Image Formation Flashcards
3 components of image formation
- Film
- Intensifying screen
- Cassette
Displays the radiograp;hic density
Film
The film is —, or capable of respending to exposure by photons
Photosensitive
The film is sensitive to the (1) and (2) that comprise most of the electromagnetic spectrum of both (3) and (4)
- wavelength
- energies
- light
- x-rays
Designed to be anti-static, which precent mark on the film (which can later cause misdiagnosis)
Overcoat
Other term for overcoat
Supercoat
Hard gelatin
Overcoat
Protects emulsion from scratches, pressure, and contamination during handling, processing, and storage
Overcoat
Overcoat protects emulsion from (1), (2), and (3) during (4), (5), and (6).
- scratches
- pressure
- contamination
- handling
- processing
- storage
Foundation of radiographic film
Base
Materials of choice for the base of an x-ray film
- Glass plate (before WWI)
- Cellulose nitrate: flammable
- Cellulose triacetate: “safety base”
- Polyester
Film base characteristics/ properties
- Flexible and tough
- Stable (Dimensional stability)
- Rigid
- Uniformly lucent
During manufacturing, a dye is added to the (1) of most radiographic film to slightly tint the film blue. This coloring reduces (2) and (3), enhancing the radiologis’s diagnostic (4) and accuracy.
- base
- eyestrain
- fatigue
- efficiency
Heart of the radiographic film
Emulsion
Material with which x-rays or light photons interact
Emulsion
The emulsion consists of a homogenous micture of (1) and (2)
- gelatin
- silver halide crystals
thickness of the emulsion
3-5 μm (micrometer) thick
It provides mechanical support for the silver halide crystals by holding them uniformly dispersed in place
Gelatin
Component of the emulsion that is clear and flexible
Gelatin
Porous for processing chemicals to penetrate
Gelatin
Active ingridient of the emulsion
Silver Halide Crystals
Silver Halide Crystals consists of of how many percentage of silver bromide and silver iodide?
Silver bromide: 98%
Silver iodide: 2%
Interaction of x-ray and light photons with these high-Z atoms ultimately results in the formation of a latent image on the radiograph
Silver halide crystals
Invisible image formed after exposure to radiation
Latent image