Abstract

The recent Spacelab 3 mission utilized a holographic system to study triglycine sulfate (TGS) crystals produced by low-temperature solution growth. The experiment is of twofold interest to the optics community, since not only did it use an elaborate holographic system, but it gave insight into the growth properties of TGS, a very interesting optical material. A holographic system was chosen to allow optical techniques which were difficult to apply in orbit to be used after the flight by analyzing the holographic reconstructed images. The holograms show 3-D images of the growing crystal and interferometric data on solution temperature and concentration profiles. They are being analyzed by schlieren, shadowgraph, interferometric, and microscopic techniques. Preliminary results are presented. TGS is of interest as an optical material because of its use as a room-temperature infrared thermal detector, with important applications in astronomy, earth observation, environmental analysis, and the military. However, actual performance falls short of its potential, apparently due to common crystallographic defects which may be caused by gravity-driven convection. Convection was eliminated during the flight. It is hoped that the experimenter can understand, control, and model those aspects of the growth process which lead to high-quality single crystals.

© 1985 Optical Society of America