2

CR plate layers mnemonic

Answer 2

PPCSRB

People Prefer Chocolate Sauce, Really Bad

Question 3

active component of the CR plate

Answer 3

PSP (phosphorstimuable phosphor)

Question 4

____________ layer of CR plate grounds plate and reduces electrostatic charge

Answer 4

conductive

Question 5

___________ layer of CR plate directs emitted light

Answer 5

Reflective (light shield)

Question 6

PSP layer can ___________energy

Answer 6

store and release

Question 7

material in CR plates

Answer 7

barium fluorohalide bromides and iodides with europium activators

Question 8

material in DR indirect plates

Answer 8

amorphous silicon

Question 9

material in DR direct plates

Answer 9

amorphous selenium

Question 10

indirect DR steps (general)

Answer 10

x-rays –> visible light –> electronic signals

Question 11

direct DR steps (general)

Answer 11

x-rays –> electronic signals

Question 12

indirect DR
CCD versus TFT; what components make up the processing?

Answer 12

CCD = scintillation layer –> CCD –> ADC
TFT = scintillation layer –> photodiode –> TFT –> ADC

Question 13

fill factor = ___________ of _______ devoted to the semiconductor detection layer

Answer 13

percent, DEL

Question 14

higher DEL fill factor = (lower/higher) spatial resolution and (lower/higher) contrast resolution

Answer 14

higher, higher

Question 15

direct DR layers

Answer 15

photoconductor –> TFT –> ADC

Question 16

scintillation layer converts ______ to ______

Answer 16

x-rays to light

Question 17

do direct DR systems use scintillation layers?

Answer 17

no (only indirect DR use scintillation layers)

Question 18

scanning pattern of CR pattern

Answer 18

raster pattern

Question 19

what is the color of the laser in CR processing?

Answer 19

red

Question 20

what color light is emitted in CR processing?

Answer 20

blue or violet layer

Question 21

what is the role of the photomultiplier?

Answer 21

Converts small amounts of light into an exemplified electrical signal

Question 22

what does the analog to digital converter (ADC) do in CR processing?

Answer 22

converts the electrical signal from the photomultiplier tube into a digital signal

Question 23

how is the CR plate erased?

Answer 23

bright white light

Question 24

Slow scan = ______________________
fast scan = _________________

Answer 24

drive mechanism in the reader; movement of laser

Question 25

some CR systems use _____ instead of photomultiplier tubes

Answer 25

charged coupled devices

Question 26

CR processing energy transfer process = ______________________

Answer 26

photoelectric absorption

Question 27

(smaller/bigger) DELs give you better spatial resolution

Answer 27

Smaller

Question 28

Do we want a small matrix or a large matrix?

Answer 28

large matrix

Question 28

most common matrix in x-ray

Answer 28

1024x1024

Question 29

when you increase matrix size, pixel size (increases/decreases) spatial resolution (increases/decreases)

Answer 29

pixel size decreases, spatial resolution increases

Question 30

Total number of possible brightness levels (shades of gray) that can be assign to the digital image

Answer 30

bit depth

Question 31

is 12 bit or 16 bit preferred?

Answer 31

16 bit gives more shades of gray

Question 32

Process of assigning brightness levels

Answer 32

quantization

Question 33

larger bit depth increases ______________

Answer 33

contrast resolution

Question 34

how does saturation appear?

Answer 34

black

Question 35

how does mottle appear?

Answer 35

grainy

Question 36

what is the definition of dynamic range?

Answer 36

range of exposures that can be captured by an image receptor

Question 37

what is the definition of saturation?

Answer 37

intensity of radiation that is so high the computer cannot process it (beyond dynamic range of system)

Question 38

what is the definition of exposure latitude?

Answer 38

range of exposures that can produce quality images at an appropriate patient dose

Question 39

cesium iodide can be formed into _______ which focus (x-ray/light) photons

Answer 39

rods, light

Question 41

Small DEL = (big/small) pixel = (high/low) spatial resolution

Answer 41

Small pixel High spatial resolution