Film Flashcards
Provides rigid structure on film imaging
Base
“active” layer on film; made with gelatin and silver halide crystals
Emulsion
Lowers patient dose, controls screen speed and uses luminescence/fluorescence
Intensifying screen
Intensifying screens have ___ layers
4; protective coating, phosphor, reflective layer, base
The emission of light when stimulated by radiation
Luminescence
The ability of phosphors to only emit light when exposed to x-rays
Fluorescence
At what stage does the process of removing unexposed and undeveloped silver halide from the film emulsion occur?
Fixing
The front or tube side of radiographic cassettes should be made of a material that:
Absorbs very little of the x-ray beam
The greater the film speed, the ______ sensitive it is.
more
The greater the film speed, the number of silver halide crystals ______
increases
The intensifying screens convert the exit radiation intensities into:
visible light
The radiation- and light-sensitive material used in the emulsion of radiographic film is called?
Silver halide crystals
What is the correct sequence of film processing?
developing, fixing, washing, drying
What is the outermost, durable protection layer of radiographic film called?
Supercoat
What is the purpose of the intensifying screen?
To reduce the amount of exposure to the patient
What is the term specifically used to emit visible light during x-ray exposure with little or no afterglow?
Fluorescence
When a film has emulsion coated on both sides of the base versus one side of the base, the film is referred to as:
Double-emulsion film
Which layer of the intensifying screen is closest to the film and protects the phosphor?
Protective layer
Which layer of the radiographic film contains crystals suspended in gelatin that serve as the latent imaging centers?
Emulsion
Which of the following is a major limitation in film-screen imaging?
Limited dynamic range
According to the Gurney-Mott theory, exposure of the silver bromide crystals in the film emulsion by light or x-ray photons creates the latent image and initiates the conversion process. What completes the conversion process and transforms the image into a permanent visible image?
Chemical processing
In film, the most important layer is the:
Emulsion layer
Latent image formation occurs during film ____
Exposure
What is the first step in film processing?
Developer
What is the latent image center for radiographic film?
Sensitivity speck
What describes a film’s sensitivity to light?
Speed
What chemical agent is responsible for clearing the unexposed silver halide crystals during film processing?
Ammonium thiosulfate
Why is silver recovery necessary during film processing?
A. It is a natural resource.
B. It is toxic to the environment.
C. It has monetary value.
D. All of the above
D
What reducing agent acts slowly to produce the higher densities on a film radiograph?
Hydroquinone
Which automatic processing system primarily maintains the chemical activity level?
Replenishment
What term is defined as a measure of the amount of light transmitted through the film?
OD
What is the diagnostic range of optical densities?
0.5 to 2.0
Changes in radiation exposure have the greatest effect on optical densities in which sensitometric region?
straight-line
When the exposure technique used produces densities outside the straight-line portion of a sensitometric curve, how was contrast affected?
Decreased
What do dry imagers use to process the latent image on the film?
Heat
