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:
Feb. 16, 1988
Filed:
Sep. 02, 1986
Sadao Igarashi, Soma, JP;
Alps Electric, Ltd., , JP;
Abstract
A waveguide filter is provided which comprises a plurality of waveguide resonators arranged in series in the longitudinal direction of the filter with each contacting tightly with adjacent ones, each of the waveguide resonators being composed of a rectangular dielectric having a length and a permittivity complying with the center frequency of a bandpass filter, on the periphery of which a metal film is provided except on the portions of induction windows of its two sides mutually opposed in the longitudinal direction. According to another feature, the metal film of each waveguide resonator is provided while keeping free additionally a no-electrode portion of the bottom side of the reactor, a supporting base on which the waveguide resonators are secured has concave portions formed therein so as to confront the respective no-electrode portions, and adjusting members made of dielectric material are provided slidably and retractably into the respective concave portions so as to vary the respective opening areas of the no-electrode portions.