A Novel Neutron Penumbral Imaging Technology for Inertial Confinement Fusion Implosions

Neutron Imaging System can be used to image the burn volume and cold fuel volume of imploding fusion capsules. In this work, a novel neutron imaging technology with FOV of 1 mm and spatial resolution of less than 10 um has been proposed. By employing a circular cone, the point spread function of NIS can be near uniform in wide FOV. A geometric model has been developed based on ray-tracing technology, and used to design the geometry parameters of the circular cone, including the radian and the length. The spatial resolution, FOV and the requirement of the alignment can be estimated with this model. Then the image reconstruction technology with high accuracy and precision has been investigated. The new technology has been demonstrated with the X-ray source with the diameter of about 30 μm. The spatial resolution of the new technology can reach up to about 1 um. The shape and size of the source can be reconstructed while the source is off the axis of the cone. The effect of the magnification and the X-ray energy has been discussed in this work. Moreover, the performance of neutron image measurement has investigated with the geometric model.