PARTICLE SIZE MEASURING DEVICE OF CRYSTAL, PARTICLE SIZE MEASURING METHOD OF CRYSTAL, PROGRAM AND COMPUTER READABLE MEMORY MEDIUM

摘要

PROBLEM TO BE SOLVED: To measure the particle size of the crystal of a plate to be measured even in the case the thickness of the plate to be measured is extremely thin.;SOLUTION: The waveform of an ultrasonic wave in each of the frequencies of a predetermined frequency region containing the resonance frequency propagated in the thickness direction of the plate 101 to be measured is detected by a waveform detection means 30 and the energy value of the ultrasonic wave in each of the frequencies of the predetermined frequency region is calculated on the basis of the detected waveform of the ultrasonic wave by an energy value calculation means 40. The maximum energy value being the energy value of the ultrasonic wave in resonance frequency is detected from the energy values calculated by the energy value calculation means 40, and the ratio of this maximum energy value to an energy value other than the maximum energy value is calculated by a ratio calculation means 60 and, in a crystal particle size calculation means 80, the particle size of the crystal in the plate 101 to be measured is calculated on the basis of the ratio of the energy values calculated in a ratio calculation means 60.;COPYRIGHT: (C)2007,JPO&INPIT