Precise Visualization of the Non-Steady State Concentration Field around a Growing Crystal in Solution

Etsuro Yokoyama¹, Koichi Okada² and Katsuo Tsukamoto³

¹Department of Perceptual Science and Design Engineering, Faculty of Engineering, Yamaguchi University, Tokiwadai 2557, Ube 755-8611 Japan
²Graduate School of Science and Engineering, Yamaguchi University, Tokiwadai 2557, Ube 755-8611, Japan
³Institute of Mineralogy, Petrology and Economic Geology, Faculty of Science, Tohoku University, Aramaki Aoba, Sendai 980-8578, Japan

(Received December 7, 1998; Accepted February 2, 1999)

Keywords: Crystal Growth, Interferogram, Concentration, Fringe Analysis

Abstract. To investigate the non-steady state concentration field around a crystal growing from solution, we present a method to visualize the precise equal-concentration lines from sequence microscopic interferograms. Our method is a technique of automated fringe analysis based on computer image processing, in which the interference pattern by means of a conventional two-beam interferometer is transformed into the qusi-phase-shift interferogram using thinning process of fringes and linear interpolation of phase between lines. Furthermore, after phase unwrapping we remove the phase due to the tilt of reference mirror of an interferometer from the full phase. We show the relevant counter map of phases about the concentration distribution develops during the growth of crystal.