Dual energy methods

Dual energy techniques are well-established in medical applications. Applying latest developments of Fraunhofer EZRT entirely new fields of application or the enhancement of existing applications become possible. Thus, in contrast to conventional X-ray techniques, quantitative information about e.g. density, mass percentages or other characteristics becomes available.

Dual energy techniques are employing the fact that the attenuation coefficient of a material is different for individual materials. This means that from energy resolving („spectral“) measurements the input data for a quantitative determination of material properties can be obtained.

In practice, this energy resolving measurement is usually conducted by acquiring two X-ray images using different X-ray spectra. Alternatively, a special dual energy detector can be applied. Due to its setup with two different energy channels only one measurement has to be conducted.

System solution 2XCT

In order to comply with the requirements of dual energy measurements Fraunhofer EZRT’s 2XCT device has several special properties. It is equipped with a revolver filter changer allowing the easy changing of pre-filters for dual energy measurements, thus enabling a manipulation of spectral parameters without manual intervention. The filter changer has six different filter chambers which can be individually loaded with different filter materials. Additionally, the device is equipped with a collimator unit. The collimator can be applied for the reduction of scattered radiation, thus enhancing analysis quality. In principle, however, Fraunhofer dual energy techniques can be ported and applied to conventional X-ray systems without constructional changes.

  • Safety and security technology: Testing luggage for dangerous substances or goods
  • Recycling: Separating materials in order to recover raw materials
  • Mining: Improved detection of diamonds in surrounding rock

X-ray tubes Closed system
Tube voltage

Max. 225 kV

Tube current Max. 3.5 mA or 8 mA
0.4 or 1.0 mm
switchable focal point
(EN 12543)
Detector Surface detector
(GOS scintillator on
amorphic silicon)
16-bit digitization depth
1024 x 1024 pixels
200 μm pixel spacing
Sample weight Max. 15 kg
Sample size Max. Ø 130 mm

Advantages and customer value

  • Mapping and quantification of distribution of various materials within the test object
  • Usable both for radiographic imaging (2D) as well as x-ray computer tomography (3D)
  • Higher contrast on materials with similar or very different weakening co-efficient
  • Correction of beam-hardening artifacts possible.