The French laser megajoule project
addresses fusion by inertial confinement.
A problem is characterizing the
inner surface of the approximately
spherical target by optical shadowgraphy,
which produces caustics of
systems of optical rays and contains
a great deal of 3D information. (top)
Laser megajoule target. (bottom)
Building with 10 m diameter shooting
sphere. For details, see the paper by
Choux et al., pp.