Patent ID: 8260242

Claim:
A bandpass filter comprising: a laminated body comprising a plurality of dielectric layers and interlayers including a first interlayer, a second interlayer and a third interlayer located on a opposite side of the second interlayer of the laminated body from the first interlayer; a plurality of strip-shaped resonant electrodes in the first inter-layer, comprising: an input resonant electrode; an output resonant electrode; and one or an uneven number of resonant electrodes, wherein the plurality of resonant electrodes is arranged in parallel and is configured to electromagnetically couple to each other; and each comprises a ground end connected to a ground potential and an open end, wherein the open ends and the ground ends are alternately arranged; a strip-shaped input coupling electrode in the second interlayer, comprising: a first portion facing at least a half portion of the input resonant electrode in a longitudinal direction thereof; and a signal input point located closer to the open end of the input resonant electrode than a center of the first facing portion in the longitudinal direction; a strip-shaped output coupling electrode in the second interlayer, comprising: a second portion facing at least a half portion of the output resonant electrode in a longitudinal direction thereof; a signal output point located closer to the open end of the output resonant electrode than a center of the second facing portion in the longitudinal direction; and a coupling conductor in the third interlayer, comprising: an input coupling portion facing both the input coupling electrode and the input resonant electrode, and configured to electromagnetically couple to the input coupling electrode and the input resonant electrode; an output coupling portion facing both the output coupling electrode and the output resonant electrode, and configured to electromagnetically couple to the output coupling electrode and the input resonant electrode; and a connecting portion electrically coupling the input coupling portion and the output coupling portion.