Fusion Science and Technology / Volume 63 / Number 2 / March 2013 / Pages 151-159
Technical Paper / Selected papers from 20th Target Fabrication Meeting, May 20-24, 2012, Santa Fe, NM, Guest Editor: Robert C. Cook
Capsule ablators are precision hollow spheres used in inertial confinement fusion targets used in high-peak-power laser systems such as the National Ignition Facility. These capsules have high surface-quality requirements, and hence a full surface microscopic mapping system has been developed to characterize them. The capsule-fill-tube-assembly mapping system combines a confocal surface-profiling microscope with a nine-axis, high-precision stage system to provide quantitative three-dimensional data over the entire surface of each capsule prior to assembly into the final target. The system measures the individual volumes of features on the capsule surface that are 7.5 m3 and larger with an accuracy of ±10%. The positional accuracy is better than 0.25 deg (1), or [approximately]5 m linearly. The data acquisition and image processing are all highly automated in order to keep pace with throughput demands. The system consists of four primary subsystems: the positioning system, the confocal microscope, the automated acquisition code, and the image processing and data management software.