Analysis of 3He Crystal Images Using a Computer-Generated Wire-Frame

Facetted crystals of bcc 3 He have been observed with optical techniques in magnetic fields up to 9 T. Two-dimensional projections of the 3D crystals are obtained with a CCD camera. To analyze the growth rate of the various facets an interactive computer program is developed, which allows the user to analyze pictures made of crystals showing facets that have the 110-, 100- or 112-orientation. The working principles of this program are described and a picture taken from a 3 He single crystal is analyzed as an example.