ACOUSTIC MATCHING LAYER AND FLUID FLOW MEASURING INSTRUMENT

摘要

PROBLEM TO BE SOLVED: To solve the problem that acoustic impedance is small but a strength is weak and it is hard to handle an acoustic matching layer of a porous body comprised of a dry gel of an inorganic oxide. SOLUTION: An acoustic matching layer 1 uses a porous body resulting from sintering the dry gel of the inorganic oxide. As the dry gel of the inorganic oxide, there is phosphoric acid glass, for example. The porous body obtained by using the method has a void of a nano size, acoustic impedance from 2×105kg/m2s to 10×105kg/m2s can be obtained and the acoustic matching layer can be made strong. COPYRIGHT: (C)2005,JPO&NCIPI