phantom

A physical test object with known properties, used to verify scanner calibration. Water phantom (CT), body phantom (MRI NEMA), paraffin (mammo MQSA).

Why it matters to buyers: Phantom QC is required by ACR accreditation and performed daily (CT), weekly, or monthly per modality.

Why it matters to engineers: Phantom failures are the #1 trigger for service calls at daily QC time.