Film Screen

Question 1

Radiographic Processing

Chemical tanks, roller transport system and dryer

Answer 1

Automatic Processing

Question 2

What turns the image permanently visible or a manifest image?

Answer 2

Exposure of the silver bromide crystals in the emulsion by light or x-ray photons creates the latent image and initiates the conversion process

Question 3

Types of phosphors

Answer 3

• most common- some elements from rare earth group
• Rare earth elements (57-71 atomic # on periodic table)
• Rare earth absorbs more x-rays, then converts to visible light more efficiently

Question 4

Operate by process of luminescence- emission of light from screen when stimulated by radiation

Answer 4

• Florescence ability to emit visible light

* Phosphorescence screen phosphors continue to emit light after exposure ends, screen lag/after glow

Question 5

The protective layer is made up of what and protects what?

Answer 5

plastic

fragile phosphor

Question 6

What is the most important layer in the intensifying screens?

Answer 6

Phosphor or active layer- absorbs transmitted x-rays and converts them to visible light

Question 7

What layer reflects or absorb light

Answer 7

Reflecting or absorbing layer

Question 8

The bottom layer of the intensifying screens is what and made up of what?

Answer 8

Base
polyester or cardboard
provides support and stability for phosphor layer
(refer to Pg. 115 box 5.3 in fauber)

Question 9

Intensifying Screens

Answer 9

• placed in cassettes
• front screen tube; opposite is back screen
• double emulsion exposed to twice as much light as single emulsion due to both sides being exposed
• single screen is mounted as back screen opposite the tube side

Question 10

Ability of radiographic film to provide level of image contrast

Answer 10

Contrast
(high- more black and white areas)
(low- more shades of grey)

Question 11

What are the two categories of spectral sensitivity

Answer 11

blue sensitive and green sensitive

Question 12

Refers to color of light produced by the intensifying screen, blue and green light emitting

Answer 12

Spectral Emission

Question 13

Refers to correct match of film and screens

Answer 13

Spectral Matching

Question 14

Failure to match will result in what?

Answer 14

Suboptimal density

Question 15

What do intensifying screens do?

Answer 15

Convert x-rays images into light

Question 16

What chemical compound emits visible light when struck by radiation

Answer 16

phosphor

Question 17

Purpose of screens-

Answer 17

reduce radiation dose to patient - less mAs

Question 18

______ _______ is coated on both sides of the base with layer of supercoat and is used with two intensifying screens

Answer 18

Double Emulsion

Question 19

______ ________ coated with only one layer; used with single intensifying screen used for mammography?

Answer 19

Single Emulsion

Question 20

Characteristics of Single Emulsion

Answer 20

• Anticurl/antihalation layer is colored backing on single emulsion that prevents curling and halation
• halation is (light reflected back to expose the emulsion a second time)
• light reflected back comes from intensifying screen

Question 21

Sensitivity or speed affected by silver halide crystals in the emulsion both number and size of crystals;

Answer 21

As they increase film speed increases

Question 22

Film Characteristics

Answer 22

manufactures can manipulate speed with changes in the number and size of the crystals

Question 23

Image that exists on the film after exposure and processing- typically called radiographic image

Answer 23

Manifest Image

Question 24

What are the two general types of film

Answer 24

Direct exposure and screen film

Question 25

Characteristics of Direct exposure

Answer 25

* non screen film * single emulsion thicker than screen film requires more development time * requires more exposure may need manual processing, used for oral/dental imaging * Ready packs of radiation therapy film for port film localization may/may not be placed in cardboard cassette

Question 26

Characteristics of Scatter Film

Answer 26

* Used with one or two intensifying screens * more sensitive to light and less sensitive to radiation * emulsion layers thinner than direct exposure and require less development * requires less radiation exposure * can have single- double emulsion

Question 27

What effects the quality of the film?

Answer 27

Kvp

Question 28

What effects the quantity of the film?

Answer 28

mAs

Question 29

Film Screen Combination-

Answer 29

* film screen-systems are classified by RS factor * RS factor speed range from 50-800 * extremity film screen- 100 * routine high speed- 400

Question 30

Radiographic film used in a cassette with intensifying screens is the most common image receptor today

Answer 30

Double emulsion

Question 31

What does film record

Answer 31

the image produced by intensifying screens

Question 32

The rigid, light tight container that holds the screen and film in close contact

Answer 32

Cassette

Question 33

What are the layers of the film

Answer 33

Outside- supercoat, durable protective layer damage to sensitive emulsion layer Next layer- emulsion radiation and light sensitive layer- consist of silver halide crystals suspended in gelatin Final Layer

Question 34

What does the final layer in the base contain

Answer 34

a blue dye tint to reduce eye strain when viewing finished radiograph

Question 35

Image which exists on film after film has been exposed and before processing

Answer 35

latent image

Question 36

Silver Halide

Answer 36

Material that is sensitive to radiation and light, silver bromide (AgBr) and silver iodide make up the emulsion layer of the film

Question 37

AgBr

Answer 37

90-99%

Question 38

Agl

Answer 38

1-10%

Question 39

Exact formulation Proprietary Information

Answer 39

Business only- Super Secrete