Podcast Beta
Questions and Answers
Photography is a record made by means of ______ light
visible
Radiography is a record made by ______ radiation.
X-ray
The formation of a visible image is a ______ way step process.
two
The image chain includes a ______ image that is invisible on the radiographic film until processing occurs.
Signup and view all the answers
Primary radiation is the ______ beam after it exits the X-ray tube and before it interacts with the patient's body.
Signup and view all the answers
Remnant radiation is the ______ of radiation after it passes through the patient's body.
Signup and view all the answers
Materials that allow X-ray photons to pass through easily are called ______.
Signup and view all the answers
Bone has a ______ absorption of X-rays (white).
Signup and view all the answers
The penetrating power of radiation depends on the ______ number.
Signup and view all the answers
Silver halide is a chemical compound formed between silver and one of the ______.
Signup and view all the answers
Silver halides are used in ______ film and photographic paper.
Signup and view all the answers
Silver halides, except for ______ fluoride, are extremely insoluble in water.
Signup and view all the answers
A ______ compound is formed between silver and one of the halogens.
Signup and view all the answers
[Blank] materials use silver bromide.
Signup and view all the answers
Silver iodide is never used ______.
Signup and view all the answers
Certain positive materials use ______ chloride.
Signup and view all the answers
The photosensitive layer containing silver halide is suspended in ______ (on an x-ray film).
Signup and view all the answers
Change occurs in the silver halide ______ on exposure to light
Signup and view all the answers
A photographic emulsion is a dispersion of small solid particles in a ______ medium.
Signup and view all the answers
Photographic emulsion is made by adding a solution of ______ nitrate into a warm gelatine solution
Signup and view all the answers
Silver ______ (AgBr) is produced by mixing aqueous solutions of silver ions and halide ions
Signup and view all the answers
Light sensitive materials are affected by ______ and temperature
Signup and view all the answers
The characteristics of sensitive emulsion include ______ and contrast
Signup and view all the answers
The speed of the emulsion depends on the ______ of silver halide crystal
Signup and view all the answers
A ______ image is an invisible image formed on a film as a result of exposure to radiation
Signup and view all the answers
Photographic emulsion consists of light and X-ray sensitive ______ and gelatin.
Signup and view all the answers
Silver bromide (AgBr) is a ______ crystal containing millions of pairs of ions
Signup and view all the answers
Gelatin is a ______, colorless, brittle, nearly tasteless, extracted from the collagen inside animals' skin and bones.
Signup and view all the answers
Gelatin acts as the medium for the formation of ______ halide crystals during chemical production.
Signup and view all the answers
The contrast of the emulsion depends on the ______ of size of the grains
Signup and view all the answers
Gelatin maintains the uniform distribution of ______ halide in the liquid emulsion.
Signup and view all the answers
The exposure latitude of the emulsion is affected by the ______ of grain sizes
Signup and view all the answers
In solid state, gelatin can be ______ and then allows penetration by the chemical agents.
Signup and view all the answers
Gelatin holds firmly in position the ______ silver particles.
Signup and view all the answers
Gelatin provides a ______ medium, enabling viewing of the image.
Signup and view all the answers
Gelatin is a ______ medium for the formation of silver halide crystals during chemical production.
Signup and view all the answers
Each silver bromide grain contains on the order of ______ atoms.
Signup and view all the answers
Silver bromide grains are irregularly shaped like ______ or grains of sand.
Signup and view all the answers
When solid silver bromide is formed, the silver atoms each give up one ______ electron to a bromine atom.
Signup and view all the answers
The silver atoms, lacking one negative charge, have an effective ______ charge and are known as silver ions.
Signup and view all the answers
The bromine atoms, on the other hand, have gained an ______ and have become bromine ions.
Signup and view all the answers
When a photon of light of energy greater than a certain minimum value is absorbed in a silver bromide crystal, it releases an ______ from a bromide ion.
Signup and view all the answers
The negatively charged trap can then attract an ______ silver ion because the silver ion is charged positively.
