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:
Nov. 21, 1978
Filed:
Sep. 15, 1976
Yahei Koyamada, Tokorozawa, JP;
Fujio Ishihara, Tokyo, JP;
Abstract
An impedance element is disclosed which is formed with an electro-elastic surface wave transducing device composed of a substrate for the propagation of an elastic surface wave and an electro-elastic surface wave transducer disposed on the substrate for converting an electrical signal into an elastic surface wave or vice versa. The impedance element has a frequency-impedance characteristic that it exhibits a sufficiently high impedance in a predetermined frequency band but a sufficiently low impedance in the other frequency bands. Further, a band-rejection filter is disclosed which includes the abovesaid impedance element and has a band-rejection filter characteristic dependent upon the frequency-impedance characteristic of the impedance element.