Wave-front shearing interferometer for cryogenic laser-fusion targets

The operating principles of a wave-front shearing interferometer designed by Murty are described. The interferometer has simple, independent adjustment for both phase and shear and is stable mechanically. It has been used to assess the quality of cryogenic laser-fusion targets immediately prior to their irradiation by a high-power laser. It has also been used to study the changes in cryogenic targets caused by energy emitted by the high-power laser prior to the main pulse.