Radiographic Equipment and Maintenance Flashcards

Which component of the x-ray tube is responsible for producing electrons through thermionic emission?

Answer: Filament (cathode)

The filament at the cathode is heated by a low-voltage current, causing thermionic emission — the release of electrons from the wire.

The primary purpose of the rotating anode in an x-ray tube is to:

Answer: Distribute heat over a larger target area to prevent damage

The rotating anode distributes the heat generated during x-ray production over a larger area (the focal track), preventing localized overheating and extending tube life.

The line-focus principle in x-ray tube design allows for:

Answer: A large actual focal spot that produces a small effective focal spot for improved image sharpness

The line-focus principle uses an angled anode target so that a large actual focal spot (better heat loading) projects as a small effective focal spot (better image sharpness).

Which of the following is a quality control test that evaluates the accuracy of the x-ray beam's alignment with the light field?

Answer: Beam-light field congruence test

The beam-light field congruence test verifies that the visible light field from the collimator accurately represents the x-ray field, ensuring proper collimation.

The heel effect in radiography refers to:

Answer: Reduced x-ray intensity on the anode side of the beam compared to the cathode side

The heel effect occurs because x-rays produced at depth within the anode must travel through more anode material when exiting toward the anode side, reducing their intensity on that side.

During a quality control assessment, kVp accuracy is typically evaluated using a:

Answer: Digital kVp meter (non-invasive kVp meter)

Non-invasive digital kVp meters measure the actual peak kilovoltage output of the x-ray unit and are used to verify kVp accuracy during quality control.