Signup and view all the answers
The whole cycle can recur several, or many, times at a single trap, each cycle involving absorption of one ______ and addition of one silver atom to the aggregate.
Signup and view all the answers
Study Notes
Radiographic Imaging
- Radiography is a record made by means of X-ray radiation, whereas photography is a record made by means of visible light
- Formation of a visible image is a two-way step process:
- Exposure of the film to light produces an invisible latent image
- Chemical process that converts the latent image into a visible image with a range of density, or shades of gray
Image Production by X-Radiation
- The image chain:
- Latent image: an invisible image on the radiographic film until processing occurs
- Radiograph: an image produced by X-ray photons on a piece of radiographic film
- Terms related to image production:
- Primary radiation: X-ray beam after it exits the X-ray tube and before it interacts with the patient's body
- Remnant radiation: remainder of radiation after it passes through the patient's body, producing the image on the radiographic film
- Secondary scatter radiation: radiation that may not reach the film but does not carry any useful information
- Attenuation: process by which primary radiation is changed or absorbed as it travels through the patient
- Radiolucent: materials that allow X-ray photons to pass through easily (e.g., air)
- Radiopaque: materials that do not allow X-ray photons to pass through easily (e.g., bone)
Tissue Absorption of X-Rays
- Different tissues in the body absorb X-rays at different extents:
- Bone: high absorption (white)
- Tissue: middle absorption (gray)
- Air: low absorption (black)
X-Ray Beam Interaction with Body
- As X-ray beam passes through the body:
- Absorbed
- Transmitted
- Scattered
- Factors affecting X-ray beam interaction:
- Penetrating power of radiation
- Atomic number
- Density
- Thickness of the material
Silver Halides
- A silver halide is a chemical compound formed between silver and one of the halogens (e.g., silver bromide, silver iodide, silver chloride, silver fluoride)
- Applications: light sensitivity, used in photographic film and radiographic film and paper
- Properties of silver halides:
- Except for silver fluoride, extremely insoluble in water
- Undergo change when exposed to visible light or X-ray radiation
Photographic Emulsions
- A photographic emulsion consists of:
- Light and X-ray sensitive crystals (silver halides) suspended in gelatin
- Coated on a transparent base of the film
- Properties of gelatin:
- Acts as the medium for formation of silver halide crystals during chemical production
- Maintains uniform distribution of silver halide
- Does not react chemically with silver halides
- Allows the film base to be coated evenly with warm liquid emulsion, which is then chilled and allowed to set and dry
- Holds firmly in position the metallic silver particles
- Provides a transparent medium, enabling viewing of the image
Making an X-Ray Film Emulsion
- Chemical process by which the X-ray film material is produced: precipitation
- Photographic emulsion is made by adding a solution of silver nitrate into a warm gelatine solution containing potassium bromide, sodium chloride, or other alkali metal halides at suitable proportions
- Silver nitrate (AgNO3) + potassium bromide --> silver bromide (AgBr) + potassium nitrate (KNO3)
Light-Sensitive Materials
- Affected by:
- Moisture and temperature
- Presence of impurities
- Exposure to certain gases
- Airborne dust
- Static electricity and mechanical stress
- Characteristics of sensitive emulsion:
- Speed: need for more or less exposure to light and X-ray radiation in comparison to inherent property of film emulsion to respond to light and X-ray radiation
- Contrast: the way in which the material reacts to a range of exposures by showing on development a number of different densities
Latent Image Formation
- Structure of crystals:
- Silver bromide is a lattice crystal containing millions of pairs of ions
- Silver bromide grains are irregularly shaped like sugar or grains of sand
- When solid silver bromide is formed, as in the preparation of a photographic emulsion, the silver atoms each give up one orbital electron to a bromine atom
- The liberated electron is free to wander about the crystal, and as it does, it may encounter a latent image site and be "trapped" there, giving the latent-image site a negative electrical charge
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
This quiz covers the basics of radiographic imaging, including principles of photography, film materials, sensitometry, film storage, intensifying screens, X-ray film cassettes, film processing, digital radiography, and image quality.
