Full‐field neutron microscopy based on refractive optics

Placing a compound refractive lens (CRL) as an objective in a neutron beam generates new possibilities for 2D and 3D nondestructive mapping of the structure, strain and magnetic domains within extended objects. A condenser setup is introduced that allows correction for the lateral chromatic aberration. More generally, for full‐field microscopy the loss in performance caused by the chromatic aberration can be more than offset by introducing arrays of CRLs and exploiting the fact that the field of view can be much larger than the physical aperture of the CRL. Comments are made on the manufacture of such devices. The potential use is illustrated by comparisons between state‐of‐the‐art instrumentation and suggested approaches for bright‐field microscopy, small‐angle neutron scattering microscopy, grain mapping and mapping of stresses. Options are discussed for depth‐resolved imaging inspired by confocal light microscopy. Finally, experimental demonstrations are given of some of the basic properties of neutron full‐field imaging for a single CRL. A theoretical description is provided of full‐field neutron microscopy based on refractive optics. The potential use is illustrated by comparison with the state of the art within bright‐field microscopy, small‐angle neutron scattering microscopy, mapping of grains and stresses, and confocal microscopy.