ACOUSTIC MATCHING MEMBER, ULTRASONIC TRANSDUCER, ULTRASONIC FLOWMETER, AND MANUFACTURING METHODS FOR THEM

摘要

PROBLEM TO BE SOLVED: To provide an acoustic matching member in which releasing between layers hardly occurs and which hardly fails and to provide an ultrasonic transducer, an ultrasonic flowmeter and methods for manufacturing them. SOLUTION: The acoustic matching member (100) to be assembled in the ultrasonic transducer for transmitting or receiving an ultrasonic wave includes at least two layers of a first layer (11) and a second layer (12) having different acoustic impedances. The first layer (11) is a composite material of a porous material (1) and a filling material (2) carried in air gaps of the material (1). The second layer (12) is the filling material (2) or the porous material (1). The first layer (11) and the second layer (12) are sequentially laminated in this order. A piezoelectric material is disposed at the first layer side (11) of the acoustic matching member (100) to form the ultrasonic transducer and the ultrasonic flowmeter. There is no independent intermediate layer between the layers of the matching member (110). COPYRIGHT: (C)2004,JPO