Polychromatic neutron phase-contrast imaging of weakly absorbing samples enabled by phase retrieval

Area of Science:

• Materials Science
• Medical Imaging
• Physics

Background:

• Neutron imaging offers unique material contrast but often suffers from low signal-to-noise ratios.
• Phase-contrast imaging enhances sensitivity for materials with low absorption.
• Polychromatic neutron beams are advantageous for time-resolved studies but pose challenges for phase retrieval.

Purpose of the Study:

• To demonstrate a phase-retrieval technique for propagation-based phase-contrast neutron imaging using a polychromatic beam.
• To improve imaging of samples with low absorption contrast.
• To enhance signal-to-noise ratios for applications like time-resolved measurements.

Main Methods:

• Utilized a phase-retrieval algorithm applied to propagation-based phase-contrast neutron imaging data.
• Employed a polychromatic neutron beam for imaging.
• Tested the technique on a metal sample (near phase-pure object) and a bone sample with deuterated water (D2O) filled canals.

Main Results:

• Significantly improved signal-to-noise ratios were achieved for both metal and bone samples.
• Phase retrieval enabled clear separation of bone and D2O in the bone sample.
• Demonstrated the potential for in situ flow experiments using deuteration contrast.

Conclusions:

• Phase-retrieval is effective for polychromatic neutron imaging, enhancing contrast and signal-to-noise.
• This technique facilitates detailed analysis of low-contrast materials and biological samples.
• Neutron imaging with phase retrieval, particularly using deuteration contrast, is a valuable complementary method to X-ray imaging for bone research.