In plain language
In laboratory reference X-ray beams, a CERN-derived pixel detector measured current and newly proposed staff dose quantities within 5% up to 70 kVp and about 20% off at 120 kVp. It has not yet been tested in clinical fluoroscopy rooms.
At a glance
- Type of study
- Original research, Dosimetry measurement study
- Size
- n = 8 beam qualities
- Where
- Switzerland
- Summary based on
- the full text
What it found
The Timepix4 hybrid pixel detector measured both current (H*(10)) and newly proposed International Commission on Radiation Units and Measurements (ICRU) 95 (H*) ambient dose quantities within 5% of a reference ionisation chamber up to 70 kVp.
Key figures: within 5% up to 70 kVp
Accuracy fell at higher tube voltages, with deviations of about 20% at 120 kVp, attributed to fluorescence from bonding materials and low silicon sensor efficiency.
Key figures: approximately 20% at 120 kVp
Repeat measurements were highly stable for a given beam quality.
Key figures: standard deviation not higher than 0.5%
All measured values fell within IEC 60846-1 relative response limits, so the authors consider the detector already compliant with existing standards.
The authors note that conventional radiation protection detectors overestimate staff exposure by about a factor of two at diagnostic X-ray energies, motivating spectral dosimetry.
Key figures: approximately a factor of two
Limits to keep in mind
Tested only in a calibration laboratory with continuous, unscattered standard IEC 61267 RQR/RQA beams at a non-reference 2.5 m distance, not in pulsed scattered fields in clinical rooms or worn by staff. Accuracy degrades above 70 kVp and the silicon sensor is unsuitable above 150 keV.
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How this summary was made
ORSIF prepared this summary with AI assistance from the full text of the paper. A program then checked that the passage supporting each finding appears word for word in that source. A person has not yet reviewed each summary, so read the original before relying on a number. ORSIF summarizes research and does not endorse any product or company. Report a problem with this summary.
Prepared November 3, 2026.