| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem that high-frequency signals can not be accurately propagated through a signal wiring conductor and a signal through conductor, and electronic parts mounted on a wiring board can not be normally operated. SOLUTION: Openings 8a and 9a whose areas are each equal to or larger than the sectional area of a signal through conductor 7 are formed in the regions of a first and a second grounding conductor layers, 8 and 9, confronted with the signal through conductor 7, and an opening 10a larger in area than the openings 8a and 9a is provided between a first and a second insulating layers, 1 and 2, and a third grounding conductor layer 10 surrounding the signal through conductor 7 through the intermediary of the opening 10a is provided. COPYRIGHT: (C)2004,JPO&NCIPI |
