Beam Stop Phantom

For the determination of the scatter distribution of X-ray cone-beam CT and to develop scatter correction techniques

Convenient performance of scatter measurements in radiological setups
Array of lead cylinders embedded in a PMMA plate

The Beam Stop Phantom consists of a regular array of lead cylinders embedded in a PMMA plate. Lead blockers offer an attenuation sufficient to prevent primary radiation reaching the detector. The Beam Stop Phantom is a convenient tool to experimentally determine the X-ray scatter-to-primary-ratio for a given measurement setup for analog and digital radiography.

The Beam Stop array is placed between the object and the X-ray source or between the object and detector.

A measurement of the signal level behind each blocker gives the scatter intensity, whereas a measurement without the phantom represents the total intensity (scatter and primary signal). Dividing both values results in the scatter fraction.

Beam Stop Phantom, QRM-10115