PROBLEM TO BE SOLVED: To achieve both of the proper flexibility and excellent transmission characteristic in a wave guide of transmitting an electric wave at the frequency equal to or greater than the millimeter wave.SOLUTION: A wave guide includes: a linear dielectric body which has the uniform dielectric constant in the longitudinal direction and has the same-shaped cross section in the longitudinal direction and a metal layer 53 which is disposed at a position of covering the outer periphery of the dielectric body and formed into the cylindrical shape having the flexibility. The dielectric body includes: a first dielectric body 51 which is located on the inner side at the cross section vertical to the longitudinal direction and a second dielectric body 52 which is located on the outer side with respect to the first dielectric body 51 at the cross section vertical to the longitudinal direction and has the lower dielectric constant than that of the first dielectric body 51. The first dielectric body 51 has the cross-sectional shape in which the ratio between the major axis and the minor axis becomes constant in the longitudinal direction. The second dielectric body 52 is disposed in a region sandwiched by the first dielectric body 51 and the metal layer 53.SELECTED DRAWING: Figure 6COPYRIGHT: (C)2018,JPO&INPIT【課題】ミリ波以上の周波数の電波を伝送する導波管において適切な可撓性と優れた伝送特性とを両立する。【解決手段】長手方向に誘電率が均一、かつ、長手方向に断面が同一形状を呈する線状の誘電体と、誘電体の外周を覆う位置に配設され、可撓性を有する筒状により形成された金属層53とを有し、前記誘電体は、長手方向に垂直な断面において内側に位置する第1の誘電体51と、長手方向に垂直な断面において第1の誘電体51より外側に位置し第1の誘電体51よりも低い誘電率を備える第2の誘電体52と、を有し、第1の誘電体51は、長径と短径との比率が長手方向において一定となる断面形状を有し、第2の誘電体52は、第1の誘電体51と金属層53との間に挟まれる領域に配設される。【選択図】図6
