Z Backscatter technology was pioneered by AS&E.

It is the proven approach for the discrimination of organic materials such as explosives, drugs, cigarettes, and people, especially when hidden within a complex environment.

  • The photo-like images are easy-to-interpret, revealing both the presence and exact position of organic components of the scanned object.
  • It is the most effective X-ray technology for the detection of organic materials.
Z Backscatter Technology

How Do X-rays work?

When X-rays interact with matter, they do one of three things:

  • Pass through the object
  • Get absorbed by the object
  • Scatter from the object

Objects with higher density absorb more X-rays than objects with lesser density. Much organic material is low-density and X-rays scatter when they interact with organic objects.

Traditional transmission X-ray images like medical X-rays result when X-rays pass through an object to a detector located on the far side of the object. The resulting image is bright where most of the X-rays pass through the object and dark where most X-rays are absorbed.

Z Backscatter technology captures the data from the X-rays that are scattered away from the object, back towards a near-sided detector. This primary scattering effect is known as “Compton Scattering.” The Z Backscatter image is bright white where X-rays scatter the strongest, indicating organic matter, such as explosive material and drugs. Even inorganic objects, such as metals, are given shape and form in Z Backscatter images.

The difference with Z Backscatter

We create photo-like Z Backscatter images showing organic materials by directing a sweeping beam of X-rays at the object under examination, and then measuring and plotting the intensity of scattered X-rays as a function of the beam position. This is made possible by patented “Flying Spot” technology. Flying Spot technology allows the position of the X-ray beam to be defined at every instant. So any Z Backscatter signal received is easily correlated with the precise region of the object undergoing inspection.

Z Backscatter's photo-like images are easy-to-interpret, revealing both the presence and exact position of organic components of the inspected object. This significantly enhances the ability of operators to quickly understand and interpret scan results.

Z Backscatter image of vehicle

Z Backscatter image of a vehicle highlights concealed drugs in the rear panel.

Combination of technologies

Because of the complementary nature of transmission imaging, which reveals metallic threats, and Z Backscatter imaging, which highlights organic threats, many of our products offer a combination of these technologies. With both Z Backscatter and transmission imaging, inspectors get more richly detailed information about the contents of the object under inspection for greater detection capabilities.

Combinational imaging

Combinational imaging of a vehicle with Z Backscatter X-ray that highlights concealed organic threats and Transmission X-ray that reveals hidden weapons.