X-Ray Tube Basics
The area of the target from which x-rays are emitted.
What is the focal spot?
The component that holds the filament and focuses electrons toward the anode.
What is the focusing cup?
The material most commonly used for the x-ray tube target.
What is tungsten?
Smaller focal spots produce this improvement in image quality.
What is higher spatial resolution?
What is higher spatial resolution
The side of the beam that has greater x-ray intensity.
What is the cathode side
The center of the x-ray beam.
What is the central ray?
The negatively charged cloud of electrons surrounding the filament.
What is the space charge?
Tungsten has this atomic number, which helps produce efficient x-rays.
What is 74
The trade-off that occurs when focal spot size decreases.
What is increased heat concentration on the target?
The side of the beam that has lower x-ray intensity.
What is the anode side
The radiation used to create the radiographic image.
What is the useful beam?
The phenomenon where electrons repel each other and limit further electron emission.
What is the space charge effect?
One property of tungsten that helps it withstand extreme heat (3400°C).
What is a high melting point?
The principle that allows a large actual focal spot but a small effective focal spot.
What is the line-focus principle
The cause of the heel effect.
What is absorption of x-rays in the anode heel
The enclosure that provides support and reduces radiation leakage.
What is the tube housing?
The process where heating the filament releases electrons.
What is thermionic emission?
The type of anode that spreads heat over a larger surface area by spinning.
What is a rotating anode
Decreasing this will decrease the effective focal spot size.
What is the target angle
Body part positioning rule for the heel effect.
What is place thicker anatomy toward the cathode?
The material typically used to make the glass envelope of the x-ray tube.
What is Pyrex glass (or borosilicate glass)?
The tube current is controlled by adjusting this current.
What is filament current?
The motor components responsible for spinning the rotating anode.
What are the rotor and stator
Small body parts typically use this focal spot size.
What is the small focal spot
One way the heel effect becomes less noticeable.
What is increasing SID