US Patent No. 9,198,279

NOISE FILTER AND TRANSMISSION APPARATUS


Patent No. 9,198,279
Issue Date November 24, 2015
Title Noise Filter And Transmission Apparatus
Inventorship Seiji Hayashi, Yokohama (JP)
Assignee Canon Kabushiki Kaisha, Tokyo (JP)

Claim of US Patent No. 9,198,279

1. A printed wiring board comprising:
an insulator layer;
a first wiring layer formed on one surface of the insulator layer, wherein the first wiring layer includes a pair of signal
wirings and at least three guard wirings provided between the pair of signal wirings, and wherein the least three guard wirings
are spaced apart from one another along the pair of signal wirings; and

a second wiring layer formed on another surface of the insulator layer and provided with a plane conductor,
wherein one via hole and all of the at least three guard wirings are configured to electrically connect the at least three
guard wirings to the plane conductor via the one via hole so that all of the at least three guard wirings have substantially
the same potential.