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Determination of the direction of the crystal optical axis of ground uniaxial precious stones by means of polarized‐light microscope photometry
Author(s) -
Boguth W.
Publication year - 1987
Publication title -
journal of microscopy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.569
H-Index - 111
eISSN - 1365-2818
pISSN - 0022-2720
DOI - 10.1111/j.1365-2818.1987.tb01315.x
Subject(s) - uniaxial crystal , microscope , optical axis , photometry (optics) , optics , rotation (mathematics) , optical microscope , displacement (psychology) , materials science , photoelectric effect , geology , physics , computer science , artificial intelligence , computer vision , scanning electron microscope , lens (geology) , psychotherapist , psychology , stars
SUMMARY The direction of the crystal optical axis of a uniaxial microscopic object is determined on the basis of the known correlation between this direction, the displacement of isogyres of the conoscopic figure, and the rotation of the microscope stage. It is shown that the use of photoelectric equipment for indicating the displacement, a stepping motor controlled by a microprocessor for rotating the stage, and a desk calculator for processing the photometric data provides a more convenient and accurate determination than classicial procedures, involving visual inspection and manual operation. The method is particularly suitable for uniaxial crystals of the size and shape of precious stones.