A ring coded-aperture microscope for high-resolution imaging of high-energy x rays

We use annular apertures to produce coded images of inertial-confinement fusion targets. The images are formed with 4--9-keV x rays; they are unfolded to obtain high-quality estimates of the source spatial distribution. Excellent time-integrated images have been obtained using x-ray film as a detector, and we are working to obtain time-resolved images using a gated microchannel-plate x-ray detector. Preliminary resolution-grid experiments show that the spatial resolution is ≤5 μm, and further experiments are planned to confirm a predicted resolution of ≤3 μm. We discuss the apertures, x-ray detectors, and image-processing software that forms this novel x-ray microscope