| 摘要 |
PURPOSE:To improve measuring function significantly by a method wherein the ratio of a period of an interference wave and a period of a reflective sonic wave from a specimen which is generated when the distance changes is detected and an average propagation speed of a surface elastic wave is obtained. CONSTITUTION:The intensity data (an output of an analog/digital converter 655) of a reflective signal from a specimen 610 and the distance data (an output of an up-and-down counter 635) are stored in a memory of a microcomputer 670. A V(Z) curve which is obtained based upon the pairs of above ''intensity data'' and ''distance data'' is displayed and recorded by a CRT display, protter or the like. lambdaL/2 and the magnitude of a period DELTAZC reflecting material quantities are obtained by the microcomputer from the V(Z) curve modulated by interference. VR is obtained by processing according to a formula using the ratio of the magnitude of DELTAZN thus obtained and the magnitude of DELTAZc. IN the formula, VR means an average propagation speed of a surface elastic wave, lambdaL means a sonic wavelength of a fluid filling the space between a lens and the specimen, VL means a propagation speed of sonid wave and DELTAZN means a period of the V(Z) curve. |
