X-ray imaging

Synopsis

The last few years have seen major developments in synchrotron-radiation-based X-ray imaging techniques (absorption, phase contrast, diffraction, fluorescence). These developments are based on the coupling of beam features with new detectors and computers. As a result, users have many new options, including three-dimensional imaging, higher spatial resolution, the possibility to exploit the coherence of the beam, and setups permitting in situ and real-time observation, as well as combinations of these options. The X-ray Imaging Group support not only traditional physical, medical, materials science and engineering subjects, but also new areas for X-ray imaging, such as environmental, archaeological, palaeontological and biological studies. The introduction to the group's chapter in the annual ESRF Highlights gives an overview of some recent accomplishments.

ID17 and ID19 are “long” beamlines (about 150 m) to take advantage of a wide, homogeneous and coherent beam in the 7-250 keV range. These features are important for the palaeontology facility, which is presently being established.

ID17 covers various aspects of synchrotron-based biomedical research. Most of the scientific applications take advantage of the coupling of diagnostic and functional imaging with radiation therapy. This work rests on a strong collaboration with local and European hospital teams, and the efficient use of the ESRF Biomedical Facility.

ID19 is mainly devoted to 3D imaging (microtomography, laminography), with an intensive use of phase contrast. These techniques are applied to a wide variety of topics, with a present emphasis on palaeontology. This beamline is moving towards higher spatial and temporal resolutions, with spatial resolution now in the 0.5-1 µm range, while a 3D acquisition can be performed within seconds. The use of a monochromatic beam allows, when required, quantitative analysis.

The microscopy and microanalysis beamlines ID21 (“low energy,” 2-9 keV) and ID22 (“high energy,” 7-60 keV) are complementary. Various techniques including tomography, fluorescence, absorption spectroscopy, and diffraction, can be combined for two or three-dimensional microanalysis on the same sample. On ID21 an infrared microscopy end-station extends, when coupled to the X-rays, the range of microanalysis techniques.

ID22 will evolve within the frame of the upgrade programme of the ESRF towards the long (185 m), two-branch Nano Imaging and Nano-Analysis (NINA) beamline. Initial development will performed through the pilot project ID22NI. The NINA beamline will be located on port ID16 and is scheduled to open for users in January 2014. It will provide complementary techniques at the nano-scale for the study of both biological and materials science samples. 

Techniques

The X-ray imaging beamlines offer scanning and full field methods in two and three dimensions with different contrast conditions combined to exploit the brilliance and coherence properties of the ESRF:

• Full field techniques
• Computed tomography (CT)
• Radiography (absorption and/or phase sensitive contrast)
• Diffraction imaging
• Scanning techniques
  
• Complementary imaging modes, e.g., fluorescence, scattering or absorption spectroscopy
• Irradiation for medical therapy
  

Spatial resolution resolutions range from a few hundred micrometres to the nano regime; energies range from a few keV up to several 100 keV.

Industrial applications

The ESRF’s mission includes interacting with and supporting European industry. Synchrotron X-rays permit analysis of industrial products under real conditions of manufacture and use, often in real time.

For example, the X-ray Imaging Group's tomography capabilities are attractive for three-dimensional imaging of commercial materials. For example, the combination of beam intensity, fast data acquisition, and low-temperature environment made ID19 the right place to study exactly how ice cream degrades when the temperature rises. Also, with fast 3D microtomography it is now possible to watch in 3D as alloys solidfy.

The individuals listed above and the staff of the Industrial and Commercial Unit are available to help industrial researchers identify appropriate resources at the ESRF.

Related beamlines

• ID13 Microfocus (microdiffraction)
• ID15 High energy (fast microtomography at energies > 60 keV)
• ID24 Dispersive EXAFS (detection of trace elements on semiconductors)
• (ID18F Microanalysis end station is now closed, please use ID22 instead)