What is an X-ray Tube?

The X-ray tube is the radiation source of a CT system, based on accelerated electrons. Its hardware characteristics determine what information quality is later available in the volume dataset.

Scientific background

Technically relevant are tube voltage, current, focal spot and spectral filtration. Throughout the complete measurement chain these factors influence signal quality, artifact susceptibility and metrological stability.

Relevant key metrics

Stability of signal formation across time and load states.
Contribution to effective resolution and contrast level.
Robustness against drift, defective pixels and thermal influences.

Standards and thresholds

Standards: ISO 15708-2:2025 (CT equipment and samples) and ISO 17636-2:2022 (corr. 2023-02) for digital radiographic requirements.
Typical thresholds (in practice): Effective focal spot size per inspection task (e.g. micro-focus for high-resolution defect detection); stable tube parameters without impermissible drift.
Validity: Operating limits follow manufacturer release, maintenance schedule and regulatory requirements.

Application in industrial practice

Adaptation of the measurement chain to dense or multi-material parts.
Reliable defect detection on small structures.
Reproducible series inspection with consistent quality metrics.

Sources and reference date

ISO 15708-2:2025.
ISO 17636-2:2022 (corr. 2023-02).
Reference date: February 2026.