lesson 3

Question 1

contains phosphor to convert x-ray into light

Answer 1

intensifying screen

Question 2

the emission of light from the screen when stimulated by x-ray

Answer 2

luminescence

Question 3

phosphor ability to emit visible light during x-ray

Answer 3

fluorescence

Question 4

emission of light after x-ray exposure has been done

Answer 4

phosphorescence

Question 5

layers of IS

Answer 5

• protective coating
• phosphor
• reflective layer
• base

Question 6

three rare earth (green emission) elements

Answer 6

• gadolinium
• lanthanum
• yttrium

Question 7

high atomic number so that absorption is high

Answer 7

quantum detection efficiency

Question 8

emit a large amount of light per x-ray absorption

Answer 8

x-ray conversion efficiency

Question 9

light emitted must be proper wavelength (color) to match the sensitivity of the x-ray film

Answer 9

spectral matching

Question 10

continuing emission of light after exposure of the phosphor to x-rays

Answer 10

phosphor afterglow

Question 11

it intercepts light headed in other directions and redirects it to the film

Answer 11

reflective layer

Question 12

serves principally as mechanical support for the active phosphor layer

Answer 12

base

Question 13

describes how efficiently x-rays are converted to light

Answer 13

screen speed

Question 14

defines as the ratio of exposure required to produce the same object detail

Answer 14

intensification factor

Question 15

term use to describe the deterioration of a radiographic image

Answer 15

image noise

Question 16

refers to random nature by which x-rays interact with the image receptor

Answer 16

quantum mottle

Question 17

ability to produce an accurate and clear image of the screen

Answer 17

spatial resolution

Question 18

ability to image similar tissues such as liver and pancreas

Answer 18

contrast resolution

Question 19

consist of lead lines separated by interspaces of equal size

Answer 19

line-pair test

Question 20

rare earth phosphors efficiently convert xray into usable light

Answer 20

phosphor composition

Question 21

the thicker the phosphor layer, the higher the detective quantum efficiency

Answer 21

phosphor thickness

Question 22

the presence of a _ increases screen speed but also increases image blur

Answer 22

reflective layer

Question 23

to control the spread of light

Answer 23

dye

Question 24

larger individual phosphor crystals produce more light per x-ray interaction

Answer 24

crystal size

Question 25

higher crystal concentration results in higher screen speed

Answer 25

concentration of phosphor crystals

Question 26

an indication that the screen phosphor exhibits too much emission of light even after the stimulation of x-ray

Answer 26

screen lag test

Question 27

method use to check screen film contact

Answer 27

wire mesh test