The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 29, 1996
Filed:
Jun. 06, 1995
Yoshihiko Ishida, Nagoya, JP;
Makoto Tani, Inazawa, JP;
NGK Insulators, Ltd., , JP;
Abstract
An apparatus for transmitting and receiving ultrasonic waves has a transmitter for sending a pair of ultrasonic waves to a sample. The pair of ultrasonic waves have substantially symmetric waveforms with respect to zero sound pressure. One of the ultrasonic wave is separated from the other ultrasonic wave. An acoustoelectric, ultrasonic transducer receives the pair of ultrasonic waves affected by the sample. The acoustoelectric, ultrasonic transducer converts the pair of ultrasonic waves into a pair of electric signals accompanied by phonon-charge carrier interaction. Each of the electric signals includes an acoustoelectric signal insensitive to phase and a piezoelectric signal sensitive to phase. A processing device processes the pair of electric signals so as to remove the piezoelectric signal and obtain the acoustoelectric signal. The initial ultrasonic waves have opposite phase so that superimposition of the pair of electric signals by the processing device offsets the piezoelectric signals, thereby obtaining the acoustoelectric signals.