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:
Jun. 30, 1998
Filed:
Jul. 29, 1997
Mitsuhiro Tanaka, Chita-Gun, JP;
Masao Takeuchi, Natori, JP;
Kazuhiko Yamanouchi, Sendai, JP;
Hiroyuki Odagawa, Sendai, JP;
NGK Insulators, Ltd., , JP;
Abstract
A surface acoustic wave device including a piezoelectric substrate having NSPUDT behavior and a directionality reversed electrode structure including positive electrode, negative electrode and floating electrode. Positive and negative electrode fingers each having a width of .lambda./8 are arranged interdigitally at a pitch of .lambda. and floating electrode fingers having a width of 3 .lambda./8 are arranged between successive positive and negative fingers with an edge distance of .lambda./8. A directivity due to NSPUDT behavior of the substrate can be reversed. Positive and negative electrode fingers are arranged interdigitally at a pitch of .lambda. and between successive positive and negative electrode fingers are arranged floating electrode fingers having a reflecting coefficient different from that of the positive and negative electrodes.